#include <3ds.h>
#include "ifile.h"

Result IFile_Open(IFile *file, FS_ArchiveID archiveId, FS_Path archivePath, FS_Path filePath, u32 flags)
{
  Result res;

  res = FSUSER_OpenFileDirectly(&file->handle, archiveId, archivePath, filePath, flags, 0);
  file->pos = 0;
  file->size = 0;
  return res;
}

Result IFile_OpenFromArchive(IFile *file, FS_Archive archive, FS_Path filePath, u32 flags)
{
  Result res;

  res = FSUSER_OpenFile(&file->handle, archive, filePath, flags, 0);
  file->pos = 0;
  file->size = 0;
  return res;
}

Result IFile_Close(IFile *file)
{
  Result res = file->handle != 0 ? FSFILE_Close(file->handle) : 0;
  file->handle = 0;
  return res;
}

Result IFile_GetSize(IFile *file, u64 *size)
{
  Result res;

  res = FSFILE_GetSize(file->handle, size);
  if (R_SUCCEEDED(res)) file->size = *size;
  return res;
}

Result IFile_SetSize(IFile *file, u64 size)
{
  Result res;

  res = FSFILE_SetSize(file->handle, size);
  if (R_SUCCEEDED(res)) file->size = size;
  return res;
}

Result IFile_Read(IFile *file, u64 *total, void *buffer, u32 len)
{
  u32 read;
  u32 left;
  char *buf;
  u64 cur;
  Result res;

  if (len == 0)
  {
    *total = 0;
    return 0;
  }

  buf = (char *)buffer;
  cur = 0;
  left = len;
  while (1)
  {
    res = FSFILE_Read(file->handle, &read, file->pos, buf, left);
    if (R_FAILED(res) || read == 0)
    {
      break;
    }

    cur += read;
    file->pos += read;
    if (read == left)
    {
      break;
    }
    buf += read;
    left -= read;
  }

  *total = cur;
  return res;
}

Result IFile_Write(IFile *file, u64 *total, const void *buffer, u32 len, u32 flags)
{
  u32 written;
  u32 left;
  char *buf;
  u64 cur;
  Result res;

  if (len == 0)
  {
    *total = 0;
    return 0;
  }

  buf = (char *)buffer;
  cur = 0;
  left = len;
  while (1)
  {
    res = FSFILE_Write(file->handle, &written, file->pos, buf, left, flags);
    if (R_FAILED(res))
    {
      break;
    }

    cur += written;
    file->pos += written;
    if (written == left)
    {
      break;
    }
    buf += written;
    left -= written;
  }

  *total = cur;
  return res;
}

Result IFile_ReadAt(IFile *file, u64 *total, void *buffer, u32 offset, u32 len)
{
    *total = 0;
    file->pos = offset;
    return IFile_Read(file, total, buffer, len);
}

u32 IFile_Read2(IFile *file, void *buffer, u32 size, u32 offset)
{
    u64 total = 0;
    Result res = IFile_ReadAt(file, &total, buffer, offset, size);
    return R_SUCCEEDED(res) ? (u32)total : 0;
}
