/*
 * Copyright 2016 Paul Gofman
 *
 * 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 "config.h"
#include "wine/port.h"

#include "d3dx9_private.h"

#include <float.h>

WINE_DEFAULT_DEBUG_CHANNEL(d3dx);

enum pres_ops
{
    PRESHADER_OP_NOP,
    PRESHADER_OP_MOV,
};

typedef double (*pres_op_func)(double *args, int ncomp);

static double pres_mov(double *args, int ncomp) {return args[0];}

#define PRES_OPCODE_MASK 0x7ff00000
#define PRES_OPCODE_SHIFT 20
#define PRES_SCALAR_FLAG 0x80000000
#define PRES_NCOMP_MASK  0x0000ffff

#define FOURCC_PRES 0x53455250
#define FOURCC_CLIT 0x54494c43
#define FOURCC_FXLC 0x434c5846
#define FOURCC_PRSI 0x49535250
#define PRES_SIGN 0x46580000

struct op_info
{
    unsigned int opcode;
    char mnem[8];
    unsigned int input_count;
    BOOL func_all_comps;
    pres_op_func func;
};

static const struct op_info pres_op_info[] =
{
    {0x000, "nop", 0, 0, NULL    }, /* PRESHADER_OP_NOP */
    {0x100, "mov", 1, 0, pres_mov}, /* PRESHADER_OP_MOV */
};

enum pres_value_type
{
    PRES_VT_FLOAT,
    PRES_VT_DOUBLE,
    PRES_VT_INT,
    PRES_VT_BOOL
};

static const struct
{
    unsigned int component_size;
    unsigned int reg_component_count;
    enum pres_value_type type;
}
table_info[] =
{
    {sizeof(double), 1, PRES_VT_DOUBLE}, /* PRES_REGTAB_IMMED */
    {sizeof(float),  4, PRES_VT_FLOAT }, /* PRES_REGTAB_CONST */
    {sizeof(float),  4, PRES_VT_FLOAT }, /* PRES_REGTAB_OCONST */
    {sizeof(BOOL),   1, PRES_VT_BOOL  }, /* PRES_REGTAB_OBCONST */
    {sizeof(int),    4, PRES_VT_INT,  }, /* PRES_REGTAB_OICONST */
    /* TODO: use double precision for 64 bit */
    {sizeof(float),  4, PRES_VT_FLOAT }  /* PRES_REGTAB_TEMP */
};

static const enum pres_reg_tables pres_regset2table[] =
{
    PRES_REGTAB_OBCONST,  /* D3DXRS_BOOL */
    PRES_REGTAB_OICONST,  /* D3DXRS_INT4 */
    PRES_REGTAB_CONST,    /* D3DXRS_FLOAT4 */
    PRES_REGTAB_COUNT,     /* D3DXRS_SAMPLER */
};

static const enum pres_reg_tables shad_regset2table[] =
{
    PRES_REGTAB_OBCONST,  /* D3DXRS_BOOL */
    PRES_REGTAB_OICONST,  /* D3DXRS_INT4 */
    PRES_REGTAB_OCONST,   /* D3DXRS_FLOAT4 */
    PRES_REGTAB_COUNT,     /* D3DXRS_SAMPLER */
};

struct d3dx_pres_operand
{
    enum pres_reg_tables table;
    /* offset is component index, not register index, e. g.
       offset for component c3.y is 13 (3 * 4 + 1) */
    unsigned int offset;
};

#define MAX_INPUTS_COUNT 3

struct d3dx_pres_ins
{
    enum pres_ops op;
    /* first input argument is scalar,
       scalar component is propagated */
    BOOL scalar_op;
    unsigned int component_count;
    struct d3dx_pres_operand inputs[MAX_INPUTS_COUNT];
    struct d3dx_pres_operand output;
};

static unsigned int get_reg_offset(unsigned int table, unsigned int offset)
{
    return offset / table_info[table].reg_component_count;
}

#define PRES_BITMASK_BLOCK_SIZE (sizeof(unsigned int) * 8)

static HRESULT regstore_alloc_table(struct d3dx_regstore *rs, unsigned int table)
{
    unsigned int size;

    size = rs->table_sizes[table] * table_info[table].reg_component_count * table_info[table].component_size;
    if (size)
    {
        rs->tables[table] = HeapAlloc(GetProcessHeap(), HEAP_ZERO_MEMORY, size);
        rs->table_value_set[table] = HeapAlloc(GetProcessHeap(), HEAP_ZERO_MEMORY,
                sizeof(*rs->table_value_set[table]) *
                ((rs->table_sizes[table] + PRES_BITMASK_BLOCK_SIZE - 1) / PRES_BITMASK_BLOCK_SIZE));
        if (!rs->tables[table] || !rs->table_value_set[table])
            return E_OUTOFMEMORY;
    }
    return D3D_OK;
}

static void regstore_free_tables(struct d3dx_regstore *rs)
{
    unsigned int i;

    for (i = 0; i < PRES_REGTAB_COUNT; ++i)
    {
        HeapFree(GetProcessHeap(), 0, rs->tables[i]);
        HeapFree(GetProcessHeap(), 0, rs->table_value_set[i]);
    }
}

static void regstore_set_values(struct d3dx_regstore *rs, unsigned int table, void *data,
        unsigned int start_offset, unsigned int count)
{
    unsigned int block_idx, start, end, start_block, end_block;

    if (!count)
        return;

    memcpy((BYTE *)rs->tables[table] + start_offset * table_info[table].component_size,
            data, count * table_info[table].component_size);

    start = get_reg_offset(table, start_offset);
    start_block = start / PRES_BITMASK_BLOCK_SIZE;
    start -= start_block * PRES_BITMASK_BLOCK_SIZE;
    end = get_reg_offset(table, start_offset + count - 1);
    end_block = end / PRES_BITMASK_BLOCK_SIZE;
    end = (end_block + 1) * PRES_BITMASK_BLOCK_SIZE - 1 - end;

    if (start_block == end_block)
    {
        rs->table_value_set[table][start_block] |= (~0u << start) & (~0u >> end);
    }
    else
    {
        rs->table_value_set[table][start_block] |= ~0u << start;

        for (block_idx = start_block + 1; block_idx < end_block; ++block_idx)
            rs->table_value_set[table][block_idx] = ~0u;

        rs->table_value_set[table][end_block] |= ~0u >> end;
    }
}

static void dump_bytecode(void *data, unsigned int size)
{
    unsigned int *bytecode = (unsigned int *)data;
    unsigned int i, j, n;

    size /= sizeof(*bytecode);
    i = 0;
    while (i < size)
    {
        n = min(size - i, 8);
        for (j = 0; j < n; ++j)
            TRACE("0x%08x,", bytecode[i + j]);
        i += n;
        TRACE("\n");
    }
}

static unsigned int *find_bytecode_comment(unsigned int *ptr, unsigned int count,
        unsigned int fourcc, unsigned int *size)
{
    /* Provide at least one value in comment section on non-NULL return. */
    while (count > 2 && (*ptr & 0xffff) == 0xfffe)
    {
        unsigned int section_size;

        section_size = (*ptr >> 16);
        if (!section_size || section_size + 1 > count)
            break;
        if (*(ptr + 1) == fourcc)
        {
            *size = section_size;
            return ptr + 2;
        }
        count -= section_size + 1;
        ptr += section_size + 1;
    }
    return NULL;
}

static unsigned int *parse_pres_arg(unsigned int *ptr, unsigned int count, struct d3dx_pres_operand *opr)
{
    static const enum pres_reg_tables reg_table[8] =
    {
        PRES_REGTAB_COUNT, PRES_REGTAB_IMMED, PRES_REGTAB_CONST, PRES_REGTAB_COUNT,
        PRES_REGTAB_OCONST, PRES_REGTAB_OBCONST, PRES_REGTAB_OICONST, PRES_REGTAB_TEMP
    };

    if (count < 3)
    {
        WARN("Byte code buffer ends unexpectedly.\n");
        return NULL;
    }

    if (*ptr)
    {
        FIXME("Relative addressing not supported yet, word %#x.\n", *ptr);
        return NULL;
    }
    ++ptr;

    if (*ptr >= ARRAY_SIZE(reg_table) || reg_table[*ptr] == PRES_REGTAB_COUNT)
    {
        FIXME("Unsupported register table %#x.\n", *ptr);
        return NULL;
    }
    opr->table = reg_table[*ptr++];
    opr->offset = *ptr++;

    if (opr->table == PRES_REGTAB_OBCONST)
        opr->offset /= 4;
    return ptr;
}

static unsigned int *parse_pres_ins(unsigned int *ptr, unsigned int count, struct d3dx_pres_ins *ins)
{
    unsigned int ins_code, ins_raw;
    unsigned int input_count;
    unsigned int i;

    if (count < 2)
    {
        WARN("Byte code buffer ends unexpectedly.\n");
        return NULL;
    }

    ins_raw = *ptr++;
    ins_code = (ins_raw & PRES_OPCODE_MASK) >> PRES_OPCODE_SHIFT;
    ins->component_count = ins_raw & PRES_NCOMP_MASK;
    ins->scalar_op = !!(ins_raw & PRES_SCALAR_FLAG);

    if (ins->component_count < 1 || ins->component_count > 4)
    {
        FIXME("Unsupported number of components %u.\n", ins->component_count);
        return NULL;
    }
    input_count = *ptr++;
    count -= 2;
    for (i = 0; i < ARRAY_SIZE(pres_op_info); ++i)
        if (ins_code == pres_op_info[i].opcode)
            break;
    if (i == ARRAY_SIZE(pres_op_info))
    {
        FIXME("Unknown opcode %#x, raw %#x.\n", ins_code, ins_raw);
        return NULL;
    }
    ins->op = i;
    if (input_count > ARRAY_SIZE(ins->inputs) || input_count != pres_op_info[i].input_count)
    {
        FIXME("Actual input args %u, expected %u, instruction %s.\n", input_count,
                pres_op_info[i].input_count, pres_op_info[i].mnem);
        return NULL;
    }
    for (i = 0; i < input_count; ++i)
    {
        unsigned int *p;

        p = parse_pres_arg(ptr, count, &ins->inputs[i]);
        if (!p)
            return NULL;
        count -= p - ptr;
        ptr = p;
    }
    ptr = parse_pres_arg(ptr, count, &ins->output);
    return ptr;
}

static HRESULT get_constants_desc(unsigned int *byte_code, struct d3dx_const_tab *out, struct d3dx9_base_effect *base)
{
    ID3DXConstantTable *ctab;
    D3DXCONSTANT_DESC *cdesc;
    struct d3dx_parameter **inputs_param;
    D3DXCONSTANTTABLE_DESC desc;
    HRESULT hr;
    D3DXHANDLE hc;
    unsigned int i;
    unsigned int count;

    out->inputs = cdesc = NULL;
    out->ctab = NULL;
    out->inputs_param = NULL;
    out->input_count = 0;
    inputs_param = NULL;
    hr = D3DXGetShaderConstantTable(byte_code, &ctab);
    if (FAILED(hr) || !ctab)
    {
        TRACE("Could not get CTAB data, hr %#x.\n", hr);
        /* returning OK, shaders and preshaders without CTAB are valid */
        return D3D_OK;
    }
    hr = ID3DXConstantTable_GetDesc(ctab, &desc);
    if (FAILED(hr))
    {
        FIXME("Could not get CTAB desc, hr %#x.\n", hr);
        goto err_out;
    }

    cdesc = HeapAlloc(GetProcessHeap(), 0, sizeof(*cdesc) * desc.Constants);
    inputs_param = HeapAlloc(GetProcessHeap(), 0, sizeof(*inputs_param) * desc.Constants);
    if (!cdesc || !inputs_param)
    {
        hr = E_OUTOFMEMORY;
        goto err_out;
    }

    for (i = 0; i < desc.Constants; ++i)
    {
        hc = ID3DXConstantTable_GetConstant(ctab, NULL, i);
        if (!hc)
        {
            FIXME("Null constant handle.\n");
            goto err_out;
        }
        count = 1;
        hr = ID3DXConstantTable_GetConstantDesc(ctab, hc, &cdesc[i], &count);
        if (FAILED(hr))
        {
            FIXME("Could not get constant desc, hr %#x.\n", hr);
            goto err_out;
        }
        inputs_param[i] = get_parameter_by_name(base, NULL, cdesc[i].Name);
        if (cdesc[i].Class == D3DXPC_OBJECT)
            TRACE("Object %s, parameter %p.\n", cdesc[i].Name, inputs_param[i]);
        else if (!inputs_param[i])
            ERR("Could not find parameter %s in effect.\n", cdesc[i].Name);
    }
    out->input_count = desc.Constants;
    out->inputs = cdesc;
    out->inputs_param = inputs_param;
    out->ctab = ctab;
    return D3D_OK;

err_out:
    HeapFree(GetProcessHeap(), 0, cdesc);
    HeapFree(GetProcessHeap(), 0, inputs_param);
    if (ctab)
        ID3DXConstantTable_Release(ctab);
    return hr;
}

static void update_table_size(unsigned int *table_sizes, unsigned int table, unsigned int max_register)
{
    if (table < PRES_REGTAB_COUNT)
        table_sizes[table] = max(table_sizes[table], max_register + 1);
}

static void update_table_sizes_consts(unsigned int *table_sizes, struct d3dx_const_tab *ctab)
{
    unsigned int i, table, max_register;

    for (i = 0; i < ctab->input_count; ++i)
    {
        if (!ctab->inputs[i].RegisterCount)
            continue;
        max_register = ctab->inputs[i].RegisterIndex + ctab->inputs[i].RegisterCount - 1;
        table = ctab->regset2table[ctab->inputs[i].RegisterSet];
        update_table_size(table_sizes, table, max_register);
    }
}

static HRESULT parse_preshader(struct d3dx_preshader *pres, unsigned int *ptr, unsigned int count, struct d3dx9_base_effect *base)
{
    unsigned int *p;
    unsigned int i, j, const_count;
    double *dconst;
    HRESULT hr;
    unsigned int saved_word;
    unsigned int section_size;

    TRACE("Preshader version %#x.\n", *ptr & 0xffff);

    if (!count)
    {
        WARN("Unexpected end of byte code buffer.\n");
        return D3DXERR_INVALIDDATA;
    }

    p = find_bytecode_comment(ptr + 1, count - 1, FOURCC_CLIT, &section_size);
    if (p)
    {
        const_count = *p++;
        if (const_count > (section_size - 1) / (sizeof(double) / sizeof(unsigned int)))
        {
            WARN("Byte code buffer ends unexpectedly.\n");
            return D3DXERR_INVALIDDATA;
        }
        dconst = (double *)p;
    }
    else
    {
        const_count = 0;
        dconst = NULL;
    }
    TRACE("%u double constants.\n", const_count);

    p = find_bytecode_comment(ptr + 1, count - 1, FOURCC_FXLC, &section_size);
    if (!p)
    {
        WARN("Could not find preshader code.\n");
        return D3D_OK;
    }
    pres->ins_count = *p++;
    --section_size;
    if (pres->ins_count > UINT_MAX / sizeof(*pres->ins))
    {
        WARN("Invalid instruction count %u.\n", pres->ins_count);
        return D3DXERR_INVALIDDATA;
    }
    TRACE("%u instructions.\n", pres->ins_count);
    pres->ins = HeapAlloc(GetProcessHeap(), HEAP_ZERO_MEMORY, sizeof(*pres->ins) * pres->ins_count);
    if (!pres->ins)
        return E_OUTOFMEMORY;
    for (i = 0; i < pres->ins_count; ++i)
    {
        unsigned int *ptr_next;

        ptr_next = parse_pres_ins(p, section_size, &pres->ins[i]);
        if (!ptr_next)
            return D3DXERR_INVALIDDATA;
        section_size -= ptr_next - p;
        p = ptr_next;
    }

    saved_word = *ptr;
    *ptr = 0xfffe0000;
    hr = get_constants_desc(ptr, &pres->inputs, base);
    *ptr = saved_word;
    if (FAILED(hr))
        return hr;

    pres->inputs.regset2table = pres_regset2table;

    pres->regs.table_sizes[PRES_REGTAB_IMMED] = const_count;

    for (i = 0; i < pres->ins_count; ++i)
    {
        for (j = 0; j < pres_op_info[pres->ins[i].op].input_count; ++j)
            update_table_size(pres->regs.table_sizes, pres->ins[i].inputs[j].table,
                    get_reg_offset(pres->ins[i].inputs[j].table,
                    pres->ins[i].inputs[j].offset + pres->ins[i].component_count - 1));

        update_table_size(pres->regs.table_sizes, pres->ins[i].output.table,
                get_reg_offset(pres->ins[i].output.table,
                pres->ins[i].output.offset + pres->ins[i].component_count - 1));
    }
    update_table_sizes_consts(pres->regs.table_sizes, &pres->inputs);
    if (FAILED(regstore_alloc_table(&pres->regs, PRES_REGTAB_IMMED)))
        return E_OUTOFMEMORY;
    regstore_set_values(&pres->regs, PRES_REGTAB_IMMED, dconst, 0, const_count);

    return D3D_OK;
}

void d3dx_create_param_eval(struct d3dx9_base_effect *base_effect, void *byte_code, unsigned int byte_code_size,
        D3DXPARAMETER_TYPE type, struct d3dx_param_eval **peval_out)
{
    struct d3dx_param_eval *peval;
    unsigned int *ptr;
    HRESULT hr;
    unsigned int i;
    BOOL shader;
    unsigned int count, pres_size;

    TRACE("base_effect %p, byte_code %p, byte_code_size %u, type %u, peval_out %p.\n",
            base_effect, byte_code, byte_code_size, type, peval_out);

    count = byte_code_size / sizeof(unsigned int);
    if (!byte_code || !count)
    {
        *peval_out = NULL;
        return;
    }

    peval = HeapAlloc(GetProcessHeap(), HEAP_ZERO_MEMORY, sizeof(*peval));
    if (!peval)
        goto err_out;

    peval->param_type = type;
    switch (type)
    {
        case D3DXPT_VERTEXSHADER:
        case D3DXPT_PIXELSHADER:
            shader = TRUE;
            break;
        default:
            shader = FALSE;
            break;
    }
    peval->shader_inputs.regset2table = shad_regset2table;

    ptr = (unsigned int *)byte_code;
    if (shader)
    {
        if ((*ptr & 0xfffe0000) != 0xfffe0000)
        {
            FIXME("Invalid shader signature %#x.\n", *ptr);
            goto err_out;
        }
        TRACE("Shader version %#x.\n", *ptr & 0xffff);

        if (FAILED(hr = get_constants_desc(ptr, &peval->shader_inputs, base_effect)))
        {
            FIXME("Could not get shader constant table, hr %#x.\n", hr);
            goto err_out;
        }
        update_table_sizes_consts(peval->pres.regs.table_sizes, &peval->shader_inputs);
        ptr = find_bytecode_comment(ptr + 1, count - 1, FOURCC_PRES, &pres_size);
        if (!ptr)
            TRACE("No preshader found.\n");
    }
    else
    {
        pres_size = count;
    }

    if (ptr && FAILED(parse_preshader(&peval->pres, ptr, pres_size, base_effect)))
    {
        FIXME("Failed parsing preshader, byte code for analysis follows.\n");
        dump_bytecode(byte_code, byte_code_size);
        goto err_out;
    }

    for (i = PRES_REGTAB_FIRST_SHADER; i < PRES_REGTAB_COUNT; ++i)
    {
        if (FAILED(regstore_alloc_table(&peval->pres.regs, i)))
            goto err_out;
    }

    if (TRACE_ON(d3dx))
        dump_bytecode(byte_code, byte_code_size);

    *peval_out = peval;
    TRACE("Created parameter evaluator %p.\n", *peval_out);
    return;

err_out:
    FIXME("Error creating parameter evaluator.\n");
    d3dx_free_param_eval(peval);
    *peval_out = NULL;
}

static void d3dx_free_const_tab(struct d3dx_const_tab *ctab)
{
    HeapFree(GetProcessHeap(), 0, ctab->inputs);
    HeapFree(GetProcessHeap(), 0, ctab->inputs_param);
    if (ctab->ctab)
        ID3DXConstantTable_Release(ctab->ctab);
}

static void d3dx_free_preshader(struct d3dx_preshader *pres)
{
    HeapFree(GetProcessHeap(), 0, pres->ins);

    regstore_free_tables(&pres->regs);
    d3dx_free_const_tab(&pres->inputs);
}

void d3dx_free_param_eval(struct d3dx_param_eval *peval)
{
    TRACE("peval %p.\n", peval);

    if (!peval)
        return;

    d3dx_free_preshader(&peval->pres);
    d3dx_free_const_tab(&peval->shader_inputs);
    HeapFree(GetProcessHeap(), 0, peval);
}