#include "dolphin/DVDPriv.h"
#include "dolphin/os.h"
#include "dolphin/os/OSBootInfo.h"

typedef struct FSTEntry FSTEntry;

struct FSTEntry {
  unsigned int isDirAndStringOff;
  unsigned int parentOrPosition;
  unsigned int nextEntryOrLength;
};

static OSBootInfo* BootInfo;
static FSTEntry* FstStart;
static char* FstStringStart;
static u32 MaxEntryNum;
static u32 currentDirectory = 0;
OSThreadQueue __DVDThreadQueue;
u32 __DVDLongFileNameFlag = 0;

static void cbForReadAsync(s32 result, DVDCommandBlock* block);
static void cbForReadSync(s32 result, DVDCommandBlock* block);
static void cbForSeekAsync(s32 result, DVDCommandBlock* block);
static void cbForSeekSync(s32 result, DVDCommandBlock* block);
static void cbForPrepareStreamAsync(s32 result, DVDCommandBlock* block);
static void cbForPrepareStreamSync(s32 result, DVDCommandBlock* block);

void __DVDFSInit() {
  BootInfo = (OSBootInfo*)OSPhysicalToCached(0);
  FstStart = (FSTEntry*)BootInfo->FSTLocation;

  if (FstStart) {
    MaxEntryNum = FstStart[0].nextEntryOrLength;
    FstStringStart = (char*)&(FstStart[MaxEntryNum]);
  }
}

/* For convenience */
#define entryIsDir(i) (((FstStart[i].isDirAndStringOff & 0xff000000) == 0) ? FALSE : TRUE)
#define stringOff(i) (FstStart[i].isDirAndStringOff & ~0xff000000)
#define parentDir(i) (FstStart[i].parentOrPosition)
#define nextDir(i) (FstStart[i].nextEntryOrLength)
#define filePosition(i) (FstStart[i].parentOrPosition)
#define fileLength(i) (FstStart[i].nextEntryOrLength)

static BOOL isSame(const char* path, const char* string) {
  while (*string != '\0') {
    if (tolower(*path++) != tolower(*string++)) {
      return FALSE;
    }
  }

  if ((*path == '/') || (*path == '\0')) {
    return TRUE;
  }

  return FALSE;
}

s32 DVDConvertPathToEntrynum(char* pathPtr) {
  const char* ptr;
  char* stringPtr;
  BOOL isDir;
  u32 length;
  u32 dirLookAt;
  u32 i;
  const char* origPathPtr = pathPtr;
  const char* extentionStart;
  BOOL illegal;
  BOOL extention;

  dirLookAt = currentDirectory;

  while (1) {

    if (*pathPtr == '\0') {
      return (s32)dirLookAt;
    } else if (*pathPtr == '/') {
      dirLookAt = 0;
      pathPtr++;
      continue;
    } else if (*pathPtr == '.') {
      if (*(pathPtr + 1) == '.') {
        if (*(pathPtr + 2) == '/') {
          dirLookAt = parentDir(dirLookAt);
          pathPtr += 3;
          continue;
        } else if (*(pathPtr + 2) == '\0') {
          return (s32)parentDir(dirLookAt);
        }
      } else if (*(pathPtr + 1) == '/') {
        pathPtr += 2;
        continue;
      } else if (*(pathPtr + 1) == '\0') {
        return (s32)dirLookAt;
      }
    }

    if (__DVDLongFileNameFlag == 0) {
      extention = FALSE;
      illegal = FALSE;

      for (ptr = pathPtr; (*ptr != '\0') && (*ptr != '/'); ptr++) {
        if (*ptr == '.') {
          if ((ptr - pathPtr > 8) || (extention == TRUE)) {
            illegal = TRUE;
            break;
          }
          extention = TRUE;
          extentionStart = ptr + 1;

        } else if (*ptr == ' ')
          illegal = TRUE;
      }

      if ((extention == TRUE) && (ptr - extentionStart > 3))
        illegal = TRUE;

      if (illegal)
        OSPanic(__FILE__, 379,
                "DVDConvertEntrynumToPath(possibly DVDOpen or DVDChangeDir or DVDOpenDir): "
                "specified directory or file (%s) doesn't match standard 8.3 format. This is a "
                "temporary restriction and will be removed soon\n",
                origPathPtr);
    } else {
      for (ptr = pathPtr; (*ptr != '\0') && (*ptr != '/'); ptr++)
        ;
    }

    isDir = (*ptr == '\0') ? FALSE : TRUE;
    length = (u32)(ptr - pathPtr);

    ptr = pathPtr;

    for (i = dirLookAt + 1; i < nextDir(dirLookAt); i = entryIsDir(i) ? nextDir(i) : (i + 1)) {
      if ((entryIsDir(i) == FALSE) && (isDir == TRUE)) {
        continue;
      }

      stringPtr = FstStringStart + stringOff(i);

      if (isSame(ptr, stringPtr) == TRUE) {
        goto next_hier;
      }
    }

    return -1;

  next_hier:
    if (!isDir) {
      return (s32)i;
    }

    dirLookAt = i;
    pathPtr += length + 1;
  }
}

BOOL DVDFastOpen(s32 entrynum, DVDFileInfo* fileInfo) {
  if ((entrynum < 0) || (entrynum >= MaxEntryNum) || entryIsDir(entrynum)) {
    return FALSE;
  }

  fileInfo->startAddr = filePosition(entrynum);
  fileInfo->length = fileLength(entrynum);
  fileInfo->callback = (DVDCallback)NULL;
  fileInfo->cb.state = DVD_STATE_END;

  return TRUE;
}

BOOL DVDOpen(char* fileName, DVDFileInfo* fileInfo) {
  s32 entry;
  char currentDir[128];

  entry = DVDConvertPathToEntrynum(fileName);

  if (0 > entry) {
    DVDGetCurrentDir(currentDir, 128);
    OSReport("Warning: DVDOpen(): file '%s' was not found under %s.\n", fileName, currentDir);
    return FALSE;
  }

  if (entryIsDir(entry)) {
    return FALSE;
  }

  fileInfo->startAddr = filePosition(entry);
  fileInfo->length = fileLength(entry);
  fileInfo->callback = (DVDCallback)NULL;
  fileInfo->cb.state = DVD_STATE_END;

  return TRUE;
}

#ifdef FULL_FRANK
BOOL DVDClose(DVDFileInfo* fileInfo) {
  DVDCancel(&(fileInfo->cb));
  return TRUE;
}
#else
/* clang-format off */
#pragma push
#pragma optimization_level 0
#pragma optimizewithasm off
asm BOOL DVDClose(DVDFileInfo* fileInfo) {
  nofralloc
  mflr r0
  stw r0, 4(r1)
  stwu r1, -8(r1)
  bl DVDCancel
  li r3, 1
  lwz r0, 0xc(r1)
  addi r1, r1, 8
  mtlr r0
  blr
}
#pragma pop
#endif

static u32 myStrncpy(char* dest, char* src, u32 maxlen) {
  u32 i = maxlen;

  while ((i > 0) && (*src != 0)) {
    *dest++ = *src++;
    i--;
  }

  return (maxlen - i);
}

static u32 entryToPath(u32 entry, char* path, u32 maxlen) {
  char* name;
  u32 loc;

  if (entry == 0) {
    return 0;
  }

  name = FstStringStart + stringOff(entry);

  loc = entryToPath(parentDir(entry), path, maxlen);

  if (loc == maxlen) {
    return loc;
  }

  *(path + loc++) = '/';

  loc += myStrncpy(path + loc, name, maxlen - loc);

  return loc;
}

static BOOL DVDConvertEntrynumToPath(s32 entrynum, char* path, u32 maxlen) {
  u32 loc;

  loc = entryToPath((u32)entrynum, path, maxlen);

  if (loc == maxlen) {
    path[maxlen - 1] = '\0';
    return FALSE;
  }

  if (entryIsDir(entrynum)) {
    if (loc == maxlen - 1) {
      path[loc] = '\0';
      return FALSE;
    }

    path[loc++] = '/';
  }

  path[loc] = '\0';
  return TRUE;
}

BOOL DVDGetCurrentDir(char* path, u32 maxlen) {
  return DVDConvertEntrynumToPath((s32)currentDirectory, path, maxlen);
}

BOOL DVDChangeDir(char* dirName) {
  s32 entry;
  entry = DVDConvertPathToEntrynum(dirName);
  if ((entry < 0) || (entryIsDir(entry) == FALSE)) {
    return FALSE;
  }

  currentDirectory = (u32)entry;

  return TRUE;
}

BOOL DVDReadAsyncPrio(DVDFileInfo* fileInfo, void* addr, s32 length, s32 offset,
                      DVDCallback callback, s32 prio) {

  if (!((0 <= offset) && (offset < fileInfo->length))) {
    OSPanic(__FILE__, 742, "DVDReadAsync(): specified area is out of the file  ");
  }

  if (!((0 <= offset + length) && (offset + length < fileInfo->length + DVD_MIN_TRANSFER_SIZE))) {
    OSPanic(__FILE__, 748, "DVDReadAsync(): specified area is out of the file  ");
  }

  fileInfo->callback = callback;
  DVDReadAbsAsyncPrio(&(fileInfo->cb), addr, length, (s32)(fileInfo->startAddr + offset),
                      cbForReadAsync, prio);

  return TRUE;
}
#ifndef offsetof
#define offsetof(type, memb) ((u32) & ((type*)0)->memb)
#endif

static void cbForReadAsync(s32 result, DVDCommandBlock* block) {
  DVDFileInfo* fileInfo;

  fileInfo = (DVDFileInfo*)((char*)block - offsetof(DVDFileInfo, cb));
  if (fileInfo->callback) {
    (fileInfo->callback)(result, fileInfo);
  }
}

/* This is based on the revolution SDK, these may not match in all cases I have also left the line numbers at 0 */
s32 DVDReadPrio(DVDFileInfo* fileInfo, void* addr, s32 length, s32 offset, s32 prio) {
  BOOL result;
  DVDCommandBlock* block;
  s32 state;
  BOOL enabled;
  s32 retVal;

  if (!((0 <= offset) && (offset <= fileInfo->length))) {
    OSPanic(__FILE__, 0, "DVDRead(): specified area is out of the file  ");
  }

  if (!((0 <= offset + length) && (offset + length < fileInfo->length + DVD_MIN_TRANSFER_SIZE))) {
    OSPanic(__FILE__, 0, "DVDRead(): specified area is out of the file  ");
  }

  block = &(fileInfo->cb);

  result = DVDReadAbsAsyncPrio(block, addr, length, (s32)(fileInfo->startAddr + offset),
                               cbForReadSync, prio);

  if (result == FALSE) {
    return -1;
  }

  enabled = OSDisableInterrupts();

  while(1) {
    state = ((volatile DVDCommandBlock*)block)->state;

    if (state == DVD_STATE_END) {
      retVal = (s32)block->transferredSize;
      break;
    }
    if (state == DVD_STATE_FATAL_ERROR) {
      retVal = DVD_RESULT_FATAL_ERROR;
      break;
    }
    if (state == DVD_STATE_CANCELED) {
      retVal = DVD_RESULT_CANCELED;
      break;
    }

    OSSleepThread(&__DVDThreadQueue);
  }

  OSRestoreInterrupts(enabled);
  return retVal;
}

/* This is based on the revolution SDK, these may not match in all cases */
static void cbForReadSync(s32 result, DVDCommandBlock* block) { OSWakeupThread(&__DVDThreadQueue); }
/* This is based on the revolution SDK, these may not match in all cases */
BOOL DVDSeekAsyncPrio(DVDFileInfo* fileInfo, s32 offset, DVDCallback callback, s32 prio) {
  if (!((0 <= offset) && (offset <= fileInfo->length))) {
    OSPanic(__FILE__, 0, "DVDSeek(): offset is out of the file  ");
  }

  fileInfo->callback = callback;
  DVDSeekAbsAsyncPrio(&(fileInfo->cb), (s32)(fileInfo->startAddr + offset), cbForSeekAsync,
                      prio);

  return TRUE;
}
/* This is based on the revolution SDK, these may not match in all cases */
static void cbForSeekAsync(s32 result, DVDCommandBlock* block) {
  DVDFileInfo* fileInfo;

  fileInfo = (DVDFileInfo*)((char*)block - offsetof(DVDFileInfo, cb));

  if (fileInfo->callback) {
    (fileInfo->callback)(result, fileInfo);
  }
}
/* This is based on the revolution SDK, these may not match in all cases */
s32 DVDSeekPrio(DVDFileInfo* fileInfo, s32 offset, s32 prio) {
  BOOL result;
  DVDCommandBlock* block;
  s32 state;
  BOOL enabled;
  s32 retVal;

  block = &(fileInfo->cb);

  result =
      DVDSeekAbsAsyncPrio(block, (s32)(fileInfo->startAddr + offset), cbForSeekSync, prio);

  if (result == FALSE) {
    return -1;
  }

  enabled = OSDisableInterrupts();

  while (1) {
    state = ((volatile DVDCommandBlock*)block)->state;

    if (state == DVD_STATE_END) {
      retVal = 0;
      break;
    }
    if (state == DVD_STATE_FATAL_ERROR) {
      retVal = DVD_RESULT_FATAL_ERROR;
      break;
    }
    if (state == DVD_STATE_CANCELED) {
      retVal = DVD_RESULT_CANCELED;
      break;
    }

    OSSleepThread(&__DVDThreadQueue);
  }

  OSRestoreInterrupts(enabled);
  return retVal;
}
/* This is based on the revolution SDK, these may not match in all cases */
static void cbForSeekSync(s32 result, DVDCommandBlock* block) { OSWakeupThread(&__DVDThreadQueue); }

/* This is based on the revolution SDK, these may not match in all cases */
s32 DVDGetFileInfoStatus(DVDFileInfo* fileInfo) {
  return DVDGetCommandBlockStatus(&fileInfo->cb);
}

/* This is based on the revolution SDK, these may not match in all cases */
BOOL DVDFastOpenDir(s32 entrynum, DVDDir* dir) {

  if ((entrynum < 0) || (entrynum >= MaxEntryNum) || !entryIsDir(entrynum)) {
    return FALSE;
  }

  dir->entryNum = (u32)entrynum;
  dir->location = (u32)entrynum + 1;
  dir->next = nextDir(entrynum);

  return TRUE;
}

/* This is based on the revolution SDK, these may not match in all cases */
BOOL DVDOpenDir(char* dirName, DVDDir* dir) {
  s32 entry;
  char currentDir[128];
  entry = DVDConvertPathToEntrynum(dirName);

  if (entry < 0) {
    DVDGetCurrentDir(currentDir, 128);
    OSReport("Warning: DVDOpenDir(): file '%s' was not found under %s.\n", dirName, currentDir);
    return FALSE;
  }

  if (!entryIsDir(entry)) {
    return FALSE;
  }

  dir->entryNum = (u32)entry;
  dir->location = (u32)entry + 1;
  dir->next = nextDir(entry);

  return TRUE;
}

BOOL DVDReadDir(DVDDir* dir, DVDDirEntry* dirent) {
  u32 loc = dir->location;
  if ((loc <= dir->entryNum) || (dir->next <= loc))
    return FALSE;

  dirent->entryNum = loc;
  dirent->isDir = entryIsDir(loc);
  dirent->name = FstStringStart + stringOff(loc);

  dir->location = entryIsDir(loc) ? nextDir(loc) : (loc + 1);

  return TRUE;
}

/* This is based on the revolution SDK, these may not match in all cases */
BOOL DVDCloseDir(DVDDir* dir) { return TRUE; }

/* This is based on the revolution SDK, these may not match in all cases */
void DVDRewindDir(DVDDir* dir) { dir->location = dir->entryNum + 1; }

/* This is based on the revolution SDK, these may not match in all cases */
void* DVDGetFSTLocation(void) { return BootInfo->FSTLocation; }

#define RoundUp32KB(x) (((u32)(x) + 32 * 1024 - 1) & ~(32 * 1024 - 1))
#define Is32KBAligned(x) (((u32)(x) & (32 * 1024 - 1)) == 0)

BOOL DVDPrepareStreamAsync(DVDFileInfo* fileInfo, u32 length, u32 offset, DVDCallback callback) {
  u32 start;

  start = fileInfo->startAddr + offset;

  if (!Is32KBAligned(start)) {
    OSPanic(__FILE__, 1189,
            "DVDPrepareStreamAsync(): Specified start address (filestart(0x%x) + offset(0x%x)) is "
            "not 32KB aligned",
            fileInfo->startAddr, offset);
  }

  if (length == 0)
    length = fileInfo->length - offset;

  if (!Is32KBAligned(length)) {
    OSPanic(__FILE__, 1199,
            "DVDPrepareStreamAsync(): Specified length (0x%x) is not a multiple of 32768(32*1024)",
            length);
  }

  if (!((offset < fileInfo->length) && (offset + length <= fileInfo->length))) {
    OSPanic(__FILE__, 1207,
            "DVDPrepareStreamAsync(): The area specified (offset(0x%x), length(0x%x)) is out of "
            "the file",
            offset, length);
  }

  fileInfo->callback = callback;
  return DVDPrepareStreamAbsAsync(&(fileInfo->cb), length, fileInfo->startAddr + offset,
                                  cbForPrepareStreamAsync);
}

static void cbForPrepareStreamAsync(s32 result, DVDCommandBlock* block) {
  DVDFileInfo* fileInfo;

  fileInfo = (DVDFileInfo*)((char*)block - offsetof(DVDFileInfo, cb));

  if (fileInfo->callback) {
    (fileInfo->callback)(result, fileInfo);
  }
}

/* This is based on the revolution SDK, these may not match in all cases */
s32 DVDPrepareStream(DVDFileInfo* fileInfo, u32 length, u32 offset) {
  BOOL result;
  DVDCommandBlock* block;
  s32 state;
  BOOL enabled;
  s32 retVal;
  u32 start;
  start = fileInfo->startAddr + offset;

  if (!Is32KBAligned(start)) {
    OSPanic(__FILE__, 0,
            "DVDPrepareStream(): Specified start address (filestart(0x%x) + offset(0x%x)) is not "
            "32KB aligned",
            fileInfo->startAddr, offset);
  }

  if (length == 0)
    length = fileInfo->length - offset;

  if (!Is32KBAligned(length)) {
    OSPanic(__FILE__, 0,
            "DVDPrepareStream(): Specified length (0x%x) is not a multiple of 32768(32*1024)",
            length);
  }

  if (!((offset <= fileInfo->length) && (offset + length <= fileInfo->length))) {
    OSPanic(
        __FILE__, 0,
        "DVDPrepareStream(): The area specified (offset(0x%x), length(0x%x)) is out of the file",
        offset, length);
  }

  block = &(fileInfo->cb);
  result = DVDPrepareStreamAbsAsync(block, length, start, cbForPrepareStreamSync);

  if (result == FALSE) {
    return -1;
  }

  enabled = OSDisableInterrupts();

  while(1) {
    state = ((volatile DVDCommandBlock*)block)->state;

    if (state == DVD_STATE_END) {
      retVal = 0;
      break;
    }
    if (state == DVD_STATE_FATAL_ERROR) {
      retVal = DVD_RESULT_FATAL_ERROR;
      break;
    }
    if (state == DVD_STATE_CANCELED) {
      retVal = DVD_RESULT_CANCELED;
      break;
    }

    OSSleepThread(&__DVDThreadQueue);
  }

  OSRestoreInterrupts(enabled);
  return retVal;
}

/* This is based on the revolution SDK, these may not match in all cases */
static void cbForPrepareStreamSync(s32 result, DVDCommandBlock* block) {
  OSWakeupThread(&__DVDThreadQueue);
}

/* This is based on the revolution SDK, these may not match in all cases */
s32 DVDGetTransferredSize(DVDFileInfo* fileinfo) {
  s32 bytes;
  DVDCommandBlock* cb;

  cb = &(fileinfo->cb);

  switch (cb->state) {
  case DVD_STATE_END:
  case DVD_STATE_COVER_CLOSED:
  case DVD_STATE_NO_DISK:
  case DVD_STATE_COVER_OPEN:
  case DVD_STATE_WRONG_DISK:
  case DVD_STATE_FATAL_ERROR:
  case DVD_STATE_MOTOR_STOPPED:
  case DVD_STATE_CANCELED:
  case DVD_STATE_RETRY:
    bytes = (s32)cb->transferredSize;
    break;

  case DVD_STATE_WAITING:
    bytes = 0;
    break;

  case DVD_STATE_BUSY:
    bytes = (s32)(cb->transferredSize + (cb->currTransferSize - DVDLowGetLength()));
    break;

  default:
    break;
  }

  return bytes;
}