/* RetroArch - A frontend for libretro.
 * Copyright (C) 2010-2014 - Hans-Kristian Arntzen
 * Copyright (C) 2011-2015 - Daniel De Matteis
 *
 * 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 <stdint.h>
#include <boolean.h>
#include <stddef.h>
#include <string.h>

#include <file/config_file.h>
#include "../general.h"
#include "../file_ext.h"
#include <file/file_path.h>
#include <file/dir_list.h>
#include "frontend_driver.h"

struct defaults g_defaults;

/*We need to set libretro to the first entry in the cores
 * directory so that it will be saved to the config file
 */
static void find_first_libretro_core(char *first_file,
   size_t size_of_first_file, const char *dir,
   const char * ext)
{
   struct string_list *list;
   size_t i;
   bool ret = false;

   RARCH_LOG("Searching for valid libretro implementation in: \"%s\".\n",
         dir);

   list = (struct string_list*)dir_list_new(dir, ext, false);
   if (!list)
   {
      RARCH_ERR("Couldn't read directory. Cannot infer default libretro core.\n");
      return;
   }
   
   for (i = 0; i < list->size && !ret; i++)
   {
      char fname[PATH_MAX_LENGTH];
      const char *libretro_elem = (const char*)list->elems[i].data;

      RARCH_LOG("Checking library: \"%s\".\n", libretro_elem);

      if (!libretro_elem)
         continue;

      fill_pathname_base(fname, libretro_elem, sizeof(fname));

      if (strncmp(fname, SALAMANDER_FILE, sizeof(fname)) == 0)
      {
         if ((i + 1) == list->size)
         {
            RARCH_WARN("Entry is RetroArch Salamander itself, but is last entry. No choice but to set it.\n");
            strlcpy(first_file, fname, size_of_first_file);
         }

         continue;
      }

      strlcpy(first_file, fname, size_of_first_file);
      RARCH_LOG("First found libretro core is: \"%s\".\n", first_file);
      ret = true;
   }

   dir_list_free(list);
}

static void find_and_set_first_file(char *path, size_t sizeof_path,
      const char *ext)
{
   /* Last fallback - we'll need to start the first executable file 
    * we can find in the RetroArch cores directory.
    */

   char first_file[PATH_MAX_LENGTH] = {0};
   find_first_libretro_core(first_file, sizeof(first_file),
         g_defaults.core_dir, ext);

   if (first_file[0] != '\0')
   {
      fill_pathname_join(path, g_defaults.core_dir, first_file, sizeof_path);
      RARCH_LOG("libretro_path now set to: %s.\n", path);
   }
   else
      RARCH_ERR("Failed last fallback - RetroArch Salamander will exit.\n");
}

static void salamander_init(char *libretro_path, size_t sizeof_libretro_path)
{
   /* normal executable loading path */
   bool config_file_exists = false;

   if (path_file_exists(g_defaults.config_path))
      config_file_exists = true;

   if (config_file_exists)
   {
      char tmp_str[PATH_MAX_LENGTH];
      config_file_t * conf = (config_file_t*)config_file_new(g_defaults.config_path);

      if (conf)
      {
         config_get_array(conf, "libretro_path", tmp_str, sizeof(tmp_str));
         config_file_free(conf);
         strlcpy(libretro_path, tmp_str, sizeof_libretro_path);
      }
#ifdef GEKKO
      else /* stupid libfat bug or something; sometimes it says the file is there when it doesn't */
         config_file_exists = false;
#endif
   }

   if (!config_file_exists || !strcmp(libretro_path, ""))
      find_and_set_first_file(libretro_path, sizeof_libretro_path, EXT_EXECUTABLES);
   else
      RARCH_LOG("Start [%s] found in retroarch.cfg.\n", libretro_path);

   if (!config_file_exists)
   {
      config_file_t *conf = (config_file_t*)config_file_new(NULL);

      if (conf)
      {
         config_set_string(conf, "libretro_path", libretro_path);
         config_file_write(conf, g_defaults.config_path);
         config_file_free(conf);
      }
   }
}

int main(int argc, char *argv[])
{
   char libretro_path[PATH_MAX_LENGTH];
   void *args = NULL;
   struct rarch_main_wrap *wrap_args = NULL;
   frontend_ctx_driver_t *frontend_ctx = NULL;

   frontend_ctx = (frontend_ctx_driver_t*)frontend_ctx_init_first();

   if (!frontend_ctx)
      return 0;

   if (frontend_ctx && frontend_ctx->init)
      frontend_ctx->init(args);

   if (frontend_ctx && frontend_ctx->environment_get)
      frontend_ctx->environment_get(&argc, argv, args, wrap_args);

   salamander_init(libretro_path, sizeof(libretro_path));

   if (frontend_ctx && frontend_ctx->deinit)
      frontend_ctx->deinit(args);

   if (frontend_ctx && frontend_ctx->exitspawn)
      frontend_ctx->exitspawn(libretro_path, sizeof(libretro_path));

   return 1;
}
