Sweden-Number/dlls/mf/session.c

/*
 * Copyright 2017 Nikolay Sivov
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
 */

#include <stdarg.h>
#include <math.h>

#define COBJMACROS

#include "windef.h"
#include "winbase.h"
#include "mfidl.h"

#include "wine/debug.h"
#include "wine/heap.h"
#include "wine/list.h"

#include "mf_private.h"

WINE_DEFAULT_DEBUG_CHANNEL(mfplat);

enum session_command
{
    SESSION_CMD_CLEAR_TOPOLOGIES,
    SESSION_CMD_CLOSE,
    SESSION_CMD_SET_TOPOLOGY,
    SESSION_CMD_START,
    SESSION_CMD_PAUSE,
    SESSION_CMD_STOP,
    SESSION_CMD_END, /* Internal use only. */
};

struct session_op
{
    IUnknown IUnknown_iface;
    LONG refcount;
    enum session_command command;
    union
    {
        struct
        {
            DWORD flags;
            IMFTopology *topology;
        } set_topology;
        struct
        {
            GUID time_format;
            PROPVARIANT start_position;
        } start;
    } u;
    struct list entry;
};

struct queued_topology
{
    struct list entry;
    IMFTopology *topology;
    MF_TOPOSTATUS status;
};

enum session_state
{
    SESSION_STATE_STOPPED = 0,
    SESSION_STATE_STARTING_SOURCES,
    SESSION_STATE_PREROLLING_SINKS,
    SESSION_STATE_STARTING_SINKS,
    SESSION_STATE_STARTED,
    SESSION_STATE_PAUSING_SINKS,
    SESSION_STATE_PAUSING_SOURCES,
    SESSION_STATE_PAUSED,
    SESSION_STATE_STOPPING_SINKS,
    SESSION_STATE_STOPPING_SOURCES,
    SESSION_STATE_FINALIZING_SINKS,
    SESSION_STATE_CLOSED,
    SESSION_STATE_SHUT_DOWN,
};

enum object_state
{
    OBJ_STATE_STOPPED = 0,
    OBJ_STATE_STARTED,
    OBJ_STATE_PAUSED,
    OBJ_STATE_PREROLLED,
    OBJ_STATE_INVALID,
};

enum media_source_flags
{
    SOURCE_FLAG_END_OF_PRESENTATION = 0x1,
};

struct media_source
{
    struct list entry;
    IMFMediaSource *source;
    IMFPresentationDescriptor *pd;
    enum object_state state;
    unsigned int flags;
};

struct media_sink
{
    struct list entry;
    IMFMediaSink *sink;
    IMFMediaSinkPreroll *preroll;
    IMFMediaEventGenerator *event_generator;
    BOOL finalized;
};

struct sample
{
    struct list entry;
    IMFSample *sample;
};

struct transform_stream
{
    struct list samples;
    unsigned int requests;
};

enum topo_node_flags
{
    TOPO_NODE_END_OF_STREAM = 0x1,
};

struct topo_node
{
    struct list entry;
    MF_TOPOLOGY_TYPE type;
    TOPOID node_id;
    IMFTopologyNode *node;
    enum object_state state;
    unsigned int flags;
    union
    {
        IMFMediaStream *source_stream;
        IMFStreamSink *sink_stream;
        IMFTransform *transform;
        IUnknown *object;
    } object;

    union
    {
        struct
        {
            IMFMediaSource *source;
            unsigned int stream_id;
        } source;
        struct
        {
            unsigned int requests;
        } sink;
        struct
        {
            struct transform_stream *inputs;
            unsigned int *input_map;
            unsigned int input_count;

            struct transform_stream *outputs;
            unsigned int *output_map;
            unsigned int output_count;
        } transform;
    } u;
};

enum presentation_flags
{
    SESSION_FLAG_SOURCES_SUBSCRIBED = 0x1,
    SESSION_FLAG_PRESENTATION_CLOCK_SET = 0x2,
    SESSION_FLAG_FINALIZE_SINKS = 0x4,
    SESSION_FLAG_NEEDS_PREROLL = 0x8,
    SESSION_FLAG_END_OF_PRESENTATION = 0x10,
};

struct media_session
{
    IMFMediaSession IMFMediaSession_iface;
    IMFGetService IMFGetService_iface;
    IMFRateSupport IMFRateSupport_iface;
    IMFRateControl IMFRateControl_iface;
    IMFAsyncCallback commands_callback;
    IMFAsyncCallback events_callback;
    IMFAsyncCallback sink_finalizer_callback;
    LONG refcount;
    IMFMediaEventQueue *event_queue;
    IMFPresentationClock *clock;
    IMFPresentationTimeSource *system_time_source;
    IMFRateControl *clock_rate_control;
    IMFTopoLoader *topo_loader;
    IMFQualityManager *quality_manager;
    struct
    {
        IMFTopology *current_topology;
        MF_TOPOSTATUS topo_status;
        MFTIME clock_stop_time;
        unsigned int flags;
        struct list sources;
        struct list sinks;
        struct list nodes;

        /* Latest Start() arguments. */
        GUID time_format;
        PROPVARIANT start_position;
    } presentation;
    struct list topologies;
    struct list commands;
    enum session_state state;
    DWORD caps;
    CRITICAL_SECTION cs;
};

struct clock_sink
{
    struct list entry;
    IMFClockStateSink *state_sink;
};

enum clock_command
{
    CLOCK_CMD_START = 0,
    CLOCK_CMD_STOP,
    CLOCK_CMD_PAUSE,
    CLOCK_CMD_SET_RATE,
    CLOCK_CMD_MAX,
};

enum clock_notification
{
    CLOCK_NOTIFY_START,
    CLOCK_NOTIFY_STOP,
    CLOCK_NOTIFY_PAUSE,
    CLOCK_NOTIFY_RESTART,
    CLOCK_NOTIFY_SET_RATE,
};

struct clock_state_change_param
{
    union
    {
        LONGLONG offset;
        float rate;
    } u;
};

struct sink_notification
{
    IUnknown IUnknown_iface;
    LONG refcount;
    MFTIME system_time;
    struct clock_state_change_param param;
    enum clock_notification notification;
    IMFClockStateSink *sink;
};

struct clock_timer
{
    IUnknown IUnknown_iface;
    LONG refcount;
    IMFAsyncResult *result;
    IMFAsyncCallback *callback;
    MFWORKITEM_KEY key;
    struct list entry;
};

struct presentation_clock
{
    IMFPresentationClock IMFPresentationClock_iface;
    IMFRateControl IMFRateControl_iface;
    IMFTimer IMFTimer_iface;
    IMFShutdown IMFShutdown_iface;
    IMFAsyncCallback sink_callback;
    IMFAsyncCallback timer_callback;
    LONG refcount;
    IMFPresentationTimeSource *time_source;
    IMFClockStateSink *time_source_sink;
    MFCLOCK_STATE state;
    LONGLONG start_offset;
    struct list sinks;
    struct list timers;
    float rate;
    LONGLONG frequency;
    CRITICAL_SECTION cs;
    BOOL is_shut_down;
};

struct quality_manager
{
    IMFQualityManager IMFQualityManager_iface;
    LONG refcount;
};

static inline struct media_session *impl_from_IMFMediaSession(IMFMediaSession *iface)
{
    return CONTAINING_RECORD(iface, struct media_session, IMFMediaSession_iface);
}

static struct media_session *impl_from_commands_callback_IMFAsyncCallback(IMFAsyncCallback *iface)
{
    return CONTAINING_RECORD(iface, struct media_session, commands_callback);
}

static struct media_session *impl_from_events_callback_IMFAsyncCallback(IMFAsyncCallback *iface)
{
    return CONTAINING_RECORD(iface, struct media_session, events_callback);
}

static struct media_session *impl_from_sink_finalizer_callback_IMFAsyncCallback(IMFAsyncCallback *iface)
{
    return CONTAINING_RECORD(iface, struct media_session, sink_finalizer_callback);
}

static struct media_session *impl_from_IMFGetService(IMFGetService *iface)
{
    return CONTAINING_RECORD(iface, struct media_session, IMFGetService_iface);
}

static struct media_session *impl_session_from_IMFRateSupport(IMFRateSupport *iface)
{
    return CONTAINING_RECORD(iface, struct media_session, IMFRateSupport_iface);
}

static struct media_session *impl_session_from_IMFRateControl(IMFRateControl *iface)
{
    return CONTAINING_RECORD(iface, struct media_session, IMFRateControl_iface);
}

static struct session_op *impl_op_from_IUnknown(IUnknown *iface)
{
    return CONTAINING_RECORD(iface, struct session_op, IUnknown_iface);
}

static struct presentation_clock *impl_from_IMFPresentationClock(IMFPresentationClock *iface)
{
    return CONTAINING_RECORD(iface, struct presentation_clock, IMFPresentationClock_iface);
}

static struct presentation_clock *impl_from_IMFRateControl(IMFRateControl *iface)
{
    return CONTAINING_RECORD(iface, struct presentation_clock, IMFRateControl_iface);
}

static struct presentation_clock *impl_from_IMFTimer(IMFTimer *iface)
{
    return CONTAINING_RECORD(iface, struct presentation_clock, IMFTimer_iface);
}

static struct presentation_clock *impl_from_IMFShutdown(IMFShutdown *iface)
{
    return CONTAINING_RECORD(iface, struct presentation_clock, IMFShutdown_iface);
}

static struct presentation_clock *impl_from_sink_callback_IMFAsyncCallback(IMFAsyncCallback *iface)
{
    return CONTAINING_RECORD(iface, struct presentation_clock, sink_callback);
}

static struct presentation_clock *impl_from_timer_callback_IMFAsyncCallback(IMFAsyncCallback *iface)
{
    return CONTAINING_RECORD(iface, struct presentation_clock, timer_callback);
}

static struct clock_timer *impl_clock_timer_from_IUnknown(IUnknown *iface)
{
    return CONTAINING_RECORD(iface, struct clock_timer, IUnknown_iface);
}

static struct sink_notification *impl_sink_notification_from_IUnknown(IUnknown *iface)
{
    return CONTAINING_RECORD(iface, struct sink_notification, IUnknown_iface);
}

static struct quality_manager *impl_from_IMFQualityManager(IMFQualityManager *iface)
{
    return CONTAINING_RECORD(iface, struct quality_manager, IMFQualityManager_iface);
}

/* IMFLocalMFTRegistration */
static HRESULT WINAPI local_mft_registration_QueryInterface(IMFLocalMFTRegistration *iface, REFIID riid, void **obj)
{
    TRACE("%p, %s, %p.\n", iface, debugstr_guid(riid), obj);

    if (IsEqualIID(riid, &IID_IMFLocalMFTRegistration) ||
            IsEqualIID(riid, &IID_IUnknown))
    {
        *obj = iface;
        IMFLocalMFTRegistration_AddRef(iface);
        return S_OK;
    }

    WARN("Unexpected %s.\n", debugstr_guid(riid));
    *obj = NULL;
    return E_NOINTERFACE;
}

static ULONG WINAPI local_mft_registration_AddRef(IMFLocalMFTRegistration *iface)
{
    return 2;
}

static ULONG WINAPI local_mft_registration_Release(IMFLocalMFTRegistration *iface)
{
    return 1;
}

static HRESULT WINAPI local_mft_registration_RegisterMFTs(IMFLocalMFTRegistration *iface, MFT_REGISTRATION_INFO *info,
        DWORD count)
{
    HRESULT hr = S_OK;
    DWORD i;

    TRACE("%p, %p, %u.\n", iface, info, count);

    for (i = 0; i < count; ++i)
    {
        if (FAILED(hr = MFTRegisterLocalByCLSID(&info[i].clsid, &info[i].guidCategory, info[i].pszName,
                info[i].uiFlags, info[i].cInTypes, info[i].pInTypes, info[i].cOutTypes, info[i].pOutTypes)))
        {
            break;
        }
    }

    return hr;
}

static const IMFLocalMFTRegistrationVtbl local_mft_registration_vtbl =
{
    local_mft_registration_QueryInterface,
    local_mft_registration_AddRef,
    local_mft_registration_Release,
    local_mft_registration_RegisterMFTs,
};

static IMFLocalMFTRegistration local_mft_registration = { &local_mft_registration_vtbl };

static HRESULT WINAPI session_op_QueryInterface(IUnknown *iface, REFIID riid, void **obj)
{
    if (IsEqualIID(riid, &IID_IUnknown))
    {
        *obj = iface;
        IUnknown_AddRef(iface);
        return S_OK;
    }

    *obj = NULL;
    return E_NOINTERFACE;
}

static ULONG WINAPI session_op_AddRef(IUnknown *iface)
{
    struct session_op *op = impl_op_from_IUnknown(iface);
    ULONG refcount = InterlockedIncrement(&op->refcount);

    TRACE("%p, refcount %u.\n", iface, refcount);

    return refcount;
}

static ULONG WINAPI session_op_Release(IUnknown *iface)
{
    struct session_op *op = impl_op_from_IUnknown(iface);
    ULONG refcount = InterlockedDecrement(&op->refcount);

    TRACE("%p, refcount %u.\n", iface, refcount);

    if (!refcount)
    {
        switch (op->command)
        {
            case SESSION_CMD_SET_TOPOLOGY:
                if (op->u.set_topology.topology)
                    IMFTopology_Release(op->u.set_topology.topology);
                break;
            case SESSION_CMD_START:
                PropVariantClear(&op->u.start.start_position);
                break;
            default:
                ;
        }
        heap_free(op);
    }

    return refcount;
}

static IUnknownVtbl session_op_vtbl =
{
    session_op_QueryInterface,
    session_op_AddRef,
    session_op_Release,
};

static HRESULT create_session_op(enum session_command command, struct session_op **ret)
{
    struct session_op *op;

    if (!(op = heap_alloc_zero(sizeof(*op))))
        return E_OUTOFMEMORY;

    op->IUnknown_iface.lpVtbl = &session_op_vtbl;
    op->refcount = 1;
    op->command = command;

    *ret = op;

    return S_OK;
}

static HRESULT session_is_shut_down(struct media_session *session)
{
    return session->state == SESSION_STATE_SHUT_DOWN ? MF_E_SHUTDOWN : S_OK;
}

static void session_push_back_command(struct media_session *session, enum session_command command)
{
    struct session_op *op;

    if (SUCCEEDED(create_session_op(command, &op)))
        list_add_head(&session->commands, &op->entry);
}

static HRESULT session_submit_command(struct media_session *session, struct session_op *op)
{
    HRESULT hr;

    EnterCriticalSection(&session->cs);
    if (SUCCEEDED(hr = session_is_shut_down(session)))
    {
        if (list_empty(&session->commands))
            hr = MFPutWorkItem(MFASYNC_CALLBACK_QUEUE_STANDARD, &session->commands_callback, &op->IUnknown_iface);
        list_add_tail(&session->commands, &op->entry);
        IUnknown_AddRef(&op->IUnknown_iface);
    }
    LeaveCriticalSection(&session->cs);

    return hr;
}

static HRESULT session_submit_simple_command(struct media_session *session, enum session_command command)
{
    struct session_op *op;
    HRESULT hr;

    if (FAILED(hr = create_session_op(command, &op)))
        return hr;

    hr = session_submit_command(session, op);
    IUnknown_Release(&op->IUnknown_iface);
    return hr;
}

static void session_clear_topologies(struct media_session *session)
{
    struct queued_topology *ptr, *next;

    LIST_FOR_EACH_ENTRY_SAFE(ptr, next, &session->topologies, struct queued_topology, entry)
    {
        list_remove(&ptr->entry);
        IMFTopology_Release(ptr->topology);
        heap_free(ptr);
    }
}

static void session_set_topo_status(struct media_session *session, HRESULT status,
        MF_TOPOSTATUS topo_status)
{
    IMFMediaEvent *event;
    PROPVARIANT param;

    if (topo_status == MF_TOPOSTATUS_INVALID)
        return;

    if (list_empty(&session->topologies))
    {
        FIXME("Unexpectedly empty topology queue.\n");
        return;
    }

    if (topo_status > session->presentation.topo_status)
    {
        struct queued_topology *topology = LIST_ENTRY(list_head(&session->topologies), struct queued_topology, entry);

        param.vt = VT_UNKNOWN;
        param.punkVal = (IUnknown *)topology->topology;

        if (FAILED(MFCreateMediaEvent(MESessionTopologyStatus, &GUID_NULL, status, &param, &event)))
            return;

        session->presentation.topo_status = topo_status;

        IMFMediaEvent_SetUINT32(event, &MF_EVENT_TOPOLOGY_STATUS, topo_status);
        IMFMediaEventQueue_QueueEvent(session->event_queue, event);
        IMFMediaEvent_Release(event);
    }
}

static HRESULT session_bind_output_nodes(IMFTopology *topology)
{
    MF_TOPOLOGY_TYPE node_type;
    IMFStreamSink *stream_sink;
    IMFMediaSink *media_sink;
    WORD node_count = 0, i;
    IMFTopologyNode *node;
    IMFActivate *activate;
    UINT32 stream_id;
    IUnknown *object;
    HRESULT hr;

    hr = IMFTopology_GetNodeCount(topology, &node_count);

    for (i = 0; i < node_count; ++i)
    {
        if (FAILED(hr = IMFTopology_GetNode(topology, i, &node)))
            break;

        if (FAILED(hr = IMFTopologyNode_GetNodeType(node, &node_type)) || node_type != MF_TOPOLOGY_OUTPUT_NODE)
        {
            IMFTopologyNode_Release(node);
            continue;
        }

        if (SUCCEEDED(hr = IMFTopologyNode_GetObject(node, &object)))
        {
            stream_sink = NULL;
            if (FAILED(IUnknown_QueryInterface(object, &IID_IMFStreamSink, (void **)&stream_sink)))
            {
                if (SUCCEEDED(hr = IUnknown_QueryInterface(object, &IID_IMFActivate, (void **)&activate)))
                {
                    if (SUCCEEDED(hr = IMFActivate_ActivateObject(activate, &IID_IMFMediaSink, (void **)&media_sink)))
                    {
                        if (FAILED(IMFTopologyNode_GetUINT32(node, &MF_TOPONODE_STREAMID, &stream_id)))
                            stream_id = 0;

                        stream_sink = NULL;
                        if (FAILED(IMFMediaSink_GetStreamSinkById(media_sink, stream_id, &stream_sink)))
                            hr = IMFMediaSink_AddStreamSink(media_sink, stream_id, NULL, &stream_sink);

                        if (stream_sink)
                            hr = IMFTopologyNode_SetObject(node, (IUnknown *)stream_sink);

                        IMFMediaSink_Release(media_sink);
                    }

                    IMFActivate_Release(activate);
                }
            }

            if (stream_sink)
                IMFStreamSink_Release(stream_sink);
            IUnknown_Release(object);
        }

        IMFTopologyNode_Release(node);
    }

    return hr;
}

static void session_set_caps(struct media_session *session, DWORD caps)
{
    DWORD delta = session->caps ^ caps;
    IMFMediaEvent *event;

    /* Delta is documented to reflect rate value changes as well, but it's not clear what to compare
       them to, since session always queries for current object rates. */
    if (!delta)
        return;

    session->caps = caps;

    if (FAILED(MFCreateMediaEvent(MESessionCapabilitiesChanged, &GUID_NULL, S_OK, NULL, &event)))
        return;

    IMFMediaEvent_SetUINT32(event, &MF_EVENT_SESSIONCAPS, caps);
    IMFMediaEvent_SetUINT32(event, &MF_EVENT_SESSIONCAPS_DELTA, delta);

    IMFMediaEventQueue_QueueEvent(session->event_queue, event);
    IMFMediaEvent_Release(event);
}

static void transform_release_sample(struct sample *sample)
{
    list_remove(&sample->entry);
    if (sample->sample)
        IMFSample_Release(sample->sample);
    heap_free(sample);
}

static void transform_stream_drop_samples(struct transform_stream *stream)
{
    struct sample *sample, *sample2;

    LIST_FOR_EACH_ENTRY_SAFE(sample, sample2, &stream->samples, struct sample, entry)
        transform_release_sample(sample);
}

static void release_topo_node(struct topo_node *node)
{
    unsigned int i;

    switch (node->type)
    {
        case MF_TOPOLOGY_SOURCESTREAM_NODE:
            if (node->u.source.source)
                IMFMediaSource_Release(node->u.source.source);
            break;
        case MF_TOPOLOGY_TRANSFORM_NODE:
            for (i = 0; i < node->u.transform.input_count; ++i)
                transform_stream_drop_samples(&node->u.transform.inputs[i]);
            for (i = 0; i < node->u.transform.output_count; ++i)
                transform_stream_drop_samples(&node->u.transform.outputs[i]);
            heap_free(node->u.transform.inputs);
            heap_free(node->u.transform.outputs);
            heap_free(node->u.transform.input_map);
            heap_free(node->u.transform.output_map);
            break;
        default:
            ;
    }

    if (node->object.object)
        IUnknown_Release(node->object.object);
    if (node->node)
        IMFTopologyNode_Release(node->node);
    heap_free(node);
}

static void session_clear_presentation(struct media_session *session)
{
    struct media_source *source, *source2;
    struct media_sink *sink, *sink2;
    struct topo_node *node, *node2;
    struct session_op *op, *op2;

    IMFTopology_Clear(session->presentation.current_topology);
    session->presentation.topo_status = MF_TOPOSTATUS_INVALID;

    LIST_FOR_EACH_ENTRY_SAFE(source, source2, &session->presentation.sources, struct media_source, entry)
    {
        list_remove(&source->entry);
        if (source->source)
            IMFMediaSource_Release(source->source);
        if (source->pd)
            IMFPresentationDescriptor_Release(source->pd);
        heap_free(source);
    }

    LIST_FOR_EACH_ENTRY_SAFE(node, node2, &session->presentation.nodes, struct topo_node, entry)
    {
        list_remove(&node->entry);
        release_topo_node(node);
    }

    LIST_FOR_EACH_ENTRY_SAFE(sink, sink2, &session->presentation.sinks, struct media_sink, entry)
    {
        list_remove(&sink->entry);

        if (sink->sink)
            IMFMediaSink_Release(sink->sink);
        if (sink->preroll)
            IMFMediaSinkPreroll_Release(sink->preroll);
        if (sink->event_generator)
            IMFMediaEventGenerator_Release(sink->event_generator);
        heap_free(sink);
    }

    LIST_FOR_EACH_ENTRY_SAFE(op, op2, &session->commands, struct session_op, entry)
    {
        list_remove(&op->entry);
        IUnknown_Release(&op->IUnknown_iface);
    }
}

static void session_start(struct media_session *session, const GUID *time_format, const PROPVARIANT *start_position)
{
    struct media_source *source;
    HRESULT hr;

    switch (session->state)
    {
        case SESSION_STATE_STOPPED:
        case SESSION_STATE_PAUSED:

            session->presentation.time_format = *time_format;
            session->presentation.start_position.vt = VT_EMPTY;
            PropVariantCopy(&session->presentation.start_position, start_position);

            LIST_FOR_EACH_ENTRY(source, &session->presentation.sources, struct media_source, entry)
            {
                if (!(session->presentation.flags & SESSION_FLAG_SOURCES_SUBSCRIBED))
                {
                    if (FAILED(hr = IMFMediaSource_BeginGetEvent(source->source, &session->events_callback,
                            (IUnknown *)source->source)))
                    {
                        WARN("Failed to subscribe to source events, hr %#x.\n", hr);
                    }
                }

                if (FAILED(hr = IMFMediaSource_Start(source->source, source->pd, &GUID_NULL, start_position)))
                    WARN("Failed to start media source %p, hr %#x.\n", source->source, hr);
            }

            session->presentation.flags |= SESSION_FLAG_SOURCES_SUBSCRIBED;
            session->state = SESSION_STATE_STARTING_SOURCES;
            break;
        case SESSION_STATE_STARTED:
            FIXME("Seeking is not implemented.\n");
            break;
        case SESSION_STATE_CLOSED:
            IMFMediaEventQueue_QueueEventParamVar(session->event_queue, MESessionStarted, &GUID_NULL,
                    MF_E_INVALIDREQUEST, NULL);
            break;
        default:
            ;
    }
}

static void session_command_complete(struct media_session *session)
{
    struct session_op *op;
    struct list *e;

    /* Pop current command, submit next. */
    if ((e = list_head(&session->commands)))
    {
        op = LIST_ENTRY(e, struct session_op, entry);
        list_remove(&op->entry);
        IUnknown_Release(&op->IUnknown_iface);
    }

    if ((e = list_head(&session->commands)))
    {
        op = LIST_ENTRY(e, struct session_op, entry);
        MFPutWorkItem(MFASYNC_CALLBACK_QUEUE_STANDARD, &session->commands_callback, &op->IUnknown_iface);
    }
}

static void session_set_started(struct media_session *session)
{
    struct media_source *source;
    unsigned int caps, flags;
    IMFMediaEvent *event;

    session->state = SESSION_STATE_STARTED;

    caps = session->caps | MFSESSIONCAP_PAUSE;

    LIST_FOR_EACH_ENTRY(source, &session->presentation.sources, struct media_source, entry)
    {
        if (SUCCEEDED(IMFMediaSource_GetCharacteristics(source->source, &flags)))
        {
            if (!(flags & MFMEDIASOURCE_CAN_PAUSE))
            {
                caps &= ~MFSESSIONCAP_PAUSE;
                break;
            }
        }
    }

    session_set_caps(session, caps);

    if (SUCCEEDED(MFCreateMediaEvent(MESessionStarted, &GUID_NULL, S_OK, NULL, &event)))
    {
        IMFMediaEvent_SetUINT64(event, &MF_EVENT_PRESENTATION_TIME_OFFSET, 0);
        IMFMediaEventQueue_QueueEvent(session->event_queue, event);
        IMFMediaEvent_Release(event);
    }
    session_command_complete(session);
}

static void session_set_paused(struct media_session *session, HRESULT status)
{
    session->state = SESSION_STATE_PAUSED;
    if (SUCCEEDED(status))
        session_set_caps(session, session->caps & ~MFSESSIONCAP_PAUSE);
    IMFMediaEventQueue_QueueEventParamVar(session->event_queue, MESessionPaused, &GUID_NULL, status, NULL);
    session_command_complete(session);
}

static void session_set_closed(struct media_session *session, HRESULT status)
{
    session->state = SESSION_STATE_CLOSED;
    if (SUCCEEDED(status))
        session_set_caps(session, session->caps & ~(MFSESSIONCAP_START | MFSESSIONCAP_SEEK));
    IMFMediaEventQueue_QueueEventParamVar(session->event_queue, MESessionClosed, &GUID_NULL, status, NULL);
    session_command_complete(session);
}

static void session_pause(struct media_session *session)
{
    HRESULT hr;

    switch (session->state)
    {
        case SESSION_STATE_STARTED:

            /* Transition in two steps - pause clock, wait for sinks and pause sources. */
            if (SUCCEEDED(hr = IMFPresentationClock_Pause(session->clock)))
                session->state = SESSION_STATE_PAUSING_SINKS;

            break;
        default:
            hr = MF_E_INVALIDREQUEST;
    }

    if (FAILED(hr))
        session_set_paused(session, hr);
}

static void session_set_stopped(struct media_session *session, HRESULT status)
{
    MediaEventType event_type;
    IMFMediaEvent *event;

    session->state = SESSION_STATE_STOPPED;
    event_type = session->presentation.flags & SESSION_FLAG_END_OF_PRESENTATION ? MESessionEnded : MESessionStopped;

    if (SUCCEEDED(MFCreateMediaEvent(event_type, &GUID_NULL, status, NULL, &event)))
    {
        IMFMediaEvent_SetUINT64(event, &MF_SESSION_APPROX_EVENT_OCCURRENCE_TIME, session->presentation.clock_stop_time);
        IMFMediaEventQueue_QueueEvent(session->event_queue, event);
        IMFMediaEvent_Release(event);
    }
    session_command_complete(session);
}

static void session_stop(struct media_session *session)
{
    HRESULT hr = MF_E_INVALIDREQUEST;

    switch (session->state)
    {
        case SESSION_STATE_STARTED:
        case SESSION_STATE_PAUSED:

            /* Transition in two steps - pause clock, wait for sinks and pause sources. */
            IMFPresentationClock_GetTime(session->clock, &session->presentation.clock_stop_time);
            if (SUCCEEDED(hr = IMFPresentationClock_Stop(session->clock)))
                session->state = SESSION_STATE_STOPPING_SINKS;
            else
                session_set_stopped(session, hr);

            break;
        case SESSION_STATE_STOPPED:
            hr = S_OK;
            /* fallthrough */
        default:
            IMFMediaEventQueue_QueueEventParamVar(session->event_queue, MESessionStopped, &GUID_NULL, hr, NULL);
            session_command_complete(session);
            break;
    }
}

static HRESULT session_finalize_sinks(struct media_session *session)
{
    IMFFinalizableMediaSink *fin_sink;
    BOOL sinks_finalized = TRUE;
    struct media_sink *sink;
    HRESULT hr = S_OK;

    session->presentation.flags &= ~SESSION_FLAG_FINALIZE_SINKS;
    session->state = SESSION_STATE_FINALIZING_SINKS;

    LIST_FOR_EACH_ENTRY(sink, &session->presentation.sinks, struct media_sink, entry)
    {
        if (SUCCEEDED(IMFMediaSink_QueryInterface(sink->sink, &IID_IMFFinalizableMediaSink, (void **)&fin_sink)))
        {
            hr = IMFFinalizableMediaSink_BeginFinalize(fin_sink, &session->sink_finalizer_callback,
                    (IUnknown *)fin_sink);
            IMFFinalizableMediaSink_Release(fin_sink);
            if (FAILED(hr))
                break;
            sinks_finalized = FALSE;
        }
        else
            sink->finalized = TRUE;
    }

    if (sinks_finalized)
        session_set_closed(session, hr);

    return hr;
}

static void session_close(struct media_session *session)
{
    HRESULT hr = S_OK;

    switch (session->state)
    {
        case SESSION_STATE_STOPPED:
            hr = session_finalize_sinks(session);
            break;
        case SESSION_STATE_STARTED:
        case SESSION_STATE_PAUSED:
            session->presentation.flags |= SESSION_FLAG_FINALIZE_SINKS;
            if (SUCCEEDED(hr = IMFPresentationClock_Stop(session->clock)))
                session->state = SESSION_STATE_STOPPING_SINKS;
            break;
        default:
            hr = MF_E_INVALIDREQUEST;
            break;
    }

    if (FAILED(hr))
        session_set_closed(session, hr);
}

static struct media_source *session_get_media_source(struct media_session *session, IMFMediaSource *source)
{
    struct media_source *cur;

    LIST_FOR_EACH_ENTRY(cur, &session->presentation.sources, struct media_source, entry)
    {
        if (source == cur->source)
            return cur;
    }

    return NULL;
}

static void session_release_media_source(struct media_source *source)
{
    IMFMediaSource_Release(source->source);
    if (source->pd)
        IMFPresentationDescriptor_Release(source->pd);
    heap_free(source);
}

static HRESULT session_add_media_source(struct media_session *session, IMFTopologyNode *node, IMFMediaSource *source)
{
    struct media_source *media_source;
    HRESULT hr;

    if (session_get_media_source(session, source))
        return S_FALSE;

    if (!(media_source = heap_alloc_zero(sizeof(*media_source))))
        return E_OUTOFMEMORY;

    media_source->source = source;
    IMFMediaSource_AddRef(media_source->source);

    hr = IMFTopologyNode_GetUnknown(node, &MF_TOPONODE_PRESENTATION_DESCRIPTOR, &IID_IMFPresentationDescriptor,
            (void **)&media_source->pd);

    if (SUCCEEDED(hr))
        list_add_tail(&session->presentation.sources, &media_source->entry);
    else
        session_release_media_source(media_source);

    return hr;
}

static void session_raise_topology_set(struct media_session *session, IMFTopology *topology, HRESULT status)
{
    PROPVARIANT param;

    param.vt = topology ? VT_UNKNOWN : VT_EMPTY;
    param.punkVal = (IUnknown *)topology;

    IMFMediaEventQueue_QueueEventParamVar(session->event_queue, MESessionTopologySet, &GUID_NULL, status, &param);
}

static DWORD session_get_object_rate_caps(IUnknown *object)
{
    IMFRateSupport *rate_support;
    DWORD caps = 0;
    float rate;

    if (SUCCEEDED(MFGetService(object, &MF_RATE_CONTROL_SERVICE, &IID_IMFRateSupport, (void **)&rate_support)))
    {
        rate = 0.0f;
        if (SUCCEEDED(IMFRateSupport_GetFastestRate(rate_support, MFRATE_FORWARD, TRUE, &rate)) && rate != 0.0f)
            caps |= MFSESSIONCAP_RATE_FORWARD;

        rate = 0.0f;
        if (SUCCEEDED(IMFRateSupport_GetFastestRate(rate_support, MFRATE_REVERSE, TRUE, &rate)) && rate != 0.0f)
            caps |= MFSESSIONCAP_RATE_REVERSE;

        IMFRateSupport_Release(rate_support);
    }

    return caps;
}

static HRESULT session_add_media_sink(struct media_session *session, IMFTopologyNode *node, IMFMediaSink *sink)
{
    struct media_sink *media_sink;
    DWORD flags;

    LIST_FOR_EACH_ENTRY(media_sink, &session->presentation.sinks, struct media_sink, entry)
    {
        if (sink == media_sink->sink)
            return S_FALSE;
    }

    if (!(media_sink = heap_alloc_zero(sizeof(*media_sink))))
        return E_OUTOFMEMORY;

    media_sink->sink = sink;
    IMFMediaSink_AddRef(media_sink->sink);

    IMFMediaSink_QueryInterface(media_sink->sink, &IID_IMFMediaEventGenerator, (void **)&media_sink->event_generator);

    if (SUCCEEDED(IMFMediaSink_GetCharacteristics(sink, &flags)) && flags & MEDIASINK_CAN_PREROLL)
    {
        if (SUCCEEDED(IMFMediaSink_QueryInterface(media_sink->sink, &IID_IMFMediaSinkPreroll, (void **)&media_sink->preroll)))
            session->presentation.flags |= SESSION_FLAG_NEEDS_PREROLL;
    }

    list_add_tail(&session->presentation.sinks, &media_sink->entry);

    return S_OK;
}

static HRESULT session_set_transform_stream_info(struct topo_node *node)
{
    unsigned int *input_map = NULL, *output_map = NULL;
    unsigned int i, input_count, output_count;
    struct transform_stream *streams;
    HRESULT hr;

    hr = IMFTransform_GetStreamCount(node->object.transform, &input_count, &output_count);
    if (SUCCEEDED(hr) && (input_count > 1 || output_count > 1))
    {
        input_map = heap_calloc(input_count, sizeof(*input_map));
        output_map = heap_calloc(output_count, sizeof(*output_map));
        if (FAILED(IMFTransform_GetStreamIDs(node->object.transform, input_count, input_map,
                output_count, output_map)))
        {
            /* Assume sequential identifiers. */
            heap_free(input_map);
            heap_free(output_map);
            input_map = output_map = NULL;
        }
    }

    if (SUCCEEDED(hr))
    {
        streams = heap_calloc(input_count, sizeof(*streams));
        for (i = 0; i < input_count; ++i)
            list_init(&streams[i].samples);
        node->u.transform.inputs = streams;

        streams = heap_calloc(output_count, sizeof(*streams));
        for (i = 0; i < output_count; ++i)
            list_init(&streams[i].samples);
        node->u.transform.outputs = streams;

        node->u.transform.input_count = input_count;
        node->u.transform.output_count = output_count;
        node->u.transform.input_map = input_map;
        node->u.transform.output_map = output_map;
    }

    return hr;
}

static HRESULT session_append_node(struct media_session *session, IMFTopologyNode *node)
{
    struct topo_node *topo_node;
    IMFMediaSink *media_sink;
    IMFStreamDescriptor *sd;
    HRESULT hr = S_OK;
    IUnknown *object;

    if (!(topo_node = heap_alloc_zero(sizeof(*topo_node))))
        return E_OUTOFMEMORY;

    IMFTopologyNode_GetNodeType(node, &topo_node->type);
    IMFTopologyNode_GetTopoNodeID(node, &topo_node->node_id);
    topo_node->node = node;
    IMFTopologyNode_AddRef(topo_node->node);

    switch (topo_node->type)
    {
        case MF_TOPOLOGY_OUTPUT_NODE:
            if (FAILED(hr = IMFTopologyNode_GetObject(node, &object)))
            {
                WARN("Node %s does not have associated object.\n", wine_dbgstr_longlong(topo_node->node_id));
                break;
            }
            hr = IUnknown_QueryInterface(object, &IID_IMFStreamSink, (void **)&topo_node->object.object);
            IUnknown_Release(object);
            if (FAILED(hr))
                break;

            if (FAILED(hr = IMFStreamSink_GetMediaSink(topo_node->object.sink_stream, &media_sink)))
                break;

            hr = session_add_media_sink(session, node, media_sink);
            IMFMediaSink_Release(media_sink);

            break;
        case MF_TOPOLOGY_SOURCESTREAM_NODE:
            if (FAILED(IMFTopologyNode_GetUnknown(node, &MF_TOPONODE_SOURCE, &IID_IMFMediaSource,
                    (void **)&topo_node->u.source.source)))
            {
                WARN("Missing MF_TOPONODE_SOURCE, hr %#x.\n", hr);
                break;
            }

            if (FAILED(hr = session_add_media_source(session, node, topo_node->u.source.source)))
                break;

            if (FAILED(hr = IMFTopologyNode_GetUnknown(node, &MF_TOPONODE_STREAM_DESCRIPTOR,
                    &IID_IMFStreamDescriptor, (void **)&sd)))
            {
                WARN("Missing MF_TOPONODE_STREAM_DESCRIPTOR, hr %#x.\n", hr);
                break;
            }

            hr = IMFStreamDescriptor_GetStreamIdentifier(sd, &topo_node->u.source.stream_id);
            IMFStreamDescriptor_Release(sd);

            break;
        case MF_TOPOLOGY_TRANSFORM_NODE:
            if (SUCCEEDED(hr = IMFTopologyNode_GetObject(node, &object)))
            {
                hr = IUnknown_QueryInterface(object, &IID_IMFTransform, (void **)&topo_node->object.transform);
                IUnknown_Release(object);
            }

            if (SUCCEEDED(hr))
                hr = session_set_transform_stream_info(topo_node);
            else
                WARN("Failed to get IMFTransform for MFT node, hr %#x.\n", hr);

            break;
        case MF_TOPOLOGY_TEE_NODE:
            FIXME("Unsupported node type %d.\n", topo_node->type);

            break;
        default:
            ;
    }

    if (SUCCEEDED(hr))
        list_add_tail(&session->presentation.nodes, &topo_node->entry);
    else
        release_topo_node(topo_node);

    return hr;
}

static HRESULT session_collect_nodes(struct media_session *session)
{
    IMFTopology *topology = session->presentation.current_topology;
    IMFTopologyNode *node;
    WORD i, count = 0;
    HRESULT hr;

    if (!list_empty(&session->presentation.nodes))
        return S_OK;

    if (FAILED(hr = IMFTopology_GetNodeCount(topology, &count)))
        return hr;

    for (i = 0; i < count; ++i)
    {
        if (FAILED(hr = IMFTopology_GetNode(topology, i, &node)))
        {
            WARN("Failed to get node %u.\n", i);
            break;
        }

        hr = session_append_node(session, node);
        IMFTopologyNode_Release(node);
        if (FAILED(hr))
        {
            WARN("Failed to add node %u.\n", i);
            break;
        }
    }

    return hr;
}

static HRESULT session_set_current_topology(struct media_session *session, IMFTopology *topology)
{
    struct media_source *source;
    DWORD caps, object_flags;
    struct media_sink *sink;
    struct topo_node *node;
    IMFMediaEvent *event;
    HRESULT hr;

    if (FAILED(hr = IMFTopology_CloneFrom(session->presentation.current_topology, topology)))
    {
        WARN("Failed to clone topology, hr %#x.\n", hr);
        return hr;
    }

    session_collect_nodes(session);

    LIST_FOR_EACH_ENTRY(node, &session->presentation.nodes, struct topo_node, entry)
    {
        if (node->type == MF_TOPOLOGY_TRANSFORM_NODE)
        {
            if (FAILED(hr = IMFTransform_ProcessMessage(node->object.transform,
                    MFT_MESSAGE_NOTIFY_BEGIN_STREAMING, 0)))
                return hr;
        }
    }

    /* FIXME: attributes are all zero for now */
    if (SUCCEEDED(MFCreateMediaEvent(MESessionNotifyPresentationTime, &GUID_NULL, S_OK, NULL, &event)))
    {
        IMFMediaEvent_SetUINT64(event, &MF_EVENT_START_PRESENTATION_TIME, 0);
        IMFMediaEvent_SetUINT64(event, &MF_EVENT_PRESENTATION_TIME_OFFSET, 0);
        IMFMediaEvent_SetUINT64(event, &MF_EVENT_START_PRESENTATION_TIME_AT_OUTPUT, 0);

        IMFMediaEventQueue_QueueEvent(session->event_queue, event);
        IMFMediaEvent_Release(event);
    }

    /* Update session caps. */
    caps = MFSESSIONCAP_START | MFSESSIONCAP_SEEK | MFSESSIONCAP_RATE_FORWARD | MFSESSIONCAP_RATE_REVERSE |
            MFSESSIONCAP_DOES_NOT_USE_NETWORK;

    LIST_FOR_EACH_ENTRY(source, &session->presentation.sources, struct media_source, entry)
    {
        if (!caps)
            break;

        object_flags = 0;
        if (SUCCEEDED(IMFMediaSource_GetCharacteristics(source->source, &object_flags)))
        {
            if (!(object_flags & MFMEDIASOURCE_DOES_NOT_USE_NETWORK))
                caps &= ~MFSESSIONCAP_DOES_NOT_USE_NETWORK;
            if (!(object_flags & MFMEDIASOURCE_CAN_SEEK))
                caps &= ~MFSESSIONCAP_SEEK;
        }

        /* Mask unsupported rate caps. */

        caps &= session_get_object_rate_caps((IUnknown *)source->source)
                | ~(MFSESSIONCAP_RATE_FORWARD | MFSESSIONCAP_RATE_REVERSE);
    }

    LIST_FOR_EACH_ENTRY(sink, &session->presentation.sinks, struct media_sink, entry)
    {
        if (!caps)
            break;

        object_flags = 0;
        if (SUCCEEDED(IMFMediaSink_GetCharacteristics(sink->sink, &object_flags)))
        {
            if (!(object_flags & MEDIASINK_RATELESS))
                caps &= session_get_object_rate_caps((IUnknown *)sink->sink)
                        | ~(MFSESSIONCAP_RATE_FORWARD | MFSESSIONCAP_RATE_REVERSE);
        }
    }

    session_set_caps(session, caps);

    return S_OK;
}

static void session_set_topology(struct media_session *session, DWORD flags, IMFTopology *topology)
{
    IMFTopology *resolved_topology = NULL;
    HRESULT hr = S_OK;

    /* Resolve unless claimed to be full. */
    if (!(flags & MFSESSION_SETTOPOLOGY_CLEAR_CURRENT) && topology)
    {
        if (!(flags & MFSESSION_SETTOPOLOGY_NORESOLUTION))
        {
            hr = session_bind_output_nodes(topology);

            if (SUCCEEDED(hr))
                hr = IMFTopoLoader_Load(session->topo_loader, topology, &resolved_topology, NULL /* FIXME? */);

            if (SUCCEEDED(hr))
            {
                topology = resolved_topology;
            }
        }
    }

    if (flags & MFSESSION_SETTOPOLOGY_CLEAR_CURRENT)
    {
        if ((topology && topology == session->presentation.current_topology) || !topology)
        {
            /* FIXME: stop current topology, queue next one. */
            session_clear_presentation(session);
        }
        else
            hr = S_FALSE;

        topology = NULL;
    }
    else if (topology && flags & MFSESSION_SETTOPOLOGY_IMMEDIATE)
    {
        session_clear_topologies(session);
        session_clear_presentation(session);
    }

    session_raise_topology_set(session, topology, hr);

    /* With no current topology set it right away, otherwise queue. */
    if (topology)
    {
        struct queued_topology *queued_topology;

        if ((queued_topology = heap_alloc_zero(sizeof(*queued_topology))))
        {
            queued_topology->topology = topology;
            IMFTopology_AddRef(queued_topology->topology);

            list_add_tail(&session->topologies, &queued_topology->entry);
        }

        if (session->presentation.topo_status == MF_TOPOSTATUS_INVALID)
        {
            hr = session_set_current_topology(session, topology);
            session_set_topo_status(session, hr, MF_TOPOSTATUS_READY);
        }
    }

    if (resolved_topology)
        IMFTopology_Release(resolved_topology);
}

static HRESULT WINAPI mfsession_QueryInterface(IMFMediaSession *iface, REFIID riid, void **out)
{
    struct media_session *session = impl_from_IMFMediaSession(iface);

    TRACE("%p, %s, %p.\n", iface, debugstr_guid(riid), out);

    if (IsEqualIID(riid, &IID_IMFMediaSession) ||
            IsEqualIID(riid, &IID_IMFMediaEventGenerator) ||
            IsEqualIID(riid, &IID_IUnknown))
    {
        *out = &session->IMFMediaSession_iface;
        IMFMediaSession_AddRef(iface);
        return S_OK;
    }
    else if (IsEqualIID(riid, &IID_IMFGetService))
    {
        *out = &session->IMFGetService_iface;
        IMFMediaSession_AddRef(iface);
        return S_OK;
    }

    WARN("Unsupported %s.\n", debugstr_guid(riid));
    *out = NULL;
    return E_NOINTERFACE;
}

static ULONG WINAPI mfsession_AddRef(IMFMediaSession *iface)
{
    struct media_session *session = impl_from_IMFMediaSession(iface);
    ULONG refcount = InterlockedIncrement(&session->refcount);

    TRACE("%p, refcount %u.\n", iface, refcount);

    return refcount;
}

static ULONG WINAPI mfsession_Release(IMFMediaSession *iface)
{
    struct media_session *session = impl_from_IMFMediaSession(iface);
    ULONG refcount = InterlockedDecrement(&session->refcount);

    TRACE("%p, refcount %u.\n", iface, refcount);

    if (!refcount)
    {
        session_clear_topologies(session);
        session_clear_presentation(session);
        if (session->presentation.current_topology)
            IMFTopology_Release(session->presentation.current_topology);
        if (session->event_queue)
            IMFMediaEventQueue_Release(session->event_queue);
        if (session->clock)
            IMFPresentationClock_Release(session->clock);
        if (session->system_time_source)
            IMFPresentationTimeSource_Release(session->system_time_source);
        if (session->clock_rate_control)
            IMFRateControl_Release(session->clock_rate_control);
        if (session->topo_loader)
            IMFTopoLoader_Release(session->topo_loader);
        if (session->quality_manager)
            IMFQualityManager_Release(session->quality_manager);
        DeleteCriticalSection(&session->cs);
        heap_free(session);
    }

    return refcount;
}

static HRESULT WINAPI mfsession_GetEvent(IMFMediaSession *iface, DWORD flags, IMFMediaEvent **event)
{
    struct media_session *session = impl_from_IMFMediaSession(iface);

    TRACE("%p, %#x, %p.\n", iface, flags, event);

    return IMFMediaEventQueue_GetEvent(session->event_queue, flags, event);
}

static HRESULT WINAPI mfsession_BeginGetEvent(IMFMediaSession *iface, IMFAsyncCallback *callback, IUnknown *state)
{
    struct media_session *session = impl_from_IMFMediaSession(iface);

    TRACE("%p, %p, %p.\n", iface, callback, state);

    return IMFMediaEventQueue_BeginGetEvent(session->event_queue, callback, state);
}

static HRESULT WINAPI mfsession_EndGetEvent(IMFMediaSession *iface, IMFAsyncResult *result, IMFMediaEvent **event)
{
    struct media_session *session = impl_from_IMFMediaSession(iface);

    TRACE("%p, %p, %p.\n", iface, result, event);

    return IMFMediaEventQueue_EndGetEvent(session->event_queue, result, event);
}

static HRESULT WINAPI mfsession_QueueEvent(IMFMediaSession *iface, MediaEventType event_type, REFGUID ext_type,
        HRESULT hr, const PROPVARIANT *value)
{
    struct media_session *session = impl_from_IMFMediaSession(iface);

    TRACE("%p, %d, %s, %#x, %p.\n", iface, event_type, debugstr_guid(ext_type), hr, value);

    return IMFMediaEventQueue_QueueEventParamVar(session->event_queue, event_type, ext_type, hr, value);
}

static HRESULT WINAPI mfsession_SetTopology(IMFMediaSession *iface, DWORD flags, IMFTopology *topology)
{
    struct media_session *session = impl_from_IMFMediaSession(iface);
    struct session_op *op;
    WORD node_count = 0;
    HRESULT hr;

    TRACE("%p, %#x, %p.\n", iface, flags, topology);

    if (topology)
    {
        if (FAILED(IMFTopology_GetNodeCount(topology, &node_count)) || node_count == 0)
            return E_INVALIDARG;
    }

    if (FAILED(hr = create_session_op(SESSION_CMD_SET_TOPOLOGY, &op)))
        return hr;

    op->u.set_topology.flags = flags;
    op->u.set_topology.topology = topology;
    if (op->u.set_topology.topology)
        IMFTopology_AddRef(op->u.set_topology.topology);

    hr = session_submit_command(session, op);
    IUnknown_Release(&op->IUnknown_iface);

    return hr;
}

static HRESULT WINAPI mfsession_ClearTopologies(IMFMediaSession *iface)
{
    struct media_session *session = impl_from_IMFMediaSession(iface);

    TRACE("%p.\n", iface);

    return session_submit_simple_command(session, SESSION_CMD_CLEAR_TOPOLOGIES);
}

static HRESULT WINAPI mfsession_Start(IMFMediaSession *iface, const GUID *format, const PROPVARIANT *start_position)
{
    struct media_session *session = impl_from_IMFMediaSession(iface);
    struct session_op *op;
    HRESULT hr;

    TRACE("%p, %s, %p.\n", iface, debugstr_guid(format), start_position);

    if (!start_position)
        return E_POINTER;

    if (FAILED(hr = create_session_op(SESSION_CMD_START, &op)))
        return hr;

    op->u.start.time_format = format ? *format : GUID_NULL;
    hr = PropVariantCopy(&op->u.start.start_position, start_position);

    if (SUCCEEDED(hr))
        hr = session_submit_command(session, op);

    IUnknown_Release(&op->IUnknown_iface);

    return hr;
}

static HRESULT WINAPI mfsession_Pause(IMFMediaSession *iface)
{
    struct media_session *session = impl_from_IMFMediaSession(iface);

    TRACE("%p.\n", iface);

    return session_submit_simple_command(session, SESSION_CMD_PAUSE);
}

static HRESULT WINAPI mfsession_Stop(IMFMediaSession *iface)
{
    struct media_session *session = impl_from_IMFMediaSession(iface);

    TRACE("%p.\n", iface);

    return session_submit_simple_command(session, SESSION_CMD_STOP);
}

static HRESULT WINAPI mfsession_Close(IMFMediaSession *iface)
{
    struct media_session *session = impl_from_IMFMediaSession(iface);

    TRACE("%p.\n", iface);

    return session_submit_simple_command(session, SESSION_CMD_CLOSE);
}

static HRESULT WINAPI mfsession_Shutdown(IMFMediaSession *iface)
{
    struct media_session *session = impl_from_IMFMediaSession(iface);
    HRESULT hr = S_OK;

    FIXME("%p.\n", iface);

    EnterCriticalSection(&session->cs);
    if (SUCCEEDED(hr = session_is_shut_down(session)))
    {
        session->state = SESSION_STATE_SHUT_DOWN;
        IMFMediaEventQueue_Shutdown(session->event_queue);
        if (session->quality_manager)
            IMFQualityManager_Shutdown(session->quality_manager);
    }
    LeaveCriticalSection(&session->cs);

    return hr;
}

static HRESULT WINAPI mfsession_GetClock(IMFMediaSession *iface, IMFClock **clock)
{
    struct media_session *session = impl_from_IMFMediaSession(iface);
    HRESULT hr;

    TRACE("%p, %p.\n", iface, clock);

    EnterCriticalSection(&session->cs);
    if (SUCCEEDED(hr = session_is_shut_down(session)))
    {
        *clock = (IMFClock *)session->clock;
        IMFClock_AddRef(*clock);
    }
    LeaveCriticalSection(&session->cs);

    return hr;
}

static HRESULT WINAPI mfsession_GetSessionCapabilities(IMFMediaSession *iface, DWORD *caps)
{
    struct media_session *session = impl_from_IMFMediaSession(iface);
    HRESULT hr = S_OK;

    TRACE("%p, %p.\n", iface, caps);

    if (!caps)
        return E_POINTER;

    EnterCriticalSection(&session->cs);
    if (SUCCEEDED(hr = session_is_shut_down(session)))
        *caps = session->caps;
    LeaveCriticalSection(&session->cs);

    return hr;
}

static HRESULT WINAPI mfsession_GetFullTopology(IMFMediaSession *iface, DWORD flags, TOPOID id, IMFTopology **topology)
{
    struct media_session *session = impl_from_IMFMediaSession(iface);
    struct queued_topology *queued;
    TOPOID topo_id;
    HRESULT hr;

    TRACE("%p, %#x, %s, %p.\n", iface, flags, wine_dbgstr_longlong(id), topology);

    *topology = NULL;

    EnterCriticalSection(&session->cs);

    if (SUCCEEDED(hr = session_is_shut_down(session)))
    {
        if (flags & MFSESSION_GETFULLTOPOLOGY_CURRENT)
        {
            if (session->presentation.topo_status != MF_TOPOSTATUS_INVALID)
                *topology = session->presentation.current_topology;
            else
                hr = MF_E_INVALIDREQUEST;
        }
        else
        {
            LIST_FOR_EACH_ENTRY(queued, &session->topologies, struct queued_topology, entry)
            {
                if (SUCCEEDED(IMFTopology_GetTopologyID(queued->topology, &topo_id)) && topo_id == id)
                {
                    *topology = queued->topology;
                    break;
                }
            }
        }

        if (*topology)
            IMFTopology_AddRef(*topology);
    }

    LeaveCriticalSection(&session->cs);

    return hr;
}

static const IMFMediaSessionVtbl mfmediasessionvtbl =
{
    mfsession_QueryInterface,
    mfsession_AddRef,
    mfsession_Release,
    mfsession_GetEvent,
    mfsession_BeginGetEvent,
    mfsession_EndGetEvent,
    mfsession_QueueEvent,
    mfsession_SetTopology,
    mfsession_ClearTopologies,
    mfsession_Start,
    mfsession_Pause,
    mfsession_Stop,
    mfsession_Close,
    mfsession_Shutdown,
    mfsession_GetClock,
    mfsession_GetSessionCapabilities,
    mfsession_GetFullTopology,
};

static HRESULT WINAPI session_get_service_QueryInterface(IMFGetService *iface, REFIID riid, void **obj)
{
    struct media_session *session = impl_from_IMFGetService(iface);
    return IMFMediaSession_QueryInterface(&session->IMFMediaSession_iface, riid, obj);
}

static ULONG WINAPI session_get_service_AddRef(IMFGetService *iface)
{
    struct media_session *session = impl_from_IMFGetService(iface);
    return IMFMediaSession_AddRef(&session->IMFMediaSession_iface);
}

static ULONG WINAPI session_get_service_Release(IMFGetService *iface)
{
    struct media_session *session = impl_from_IMFGetService(iface);
    return IMFMediaSession_Release(&session->IMFMediaSession_iface);
}

static HRESULT WINAPI session_get_service_GetService(IMFGetService *iface, REFGUID service, REFIID riid, void **obj)
{
    struct media_session *session = impl_from_IMFGetService(iface);

    TRACE("%p, %s, %s, %p.\n", iface, debugstr_guid(service), debugstr_guid(riid), obj);

    *obj = NULL;

    if (IsEqualGUID(service, &MF_RATE_CONTROL_SERVICE))
    {
        if (IsEqualIID(riid, &IID_IMFRateSupport))
        {
            *obj = &session->IMFRateSupport_iface;
        }
        else if (IsEqualIID(riid, &IID_IMFRateControl))
        {
            *obj = &session->IMFRateControl_iface;
        }
    }
    else if (IsEqualGUID(service, &MF_LOCAL_MFT_REGISTRATION_SERVICE))
    {
        return IMFLocalMFTRegistration_QueryInterface(&local_mft_registration, riid, obj);
    }
    else
        FIXME("Unsupported service %s.\n", debugstr_guid(service));

    if (*obj)
        IUnknown_AddRef((IUnknown *)*obj);

    return *obj ? S_OK : E_NOINTERFACE;
}

static const IMFGetServiceVtbl session_get_service_vtbl =
{
    session_get_service_QueryInterface,
    session_get_service_AddRef,
    session_get_service_Release,
    session_get_service_GetService,
};

static HRESULT WINAPI session_commands_callback_QueryInterface(IMFAsyncCallback *iface, REFIID riid, void **obj)
{
    if (IsEqualIID(riid, &IID_IMFAsyncCallback) ||
            IsEqualIID(riid, &IID_IUnknown))
    {
        *obj = iface;
        IMFAsyncCallback_AddRef(iface);
        return S_OK;
    }

    WARN("Unsupported %s.\n", debugstr_guid(riid));
    *obj = NULL;
    return E_NOINTERFACE;
}

static ULONG WINAPI session_commands_callback_AddRef(IMFAsyncCallback *iface)
{
    struct media_session *session = impl_from_commands_callback_IMFAsyncCallback(iface);
    return IMFMediaSession_AddRef(&session->IMFMediaSession_iface);
}

static ULONG WINAPI session_commands_callback_Release(IMFAsyncCallback *iface)
{
    struct media_session *session = impl_from_commands_callback_IMFAsyncCallback(iface);
    return IMFMediaSession_Release(&session->IMFMediaSession_iface);
}

static HRESULT WINAPI session_commands_callback_GetParameters(IMFAsyncCallback *iface, DWORD *flags, DWORD *queue)
{
    return E_NOTIMPL;
}

static HRESULT WINAPI session_commands_callback_Invoke(IMFAsyncCallback *iface, IMFAsyncResult *result)
{
    struct session_op *op = impl_op_from_IUnknown(IMFAsyncResult_GetStateNoAddRef(result));
    struct media_session *session = impl_from_commands_callback_IMFAsyncCallback(iface);

    EnterCriticalSection(&session->cs);

    switch (op->command)
    {
        case SESSION_CMD_CLEAR_TOPOLOGIES:
            session_clear_topologies(session);
            IMFMediaEventQueue_QueueEventParamVar(session->event_queue, MESessionTopologiesCleared, &GUID_NULL,
                    S_OK, NULL);
            session_command_complete(session);
            break;
        case SESSION_CMD_SET_TOPOLOGY:
            session_set_topology(session, op->u.set_topology.flags, op->u.set_topology.topology);
            session_command_complete(session);
            break;
        case SESSION_CMD_START:
            session_start(session, &op->u.start.time_format, &op->u.start.start_position);
            break;
        case SESSION_CMD_PAUSE:
            session_pause(session);
            break;
        case SESSION_CMD_STOP:
            session_stop(session);
            break;
        case SESSION_CMD_CLOSE:
            session_close(session);
            break;
        default:
            ;
    }

    LeaveCriticalSection(&session->cs);

    return S_OK;
}

static const IMFAsyncCallbackVtbl session_commands_callback_vtbl =
{
    session_commands_callback_QueryInterface,
    session_commands_callback_AddRef,
    session_commands_callback_Release,
    session_commands_callback_GetParameters,
    session_commands_callback_Invoke,
};

static HRESULT WINAPI session_events_callback_QueryInterface(IMFAsyncCallback *iface, REFIID riid, void **obj)
{
    if (IsEqualIID(riid, &IID_IMFAsyncCallback) ||
            IsEqualIID(riid, &IID_IUnknown))
    {
        *obj = iface;
        IMFAsyncCallback_AddRef(iface);
        return S_OK;
    }

    WARN("Unsupported %s.\n", debugstr_guid(riid));
    *obj = NULL;
    return E_NOINTERFACE;
}

static ULONG WINAPI session_events_callback_AddRef(IMFAsyncCallback *iface)
{
    struct media_session *session = impl_from_events_callback_IMFAsyncCallback(iface);
    return IMFMediaSession_AddRef(&session->IMFMediaSession_iface);
}

static ULONG WINAPI session_events_callback_Release(IMFAsyncCallback *iface)
{
    struct media_session *session = impl_from_events_callback_IMFAsyncCallback(iface);
    return IMFMediaSession_Release(&session->IMFMediaSession_iface);
}

static HRESULT WINAPI session_events_callback_GetParameters(IMFAsyncCallback *iface, DWORD *flags, DWORD *queue)
{
    return E_NOTIMPL;
}

static HRESULT session_add_media_stream(struct media_session *session, IMFMediaSource *source, IMFMediaStream *stream)
{
    struct topo_node *node;
    IMFStreamDescriptor *sd;
    DWORD stream_id = 0;
    HRESULT hr;

    if (FAILED(hr = IMFMediaStream_GetStreamDescriptor(stream, &sd)))
        return hr;

    hr = IMFStreamDescriptor_GetStreamIdentifier(sd, &stream_id);
    IMFStreamDescriptor_Release(sd);
    if (FAILED(hr))
        return hr;

    LIST_FOR_EACH_ENTRY(node, &session->presentation.nodes, struct topo_node, entry)
    {
        if (node->type == MF_TOPOLOGY_SOURCESTREAM_NODE && node->u.source.source == source
                && node->u.source.stream_id == stream_id)
        {
            if (node->object.source_stream)
            {
                WARN("Node already has stream set.\n");
                return S_FALSE;
            }

            node->object.source_stream = stream;
            IMFMediaStream_AddRef(node->object.source_stream);
            break;
        }
    }

    return S_OK;
}

static BOOL session_is_source_nodes_state(struct media_session *session, enum object_state state)
{
    struct media_source *source;
    struct topo_node *node;

    LIST_FOR_EACH_ENTRY(source, &session->presentation.sources, struct media_source, entry)
    {
        if (source->state != state)
            return FALSE;
    }

    LIST_FOR_EACH_ENTRY(node, &session->presentation.nodes, struct topo_node, entry)
    {
        if (node->type == MF_TOPOLOGY_SOURCESTREAM_NODE && node->state != state)
            return FALSE;
    }

    return TRUE;
}

static BOOL session_is_output_nodes_state(struct media_session *session, enum object_state state)
{
    struct topo_node *node;

    LIST_FOR_EACH_ENTRY(node, &session->presentation.nodes, struct topo_node, entry)
    {
        if (node->type == MF_TOPOLOGY_OUTPUT_NODE && node->state != state)
            return FALSE;
    }

    return TRUE;
}

static enum object_state session_get_object_state_for_event(MediaEventType event)
{
    switch (event)
    {
        case MESourceStarted:
        case MEStreamStarted:
        case MEStreamSinkStarted:
            return OBJ_STATE_STARTED;
        case MESourcePaused:
        case MEStreamPaused:
        case MEStreamSinkPaused:
            return OBJ_STATE_PAUSED;
        case MESourceStopped:
        case MEStreamStopped:
        case MEStreamSinkStopped:
            return OBJ_STATE_STOPPED;
        case MEStreamSinkPrerolled:
            return OBJ_STATE_PREROLLED;
        default:
            return OBJ_STATE_INVALID;
    }
}

static void session_set_consumed_clock(IUnknown *object, IMFPresentationClock *clock)
{
    IMFClockConsumer *consumer;

    if (SUCCEEDED(IUnknown_QueryInterface(object, &IID_IMFClockConsumer, (void **)&consumer)))
    {
        IMFClockConsumer_SetPresentationClock(consumer, clock);
        IMFClockConsumer_Release(consumer);
    }
}

static void session_set_presentation_clock(struct media_session *session)
{
    IMFPresentationTimeSource *time_source = NULL;
    struct media_source *source;
    struct media_sink *sink;
    struct topo_node *node;
    HRESULT hr;

    LIST_FOR_EACH_ENTRY(node, &session->presentation.nodes, struct topo_node, entry)
    {
        if (node->type == MF_TOPOLOGY_TRANSFORM_NODE)
            IMFTransform_ProcessMessage(node->object.transform, MFT_MESSAGE_NOTIFY_START_OF_STREAM, 0);
    }

    if (!(session->presentation.flags & SESSION_FLAG_PRESENTATION_CLOCK_SET))
    {
        /* Attempt to get time source from the sinks. */
        LIST_FOR_EACH_ENTRY(sink, &session->presentation.sinks, struct media_sink, entry)
        {
            if (SUCCEEDED(IMFMediaSink_QueryInterface(sink->sink, &IID_IMFPresentationTimeSource,
                    (void **)&time_source)))
                 break;
        }

        if (time_source)
        {
            hr = IMFPresentationClock_SetTimeSource(session->clock, time_source);
            IMFPresentationTimeSource_Release(time_source);
        }
        else
            hr = IMFPresentationClock_SetTimeSource(session->clock, session->system_time_source);

        if (FAILED(hr))
            WARN("Failed to set time source, hr %#x.\n", hr);

        LIST_FOR_EACH_ENTRY(node, &session->presentation.nodes, struct topo_node, entry)
        {
            if (node->type != MF_TOPOLOGY_OUTPUT_NODE)
                continue;

            if (FAILED(hr = IMFStreamSink_BeginGetEvent(node->object.sink_stream, &session->events_callback,
                    node->object.object)))
            {
                WARN("Failed to subscribe to stream sink events, hr %#x.\n", hr);
            }
        }

        /* Set clock for all topology nodes. */
        LIST_FOR_EACH_ENTRY(source, &session->presentation.sources, struct media_source, entry)
        {
            session_set_consumed_clock((IUnknown *)source->source, session->clock);
        }

        LIST_FOR_EACH_ENTRY(sink, &session->presentation.sinks, struct media_sink, entry)
        {
            if (sink->event_generator && FAILED(hr = IMFMediaEventGenerator_BeginGetEvent(sink->event_generator,
                    &session->events_callback, (IUnknown *)sink->event_generator)))
            {
                WARN("Failed to subscribe to sink events, hr %#x.\n", hr);
            }

            if (FAILED(hr = IMFMediaSink_SetPresentationClock(sink->sink, session->clock)))
                WARN("Failed to set presentation clock for the sink, hr %#x.\n", hr);
        }

        LIST_FOR_EACH_ENTRY(node, &session->presentation.nodes, struct topo_node, entry)
        {
            if (node->type != MF_TOPOLOGY_TRANSFORM_NODE)
                continue;

            session_set_consumed_clock(node->object.object, session->clock);
        }

        session->presentation.flags |= SESSION_FLAG_PRESENTATION_CLOCK_SET;
    }
}

static HRESULT session_start_clock(struct media_session *session)
{
    LONGLONG start_offset = 0;
    HRESULT hr;

    if (IsEqualGUID(&session->presentation.time_format, &GUID_NULL))
    {
        if (session->presentation.start_position.vt == VT_EMPTY)
            start_offset = PRESENTATION_CURRENT_POSITION;
        else if (session->presentation.start_position.vt == VT_I8)
            start_offset = session->presentation.start_position.hVal.QuadPart;
        else
            FIXME("Unhandled position type %d.\n", session->presentation.start_position.vt);
    }
    else
        FIXME("Unhandled time format %s.\n", debugstr_guid(&session->presentation.time_format));

    if (FAILED(hr = IMFPresentationClock_Start(session->clock, start_offset)))
        WARN("Failed to start session clock, hr %#x.\n", hr);

    return hr;
}

static struct topo_node *session_get_node_object(struct media_session *session, IUnknown *object,
        MF_TOPOLOGY_TYPE node_type)
{
    struct topo_node *node = NULL;

    LIST_FOR_EACH_ENTRY(node, &session->presentation.nodes, struct topo_node, entry)
    {
        if (node->type == node_type && object == node->object.object)
            break;
    }

    return node;
}

static BOOL session_set_node_object_state(struct media_session *session, IUnknown *object,
        MF_TOPOLOGY_TYPE node_type, enum object_state state)
{
    struct topo_node *node;
    BOOL changed = FALSE;

    if ((node = session_get_node_object(session, object, node_type)))
    {
        changed = node->state != state;
        node->state = state;
    }

    return changed;
}

static void session_set_source_object_state(struct media_session *session, IUnknown *object,
        MediaEventType event_type)
{
    IMFStreamSink *stream_sink;
    struct media_source *src;
    struct media_sink *sink;
    enum object_state state;
    struct topo_node *node;
    unsigned int i, count;
    BOOL changed = FALSE;
    HRESULT hr;

    if ((state = session_get_object_state_for_event(event_type)) == OBJ_STATE_INVALID)
        return;

    switch (event_type)
    {
        case MESourceStarted:
        case MESourcePaused:
        case MESourceStopped:

            LIST_FOR_EACH_ENTRY(src, &session->presentation.sources, struct media_source, entry)
            {
                if (object == (IUnknown *)src->source)
                {
                    changed = src->state != state;
                    src->state = state;
                    break;
                }
            }
            break;
        case MEStreamStarted:
        case MEStreamPaused:
        case MEStreamStopped:

            changed = session_set_node_object_state(session, object, MF_TOPOLOGY_SOURCESTREAM_NODE, state);
        default:
            ;
    }

    if (!changed)
        return;

    switch (session->state)
    {
        case SESSION_STATE_STARTING_SOURCES:
            if (!session_is_source_nodes_state(session, OBJ_STATE_STARTED))
                break;

            session_set_topo_status(session, S_OK, MF_TOPOSTATUS_STARTED_SOURCE);

            session_set_presentation_clock(session);

            if (session->presentation.flags & SESSION_FLAG_NEEDS_PREROLL)
            {
                MFTIME preroll_time = 0;

                if (session->presentation.start_position.vt == VT_I8)
                    preroll_time = session->presentation.start_position.hVal.QuadPart;

                /* Mark stream sinks without prerolling support as PREROLLED to keep state test logic generic. */
                LIST_FOR_EACH_ENTRY(sink, &session->presentation.sinks, struct media_sink, entry)
                {
                    if (sink->preroll)
                    {
                        /* FIXME: abort and enter error state on failure. */
                        if (FAILED(hr = IMFMediaSinkPreroll_NotifyPreroll(sink->preroll, preroll_time)))
                            WARN("Preroll notification failed, hr %#x.\n", hr);
                    }
                    else
                    {
                        if (SUCCEEDED(IMFMediaSink_GetStreamSinkCount(sink->sink, &count)))
                        {
                            for (i = 0; i < count; ++i)
                            {
                                if (SUCCEEDED(IMFMediaSink_GetStreamSinkByIndex(sink->sink, i, &stream_sink)))
                                {
                                    session_set_node_object_state(session, (IUnknown *)stream_sink, MF_TOPOLOGY_OUTPUT_NODE,
                                            OBJ_STATE_PREROLLED);
                                    IMFStreamSink_Release(stream_sink);
                                }
                            }
                        }
                    }
                }
                session->state = SESSION_STATE_PREROLLING_SINKS;
            }
            else if (SUCCEEDED(session_start_clock(session)))
                session->state = SESSION_STATE_STARTING_SINKS;

            break;
        case SESSION_STATE_PAUSING_SOURCES:
            if (!session_is_source_nodes_state(session, OBJ_STATE_PAUSED))
                break;

            session_set_paused(session, S_OK);
            break;
        case SESSION_STATE_STOPPING_SOURCES:
            if (!session_is_source_nodes_state(session, OBJ_STATE_STOPPED))
                break;

            LIST_FOR_EACH_ENTRY(node, &session->presentation.nodes, struct topo_node, entry)
            {
                switch (node->type)
                {
                    case MF_TOPOLOGY_OUTPUT_NODE:
                        IMFStreamSink_Flush(node->object.sink_stream);
                        break;
                    case MF_TOPOLOGY_TRANSFORM_NODE:
                        IMFTransform_ProcessMessage(node->object.transform, MFT_MESSAGE_COMMAND_FLUSH, 0);
                        break;
                    default:
                        ;
                }
            }

            session_set_caps(session, session->caps & ~MFSESSIONCAP_PAUSE);

            if (session->presentation.flags & SESSION_FLAG_FINALIZE_SINKS)
                session_finalize_sinks(session);
            else
                session_set_stopped(session, S_OK);

            break;
        default:
            ;
    }
}

static void session_set_sink_stream_state(struct media_session *session, IMFStreamSink *stream,
        MediaEventType event_type)
{
    struct media_source *source;
    enum object_state state;
    HRESULT hr = S_OK;
    BOOL changed;

    if ((state = session_get_object_state_for_event(event_type)) == OBJ_STATE_INVALID)
        return;

    if (!(changed = session_set_node_object_state(session, (IUnknown *)stream, MF_TOPOLOGY_OUTPUT_NODE, state)))
        return;

    switch (session->state)
    {
        case SESSION_STATE_PREROLLING_SINKS:
            if (!session_is_output_nodes_state(session, OBJ_STATE_PREROLLED))
                break;

            if (SUCCEEDED(session_start_clock(session)))
                session->state = SESSION_STATE_STARTING_SINKS;
            break;
        case SESSION_STATE_STARTING_SINKS:
            if (!session_is_output_nodes_state(session, OBJ_STATE_STARTED))
                break;

            session_set_started(session);
            break;
        case SESSION_STATE_PAUSING_SINKS:
            if (!session_is_output_nodes_state(session, OBJ_STATE_PAUSED))
                break;

            session->state = SESSION_STATE_PAUSING_SOURCES;

            LIST_FOR_EACH_ENTRY(source, &session->presentation.sources, struct media_source, entry)
            {
                if (FAILED(hr = IMFMediaSource_Pause(source->source)))
                    break;
            }

            if (FAILED(hr))
                session_set_paused(session, hr);

            break;
        case SESSION_STATE_STOPPING_SINKS:
            if (!session_is_output_nodes_state(session, OBJ_STATE_STOPPED))
                break;

            session->state = SESSION_STATE_STOPPING_SOURCES;

            LIST_FOR_EACH_ENTRY(source, &session->presentation.sources, struct media_source, entry)
            {
                if (session->presentation.flags & SESSION_FLAG_END_OF_PRESENTATION)
                    IMFMediaSource_Stop(source->source);
                else if (FAILED(hr = IMFMediaSource_Stop(source->source)))
                    break;
            }

            if (session->presentation.flags & SESSION_FLAG_END_OF_PRESENTATION || FAILED(hr))
                session_set_stopped(session, hr);

            break;
        default:
            ;
    }
}

static struct topo_node *session_get_node_by_id(struct media_session *session, TOPOID id)
{
    struct topo_node *node;

    LIST_FOR_EACH_ENTRY(node, &session->presentation.nodes, struct topo_node, entry)
    {
        if (node->node_id == id)
            return node;
    }

    return NULL;
}

static DWORD transform_node_get_stream_id(struct topo_node *node, BOOL output, DWORD index)
{
    unsigned int *map = output ? node->u.transform.output_map : node->u.transform.input_map;
    return map ? map[index] : index;
}

static struct sample *transform_create_sample(IMFSample *sample)
{
    struct sample *sample_entry = heap_alloc_zero(sizeof(*sample_entry));

    if (sample_entry)
    {
        sample_entry->sample = sample;
        if (sample_entry->sample)
            IMFSample_AddRef(sample_entry->sample);
    }

    return sample_entry;
}

static HRESULT transform_node_pull_samples(struct topo_node *node)
{
    MFT_OUTPUT_STREAM_INFO stream_info;
    MFT_OUTPUT_DATA_BUFFER *buffers;
    struct sample *queued_sample;
    DWORD status = 0;
    unsigned int i;
    HRESULT hr;

    if (!(buffers = heap_calloc(node->u.transform.output_count, sizeof(*buffers))))
        return E_OUTOFMEMORY;

    for (i = 0; i < node->u.transform.output_count; ++i)
    {
        buffers[i].dwStreamID = transform_node_get_stream_id(node, TRUE, i);
        buffers[i].pSample = NULL;
        buffers[i].dwStatus = 0;
        buffers[i].pEvents = NULL;

        memset(&stream_info, 0, sizeof(stream_info));
        if (FAILED(hr = IMFTransform_GetOutputStreamInfo(node->object.transform, buffers[i].dwStreamID, &stream_info)))
            break;

        if (!(stream_info.dwFlags & MFT_OUTPUT_STREAM_PROVIDES_SAMPLES))
        {
            IMFMediaBuffer *buffer = NULL;

            hr = MFCreateAlignedMemoryBuffer(stream_info.cbSize, stream_info.cbAlignment, &buffer);
            if (SUCCEEDED(hr))
                hr = MFCreateSample(&buffers[i].pSample);

            if (SUCCEEDED(hr))
                hr = IMFSample_AddBuffer(buffers[i].pSample, buffer);

            if (buffer)
                IMFMediaBuffer_Release(buffer);

            if (FAILED(hr))
                break;
        }
    }

    if (SUCCEEDED(hr))
        hr = IMFTransform_ProcessOutput(node->object.transform, 0, node->u.transform.output_count, buffers, &status);

    /* Collect returned samples for all streams. */
    for (i = 0; i < node->u.transform.output_count; ++i)
    {
        if (buffers[i].pEvents)
            IMFCollection_Release(buffers[i].pEvents);

        if (SUCCEEDED(hr) && !(buffers[i].dwStatus & MFT_OUTPUT_DATA_BUFFER_NO_SAMPLE))
        {
            queued_sample = transform_create_sample(buffers[i].pSample);
            list_add_tail(&node->u.transform.outputs[i].samples, &queued_sample->entry);
        }

        if (buffers[i].pSample)
            IMFSample_Release(buffers[i].pSample);
    }

    heap_free(buffers);

    return hr;
}

static void session_deliver_sample_to_node(struct media_session *session, IMFTopologyNode *node, unsigned int input,
        IMFSample *sample)
{
    struct sample *sample_entry, *sample_entry2;
    DWORD stream_id, downstream_input;
    IMFTopologyNode *downstream_node;
    struct topo_node *topo_node;
    MF_TOPOLOGY_TYPE node_type;
    BOOL drain = FALSE;
    TOPOID node_id;
    unsigned int i;
    HRESULT hr;

    IMFTopologyNode_GetNodeType(node, &node_type);
    IMFTopologyNode_GetTopoNodeID(node, &node_id);

    topo_node = session_get_node_by_id(session, node_id);

    switch (node_type)
    {
        case MF_TOPOLOGY_OUTPUT_NODE:
            if (sample)
            {
                if (topo_node->u.sink.requests)
                {
                    if (FAILED(hr = IMFStreamSink_ProcessSample(topo_node->object.sink_stream, sample)))
                        WARN("Stream sink failed to process sample, hr %#x.\n", hr);
                    topo_node->u.sink.requests--;
                }
            }
            else if (FAILED(hr = IMFStreamSink_PlaceMarker(topo_node->object.sink_stream, MFSTREAMSINK_MARKER_ENDOFSEGMENT,
                    NULL, NULL)))
            {
                WARN("Failed to place sink marker, hr %#x.\n", hr);
            }
            break;
        case MF_TOPOLOGY_TRANSFORM_NODE:

            transform_node_pull_samples(topo_node);

            sample_entry = transform_create_sample(sample);
            list_add_tail(&topo_node->u.transform.inputs[input].samples, &sample_entry->entry);

            for (i = 0; i < topo_node->u.transform.input_count; ++i)
            {
                stream_id = transform_node_get_stream_id(topo_node, FALSE, i);
                LIST_FOR_EACH_ENTRY_SAFE(sample_entry, sample_entry2, &topo_node->u.transform.inputs[i].samples,
                        struct sample, entry)
                {
                    if (sample_entry->sample)
                    {
                        if ((hr = IMFTransform_ProcessInput(topo_node->object.transform, stream_id,
                                sample_entry->sample, 0)) == MF_E_NOTACCEPTING)
                            break;
                        if (FAILED(hr))
                            WARN("Failed to process input for stream %u/%u, hr %#x.\n", i, stream_id, hr);
                        transform_release_sample(sample_entry);
                    }
                    else
                    {
                        transform_stream_drop_samples(&topo_node->u.transform.inputs[i]);
                        drain = TRUE;
                    }
                }
            }

            if (drain)
            {
                if (FAILED(hr = IMFTransform_ProcessMessage(topo_node->object.transform, MFT_MESSAGE_COMMAND_DRAIN, 0)))
                    WARN("Drain command failed for transform, hr %#x.\n", hr);
            }

            transform_node_pull_samples(topo_node);

            /* Remaining unprocessed input has been discarded, now queue markers for every output. */
            if (drain)
            {
                for (i = 0; i < topo_node->u.transform.output_count; ++i)
                {
                     if ((sample_entry = transform_create_sample(NULL)))
                         list_add_tail(&topo_node->u.transform.outputs[i].samples, &sample_entry->entry);
                }
            }

            /* Push down all available output. */
            for (i = 0; i < topo_node->u.transform.output_count; ++i)
            {
                if (FAILED(IMFTopologyNode_GetOutput(node, i, &downstream_node, &downstream_input)))
                {
                    WARN("Failed to get connected node for output %u.\n", i);
                    continue;
                }

                LIST_FOR_EACH_ENTRY_SAFE(sample_entry, sample_entry2, &topo_node->u.transform.outputs[i].samples,
                        struct sample, entry)
                {
                    if (!topo_node->u.transform.outputs[i].requests)
                        break;

                    session_deliver_sample_to_node(session, downstream_node, downstream_input, sample_entry->sample);
                    topo_node->u.transform.outputs[i].requests--;

                    transform_release_sample(sample_entry);
                }

                IMFTopologyNode_Release(downstream_node);
            }

            break;
        case MF_TOPOLOGY_TEE_NODE:
            FIXME("Unhandled downstream node type %d.\n", node_type);
            break;
        default:
            ;
    }
}

static HRESULT session_request_sample_from_node(struct media_session *session, IMFTopologyNode *node, DWORD output)
{
    IMFTopologyNode *downstream_node, *upstream_node;
    unsigned int downstream_input, upstream_output;
    struct topo_node *topo_node;
    MF_TOPOLOGY_TYPE node_type;
    struct sample *sample;
    TOPOID node_id;
    HRESULT hr;

    IMFTopologyNode_GetNodeType(node, &node_type);
    IMFTopologyNode_GetTopoNodeID(node, &node_id);

    topo_node = session_get_node_by_id(session, node_id);

    switch (node_type)
    {
        case MF_TOPOLOGY_SOURCESTREAM_NODE:
            if (FAILED(hr = IMFMediaStream_RequestSample(topo_node->object.source_stream, NULL)))
                WARN("Sample request failed, hr %#x.\n", hr);
            break;
        case MF_TOPOLOGY_TRANSFORM_NODE:

            if (list_empty(&topo_node->u.transform.outputs[output].samples))
            {
                /* Forward request to upstream node. */
                if (SUCCEEDED(hr = IMFTopologyNode_GetInput(node, 0 /* FIXME */, &upstream_node, &upstream_output)))
                {
                    if (SUCCEEDED(hr = session_request_sample_from_node(session, upstream_node, upstream_output)))
                        topo_node->u.transform.outputs[output].requests++;
                    IMFTopologyNode_Release(upstream_node);
                }
            }
            else
            {
                if (SUCCEEDED(hr = IMFTopologyNode_GetOutput(node, output, &downstream_node, &downstream_input)))
                {
                    sample = LIST_ENTRY(list_head(&topo_node->u.transform.outputs[output].samples), struct sample, entry);
                    session_deliver_sample_to_node(session, downstream_node, downstream_input, sample->sample);
                    transform_release_sample(sample);
                    IMFTopologyNode_Release(downstream_node);
                }
            }

            break;
        case MF_TOPOLOGY_TEE_NODE:
            FIXME("Unhandled upstream node type %d.\n", node_type);
        default:
            hr = E_UNEXPECTED;
    }

    return hr;
}

static void session_request_sample(struct media_session *session, IMFStreamSink *sink_stream)
{
    struct topo_node *sink_node = NULL, *node;
    IMFTopologyNode *upstream_node;
    DWORD upstream_output;
    HRESULT hr;

    LIST_FOR_EACH_ENTRY(node, &session->presentation.nodes, struct topo_node, entry)
    {
        if (node->type == MF_TOPOLOGY_OUTPUT_NODE && node->object.sink_stream == sink_stream)
        {
            sink_node = node;
            break;
        }
    }

    if (!sink_node)
        return;

    if (FAILED(hr = IMFTopologyNode_GetInput(sink_node->node, 0, &upstream_node, &upstream_output)))
    {
        WARN("Failed to get upstream node connection, hr %#x.\n", hr);
        return;
    }

    if (SUCCEEDED(session_request_sample_from_node(session, upstream_node, upstream_output)))
        sink_node->u.sink.requests++;
    IMFTopologyNode_Release(upstream_node);
}

static void session_deliver_sample(struct media_session *session, IMFMediaStream *stream, const PROPVARIANT *value)
{
    struct topo_node *source_node = NULL, *node;
    IMFTopologyNode *downstream_node;
    DWORD downstream_input;
    HRESULT hr;

    if (value && (value->vt != VT_UNKNOWN || !value->punkVal))
    {
        WARN("Unexpected value type %d.\n", value->vt);
        return;
    }

    LIST_FOR_EACH_ENTRY(node, &session->presentation.nodes, struct topo_node, entry)
    {
        if (node->type == MF_TOPOLOGY_SOURCESTREAM_NODE && node->object.source_stream == stream)
        {
            source_node = node;
            break;
        }
    }

    if (!source_node)
        return;

    if (!value)
        source_node->flags |= TOPO_NODE_END_OF_STREAM;

    if (FAILED(hr = IMFTopologyNode_GetOutput(source_node->node, 0, &downstream_node, &downstream_input)))
    {
        WARN("Failed to get downstream node connection, hr %#x.\n", hr);
        return;
    }

    session_deliver_sample_to_node(session, downstream_node, downstream_input, value ? (IMFSample *)value->punkVal : NULL);
    IMFTopologyNode_Release(downstream_node);
}

static void session_sink_invalidated(struct media_session *session, IMFMediaEvent *event, IMFStreamSink *sink)
{
    struct topo_node *node, *sink_node = NULL;
    HRESULT hr;

    LIST_FOR_EACH_ENTRY(node, &session->presentation.nodes, struct topo_node, entry)
    {
        if (node->type == MF_TOPOLOGY_OUTPUT_NODE && node->object.sink_stream == sink)
        {
            sink_node = node;
            break;
        }
    }

    if (!sink_node)
        return;

    if (!event)
    {
        if (FAILED(hr = MFCreateMediaEvent(MESinkInvalidated, &GUID_NULL, S_OK, NULL, &event)))
            WARN("Failed to create event, hr %#x.\n", hr);
    }

    if (!event)
        return;

    IMFMediaEvent_SetUINT64(event, &MF_EVENT_OUTPUT_NODE, sink_node->node_id);
    IMFMediaEventQueue_QueueEvent(session->event_queue, event);

    session_set_topo_status(session, S_OK, MF_TOPOSTATUS_ENDED);
}

static BOOL session_nodes_is_mask_set(struct media_session *session, MF_TOPOLOGY_TYPE node_type, unsigned int flags)
{
    struct media_source *source;
    struct topo_node *node;

    if (node_type == MF_TOPOLOGY_MAX)
    {
        LIST_FOR_EACH_ENTRY(source, &session->presentation.sources, struct media_source, entry)
        {
            if ((source->flags & flags) != flags)
                return FALSE;
        }
    }
    else
    {
        LIST_FOR_EACH_ENTRY(node, &session->presentation.nodes, struct topo_node, entry)
        {
            if (node->type == node_type && (node->flags & flags) != flags)
                return FALSE;
        }
    }

    return TRUE;
}

static void session_raise_end_of_presentation(struct media_session *session)
{
    if (!(session_nodes_is_mask_set(session, MF_TOPOLOGY_SOURCESTREAM_NODE, TOPO_NODE_END_OF_STREAM)))
        return;

    if (!(session->presentation.flags & SESSION_FLAG_END_OF_PRESENTATION))
    {
        if (session_nodes_is_mask_set(session, MF_TOPOLOGY_MAX, SOURCE_FLAG_END_OF_PRESENTATION))
        {
            session->presentation.flags |= SESSION_FLAG_END_OF_PRESENTATION;
            session_push_back_command(session, SESSION_CMD_END);
            IMFMediaEventQueue_QueueEventParamVar(session->event_queue, MEEndOfPresentation, &GUID_NULL, S_OK, NULL);
        }
    }
}

static void session_handle_end_of_stream(struct media_session *session, IMFMediaStream *stream)
{
    struct topo_node *node;

    if (!(node = session_get_node_object(session, (IUnknown *)stream, MF_TOPOLOGY_SOURCESTREAM_NODE))
            || node->flags & TOPO_NODE_END_OF_STREAM)
    {
        return;
    }

    session_deliver_sample(session, stream, NULL);

    session_raise_end_of_presentation(session);
}

static void session_handle_end_of_presentation(struct media_session *session, IMFMediaSource *object)
{
    struct media_source *source;

    LIST_FOR_EACH_ENTRY(source, &session->presentation.sources, struct media_source, entry)
    {
        if (source->source == object)
        {
            if (!(source->flags & SOURCE_FLAG_END_OF_PRESENTATION))
            {
                source->flags |= SOURCE_FLAG_END_OF_PRESENTATION;
                session_raise_end_of_presentation(session);
            }

            break;
        }
    }
}

static void session_sink_stream_marker(struct media_session *session, IMFStreamSink *stream_sink)
{
    struct topo_node *node;

    if (!(node = session_get_node_object(session, (IUnknown *)stream_sink, MF_TOPOLOGY_OUTPUT_NODE))
            || node->flags & TOPO_NODE_END_OF_STREAM)
    {
        return;
    }

    node->flags |= TOPO_NODE_END_OF_STREAM;

    if (session->presentation.flags & SESSION_FLAG_END_OF_PRESENTATION &&
            session_nodes_is_mask_set(session, MF_TOPOLOGY_OUTPUT_NODE, TOPO_NODE_END_OF_STREAM))
    {
        session_set_topo_status(session, S_OK, MF_TOPOSTATUS_ENDED);
        session_set_caps(session, session->caps & ~MFSESSIONCAP_PAUSE);
        session_stop(session);
    }
}

static HRESULT WINAPI session_events_callback_Invoke(IMFAsyncCallback *iface, IMFAsyncResult *result)
{
    struct media_session *session = impl_from_events_callback_IMFAsyncCallback(iface);
    IMFMediaEventGenerator *event_source;
    IMFMediaEvent *event = NULL;
    MediaEventType event_type;
    IMFMediaSource *source;
    IMFMediaStream *stream;
    PROPVARIANT value;
    HRESULT hr;

    if (FAILED(hr = IMFAsyncResult_GetState(result, (IUnknown **)&event_source)))
        return hr;

    if (FAILED(hr = IMFMediaEventGenerator_EndGetEvent(event_source, result, &event)))
    {
        WARN("Failed to get event from %p, hr %#x.\n", event_source, hr);
        goto failed;
    }

    if (FAILED(hr = IMFMediaEvent_GetType(event, &event_type)))
    {
        WARN("Failed to get event type, hr %#x.\n", hr);
        goto failed;
    }

    value.vt = VT_EMPTY;
    if (FAILED(hr = IMFMediaEvent_GetValue(event, &value)))
    {
        WARN("Failed to get event value, hr %#x.\n", hr);
        goto failed;
    }

    switch (event_type)
    {
        case MESourceStarted:
        case MESourcePaused:
        case MESourceStopped:
        case MEStreamStarted:
        case MEStreamPaused:
        case MEStreamStopped:

            EnterCriticalSection(&session->cs);
            session_set_source_object_state(session, (IUnknown *)event_source, event_type);
            LeaveCriticalSection(&session->cs);

            break;

        case MEBufferingStarted:
        case MEBufferingStopped:

            EnterCriticalSection(&session->cs);
            if (session_get_media_source(session, (IMFMediaSource *)event_source))
            {
                if (event_type == MEBufferingStarted)
                    IMFPresentationClock_Pause(session->clock);
                else
                    IMFPresentationClock_Start(session->clock, PRESENTATION_CURRENT_POSITION);

                IMFMediaEventQueue_QueueEvent(session->event_queue, event);
            }
            LeaveCriticalSection(&session->cs);
            break;

        case MENewStream:
            stream = (IMFMediaStream *)value.punkVal;

            if (value.vt != VT_UNKNOWN || !stream)
            {
                WARN("Unexpected event value.\n");
                break;
            }

            if (FAILED(hr = IMFMediaStream_GetMediaSource(stream, &source)))
                break;

            EnterCriticalSection(&session->cs);
            if (SUCCEEDED(hr = session_add_media_stream(session, source, stream)))
                hr = IMFMediaStream_BeginGetEvent(stream, &session->events_callback, (IUnknown *)stream);
            LeaveCriticalSection(&session->cs);

            IMFMediaSource_Release(source);

            break;
        case MEStreamSinkStarted:
        case MEStreamSinkPaused:
        case MEStreamSinkStopped:
        case MEStreamSinkPrerolled:

            EnterCriticalSection(&session->cs);
            session_set_sink_stream_state(session, (IMFStreamSink *)event_source, event_type);
            LeaveCriticalSection(&session->cs);

            break;
        case MEStreamSinkMarker:

            EnterCriticalSection(&session->cs);
            session_sink_stream_marker(session, (IMFStreamSink *)event_source);
            LeaveCriticalSection(&session->cs);

            break;
        case MEStreamSinkRequestSample:

            EnterCriticalSection(&session->cs);
            session_request_sample(session, (IMFStreamSink *)event_source);
            LeaveCriticalSection(&session->cs);

            break;
        case MEMediaSample:

            EnterCriticalSection(&session->cs);
            session_deliver_sample(session, (IMFMediaStream *)event_source, &value);
            LeaveCriticalSection(&session->cs);

            break;
        case MEEndOfStream:

            EnterCriticalSection(&session->cs);
            session_handle_end_of_stream(session, (IMFMediaStream *)event_source);
            LeaveCriticalSection(&session->cs);

            break;

        case MEEndOfPresentation:

            EnterCriticalSection(&session->cs);
            session_handle_end_of_presentation(session, (IMFMediaSource *)event_source);
            LeaveCriticalSection(&session->cs);

            break;
        case MEAudioSessionGroupingParamChanged:
        case MEAudioSessionIconChanged:
        case MEAudioSessionNameChanged:
        case MEAudioSessionVolumeChanged:

            IMFMediaEventQueue_QueueEvent(session->event_queue, event);

            break;
        case MEAudioSessionDeviceRemoved:
        case MEAudioSessionDisconnected:
        case MEAudioSessionExclusiveModeOverride:
        case MEAudioSessionFormatChanged:
        case MEAudioSessionServerShutdown:

            IMFMediaEventQueue_QueueEvent(session->event_queue, event);
            /* fallthrough */
        case MESinkInvalidated:

            EnterCriticalSection(&session->cs);
            session_sink_invalidated(session, event_type == MESinkInvalidated ? event : NULL,
                    (IMFStreamSink *)event_source);
            LeaveCriticalSection(&session->cs);

            break;
        default:
            ;
    }

    PropVariantClear(&value);

failed:
    if (event)
        IMFMediaEvent_Release(event);

    if (FAILED(hr = IMFMediaEventGenerator_BeginGetEvent(event_source, iface, (IUnknown *)event_source)))
        WARN("Failed to re-subscribe, hr %#x.\n", hr);

    IMFMediaEventGenerator_Release(event_source);

    return hr;
}

static const IMFAsyncCallbackVtbl session_events_callback_vtbl =
{
    session_events_callback_QueryInterface,
    session_events_callback_AddRef,
    session_events_callback_Release,
    session_events_callback_GetParameters,
    session_events_callback_Invoke,
};

static HRESULT WINAPI session_sink_finalizer_callback_QueryInterface(IMFAsyncCallback *iface, REFIID riid, void **obj)
{
    if (IsEqualIID(riid, &IID_IMFAsyncCallback) ||
            IsEqualIID(riid, &IID_IUnknown))
    {
        *obj = iface;
        IMFAsyncCallback_AddRef(iface);
        return S_OK;
    }

    WARN("Unsupported %s.\n", debugstr_guid(riid));
    *obj = NULL;
    return E_NOINTERFACE;
}

static ULONG WINAPI session_sink_finalizer_callback_AddRef(IMFAsyncCallback *iface)
{
    struct media_session *session = impl_from_sink_finalizer_callback_IMFAsyncCallback(iface);
    return IMFMediaSession_AddRef(&session->IMFMediaSession_iface);
}

static ULONG WINAPI session_sink_finalizer_callback_Release(IMFAsyncCallback *iface)
{
    struct media_session *session = impl_from_sink_finalizer_callback_IMFAsyncCallback(iface);
    return IMFMediaSession_Release(&session->IMFMediaSession_iface);
}

static HRESULT WINAPI session_sink_finalizer_callback_GetParameters(IMFAsyncCallback *iface, DWORD *flags, DWORD *queue)
{
    return E_NOTIMPL;
}

static HRESULT WINAPI session_sink_finalizer_callback_Invoke(IMFAsyncCallback *iface, IMFAsyncResult *result)
{
    struct media_session *session = impl_from_sink_finalizer_callback_IMFAsyncCallback(iface);
    IMFFinalizableMediaSink *fin_sink = NULL;
    BOOL sinks_finalized = TRUE;
    struct media_sink *sink;
    IUnknown *state;
    HRESULT hr;

    if (FAILED(hr = IMFAsyncResult_GetState(result, &state)))
        return hr;

    EnterCriticalSection(&session->cs);

    LIST_FOR_EACH_ENTRY(sink, &session->presentation.sinks, struct media_sink, entry)
    {
        if (state == (IUnknown *)sink->sink)
        {
            if (FAILED(hr = IMFMediaSink_QueryInterface(sink->sink, &IID_IMFFinalizableMediaSink, (void **)&fin_sink)))
                WARN("Unexpected, missing IMFFinalizableSink, hr %#x.\n", hr);
        }
        else
        {
            sinks_finalized &= sink->finalized;
            if (!sinks_finalized)
                break;
        }
    }

    IUnknown_Release(state);

    if (fin_sink)
    {
        /* Complete session transition, or close prematurely on error. */
        if (SUCCEEDED(hr = IMFFinalizableMediaSink_EndFinalize(fin_sink, result)))
        {
            sink->finalized = TRUE;
            if (sinks_finalized)
                session_set_closed(session, hr);
        }
        IMFFinalizableMediaSink_Release(fin_sink);
    }

    LeaveCriticalSection(&session->cs);

    return S_OK;
}

static const IMFAsyncCallbackVtbl session_sink_finalizer_callback_vtbl =
{
    session_sink_finalizer_callback_QueryInterface,
    session_sink_finalizer_callback_AddRef,
    session_sink_finalizer_callback_Release,
    session_sink_finalizer_callback_GetParameters,
    session_sink_finalizer_callback_Invoke,
};

static HRESULT WINAPI session_rate_support_QueryInterface(IMFRateSupport *iface, REFIID riid, void **obj)
{
    struct media_session *session = impl_session_from_IMFRateSupport(iface);
    return IMFMediaSession_QueryInterface(&session->IMFMediaSession_iface, riid, obj);
}

static ULONG WINAPI session_rate_support_AddRef(IMFRateSupport *iface)
{
    struct media_session *session = impl_session_from_IMFRateSupport(iface);
    return IMFMediaSession_AddRef(&session->IMFMediaSession_iface);
}

static ULONG WINAPI session_rate_support_Release(IMFRateSupport *iface)
{
    struct media_session *session = impl_session_from_IMFRateSupport(iface);
    return IMFMediaSession_Release(&session->IMFMediaSession_iface);
}

static HRESULT session_presentation_object_get_rate(IUnknown *object, MFRATE_DIRECTION direction,
        BOOL thin, BOOL fastest, float *result)
{
    IMFRateSupport *rate_support;
    float rate;
    HRESULT hr;

    /* For objects that don't support rate control, it's assumed that only forward direction is allowed, at 1.0f. */

    if (FAILED(hr = MFGetService(object, &MF_RATE_CONTROL_SERVICE, &IID_IMFRateSupport, (void **)&rate_support)))
    {
        if (direction == MFRATE_FORWARD)
        {
            *result = 1.0f;
            return S_OK;
        }
        else
            return MF_E_REVERSE_UNSUPPORTED;
    }

    rate = 0.0f;
    if (fastest)
    {
        if (SUCCEEDED(hr = IMFRateSupport_GetFastestRate(rate_support, direction, thin, &rate)))
            *result = min(fabsf(rate), *result);
    }
    else
    {
        if (SUCCEEDED(hr = IMFRateSupport_GetSlowestRate(rate_support, direction, thin, &rate)))
            *result = max(fabsf(rate), *result);
    }

    IMFRateSupport_Release(rate_support);

    return hr;
}

static HRESULT session_get_presentation_rate(struct media_session *session, MFRATE_DIRECTION direction,
        BOOL thin, BOOL fastest, float *result)
{
    struct media_source *source;
    struct media_sink *sink;
    HRESULT hr = E_POINTER;

    *result = 0.0f;

    EnterCriticalSection(&session->cs);

    if (session->presentation.topo_status != MF_TOPOSTATUS_INVALID)
    {
        LIST_FOR_EACH_ENTRY(source, &session->presentation.sources, struct media_source, entry)
        {
            if (FAILED(hr = session_presentation_object_get_rate((IUnknown *)source->source, direction, thin, fastest, result)))
                break;
        }

        if (SUCCEEDED(hr))
        {
            LIST_FOR_EACH_ENTRY(sink, &session->presentation.sinks, struct media_sink, entry)
            {
                if (FAILED(hr = session_presentation_object_get_rate((IUnknown *)sink->sink, direction, thin, fastest, result)))
                    break;
            }
        }
    }

    LeaveCriticalSection(&session->cs);

    return hr;
}

static HRESULT WINAPI session_rate_support_GetSlowestRate(IMFRateSupport *iface, MFRATE_DIRECTION direction,
        BOOL thin, float *rate)
{
    struct media_session *session = impl_session_from_IMFRateSupport(iface);

    TRACE("%p, %d, %d, %p.\n", iface, direction, thin, rate);

    return session_get_presentation_rate(session, direction, thin, FALSE, rate);
}

static HRESULT WINAPI session_rate_support_GetFastestRate(IMFRateSupport *iface, MFRATE_DIRECTION direction,
        BOOL thin, float *rate)
{
    struct media_session *session = impl_session_from_IMFRateSupport(iface);

    TRACE("%p, %d, %d, %p.\n", iface, direction, thin, rate);

    return session_get_presentation_rate(session, direction, thin, TRUE, rate);
}

static HRESULT WINAPI session_rate_support_IsRateSupported(IMFRateSupport *iface, BOOL thin, float rate,
        float *nearest_supported_rate)
{
    FIXME("%p, %d, %f, %p.\n", iface, thin, rate, nearest_supported_rate);

    return E_NOTIMPL;
}

static const IMFRateSupportVtbl session_rate_support_vtbl =
{
    session_rate_support_QueryInterface,
    session_rate_support_AddRef,
    session_rate_support_Release,
    session_rate_support_GetSlowestRate,
    session_rate_support_GetFastestRate,
    session_rate_support_IsRateSupported,
};

static HRESULT WINAPI session_rate_control_QueryInterface(IMFRateControl *iface, REFIID riid, void **obj)
{
    struct media_session *session = impl_session_from_IMFRateControl(iface);
    return IMFMediaSession_QueryInterface(&session->IMFMediaSession_iface, riid, obj);
}

static ULONG WINAPI session_rate_control_AddRef(IMFRateControl *iface)
{
    struct media_session *session = impl_session_from_IMFRateControl(iface);
    return IMFMediaSession_AddRef(&session->IMFMediaSession_iface);
}

static ULONG WINAPI session_rate_control_Release(IMFRateControl *iface)
{
    struct media_session *session = impl_session_from_IMFRateControl(iface);
    return IMFMediaSession_Release(&session->IMFMediaSession_iface);
}

static HRESULT WINAPI session_rate_control_SetRate(IMFRateControl *iface, BOOL thin, float rate)
{
    FIXME("%p, %d, %f.\n", iface, thin, rate);

    return E_NOTIMPL;
}

static HRESULT WINAPI session_rate_control_GetRate(IMFRateControl *iface, BOOL *thin, float *rate)
{
    struct media_session *session = impl_session_from_IMFRateControl(iface);

    TRACE("%p, %p, %p.\n", iface, thin, rate);

    return IMFRateControl_GetRate(session->clock_rate_control, thin, rate);
}

static const IMFRateControlVtbl session_rate_control_vtbl =
{
    session_rate_control_QueryInterface,
    session_rate_control_AddRef,
    session_rate_control_Release,
    session_rate_control_SetRate,
    session_rate_control_GetRate,
};

/***********************************************************************
 *      MFCreateMediaSession (mf.@)
 */
HRESULT WINAPI MFCreateMediaSession(IMFAttributes *config, IMFMediaSession **session)
{
    BOOL without_quality_manager = FALSE;
    struct media_session *object;
    HRESULT hr;

    TRACE("%p, %p.\n", config, session);

    object = heap_alloc_zero(sizeof(*object));
    if (!object)
        return E_OUTOFMEMORY;

    object->IMFMediaSession_iface.lpVtbl = &mfmediasessionvtbl;
    object->IMFGetService_iface.lpVtbl = &session_get_service_vtbl;
    object->IMFRateSupport_iface.lpVtbl = &session_rate_support_vtbl;
    object->IMFRateControl_iface.lpVtbl = &session_rate_control_vtbl;
    object->commands_callback.lpVtbl = &session_commands_callback_vtbl;
    object->events_callback.lpVtbl = &session_events_callback_vtbl;
    object->sink_finalizer_callback.lpVtbl = &session_sink_finalizer_callback_vtbl;
    object->refcount = 1;
    list_init(&object->topologies);
    list_init(&object->commands);
    list_init(&object->presentation.sources);
    list_init(&object->presentation.sinks);
    list_init(&object->presentation.nodes);
    InitializeCriticalSection(&object->cs);

    if (FAILED(hr = MFCreateTopology(&object->presentation.current_topology)))
        goto failed;

    if (FAILED(hr = MFCreateEventQueue(&object->event_queue)))
        goto failed;

    if (FAILED(hr = MFCreatePresentationClock(&object->clock)))
        goto failed;

    if (FAILED(hr = MFCreateSystemTimeSource(&object->system_time_source)))
        goto failed;

    if (FAILED(hr = IMFPresentationClock_QueryInterface(object->clock, &IID_IMFRateControl,
            (void **)&object->clock_rate_control)))
    {
        goto failed;
    }

    if (config)
    {
        GUID clsid;

        if (SUCCEEDED(IMFAttributes_GetGUID(config, &MF_SESSION_TOPOLOADER, &clsid)))
        {
            if (FAILED(hr = CoCreateInstance(&clsid, NULL, CLSCTX_INPROC_SERVER, &IID_IMFTopoLoader,
                    (void **)&object->topo_loader)))
            {
                WARN("Failed to create custom topology loader, hr %#x.\n", hr);
            }
        }

        if (SUCCEEDED(IMFAttributes_GetGUID(config, &MF_SESSION_QUALITY_MANAGER, &clsid)))
        {
            if (!(without_quality_manager = IsEqualGUID(&clsid, &GUID_NULL)))
            {
                if (FAILED(hr = CoCreateInstance(&clsid, NULL, CLSCTX_INPROC_SERVER, &IID_IMFQualityManager,
                        (void **)&object->quality_manager)))
                {
                    WARN("Failed to create custom quality manager, hr %#x.\n", hr);
                }
            }
        }
    }

    if (!object->topo_loader && FAILED(hr = MFCreateTopoLoader(&object->topo_loader)))
        goto failed;

    if (!object->quality_manager && !without_quality_manager &&
            FAILED(hr = MFCreateStandardQualityManager(&object->quality_manager)))
    {
        goto failed;
    }

    *session = &object->IMFMediaSession_iface;

    return S_OK;

failed:
    IMFMediaSession_Release(&object->IMFMediaSession_iface);
    return hr;
}

static HRESULT WINAPI sink_notification_QueryInterface(IUnknown *iface, REFIID riid, void **out)
{
    if (IsEqualIID(riid, &IID_IUnknown))
    {
        *out = iface;
        IUnknown_AddRef(iface);
        return S_OK;
    }

    WARN("Unsupported %s.\n", debugstr_guid(riid));
    *out = NULL;
    return E_NOINTERFACE;
}

static ULONG WINAPI sink_notification_AddRef(IUnknown *iface)
{
    struct sink_notification *notification = impl_sink_notification_from_IUnknown(iface);
    ULONG refcount = InterlockedIncrement(&notification->refcount);

    TRACE("%p, refcount %u.\n", iface, refcount);

    return refcount;
}

static ULONG WINAPI sink_notification_Release(IUnknown *iface)
{
    struct sink_notification *notification = impl_sink_notification_from_IUnknown(iface);
    ULONG refcount = InterlockedDecrement(&notification->refcount);

    TRACE("%p, refcount %u.\n", iface, refcount);

    if (!refcount)
    {
        IMFClockStateSink_Release(notification->sink);
        heap_free(notification);
    }

    return refcount;
}

static const IUnknownVtbl sinknotificationvtbl =
{
    sink_notification_QueryInterface,
    sink_notification_AddRef,
    sink_notification_Release,
};

static void clock_notify_async_sink(struct presentation_clock *clock, MFTIME system_time,
        struct clock_state_change_param param, enum clock_notification notification, IMFClockStateSink *sink)
{
    struct sink_notification *object;
    IMFAsyncResult *result;
    HRESULT hr;

    object = heap_alloc(sizeof(*object));
    if (!object)
        return;

    object->IUnknown_iface.lpVtbl = &sinknotificationvtbl;
    object->refcount = 1;
    object->system_time = system_time;
    object->param = param;
    object->notification = notification;
    object->sink = sink;
    IMFClockStateSink_AddRef(object->sink);

    hr = MFCreateAsyncResult(&object->IUnknown_iface, &clock->sink_callback, NULL, &result);
    IUnknown_Release(&object->IUnknown_iface);
    if (SUCCEEDED(hr))
    {
        MFPutWorkItemEx(MFASYNC_CALLBACK_QUEUE_STANDARD, result);
        IMFAsyncResult_Release(result);
    }
}

static HRESULT WINAPI present_clock_QueryInterface(IMFPresentationClock *iface, REFIID riid, void **out)
{
    struct presentation_clock *clock = impl_from_IMFPresentationClock(iface);

    TRACE("%p, %s, %p.\n", iface, debugstr_guid(riid), out);

    if (IsEqualIID(riid, &IID_IMFPresentationClock) ||
            IsEqualIID(riid, &IID_IMFClock) ||
            IsEqualIID(riid, &IID_IUnknown))
    {
        *out = &clock->IMFPresentationClock_iface;
    }
    else if (IsEqualIID(riid, &IID_IMFRateControl))
    {
        *out = &clock->IMFRateControl_iface;
    }
    else if (IsEqualIID(riid, &IID_IMFTimer))
    {
        *out = &clock->IMFTimer_iface;
    }
    else if (IsEqualIID(riid, &IID_IMFShutdown))
    {
        *out = &clock->IMFShutdown_iface;
    }
    else
    {
        WARN("Unsupported %s.\n", debugstr_guid(riid));
        *out = NULL;
        return E_NOINTERFACE;
    }

    IUnknown_AddRef((IUnknown *)*out);
    return S_OK;
}

static ULONG WINAPI present_clock_AddRef(IMFPresentationClock *iface)
{
    struct presentation_clock *clock = impl_from_IMFPresentationClock(iface);
    ULONG refcount = InterlockedIncrement(&clock->refcount);

    TRACE("%p, refcount %u.\n", iface, refcount);

    return refcount;
}

static ULONG WINAPI present_clock_Release(IMFPresentationClock *iface)
{
    struct presentation_clock *clock = impl_from_IMFPresentationClock(iface);
    ULONG refcount = InterlockedDecrement(&clock->refcount);
    struct clock_timer *timer, *timer2;
    struct clock_sink *sink, *sink2;

    TRACE("%p, refcount %u.\n", iface, refcount);

    if (!refcount)
    {
        if (clock->time_source)
            IMFPresentationTimeSource_Release(clock->time_source);
        if (clock->time_source_sink)
            IMFClockStateSink_Release(clock->time_source_sink);
        LIST_FOR_EACH_ENTRY_SAFE(sink, sink2, &clock->sinks, struct clock_sink, entry)
        {
            list_remove(&sink->entry);
            IMFClockStateSink_Release(sink->state_sink);
            heap_free(sink);
        }
        LIST_FOR_EACH_ENTRY_SAFE(timer, timer2, &clock->timers, struct clock_timer, entry)
        {
            list_remove(&timer->entry);
            IUnknown_Release(&timer->IUnknown_iface);
        }
        DeleteCriticalSection(&clock->cs);
        heap_free(clock);
    }

    return refcount;
}

static HRESULT WINAPI present_clock_GetClockCharacteristics(IMFPresentationClock *iface, DWORD *flags)
{
    struct presentation_clock *clock = impl_from_IMFPresentationClock(iface);
    HRESULT hr = MF_E_CLOCK_NO_TIME_SOURCE;

    TRACE("%p, %p.\n", iface, flags);

    EnterCriticalSection(&clock->cs);
    if (clock->time_source)
        hr = IMFPresentationTimeSource_GetClockCharacteristics(clock->time_source, flags);
    LeaveCriticalSection(&clock->cs);

    return hr;
}

static HRESULT WINAPI present_clock_GetCorrelatedTime(IMFPresentationClock *iface, DWORD reserved,
        LONGLONG *clock_time, MFTIME *system_time)
{
    struct presentation_clock *clock = impl_from_IMFPresentationClock(iface);
    HRESULT hr = MF_E_CLOCK_NO_TIME_SOURCE;

    TRACE("%p, %#x, %p, %p.\n", iface, reserved, clock_time, system_time);

    EnterCriticalSection(&clock->cs);
    if (clock->time_source)
        hr = IMFPresentationTimeSource_GetCorrelatedTime(clock->time_source, reserved, clock_time, system_time);
    LeaveCriticalSection(&clock->cs);

    return hr;
}

static HRESULT WINAPI present_clock_GetContinuityKey(IMFPresentationClock *iface, DWORD *key)
{
    TRACE("%p, %p.\n", iface, key);

    *key = 0;

    return S_OK;
}

static HRESULT WINAPI present_clock_GetState(IMFPresentationClock *iface, DWORD reserved, MFCLOCK_STATE *state)
{
    struct presentation_clock *clock = impl_from_IMFPresentationClock(iface);

    TRACE("%p, %#x, %p.\n", iface, reserved, state);

    EnterCriticalSection(&clock->cs);
    *state = clock->state;
    LeaveCriticalSection(&clock->cs);

    return S_OK;
}

static HRESULT WINAPI present_clock_GetProperties(IMFPresentationClock *iface, MFCLOCK_PROPERTIES *props)
{
    struct presentation_clock *clock = impl_from_IMFPresentationClock(iface);
    HRESULT hr = MF_E_CLOCK_NO_TIME_SOURCE;

    TRACE("%p, %p.\n", iface, props);

    EnterCriticalSection(&clock->cs);
    if (clock->time_source)
        hr = IMFPresentationTimeSource_GetProperties(clock->time_source, props);
    LeaveCriticalSection(&clock->cs);

    return hr;
}

static HRESULT WINAPI present_clock_SetTimeSource(IMFPresentationClock *iface,
        IMFPresentationTimeSource *time_source)
{
    struct presentation_clock *clock = impl_from_IMFPresentationClock(iface);
    MFCLOCK_PROPERTIES props;
    IMFClock *source_clock;
    HRESULT hr;

    TRACE("%p, %p.\n", iface, time_source);

    EnterCriticalSection(&clock->cs);

    if (clock->time_source)
        IMFPresentationTimeSource_Release(clock->time_source);
    if (clock->time_source_sink)
        IMFClockStateSink_Release(clock->time_source_sink);
    clock->time_source = NULL;
    clock->time_source_sink = NULL;

    hr = IMFPresentationTimeSource_QueryInterface(time_source, &IID_IMFClockStateSink, (void **)&clock->time_source_sink);
    if (SUCCEEDED(hr))
    {
        clock->time_source = time_source;
        IMFPresentationTimeSource_AddRef(clock->time_source);
    }

    if (SUCCEEDED(IMFPresentationTimeSource_GetUnderlyingClock(time_source, &source_clock)))
    {
        if (SUCCEEDED(IMFClock_GetProperties(source_clock, &props)))
            clock->frequency = props.qwClockFrequency;
        IMFClock_Release(source_clock);
    }

    if (!clock->frequency)
        clock->frequency = MFCLOCK_FREQUENCY_HNS;

    LeaveCriticalSection(&clock->cs);

    return hr;
}

static HRESULT WINAPI present_clock_GetTimeSource(IMFPresentationClock *iface,
        IMFPresentationTimeSource **time_source)
{
    struct presentation_clock *clock = impl_from_IMFPresentationClock(iface);
    HRESULT hr = S_OK;

    TRACE("%p, %p.\n", iface, time_source);

    if (!time_source)
        return E_INVALIDARG;

    EnterCriticalSection(&clock->cs);
    if (clock->time_source)
    {
        *time_source = clock->time_source;
        IMFPresentationTimeSource_AddRef(*time_source);
    }
    else
        hr = MF_E_CLOCK_NO_TIME_SOURCE;
    LeaveCriticalSection(&clock->cs);

    return hr;
}

static HRESULT WINAPI present_clock_GetTime(IMFPresentationClock *iface, MFTIME *time)
{
    struct presentation_clock *clock = impl_from_IMFPresentationClock(iface);
    HRESULT hr = MF_E_CLOCK_NO_TIME_SOURCE;
    MFTIME systime;

    TRACE("%p, %p.\n", iface, time);

    if (!time)
        return E_POINTER;

    EnterCriticalSection(&clock->cs);
    if (clock->time_source)
        hr = IMFPresentationTimeSource_GetCorrelatedTime(clock->time_source, 0, time, &systime);
    LeaveCriticalSection(&clock->cs);

    return hr;
}

static HRESULT WINAPI present_clock_AddClockStateSink(IMFPresentationClock *iface, IMFClockStateSink *state_sink)
{
    struct presentation_clock *clock = impl_from_IMFPresentationClock(iface);
    struct clock_sink *sink, *cur;
    HRESULT hr = S_OK;

    TRACE("%p, %p.\n", iface, state_sink);

    if (!state_sink)
        return E_INVALIDARG;

    sink = heap_alloc(sizeof(*sink));
    if (!sink)
        return E_OUTOFMEMORY;

    sink->state_sink = state_sink;
    IMFClockStateSink_AddRef(sink->state_sink);

    EnterCriticalSection(&clock->cs);
    LIST_FOR_EACH_ENTRY(cur, &clock->sinks, struct clock_sink, entry)
    {
        if (cur->state_sink == state_sink)
        {
            hr = E_INVALIDARG;
            break;
        }
    }
    if (SUCCEEDED(hr))
    {
        static const enum clock_notification notifications[MFCLOCK_STATE_PAUSED + 1] =
        {
            /* MFCLOCK_STATE_INVALID */ 0, /* Does not apply */
            /* MFCLOCK_STATE_RUNNING */ CLOCK_NOTIFY_START,
            /* MFCLOCK_STATE_STOPPED */ CLOCK_NOTIFY_STOP,
            /* MFCLOCK_STATE_PAUSED  */ CLOCK_NOTIFY_PAUSE,
        };
        struct clock_state_change_param param;

        if (!clock->is_shut_down && clock->state != MFCLOCK_STATE_INVALID)
        {
            param.u.offset = clock->start_offset;
            clock_notify_async_sink(clock, MFGetSystemTime(), param, notifications[clock->state], sink->state_sink);
        }

        list_add_tail(&clock->sinks, &sink->entry);
    }
    LeaveCriticalSection(&clock->cs);

    if (FAILED(hr))
    {
        IMFClockStateSink_Release(sink->state_sink);
        heap_free(sink);
    }

    return hr;
}

static HRESULT WINAPI present_clock_RemoveClockStateSink(IMFPresentationClock *iface,
        IMFClockStateSink *state_sink)
{
    struct presentation_clock *clock = impl_from_IMFPresentationClock(iface);
    struct clock_sink *sink;

    TRACE("%p, %p.\n", iface, state_sink);

    if (!state_sink)
        return E_INVALIDARG;

    EnterCriticalSection(&clock->cs);
    LIST_FOR_EACH_ENTRY(sink, &clock->sinks, struct clock_sink, entry)
    {
        if (sink->state_sink == state_sink)
        {
            IMFClockStateSink_Release(sink->state_sink);
            list_remove(&sink->entry);
            heap_free(sink);
            break;
        }
    }
    LeaveCriticalSection(&clock->cs);

    return S_OK;
}

static HRESULT clock_call_state_change(MFTIME system_time, struct clock_state_change_param param,
        enum clock_notification notification, IMFClockStateSink *sink)
{
    HRESULT hr = S_OK;

    switch (notification)
    {
        case CLOCK_NOTIFY_START:
            hr = IMFClockStateSink_OnClockStart(sink, system_time, param.u.offset);
            break;
        case CLOCK_NOTIFY_STOP:
            hr = IMFClockStateSink_OnClockStop(sink, system_time);
            break;
        case CLOCK_NOTIFY_PAUSE:
            hr = IMFClockStateSink_OnClockPause(sink, system_time);
            break;
        case CLOCK_NOTIFY_RESTART:
            hr = IMFClockStateSink_OnClockRestart(sink, system_time);
            break;
        case CLOCK_NOTIFY_SET_RATE:
            /* System time source does not allow 0.0 rate, presentation clock allows it without raising errors. */
            IMFClockStateSink_OnClockSetRate(sink, system_time, param.u.rate);
            break;
        default:
            ;
    }

    return hr;
}

static HRESULT clock_change_state(struct presentation_clock *clock, enum clock_command command,
        struct clock_state_change_param param)
{
    static const BYTE state_change_is_allowed[MFCLOCK_STATE_PAUSED+1][CLOCK_CMD_MAX] =
    {   /*              S  S* P, R  */
        /* INVALID */ { 1, 1, 1, 1 },
        /* RUNNING */ { 1, 1, 1, 1 },
        /* STOPPED */ { 1, 1, 0, 1 },
        /* PAUSED  */ { 1, 1, 0, 1 },
    };
    static const MFCLOCK_STATE states[CLOCK_CMD_MAX] =
    {
        /* CLOCK_CMD_START    */ MFCLOCK_STATE_RUNNING,
        /* CLOCK_CMD_STOP     */ MFCLOCK_STATE_STOPPED,
        /* CLOCK_CMD_PAUSE    */ MFCLOCK_STATE_PAUSED,
        /* CLOCK_CMD_SET_RATE */ 0, /* Unused */
    };
    static const enum clock_notification notifications[CLOCK_CMD_MAX] =
    {
        /* CLOCK_CMD_START    */ CLOCK_NOTIFY_START,
        /* CLOCK_CMD_STOP     */ CLOCK_NOTIFY_STOP,
        /* CLOCK_CMD_PAUSE    */ CLOCK_NOTIFY_PAUSE,
        /* CLOCK_CMD_SET_RATE */ CLOCK_NOTIFY_SET_RATE,
    };
    enum clock_notification notification;
    struct clock_sink *sink;
    MFCLOCK_STATE old_state;
    IMFAsyncResult *result;
    MFTIME system_time;
    HRESULT hr;

    if (!clock->time_source)
        return MF_E_CLOCK_NO_TIME_SOURCE;

    if (command != CLOCK_CMD_SET_RATE && clock->state == states[command] && clock->state != MFCLOCK_STATE_RUNNING)
        return MF_E_CLOCK_STATE_ALREADY_SET;

    if (!state_change_is_allowed[clock->state][command])
        return MF_E_INVALIDREQUEST;

    system_time = MFGetSystemTime();

    if (command == CLOCK_CMD_START && clock->state == MFCLOCK_STATE_PAUSED &&
            param.u.offset == PRESENTATION_CURRENT_POSITION)
    {
        notification = CLOCK_NOTIFY_RESTART;
    }
    else
        notification = notifications[command];

    if (FAILED(hr = clock_call_state_change(system_time, param, notification, clock->time_source_sink)))
        return hr;

    old_state = clock->state;
    if (command != CLOCK_CMD_SET_RATE)
        clock->state = states[command];

    /* Dump all pending timer requests immediately on start; otherwise try to cancel scheduled items when
       transitioning from running state. */
    if ((clock->state == MFCLOCK_STATE_RUNNING) ^ (old_state == MFCLOCK_STATE_RUNNING))
    {
        struct clock_timer *timer, *timer2;

        if (clock->state == MFCLOCK_STATE_RUNNING)
        {
            LIST_FOR_EACH_ENTRY_SAFE(timer, timer2, &clock->timers, struct clock_timer, entry)
            {
                list_remove(&timer->entry);
                hr = MFCreateAsyncResult(&timer->IUnknown_iface, &clock->timer_callback, NULL, &result);
                IUnknown_Release(&timer->IUnknown_iface);
                if (SUCCEEDED(hr))
                {
                    MFPutWorkItemEx(MFASYNC_CALLBACK_QUEUE_TIMER, result);
                    IMFAsyncResult_Release(result);
                }
            }
        }
        else
        {
            LIST_FOR_EACH_ENTRY(timer, &clock->timers, struct clock_timer, entry)
            {
                if (timer->key)
                {
                    MFCancelWorkItem(timer->key);
                    timer->key = 0;
                }
            }
        }
    }

    LIST_FOR_EACH_ENTRY(sink, &clock->sinks, struct clock_sink, entry)
    {
        clock_notify_async_sink(clock, system_time, param, notification, sink->state_sink);
    }

    return S_OK;
}

static HRESULT WINAPI present_clock_Start(IMFPresentationClock *iface, LONGLONG start_offset)
{
    struct presentation_clock *clock = impl_from_IMFPresentationClock(iface);
    struct clock_state_change_param param = {{0}};
    HRESULT hr;

    TRACE("%p, %s.\n", iface, debugstr_time(start_offset));

    EnterCriticalSection(&clock->cs);
    clock->start_offset = param.u.offset = start_offset;
    hr = clock_change_state(clock, CLOCK_CMD_START, param);
    LeaveCriticalSection(&clock->cs);

    return hr;
}

static HRESULT WINAPI present_clock_Stop(IMFPresentationClock *iface)
{
    struct presentation_clock *clock = impl_from_IMFPresentationClock(iface);
    struct clock_state_change_param param = {{0}};
    HRESULT hr;

    TRACE("%p.\n", iface);

    EnterCriticalSection(&clock->cs);
    hr = clock_change_state(clock, CLOCK_CMD_STOP, param);
    LeaveCriticalSection(&clock->cs);

    return hr;
}

static HRESULT WINAPI present_clock_Pause(IMFPresentationClock *iface)
{
    struct presentation_clock *clock = impl_from_IMFPresentationClock(iface);
    struct clock_state_change_param param = {{0}};
    HRESULT hr;

    TRACE("%p.\n", iface);

    EnterCriticalSection(&clock->cs);
    hr = clock_change_state(clock, CLOCK_CMD_PAUSE, param);
    LeaveCriticalSection(&clock->cs);

    return hr;
}

static const IMFPresentationClockVtbl presentationclockvtbl =
{
    present_clock_QueryInterface,
    present_clock_AddRef,
    present_clock_Release,
    present_clock_GetClockCharacteristics,
    present_clock_GetCorrelatedTime,
    present_clock_GetContinuityKey,
    present_clock_GetState,
    present_clock_GetProperties,
    present_clock_SetTimeSource,
    present_clock_GetTimeSource,
    present_clock_GetTime,
    present_clock_AddClockStateSink,
    present_clock_RemoveClockStateSink,
    present_clock_Start,
    present_clock_Stop,
    present_clock_Pause,
};

static HRESULT WINAPI present_clock_rate_control_QueryInterface(IMFRateControl *iface, REFIID riid, void **out)
{
    struct presentation_clock *clock = impl_from_IMFRateControl(iface);
    return IMFPresentationClock_QueryInterface(&clock->IMFPresentationClock_iface, riid, out);
}

static ULONG WINAPI present_clock_rate_control_AddRef(IMFRateControl *iface)
{
    struct presentation_clock *clock = impl_from_IMFRateControl(iface);
    return IMFPresentationClock_AddRef(&clock->IMFPresentationClock_iface);
}

static ULONG WINAPI present_clock_rate_control_Release(IMFRateControl *iface)
{
    struct presentation_clock *clock = impl_from_IMFRateControl(iface);
    return IMFPresentationClock_Release(&clock->IMFPresentationClock_iface);
}

static HRESULT WINAPI present_clock_rate_SetRate(IMFRateControl *iface, BOOL thin, float rate)
{
    struct presentation_clock *clock = impl_from_IMFRateControl(iface);
    struct clock_state_change_param param;
    HRESULT hr;

    TRACE("%p, %d, %f.\n", iface, thin, rate);

    if (thin)
        return MF_E_THINNING_UNSUPPORTED;

    EnterCriticalSection(&clock->cs);
    param.u.rate = rate;
    if (SUCCEEDED(hr = clock_change_state(clock, CLOCK_CMD_SET_RATE, param)))
        clock->rate = rate;
    LeaveCriticalSection(&clock->cs);

    return hr;
}

static HRESULT WINAPI present_clock_rate_GetRate(IMFRateControl *iface, BOOL *thin, float *rate)
{
    struct presentation_clock *clock = impl_from_IMFRateControl(iface);

    TRACE("%p, %p, %p.\n", iface, thin, rate);

    if (!rate)
        return E_INVALIDARG;

    if (thin)
        *thin = FALSE;

    EnterCriticalSection(&clock->cs);
    *rate = clock->rate;
    LeaveCriticalSection(&clock->cs);

    return S_OK;
}

static const IMFRateControlVtbl presentclockratecontrolvtbl =
{
    present_clock_rate_control_QueryInterface,
    present_clock_rate_control_AddRef,
    present_clock_rate_control_Release,
    present_clock_rate_SetRate,
    present_clock_rate_GetRate,
};

static HRESULT WINAPI present_clock_timer_QueryInterface(IMFTimer *iface, REFIID riid, void **out)
{
    struct presentation_clock *clock = impl_from_IMFTimer(iface);
    return IMFPresentationClock_QueryInterface(&clock->IMFPresentationClock_iface, riid, out);
}

static ULONG WINAPI present_clock_timer_AddRef(IMFTimer *iface)
{
    struct presentation_clock *clock = impl_from_IMFTimer(iface);
    return IMFPresentationClock_AddRef(&clock->IMFPresentationClock_iface);
}

static ULONG WINAPI present_clock_timer_Release(IMFTimer *iface)
{
    struct presentation_clock *clock = impl_from_IMFTimer(iface);
    return IMFPresentationClock_Release(&clock->IMFPresentationClock_iface);
}

static HRESULT present_clock_schedule_timer(struct presentation_clock *clock, DWORD flags, LONGLONG time,
        struct clock_timer *timer)
{
    IMFAsyncResult *result;
    MFTIME systime, clocktime;
    LONGLONG frequency;
    HRESULT hr;

    if (!(flags & MFTIMER_RELATIVE))
    {
        if (FAILED(hr = IMFPresentationTimeSource_GetCorrelatedTime(clock->time_source, 0, &clocktime, &systime)))
        {
            WARN("Failed to get clock time, hr %#x.\n", hr);
            return hr;
        }
        time -= clocktime;
    }

    frequency = clock->frequency / 1000;
    time /= frequency;

    /* Scheduled item is using clock instance callback, with timer instance as an object. Clock callback will
       call user callback and cleanup timer list. */

    if (FAILED(hr = MFCreateAsyncResult(&timer->IUnknown_iface, &clock->timer_callback, NULL, &result)))
        return hr;

    hr = MFScheduleWorkItemEx(result, -time, &timer->key);
    IMFAsyncResult_Release(result);

    return hr;
}

static HRESULT WINAPI clock_timer_QueryInterface(IUnknown *iface, REFIID riid, void **obj)
{
    if (IsEqualIID(riid, &IID_IUnknown))
    {
        *obj = iface;
        IUnknown_AddRef(iface);
        return S_OK;
    }

    *obj = NULL;
    return E_NOINTERFACE;
}

static ULONG WINAPI clock_timer_AddRef(IUnknown *iface)
{
    struct clock_timer *timer = impl_clock_timer_from_IUnknown(iface);
    return InterlockedIncrement(&timer->refcount);
}

static ULONG WINAPI clock_timer_Release(IUnknown *iface)
{
    struct clock_timer *timer = impl_clock_timer_from_IUnknown(iface);
    ULONG refcount = InterlockedDecrement(&timer->refcount);

    if (!refcount)
    {
        IMFAsyncResult_Release(timer->result);
        IMFAsyncCallback_Release(timer->callback);
        heap_free(timer);
    }

    return refcount;
}

static const IUnknownVtbl clock_timer_vtbl =
{
    clock_timer_QueryInterface,
    clock_timer_AddRef,
    clock_timer_Release,
};

static HRESULT WINAPI present_clock_timer_SetTimer(IMFTimer *iface, DWORD flags, LONGLONG time,
        IMFAsyncCallback *callback, IUnknown *state, IUnknown **cancel_key)
{
    struct presentation_clock *clock = impl_from_IMFTimer(iface);
    struct clock_timer *clock_timer;
    HRESULT hr;

    TRACE("%p, %#x, %s, %p, %p, %p.\n", iface, flags, debugstr_time(time), callback, state, cancel_key);

    if (!(clock_timer = heap_alloc_zero(sizeof(*clock_timer))))
        return E_OUTOFMEMORY;

    if (FAILED(hr = MFCreateAsyncResult(NULL, NULL, state, &clock_timer->result)))
    {
        heap_free(clock_timer);
        return hr;
    }

    clock_timer->IUnknown_iface.lpVtbl = &clock_timer_vtbl;
    clock_timer->refcount = 1;
    clock_timer->callback = callback;
    IMFAsyncCallback_AddRef(clock_timer->callback);

    EnterCriticalSection(&clock->cs);

    if (clock->state == MFCLOCK_STATE_RUNNING)
        hr = present_clock_schedule_timer(clock, flags, time, clock_timer);
    else if (clock->state == MFCLOCK_STATE_STOPPED)
        hr = MF_S_CLOCK_STOPPED;

    if (SUCCEEDED(hr))
    {
        list_add_tail(&clock->timers, &clock_timer->entry);
        if (cancel_key)
        {
            *cancel_key = &clock_timer->IUnknown_iface;
            IUnknown_AddRef(*cancel_key);
        }
    }

    LeaveCriticalSection(&clock->cs);

    if (FAILED(hr))
        IUnknown_Release(&clock_timer->IUnknown_iface);

    return hr;
}

static HRESULT WINAPI present_clock_timer_CancelTimer(IMFTimer *iface, IUnknown *cancel_key)
{
    struct presentation_clock *clock = impl_from_IMFTimer(iface);
    struct clock_timer *timer;

    TRACE("%p, %p.\n", iface, cancel_key);

    EnterCriticalSection(&clock->cs);

    LIST_FOR_EACH_ENTRY(timer, &clock->timers, struct clock_timer, entry)
    {
        if (&timer->IUnknown_iface == cancel_key)
        {
            list_remove(&timer->entry);
            if (timer->key)
            {
                MFCancelWorkItem(timer->key);
                timer->key = 0;
            }
            IUnknown_Release(&timer->IUnknown_iface);
            break;
        }
    }

    LeaveCriticalSection(&clock->cs);

    return S_OK;
}

static const IMFTimerVtbl presentclocktimervtbl =
{
    present_clock_timer_QueryInterface,
    present_clock_timer_AddRef,
    present_clock_timer_Release,
    present_clock_timer_SetTimer,
    present_clock_timer_CancelTimer,
};

static HRESULT WINAPI present_clock_shutdown_QueryInterface(IMFShutdown *iface, REFIID riid, void **out)
{
    struct presentation_clock *clock = impl_from_IMFShutdown(iface);
    return IMFPresentationClock_QueryInterface(&clock->IMFPresentationClock_iface, riid, out);
}

static ULONG WINAPI present_clock_shutdown_AddRef(IMFShutdown *iface)
{
    struct presentation_clock *clock = impl_from_IMFShutdown(iface);
    return IMFPresentationClock_AddRef(&clock->IMFPresentationClock_iface);
}

static ULONG WINAPI present_clock_shutdown_Release(IMFShutdown *iface)
{
    struct presentation_clock *clock = impl_from_IMFShutdown(iface);
    return IMFPresentationClock_Release(&clock->IMFPresentationClock_iface);
}

static HRESULT WINAPI present_clock_shutdown_Shutdown(IMFShutdown *iface)
{
    struct presentation_clock *clock = impl_from_IMFShutdown(iface);

    TRACE("%p.\n", iface);

    EnterCriticalSection(&clock->cs);
    clock->is_shut_down = TRUE;
    LeaveCriticalSection(&clock->cs);

    return S_OK;
}

static HRESULT WINAPI present_clock_shutdown_GetShutdownStatus(IMFShutdown *iface, MFSHUTDOWN_STATUS *status)
{
    struct presentation_clock *clock = impl_from_IMFShutdown(iface);
    HRESULT hr = S_OK;

    TRACE("%p, %p.\n", iface, status);

    if (!status)
        return E_INVALIDARG;

    EnterCriticalSection(&clock->cs);
    if (clock->is_shut_down)
        *status = MFSHUTDOWN_COMPLETED;
    else
        hr = MF_E_INVALIDREQUEST;
    LeaveCriticalSection(&clock->cs);

    return hr;
}

static const IMFShutdownVtbl presentclockshutdownvtbl =
{
    present_clock_shutdown_QueryInterface,
    present_clock_shutdown_AddRef,
    present_clock_shutdown_Release,
    present_clock_shutdown_Shutdown,
    present_clock_shutdown_GetShutdownStatus,
};

static HRESULT WINAPI present_clock_callback_QueryInterface(IMFAsyncCallback *iface, REFIID riid, void **out)
{
    if (IsEqualIID(riid, &IID_IMFAsyncCallback) ||
            IsEqualIID(riid, &IID_IUnknown))
    {
        *out = iface;
        IMFAsyncCallback_AddRef(iface);
        return S_OK;
    }

    WARN("Unsupported %s.\n", wine_dbgstr_guid(riid));
    *out = NULL;
    return E_NOINTERFACE;
}

static ULONG WINAPI present_clock_sink_callback_AddRef(IMFAsyncCallback *iface)
{
    struct presentation_clock *clock = impl_from_sink_callback_IMFAsyncCallback(iface);
    return IMFPresentationClock_AddRef(&clock->IMFPresentationClock_iface);
}

static ULONG WINAPI present_clock_sink_callback_Release(IMFAsyncCallback *iface)
{
    struct presentation_clock *clock = impl_from_sink_callback_IMFAsyncCallback(iface);
    return IMFPresentationClock_Release(&clock->IMFPresentationClock_iface);
}

static HRESULT WINAPI present_clock_callback_GetParameters(IMFAsyncCallback *iface, DWORD *flags, DWORD *queue)
{
    return E_NOTIMPL;
}

static HRESULT WINAPI present_clock_sink_callback_Invoke(IMFAsyncCallback *iface, IMFAsyncResult *result)
{
    struct sink_notification *data;
    IUnknown *object;
    HRESULT hr;

    if (FAILED(hr = IMFAsyncResult_GetObject(result, &object)))
        return hr;

    data = impl_sink_notification_from_IUnknown(object);

    clock_call_state_change(data->system_time, data->param, data->notification, data->sink);

    IUnknown_Release(object);

    return S_OK;
}

static const IMFAsyncCallbackVtbl presentclocksinkcallbackvtbl =
{
    present_clock_callback_QueryInterface,
    present_clock_sink_callback_AddRef,
    present_clock_sink_callback_Release,
    present_clock_callback_GetParameters,
    present_clock_sink_callback_Invoke,
};

static ULONG WINAPI present_clock_timer_callback_AddRef(IMFAsyncCallback *iface)
{
    struct presentation_clock *clock = impl_from_timer_callback_IMFAsyncCallback(iface);
    return IMFPresentationClock_AddRef(&clock->IMFPresentationClock_iface);
}

static ULONG WINAPI present_clock_timer_callback_Release(IMFAsyncCallback *iface)
{
    struct presentation_clock *clock = impl_from_timer_callback_IMFAsyncCallback(iface);
    return IMFPresentationClock_Release(&clock->IMFPresentationClock_iface);
}

static HRESULT WINAPI present_clock_timer_callback_Invoke(IMFAsyncCallback *iface, IMFAsyncResult *result)
{
    struct presentation_clock *clock = impl_from_timer_callback_IMFAsyncCallback(iface);
    struct clock_timer *timer;
    IUnknown *object;
    HRESULT hr;

    if (FAILED(hr = IMFAsyncResult_GetObject(result, &object)))
        return hr;

    timer = impl_clock_timer_from_IUnknown(object);

    EnterCriticalSection(&clock->cs);
    list_remove(&timer->entry);
    IUnknown_Release(&timer->IUnknown_iface);
    LeaveCriticalSection(&clock->cs);

    IMFAsyncCallback_Invoke(timer->callback, timer->result);

    IUnknown_Release(object);

    return S_OK;
}

static const IMFAsyncCallbackVtbl presentclocktimercallbackvtbl =
{
    present_clock_callback_QueryInterface,
    present_clock_timer_callback_AddRef,
    present_clock_timer_callback_Release,
    present_clock_callback_GetParameters,
    present_clock_timer_callback_Invoke,
};

/***********************************************************************
 *      MFCreatePresentationClock (mf.@)
 */
HRESULT WINAPI MFCreatePresentationClock(IMFPresentationClock **clock)
{
    struct presentation_clock *object;

    TRACE("%p.\n", clock);

    object = heap_alloc_zero(sizeof(*object));
    if (!object)
        return E_OUTOFMEMORY;

    object->IMFPresentationClock_iface.lpVtbl = &presentationclockvtbl;
    object->IMFRateControl_iface.lpVtbl = &presentclockratecontrolvtbl;
    object->IMFTimer_iface.lpVtbl = &presentclocktimervtbl;
    object->IMFShutdown_iface.lpVtbl = &presentclockshutdownvtbl;
    object->sink_callback.lpVtbl = &presentclocksinkcallbackvtbl;
    object->timer_callback.lpVtbl = &presentclocktimercallbackvtbl;
    object->refcount = 1;
    list_init(&object->sinks);
    list_init(&object->timers);
    object->rate = 1.0f;
    InitializeCriticalSection(&object->cs);

    *clock = &object->IMFPresentationClock_iface;

    return S_OK;
}

static HRESULT WINAPI standard_quality_manager_QueryInterface(IMFQualityManager *iface, REFIID riid, void **out)
{
    TRACE("%p, %s, %p.\n", iface, debugstr_guid(riid), out);

    if (IsEqualIID(riid, &IID_IMFQualityManager) ||
            IsEqualIID(riid, &IID_IUnknown))
    {
        *out = iface;
        IMFQualityManager_AddRef(iface);
        return S_OK;
    }

    WARN("Unsupported %s.\n", debugstr_guid(riid));
    *out = NULL;
    return E_NOINTERFACE;
}

static ULONG WINAPI standard_quality_manager_AddRef(IMFQualityManager *iface)
{
    struct quality_manager *manager = impl_from_IMFQualityManager(iface);
    ULONG refcount = InterlockedIncrement(&manager->refcount);

    TRACE("%p, refcount %u.\n", iface, refcount);

    return refcount;
}

static ULONG WINAPI standard_quality_manager_Release(IMFQualityManager *iface)
{
    struct quality_manager *manager = impl_from_IMFQualityManager(iface);
    ULONG refcount = InterlockedDecrement(&manager->refcount);

    TRACE("%p, refcount %u.\n", iface, refcount);

    if (!refcount)
    {
        heap_free(manager);
    }

    return refcount;
}

static HRESULT WINAPI standard_quality_manager_NotifyTopology(IMFQualityManager *iface, IMFTopology *topology)
{
    FIXME("%p, %p stub.\n", iface, topology);

    return E_NOTIMPL;
}

static HRESULT WINAPI standard_quality_manager_NotifyPresentationClock(IMFQualityManager *iface,
        IMFPresentationClock *clock)
{
    FIXME("%p, %p stub.\n", iface, clock);

    return E_NOTIMPL;
}

static HRESULT WINAPI standard_quality_manager_NotifyProcessInput(IMFQualityManager *iface, IMFTopologyNode *node,
        LONG input_index, IMFSample *sample)
{
    FIXME("%p, %p, %d, %p stub.\n", iface, node, input_index, sample);

    return E_NOTIMPL;
}

static HRESULT WINAPI standard_quality_manager_NotifyProcessOutput(IMFQualityManager *iface, IMFTopologyNode *node,
        LONG output_index, IMFSample *sample)
{
    FIXME("%p, %p, %d, %p stub.\n", iface, node, output_index, sample);

    return E_NOTIMPL;
}

static HRESULT WINAPI standard_quality_manager_NotifyQualityEvent(IMFQualityManager *iface, IUnknown *object,
        IMFMediaEvent *event)
{
    FIXME("%p, %p, %p stub.\n", iface, object, event);

    return E_NOTIMPL;
}

static HRESULT WINAPI standard_quality_manager_Shutdown(IMFQualityManager *iface)
{
    FIXME("%p stub.\n", iface);

    return E_NOTIMPL;
}

static IMFQualityManagerVtbl standard_quality_manager_vtbl =
{
    standard_quality_manager_QueryInterface,
    standard_quality_manager_AddRef,
    standard_quality_manager_Release,
    standard_quality_manager_NotifyTopology,
    standard_quality_manager_NotifyPresentationClock,
    standard_quality_manager_NotifyProcessInput,
    standard_quality_manager_NotifyProcessOutput,
    standard_quality_manager_NotifyQualityEvent,
    standard_quality_manager_Shutdown,
};

HRESULT WINAPI MFCreateStandardQualityManager(IMFQualityManager **manager)
{
    struct quality_manager *object;

    TRACE("%p.\n", manager);

    object = heap_alloc_zero(sizeof(*object));
    if (!object)
        return E_OUTOFMEMORY;

    object->IMFQualityManager_iface.lpVtbl = &standard_quality_manager_vtbl;
    object->refcount = 1;

    *manager = &object->IMFQualityManager_iface;

    return S_OK;
}