/* RetroArch - A frontend for libretro.
 * Copyright (C) 2010-2014 - Hans-Kristian Arntzen
 * Copyright (C) 2011-2015 - Daniel De Matteis
 * Copyright (C) 2012-2015 - Michael Lelli
 *
 * RetroArch is free software: you can redistribute it and/or modify it under the terms
 * of the GNU General Public License as published by the Free Software Found-
 * ation, either version 3 of the License, or (at your option) any later version.
 *
 * RetroArch 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 General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License along with RetroArch.
 * If not, see <http://www.gnu.org/licenses/>.
 */

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <fat.h>
#include <gctypes.h>
#include <ogc/cache.h>
#include "../../gfx/drivers/ppc_asm.h"
#include <file/file_path.h>
#include <retro_miscellaneous.h>
#include <ogc/system.h>
#include <ogc/usbstorage.h>
#include <sdcard/wiisd_io.h>

#define EXECUTE_ADDR ((uint8_t *) 0x91800000)
#define BOOTER_ADDR ((uint8_t *) 0x93000000)
#define ARGS_ADDR ((uint8_t *) 0x93200000)

extern uint8_t _binary_wii_app_booter_app_booter_bin_start[];
extern uint8_t _binary_wii_app_booter_app_booter_bin_end[];
#define booter_start _binary_wii_app_booter_app_booter_bin_start
#define booter_end _binary_wii_app_booter_app_booter_bin_end

#include "../../retroarch_logger.h"

#ifdef IS_SALAMANDER
char gx_rom_path[PATH_MAX_LENGTH];
#endif

static void dol_copy_argv_path(const char *dolpath, const char *argpath)
{
   char tmp[PATH_MAX_LENGTH];
   size_t len, t_len;
   struct __argv *argv = (struct __argv *) ARGS_ADDR;
   memset(ARGS_ADDR, 0, sizeof(struct __argv));
   char *cmdline = (char *) ARGS_ADDR + sizeof(struct __argv);
   argv->argvMagic = ARGV_MAGIC;
   argv->commandLine = cmdline;
   len = 0;

   // a device-less fullpath
   if (dolpath[0] == '/')
   {
      char *dev = strchr(__system_argv->argv[0], ':');
      t_len = dev - __system_argv->argv[0] + 1;
      memcpy(cmdline, __system_argv->argv[0], t_len);
      len += t_len;
   }
   // a relative path
   else if (strstr(dolpath, "sd:/") != dolpath && strstr(dolpath, "usb:/") != dolpath &&
       strstr(dolpath, "carda:/") != dolpath && strstr(dolpath, "cardb:/") != dolpath)
   {
      fill_pathname_parent_dir(tmp, __system_argv->argv[0], sizeof(tmp));
      t_len = strlen(tmp);
      memcpy(cmdline, tmp, t_len);
      len += t_len;
   }

   t_len = strlen(dolpath);
   memcpy(cmdline + len, dolpath, t_len);
   len += t_len;
   cmdline[len++] = 0;

   // file must be split into two parts, the path and the actual filename
   // done to be compatible with loaders
   if (argpath && strrchr(argpath, '/') != NULL)
   {
      // basedir
      fill_pathname_parent_dir(tmp, argpath, sizeof(tmp));
      t_len = strlen(tmp);
      memcpy(cmdline + len, tmp, t_len);
      len += t_len;
      cmdline[len++] = 0;

      // filename
      char *name = strrchr(argpath, '/') + 1;
      t_len = strlen(name);
      memcpy(cmdline + len, name, t_len);
      len += t_len;
      cmdline[len++] = 0;
   }

   cmdline[len++] = 0;
   argv->length = len;
   DCFlushRange(ARGS_ADDR, sizeof(struct __argv) + argv->length);
}

// WARNING: after we move any data into EXECUTE_ADDR, we can no longer use any
// heap memory and are restricted to the stack only
void system_exec_wii(const char *_path, bool should_load_game)
{
#ifndef IS_SALAMANDER
   bool original_verbose = g_extern.verbosity;
   g_extern.verbosity = true;
#endif

   char path[PATH_MAX_LENGTH];
   char game_path[PATH_MAX_LENGTH];

   // copy heap info into stack so it survives us moving the .dol into MEM2
   strlcpy(path, _path, sizeof(path));
   if (should_load_game)
   {
#ifdef IS_SALAMANDER
      strlcpy(game_path, gx_rom_path, sizeof(game_path));
#else
      strlcpy(game_path, g_extern.fullpath, sizeof(game_path));
#endif
   }

   RARCH_LOG("Attempt to load executable: [%s]\n", path);

   FILE * fp = fopen(path, "rb");
   if (fp == NULL)
   {
      RARCH_ERR("Could not open DOL file %s.\n", path);
      goto exit;
   }

   fseek(fp, 0, SEEK_END);
   size_t size = ftell(fp);
   fseek(fp, 0, SEEK_SET);

   // try to allocate a buffer for it. if we can't, fail
   void *dol = malloc(size);
   if (!dol)
   {
      RARCH_ERR("Could not execute DOL file %s.\n", path);
      fclose(fp);
      goto exit;
   }

   fread(dol, 1, size, fp);
   fclose(fp);

   fatUnmount("carda:");
   fatUnmount("cardb:");
   fatUnmount("sd:");
   fatUnmount("usb:");
   __io_wiisd.shutdown();
   __io_usbstorage.shutdown();

   // don't use memcpy, there might be an overlap
   memmove(EXECUTE_ADDR, dol, size);
   DCFlushRange(EXECUTE_ADDR, size);

   dol_copy_argv_path(path, should_load_game ? game_path : NULL);

   size_t booter_size = booter_end - booter_start;
   memcpy(BOOTER_ADDR, booter_start, booter_size);
   DCFlushRange(BOOTER_ADDR, booter_size);

   RARCH_LOG("jumping to %08x\n", (unsigned) BOOTER_ADDR);
   SYS_ResetSystem(SYS_SHUTDOWN,0,0);
   __lwp_thread_stopmultitasking((void (*)(void)) BOOTER_ADDR);

exit:
   (void)0;
#ifndef IS_SALAMANDER
   g_extern.verbosity = original_verbose;
#endif
}
