#include <stdlib.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <errno.h>
#include <fcntl.h>
#include <memory.h>
#include <unistd.h>
#include <string.h>

#include "winbase.h"
#include "aspi.h"
#include "winaspi.h"
#include "options.h"
#include "heap.h"
#include "debugtools.h"
#include "selectors.h"
#include "miscemu.h"
#include "ldt.h"
#include "callback.h"

DEFAULT_DEBUG_CHANNEL(aspi)


/* FIXME!
 * 1) Residual byte length reporting not handled
 * 2) Make this code re-entrant for multithreading
 * 3) Only linux supported so far
 */

#ifdef linux

static ASPI_DEVICE_INFO *ASPI_open_devices = NULL;

static FARPROC16 ASPIChainFunc = NULL;
static WORD HA_Count = 1; /* host adapter count; FIXME: detect it */

static int
ASPI_OpenDevice16(SRB_ExecSCSICmd16 *prb)
{
    int	fd;
    char	idstr[20];
    char	device_str[50];
    ASPI_DEVICE_INFO *curr;

    /* search list of devices to see if we've opened it already.
     * There is not an explicit open/close in ASPI land, so hopefully
     * keeping a device open won't be a problem.
     */

    for (curr = ASPI_open_devices; curr; curr = curr->next) {
	if (curr->hostId == prb->SRB_HaId &&
	    curr->target == prb->SRB_Target &&
	    curr->lun == prb->SRB_Lun) {
	    return curr->fd;
	}
    }

    /* device wasn't cached, go ahead and open it */
    sprintf(idstr, "scsi c%1dt%1dd%1d", prb->SRB_HaId, prb->SRB_Target, prb->SRB_Lun);

    if (!PROFILE_GetWineIniString(idstr, "Device", "", device_str, sizeof(device_str))) {
	TRACE("Trying to open unlisted scsi device %s\n", idstr);
	return -1;
    }

    TRACE("Opening device %s=%s\n", idstr, device_str);

    fd = open(device_str, O_RDWR);
    if (fd == -1) {
	int save_error = errno;
#ifdef HAVE_STRERROR
	ERR("Error opening device %s, error '%s'\n", device_str, strerror(save_error));
#else
    ERR("Error opening device %s, error %d\n", device_str, save_error);
#endif
	return -1;
    }

    /* device is now open */
    curr = HeapAlloc( SystemHeap, 0, sizeof(ASPI_DEVICE_INFO) );
    curr->fd = fd;
    curr->hostId = prb->SRB_HaId;
    curr->target = prb->SRB_Target;
    curr->lun = prb->SRB_Lun;

    /* insert new record at beginning of open device list */
    curr->next = ASPI_open_devices;
    ASPI_open_devices = curr;
    return fd;
}


static void
ASPI_DebugPrintCmd(SRB_ExecSCSICmd16 *prb, UINT16 mode)
{
  BYTE	cmd;
  int	i;
  BYTE *cdb;
  BYTE *lpBuf = 0;

  switch (mode)
  {
      case ASPI_DOS:
	/* translate real mode address */
	if (prb->SRB_BufPointer)
	    lpBuf = (BYTE *)DOSMEM_MapRealToLinear((UINT)prb->SRB_BufPointer);
	break;
      case ASPI_WIN16:
	lpBuf = PTR_SEG_TO_LIN(prb->SRB_BufPointer);
	break;
  }

  switch (prb->CDBByte[0]) {
  case CMD_INQUIRY:
    TRACE("{\n");
    TRACE("\tEVPD: %d\n", prb->CDBByte[1] & 1);
    TRACE("\tLUN: %d\n", (prb->CDBByte[1] & 0xc) >> 1);
    TRACE("\tPAGE CODE: %d\n", prb->CDBByte[2]);
    TRACE("\tALLOCATION LENGTH: %d\n", prb->CDBByte[4]);
    TRACE("\tCONTROL: %d\n", prb->CDBByte[5]);
    TRACE("}\n");
    break;
  case CMD_SCAN_SCAN:
    TRACE("Transfer Length: %d\n", prb->CDBByte[4]);
    break;
  }

  TRACE("Host Adapter: %d\n", prb->SRB_HaId);
  TRACE("Flags: %d\n", prb->SRB_Flags);
  if (TARGET_TO_HOST(prb)) {
    TRACE("\tData transfer: Target to host. Length checked.\n");
  }
  else if (HOST_TO_TARGET(prb)) {
    TRACE("\tData transfer: Host to target. Length checked.\n");
  }
  else if (NO_DATA_TRANSFERED(prb)) {
    TRACE("\tData transfer: none\n");
  }
  else {
    WARN("\tTransfer by scsi cmd. Length not checked\n");
  }

  TRACE("\tResidual byte length reporting %s\n", prb->SRB_Flags & 0x4 ? "enabled" : "disabled");
  TRACE("\tLinking %s\n", prb->SRB_Flags & 0x2 ? "enabled" : "disabled");
  TRACE("\tPosting %s\n", prb->SRB_Flags & 0x1 ? "enabled" : "disabled");
  TRACE("Target: %d\n", prb->SRB_Target);
  TRACE("Lun: %d\n", prb->SRB_Lun);
  TRACE("BufLen: %ld\n", prb->SRB_BufLen);
  TRACE("SenseLen: %d\n", prb->SRB_SenseLen);
  TRACE("BufPtr: %lx (%p)\n", prb->SRB_BufPointer, lpBuf);
  TRACE("LinkPointer %lx\n", prb->SRB_Rsvd1);
  TRACE("CDB Length: %d\n", prb->SRB_CDBLen);
  TRACE("POST Proc: %lx\n", (DWORD) prb->SRB_PostProc);
  cdb = &prb->CDBByte[0];
  cmd = prb->CDBByte[0];
  if (TRACE_ON(aspi))
  {
      DPRINTF("CDB buffer[");
      for (i = 0; i < prb->SRB_CDBLen; i++) {
          if (i != 0) DPRINTF(",");
          DPRINTF("%02x", *cdb++);
      }
      DPRINTF("]\n");
  }
}

static void
ASPI_PrintSenseArea16(SRB_ExecSCSICmd16 *prb)
{
  int	i;
  BYTE *cdb;

  if (TRACE_ON(aspi))
  {
      cdb = &prb->CDBByte[0];
      DPRINTF("SenseArea[");
      for (i = 0; i < prb->SRB_SenseLen; i++) {
          if (i) DPRINTF(",");
          DPRINTF("%02x", *cdb++);
      }
      DPRINTF("]\n");
  }
}

static void
ASPI_DebugPrintResult(SRB_ExecSCSICmd16 *prb, UINT16 mode)
{
  BYTE *lpBuf = 0;

  switch (mode)
  {
      case ASPI_DOS:
	/* translate real mode address */
	if (prb->SRB_BufPointer)
	    lpBuf = (BYTE *)DOSMEM_MapRealToLinear((UINT)prb->SRB_BufPointer);
	break;
      case ASPI_WIN16:
	lpBuf = PTR_SEG_TO_LIN(prb->SRB_BufPointer);
	break;
  }

  switch (prb->CDBByte[0]) {
  case CMD_INQUIRY:
    TRACE("Vendor: '%s'\n", lpBuf + INQUIRY_VENDOR);
    break;
  case CMD_TEST_UNIT_READY:
    ASPI_PrintSenseArea16(prb);
    break;
  }
}

static WORD
ASPI_ExecScsiCmd(DWORD ptrPRB, UINT16 mode)
{
  SRB_ExecSCSICmd16 *lpPRB = 0;
  struct sg_header *sg_hd, *sg_reply_hdr;
  int	status;
  BYTE *lpBuf = 0;
  int	in_len, out_len;
  int	error_code = 0;
  int	fd;

  switch (mode)
  {
      case ASPI_DOS:
	if (ptrPRB)
	    lpPRB = (SRB_ExecSCSICmd16 *)DOSMEM_MapRealToLinear(ptrPRB);
	break;
      case ASPI_WIN16:
	lpPRB = PTR_SEG_TO_LIN(ptrPRB);
	break;
  }

  ASPI_DebugPrintCmd(lpPRB, mode);

  fd = ASPI_OpenDevice16(lpPRB);
  if (fd == -1) {
      WARN("Failed: could not open device. Device permissions !?\n");
      lpPRB->SRB_Status = SS_ERR;
      return SS_ERR;
  }

  sg_hd = NULL;
  sg_reply_hdr = NULL;

  lpPRB->SRB_Status = SS_PENDING;

  switch (mode)
  {
      case ASPI_DOS:
	/* translate real mode address */
	if (ptrPRB)
	    lpBuf = (BYTE *)DOSMEM_MapRealToLinear((UINT)lpPRB->SRB_BufPointer);
	break;
      case ASPI_WIN16:
	lpBuf = PTR_SEG_TO_LIN(lpPRB->SRB_BufPointer);
	break;
  }

  if (!lpPRB->SRB_CDBLen) {
      WARN("Failed: lpPRB->SRB_CDBLen = 0.\n");
      lpPRB->SRB_Status = SS_ERR;
      return SS_ERR;
  }

  /* build up sg_header + scsi cmd */
  if (HOST_TO_TARGET(lpPRB)) {
    /* send header, command, and then data */
    in_len = SCSI_OFF + lpPRB->SRB_CDBLen + lpPRB->SRB_BufLen;
    sg_hd = (struct sg_header *) malloc(in_len);
    memset(sg_hd, 0, SCSI_OFF);
    memcpy(sg_hd + 1, &lpPRB->CDBByte[0], lpPRB->SRB_CDBLen);
    if (lpPRB->SRB_BufLen) {
      memcpy(((BYTE *) sg_hd) + SCSI_OFF + lpPRB->SRB_CDBLen, lpBuf, lpPRB->SRB_BufLen);
    }
  }
  else {
    /* send header and command - no data */
    in_len = SCSI_OFF + lpPRB->SRB_CDBLen;
    sg_hd = (struct sg_header *) malloc(in_len);
    memset(sg_hd, 0, SCSI_OFF);
    memcpy(sg_hd + 1, &lpPRB->CDBByte[0], lpPRB->SRB_CDBLen);
  }

  if (TARGET_TO_HOST(lpPRB)) {
    out_len = SCSI_OFF + lpPRB->SRB_BufLen;
    sg_reply_hdr = (struct sg_header *) malloc(out_len);
    memset(sg_reply_hdr, 0, SCSI_OFF);
    sg_hd->reply_len = out_len;
  }
  else {
    out_len = SCSI_OFF;
    sg_reply_hdr = (struct sg_header *) malloc(out_len);
    memset(sg_reply_hdr, 0, SCSI_OFF);
    sg_hd->reply_len = out_len;
  }

  status = write(fd, sg_hd, in_len);
  if (status < 0 || status != in_len) {
      int save_error = errno;

    WARN("Not enough bytes written to scsi device bytes=%d .. %d\n", in_len, status);
    if (status < 0) {
		if (save_error == ENOMEM) {
	    MESSAGE("ASPI: Linux generic scsi driver\n  You probably need to re-compile your kernel with a larger SG_BIG_BUFF value (sg.h)\n  Suggest 130560\n");
	}
#ifdef HAVE_STRERROR
		WARN("error:= '%s'\n", strerror(save_error));
#else
		WARN("error:= %d\n", save_error);
#endif
    }
    goto error_exit;
  }

  status = read(fd, sg_reply_hdr, out_len);
  if (status < 0 || status != out_len) {
    WARN("not enough bytes read from scsi device%d\n", status);
    goto error_exit;
  }

  if (sg_reply_hdr->result != 0) {
    error_code = sg_reply_hdr->result;
    WARN("reply header error (%d)\n", sg_reply_hdr->result);
    goto error_exit;
  }

  if (TARGET_TO_HOST(lpPRB) && lpPRB->SRB_BufLen) {
    memcpy(lpBuf, sg_reply_hdr + 1, lpPRB->SRB_BufLen);
  }

  /* copy in sense buffer to amount that is available in client */
  if (lpPRB->SRB_SenseLen) {
    int sense_len = lpPRB->SRB_SenseLen;
    if (lpPRB->SRB_SenseLen > 16)
      sense_len = 16;
    memcpy(SENSE_BUFFER(lpPRB), &sg_reply_hdr->sense_buffer[0], sense_len);
  }


  lpPRB->SRB_Status = SS_COMP;
  lpPRB->SRB_HaStat = HASTAT_OK;
  lpPRB->SRB_TargStat = STATUS_GOOD;

  /* now do posting */

  if (ASPI_POSTING(lpPRB) && lpPRB->SRB_PostProc) {
    TRACE("Post Routine (%lx) called\n", (DWORD) lpPRB->SRB_PostProc);
    switch (mode)
    {
      case ASPI_DOS:
      {
	SEGPTR spPRB = MapLS(lpPRB);

	Callbacks->CallASPIPostProc(lpPRB->SRB_PostProc, spPRB);	
	UnMapLS(spPRB);
	break;
      }
      case ASPI_WIN16:
        Callbacks->CallASPIPostProc(lpPRB->SRB_PostProc, ptrPRB);
	break;
    }
  }

  free(sg_reply_hdr);
  free(sg_hd);
  ASPI_DebugPrintResult(lpPRB, mode);
  return SS_COMP;
  
error_exit:
  if (error_code == EBUSY) {
      lpPRB->SRB_Status = SS_ASPI_IS_BUSY;
      TRACE("Device busy\n");
  }
  else {
      WARN("Failed\n");
      lpPRB->SRB_Status = SS_ERR;
  }

  /* I'm not sure exactly error codes work here
   * We probably should set lpPRB->SRB_TargStat, SRB_HaStat ?
   */
  WARN("error_exit\n");
  free(sg_reply_hdr);
  free(sg_hd);
  return lpPRB->SRB_Status;
}
#endif


/***********************************************************************
 *             GetASPISupportInfo16   (WINASPI.1)
 */

WORD WINAPI GetASPISupportInfo16()
{
#ifdef linux
    TRACE("GETASPISupportInfo16\n");
    /* high byte SS_COMP - low byte number of host adapters */
    return ((SS_COMP << 8) | HA_Count);
#else
    return ((SS_NO_ASPI << 8) | 0);
#endif
}


DWORD ASPI_SendASPICommand(DWORD ptrSRB, UINT16 mode)
{
#ifdef linux
  LPSRB16 lpSRB = 0;

  switch (mode)
  {
      case ASPI_DOS:
	if (ptrSRB)
	    lpSRB = (LPSRB16)DOSMEM_MapRealToLinear(ptrSRB);
	break;
      case ASPI_WIN16:
	lpSRB = PTR_SEG_TO_LIN(ptrSRB);
	if (ASPIChainFunc)
	{
	    /* This is not the post proc, it's the chain proc this time */
	    DWORD ret = Callbacks->CallASPIPostProc(ASPIChainFunc, ptrSRB);
	    if (ret)
	    {
		lpSRB->inquiry.SRB_Status = SS_INVALID_SRB;
		return ret;
	    }
	}
	break;
  }

  switch (lpSRB->common.SRB_Cmd) {
  case SC_HA_INQUIRY:
    lpSRB->inquiry.SRB_Status = SS_COMP;       /* completed successfully */
    if (lpSRB->inquiry.SRB_55AASignature == 0x55aa) {
	TRACE("Extended request detected (Adaptec's ASPIxDOS).\nWe don't support it at the moment.\n");
    }
    lpSRB->inquiry.SRB_ExtBufferSize = 0x2000; /* bogus value */
    lpSRB->inquiry.HA_Count = HA_Count;
    lpSRB->inquiry.HA_SCSI_ID = 7;             /* not always ID 7 */
    strcat(lpSRB->inquiry.HA_ManagerId, "Wine ASPI16"); /* max 15 chars */
    strcat(lpSRB->inquiry.HA_Identifier, "Wine host"); /* FIXME: return host
adapter name */
    memset(lpSRB->inquiry.HA_Unique, 0, 16); /* default HA_Unique content */
    lpSRB->inquiry.HA_Unique[6] = 0x02; /* Maximum Transfer Length (128K, Byte> 4-7) */
    FIXME("ASPI: Partially implemented SC_HA_INQUIRY for adapter %d.\n", lpSRB->inquiry.SRB_HaId);
    return SS_COMP;
  case SC_GET_DEV_TYPE:
    FIXME("Not implemented SC_GET_DEV_TYPE\n");
    break;
  case SC_EXEC_SCSI_CMD:
    return ASPI_ExecScsiCmd((DWORD)ptrSRB, mode);
    break;
  case SC_RESET_DEV:
    FIXME("Not implemented SC_RESET_DEV\n");
    break;
  default:
    FIXME("Unknown command %d\n", lpSRB->common.SRB_Cmd);
  }
#endif
  return SS_INVALID_SRB;
}


/***********************************************************************
 *             SendASPICommand16   (WINASPI.2)
 */
WORD WINAPI SendASPICommand16(SEGPTR segptr_srb)
{
#ifdef linux
    return ASPI_SendASPICommand(segptr_srb, ASPI_WIN16);
#else
    return 0; 
#endif
}


/***********************************************************************
 *             InsertInASPIChain16   (WINASPI.3)
 */
WORD WINAPI InsertInASPIChain16(BOOL16 remove, FARPROC16 pASPIChainFunc)
{
#ifdef linux
    if (remove == TRUE) /* Remove */
    {
	if (ASPIChainFunc == pASPIChainFunc)
	{
	    ASPIChainFunc = NULL;
	    return SS_COMP;
	}
    }
    else
    if (remove == FALSE) /* Insert */
    {
	if (ASPIChainFunc == NULL)
	{
	    ASPIChainFunc = pASPIChainFunc;
	    return SS_COMP;
	}
    }
#endif
    return SS_ERR;
}


/***********************************************************************
 *             GetASPIDLLVersion16   (WINASPI.4)
 */

DWORD WINAPI GetASPIDLLVersion16()
{
#ifdef linux
	return 2;
#else
	return 0;
#endif
}


void WINAPI ASPI_DOS_func(CONTEXT86 *context)
{
	WORD *stack = CTX_SEG_OFF_TO_LIN(context, SS_reg(context), ESP_reg(context));
	DWORD ptrSRB = *(DWORD *)&stack[2];

	ASPI_SendASPICommand(ptrSRB, ASPI_DOS);

	/* simulate a normal RETF sequence as required by DPMI CallRMProcFar */
	EIP_reg(context) = *(stack++);
	CS_reg(context)  = *(stack++);
	ESP_reg(context) += 2*sizeof(WORD);
}


/* returns the address of a real mode callback to ASPI_DOS_func() */
void ASPI_DOS_HandleInt(CONTEXT86 *context)
{
#ifdef linux
	FARPROC16 *p = (FARPROC16 *)CTX_SEG_OFF_TO_LIN(context, DS_reg(context), EDX_reg(context));
	if ((CX_reg(context) == 4) || (CX_reg(context) == 5))
	{
	*p = DPMI_AllocInternalRMCB(ASPI_DOS_func);
	TRACE("allocated real mode proc %p\n", *p);
	    AX_reg(context) = CX_reg(context);
	}
	else
#endif
	SET_CFLAG(context);
}