/***************************************************************************
 *   SDCARD/MEMCARD File support
 *
 *
 ***************************************************************************/
#include "shared.h"
#include "font.h"
#include "saveicon.h"
#ifndef HW_RVL
#include "dvd.h"
#endif

#include <fat.h>
#include <sys/dir.h>

/* Support for MemCards  */
/**
 * libOGC System Work Area
 */
static u8 SysArea[CARD_WORKAREA] ATTRIBUTE_ALIGN (32);
static card_dir CardDir;
static card_file CardFile;
static card_stat CardStatus;

/**
 * DMA Transfer Area.
 * Must be 32-byte aligned.
 * 64k SRAM + 2k Icon
 */
static u8 savebuffer[0x26000] ATTRIBUTE_ALIGN (32);

int ManageSRAM (u8 direction, u8 device);
int ManageState (u8 direction, u8 device);

/****************************************************************************
 * FILE autoload (SRAM/FreezeState or Config File)
 *
 *
 *****************************************************************************/
void memfile_autoload()
{
	/* this should be transparent to the user */
  SILENT = 1; 

  /* SRAM */
  if (config.sram_auto != -1)
    ManageSRAM(1,config.sram_auto);

  /* STATE */
  if (config.freeze_auto != -1)
    ManageState(1,config.freeze_auto);

	SILENT = 0;
}

void memfile_autosave()
{
  int crccheck = crc32 (0, sram.sram, 0x10000);

  /* this should be transparent to the user */
  SILENT = 1;
  
  /* SRAM */
  if ((config.sram_auto != -1) && (crccheck != sram.crc))
    ManageSRAM(0, config.sram_auto);

  /* STATE */
  if (config.freeze_auto != -1)
    ManageState(0,config.freeze_auto);

  SILENT = 0;
  return;
}


/****************************************************************************
 * SDCARD Access functions
 *
 * We use the same buffer as for Memory Card manager
 * Function returns TRUE on success.
 *****************************************************************************/
static int SD_ManageFile(char *filename, int direction, int filetype)
{
  char pathname[MAXPATHLEN];
  int done = 0;
  int filesize;

  /* first check if directory exist */
  DIR_ITER *dir = diropen("/genplus/saves");
  if (dir == NULL) mkdir("/genplus/saves",S_IRWXU);
  else dirclose(dir);

  /* build complete SDCARD filename */
  sprintf (pathname, "/genplus/saves/%s", filename);

  /* open file */
  FILE *fp = fopen(pathname, direction ? "rb" : "wb");
  if (fp == NULL)
  {
    sprintf (filename, "Error opening %s", pathname);
    WaitPrompt(filename);
    return 0;
  }

	switch (direction)
	{
		case 0: /* SAVING */

			if (filetype) /* SRAM */
			{
				memcpy(savebuffer, sram.sram, 0x10000);
				sram.crc = crc32 (0, sram.sram, 0x10000);
        filesize = 0x10000;
			}
			else filesize = state_save(savebuffer); /* STATE */

      /* write buffer */
      done = fwrite(savebuffer, 1, filesize, fp);
      if (done < filesize)
      {
        sprintf (filename, "Error writing %s", pathname);
        WaitPrompt(filename);
        return 0;
      }

      fclose(fp);
      sprintf (filename, "Saved %d bytes successfully", done);
      WaitPrompt (filename);
      return 1;
		
		case 1: /* LOADING */
	
      /* read size */
      fseek(fp , 0 , SEEK_END);
      filesize = ftell (fp);
      fseek(fp, 0, SEEK_SET);

      /* read into buffer (32k blocks) */
      done = fread(savebuffer, 1, filesize, fp);
      if (done < filesize)
      {
        sprintf (filename, "Error reading %s", pathname);
        WaitPrompt(filename);
        return 0;
      }
      fclose(fp);

			if (filetype) /* SRAM */
			{
				memcpy(sram.sram, savebuffer, filesize);
				sram.crc = crc32 (0, sram.sram, 0x10000);
				system_reset ();
			}
			else state_load(savebuffer); /* STATE */
            
			sprintf (filename, "Loaded %d bytes successfully", done);
			WaitPrompt (filename);
			return 1;
	}
	
	return 0; 
}

/****************************************************************************
 * MountTheCard
 *
 * libOGC provides the CARD_Mount function, and it should be all you need.
 * However, experience with previous emulators has taught me that you are
 * better off doing a little bit more than that!
 *
 * Function returns TRUE on success.
 *****************************************************************************/
int MountTheCard (u8 slot)
{
	int tries = 0;
	int CardError;
	*(unsigned long *) (0xcc006800) |= 1 << 13; /*** Disable Encryption ***/
#ifndef HW_RVL
	uselessinquiry ();
#endif
  while (tries < 10)
  {
    VIDEO_WaitVSync ();
		CardError = CARD_Mount (slot, SysArea, NULL); /*** Don't need or want a callback ***/
		if (CardError == 0) return 1;
		else EXI_ProbeReset ();
		tries++;
	}
	return 0;
}

/****************************************************************************
 * CardFileExists
 *
 * Wrapper to search through the files on the card.
 * Returns TRUE if found.
 ****************************************************************************/
int CardFileExists (char *filename, u8 slot)
{
	int CardError = CARD_FindFirst (slot, &CardDir, TRUE);
	while (CardError != CARD_ERROR_NOFILE)
	{
		CardError = CARD_FindNext (&CardDir);
		if (strcmp ((char *) CardDir.filename, filename) == 0) return 1;
	}
	return 0;
}

/****************************************************************************
 * ManageSRAM
 *
 * Here is the main SRAM Management stuff.
 * The output file contains an icon (2K), 64 bytes comment and the SRAM (64k).
 * As memcards are allocated in blocks of 8k or more, you have a around
 * 6k bytes to save/load any other data you wish without altering any of the
 * main save / load code.
 *
 * direction == 0 save, 1 load.
 ****************************************************************************/
int ManageSRAM (u8 direction, u8 device)
{
	char filename[128];
	char action[80];
	int CardError;
	unsigned int SectorSize;
	int blocks;
	char comment[2][32] = { {"Genesis Plus 1.2a"}, {"SRAM Save"} };
  int outbytes = 0;
	int sbo;
	unsigned long inzipped,outzipped;

	if (!genromsize) return 0;

	/* clean buffer */
  memset(savebuffer, 0, 0x24000);

	if (direction) ShowAction ("Loading SRAM ...");
	else ShowAction ("Saving SRAM ...");

	/* First, build a filename */
	sprintf (filename, "MD-%04X.srm", realchecksum);
	strcpy (comment[1], filename);

	/* device is SDCARD, let's go */
	if (device == 0) return SD_ManageFile(filename,direction,1);
  
  /* set MCARD slot nr. */
  u8 CARDSLOT = device - 1;

	/* device is MCARD, we continue */
	if (direction == 0) /*** Saving ***/
	{
		/*** Build the output buffer ***/
		memcpy (&savebuffer, &icon, 2048);
		memcpy (&savebuffer[2048], &comment[0], 64);

		inzipped = 0x10000;
		outzipped = 0x12000;
		compress2 ((Bytef *) &savebuffer[2112+sizeof(outzipped)], &outzipped, (Bytef *) &sram.sram, inzipped, 9);
		memcpy(&savebuffer[2112], &outzipped, sizeof(outzipped));
	}
	
	outbytes = 2048 + 64 + outzipped + sizeof(outzipped);

	/*** Initialise the CARD system ***/
	memset (&SysArea, 0, CARD_WORKAREA);
	CARD_Init ("GENP", "00");

	/*** Attempt to mount the card ***/
	CardError = MountTheCard (CARDSLOT);

	if (CardError)
	{
		/*** Retrieve the sector size ***/
		CardError = CARD_GetSectorSize (CARDSLOT, &SectorSize);

		switch (direction)
		{
			case 0: /*** Saving ***/
				/*** Determine number of blocks on this card ***/
				blocks = (outbytes / SectorSize) * SectorSize;
				if (outbytes % SectorSize)  blocks += SectorSize;

				/*** Check if a previous save exists ***/
				if (CardFileExists (filename,CARDSLOT))
				{
					CardError = CARD_Open (CARDSLOT, filename, &CardFile);
					if (CardError)
					{
						sprintf (action, "Error Open : %d", CardError);
						WaitPrompt (action);
						CARD_Unmount (CARDSLOT);
						return 0;
					}

					int size = CardFile.len;
					CARD_Close (&CardFile);

					if (size < blocks)
					{
						/* new size is bigger: check if there is enough space left */
					  CardError = CARD_Create (CARDSLOT, "TEMP", blocks-size, &CardFile);
						if (CardError)
						{
							sprintf (action, "Error Update : %d", CardError);
							WaitPrompt (action);
							CARD_Unmount (CARDSLOT);
							return 0;
						}
						CARD_Close (&CardFile);
						CARD_Delete(CARDSLOT, "TEMP");
					}

					/* always delete existing slot */
					CARD_Delete(CARDSLOT, filename);
				}                    
				
				/*** Create a new slot ***/
				CardError = CARD_Create (CARDSLOT, filename, blocks, &CardFile);
				if (CardError)
				{
					sprintf (action, "Error create : %d %d", CardError, CARDSLOT);
					WaitPrompt (action);
					CARD_Unmount (CARDSLOT);
					return 0;
				}

				/*** Continue and save ***/
				CARD_GetStatus (CARDSLOT, CardFile.filenum, &CardStatus);
				CardStatus.icon_addr = 0x0;
				CardStatus.icon_fmt = 2;
				CardStatus.icon_speed = 1;
				CardStatus.comment_addr = 2048;
				CARD_SetStatus (CARDSLOT, CardFile.filenum, &CardStatus);

				/*** And write the blocks out ***/
				sbo = 0;
				while (outbytes > 0)
				{
					CardError = CARD_Write (&CardFile, &savebuffer[sbo], SectorSize, sbo);
					outbytes -= SectorSize;
					sbo += SectorSize;
				}

				CARD_Close (&CardFile);
				CARD_Unmount (CARDSLOT);
				sram.crc = crc32 (0, &sram.sram[0], 0x10000);
				sprintf (action, "Saved %d bytes successfully", blocks);
				WaitPrompt (action);
				return 1;

			default: /*** Loading ***/
				if (!CardFileExists (filename,CARDSLOT))
				{
					WaitPrompt ("No SRAM File Found");
					CARD_Unmount (CARDSLOT);
					return 0;
				}

				memset (&CardFile, 0, sizeof (CardFile));
				CardError = CARD_Open (CARDSLOT, filename, &CardFile);
				if (CardError)
				{
					sprintf (action, "Error Open : %d", CardError);
					WaitPrompt (action);
					CARD_Unmount (CARDSLOT);
					return 0;
				}

				blocks = CardFile.len;
				if (blocks < SectorSize) blocks = SectorSize;
				if (blocks % SectorSize) blocks++;

				/*** Just read the file back in ***/
				sbo = 0;
				int size = blocks;
				while (blocks > 0)
				{
					CARD_Read (&CardFile, &savebuffer[sbo], SectorSize, sbo);
					sbo += SectorSize;
					blocks -= SectorSize;
				}
				CARD_Close (&CardFile);
				CARD_Unmount (CARDSLOT);

				/* Copy to SRAM */
				memcpy(&inzipped,&savebuffer[2112],sizeof(inzipped));
				outzipped = 0x10000;
				uncompress ((Bytef *) &sram.sram, &outzipped, (Bytef *) &savebuffer[2112+sizeof(inzipped)], inzipped);
				sram.crc = crc32 (0, &sram.sram[0], 0x10000);
				system_reset ();

				/*** Inform user ***/
				sprintf (action, "Loaded %d bytes successfully", size);
				WaitPrompt (action);
				return 1;
		}
	}
	else WaitPrompt ("Unable to mount memory card");
	return 0; /*** Signal failure ***/
}

/****************************************************************************
 * ManageState
 *
 * Here is the main Freeze File Management stuff.
 * The output file contains an icon (2K), 64 bytes comment and the STATE (~128k)
 *
 * direction == 0 save, 1 load.
 ****************************************************************************/
int ManageState (u8 direction, u8 device)
{
	char filename[128];
	char action[80];
	int CardError;
	unsigned int SectorSize;
	int blocks;
	char comment[2][32] = { {"Genesis Plus 1.2a [FRZ]"}, {"Freeze State"} };
	int outbytes = 0;
	int sbo;
	int state_size = 0;

	if (!genromsize) return 0;

	/* clean buffer */
	memset(savebuffer, 0, 0x24000);

  if (direction) ShowAction ("Loading State ...");
	else ShowAction ("Saving State ...");

	/* First, build a filename */
	sprintf (filename, "MD-%04X.gpz", realchecksum);
	strcpy (comment[1], filename);

	/* device is SDCARD, let's go */
	if (device == 0) return SD_ManageFile(filename,direction,0);
  
  /* set MCARD slot nr. */
  u8 CARDSLOT = device - 1;

	/* device is MCARD, we continue */
	if (direction == 0) /* Saving */
	{
		/* Build the output buffer */
		memcpy (&savebuffer, &icon, 2048);
		memcpy (&savebuffer[2048], &comment[0], 64);
		state_size = state_save(&savebuffer[2112]);
	}

	outbytes = 2048 + 64 + state_size;

	/*** Initialise the CARD system ***/
	memset (&SysArea, 0, CARD_WORKAREA);
	CARD_Init ("GENP", "00");

	/*** Attempt to mount the card ***/
	CardError = MountTheCard (CARDSLOT);

	if (CardError)
	{
		/*** Retrieve the sector size ***/
		CardError = CARD_GetSectorSize (CARDSLOT, &SectorSize);

		switch (direction)
		{
			case 0: /*** Saving ***/
				/*** Determine number of blocks on this card ***/
				blocks = (outbytes / SectorSize) * SectorSize;
				if (outbytes % SectorSize) blocks += SectorSize;

				/*** Check if a previous save exists ***/
				if (CardFileExists (filename, CARDSLOT))
				{
					CardError = CARD_Open (CARDSLOT, filename, &CardFile);
					if (CardError)
					{
						sprintf (action, "Error Open : %d", CardError);
						WaitPrompt (action);
						CARD_Unmount (CARDSLOT);
						return 0;
					}

					int size = CardFile.len;
					CARD_Close (&CardFile);

					if (size < blocks)
					{
						/* new size is bigger: check if there is enough space left */
					  CardError = CARD_Create (CARDSLOT, "TEMP", blocks-size, &CardFile);
						if (CardError)
						{
							sprintf (action, "Error Update : %d", CardError);
							WaitPrompt (action);
							CARD_Unmount (CARDSLOT);
							return 0;
						}
						CARD_Close (&CardFile);
						CARD_Delete(CARDSLOT, "TEMP");
					}

					/* always delete existing slot */
					CARD_Delete(CARDSLOT, filename);
				}                    

				/*** Create a new slot ***/
				CardError = CARD_Create (CARDSLOT, filename, blocks, &CardFile);
				if (CardError)
				{
					sprintf (action, "Error create : %d %d", CardError, CARDSLOT);
					WaitPrompt (action);
					CARD_Unmount (CARDSLOT);
					return 0;
				}
				
				/*** Continue and save ***/
				CARD_GetStatus (CARDSLOT, CardFile.filenum, &CardStatus);
				CardStatus.icon_addr = 0x0;
				CardStatus.icon_fmt = 2;
				CardStatus.icon_speed = 1;
				CardStatus.comment_addr = 2048;
				CARD_SetStatus (CARDSLOT, CardFile.filenum, &CardStatus);

				/*** And write the blocks out ***/
				sbo = 0;
				while (outbytes > 0)
				{
					CardError = CARD_Write (&CardFile, &savebuffer[sbo], SectorSize, sbo);
					outbytes -= SectorSize;
					sbo += SectorSize;
				}

				CARD_Close (&CardFile);
				CARD_Unmount (CARDSLOT);
				sprintf (action, "Saved %d bytes successfully", blocks);
				WaitPrompt (action);
				return 1;

			default: /*** Loading ***/
				if (!CardFileExists (filename, CARDSLOT))
				{
					WaitPrompt ("No Savestate Found");
					CARD_Unmount (CARDSLOT);
					return 0;
				}

				memset (&CardFile, 0, sizeof (CardFile));
				CardError = CARD_Open (CARDSLOT, filename, &CardFile);
				if (CardError)
				{
					sprintf (action, "Error Open : %d", CardError);
					WaitPrompt (action);
					CARD_Unmount (CARDSLOT);
					return 0;
				}

				blocks = CardFile.len;
				if (blocks < SectorSize) blocks = SectorSize;
				if (blocks % SectorSize) blocks++;

				/*** Just read the file back in ***/
				sbo = 0;
				int size = blocks;
				while (blocks > 0)
				{
					CARD_Read (&CardFile, &savebuffer[sbo], SectorSize, sbo);
					sbo += SectorSize;
					blocks -= SectorSize;
				}
				CARD_Close (&CardFile);
				CARD_Unmount (CARDSLOT);

				/*** Load State ***/
			    state_load(&savebuffer[2112]);

				/*** Inform user ***/
				sprintf (action, "Loaded %d bytes successfully", size);
				WaitPrompt (action);
				return 1;
		}
	}
	else WaitPrompt ("Unable to mount memory card");
	return 0; /*** Signal failure ***/
}