/*  RetroArch - A frontend for libretro.
 *  Copyright (C) 2010-2013 - Hans-Kristian Arntzen
 *  Copyright (C) 2011-2013 - Daniel De Matteis
 *  Copyright (C) 2012-2013 - 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 <errno.h>
#include <unistd.h>
#include <string.h>
#include <sys/resource.h>

#include "frontend_android.h"
#include "../general.h"
#include "../performance.h"
#include "../driver.h"
#include "menu/rmenu.h"

#include "../config.def.h"
#include "frontend_context.h"

frontend_ctx_driver_t *frontend_ctx;

#if defined(ANDROID)
#define main_entry android_app_entry
#define returntype void*
#define signature() void* data
#define returnfunc() exit(0)
#define return_negative() return
#define return_var(var) return
#define declare_argc() int argc = 0
#define declare_argv() char *argv[1]
#define args_type() struct android_app*
#define args_initial_ptr() data
#elif defined(IOS) || defined(OSX) || defined(HAVE_BB10)
#define main_entry rarch_main
#define returntype int
#define signature() int argc, char *argv[]
#define returnfunc() return 0
#define return_negative() return 1
#define return_var(var) return var
#define declare_argc()
#define declare_argv()
#define args_type() void*
#define args_initial_ptr() NULL
#else
#define main_entry main
#define returntype int
#define signature() int argc, char *argv[]
#define returnfunc() return 0
#define return_negative() return 1
#define return_var(var) return var
#define declare_argc()
#define declare_argv()
#define args_type() void*
#define args_initial_ptr() NULL
#endif

#if defined(HAVE_BB10) || defined(ANDROID)
#define ra_preinited true
#else
#define ra_preinited false
#endif

#if defined(HAVE_BB10) || defined(RARCH_CONSOLE)
#define attempt_load_game false
#else
#define attempt_load_game true
#endif

#if defined(RARCH_CONSOLE) || defined(HAVE_BB10) || defined(ANDROID)
#define initial_menu_lifecycle_state (1ULL << MODE_LOAD_GAME)
#else
#define initial_menu_lifecycle_state (1ULL << MODE_GAME)
#endif

#if !defined(RARCH_CONSOLE) && !defined(HAVE_BB10) && !defined(ANDROID)
#define attempt_load_game_push_history false
#else
#define attempt_load_game_push_history true
#endif

#ifndef RARCH_CONSOLE
#define rarch_get_environment_console() (void)0
#endif

#if defined(RARCH_CONSOLE) || defined(__QNX__) || defined(ANDROID)
#define attempt_load_game_fails (1ULL << MODE_MENU)
#else
#define attempt_load_game_fails (1ULL << MODE_EXIT)
#endif

static void android_app_entry(void *data)
{
   declare_argc();
   declare_argv();
   args_type() args = (args_type())args_initial_ptr();
   unsigned i;
   frontend_ctx = (frontend_ctx_driver_t*)frontend_ctx_init_first();

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

   if (!ra_preinited)
   {
      rarch_main_clear_state();
      rarch_init_msg_queue();
   }

   if (frontend_ctx && frontend_ctx->environment_get)
   {
      frontend_ctx->environment_get(argc, argv, args);
      rarch_get_environment_console();
   }

   if (attempt_load_game)
   {
      int init_ret;
      if ((init_ret = rarch_main_init(argc, argv))) return_var(init_ret);
   }

#if defined(HAVE_MENU) || defined(HAVE_BB10)
   menu_init();

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

   g_extern.lifecycle_mode_state |= initial_menu_lifecycle_state;

   if (attempt_load_game_push_history)
   {
      // If we started a ROM directly from command line,
      // push it to ROM history.
      if (!g_extern.libretro_dummy)
         menu_rom_history_push_current();
   }

   for (;;)
   {
      if (g_extern.system.shutdown)
         break;
      else if (g_extern.lifecycle_mode_state & (1ULL << MODE_LOAD_GAME))
      {
         load_menu_game_prepare();

         // If ROM load fails, we exit RetroArch. On console it might make more sense to go back to menu though ...
         if (load_menu_game())
            g_extern.lifecycle_mode_state |= (1ULL << MODE_GAME);
         else
         {
            g_extern.lifecycle_mode_state = attempt_load_game_fails;

            if (g_extern.lifecycle_mode_state & (1ULL << MODE_EXIT))
            {
               if (frontend_ctx && frontend_ctx->shutdown)
                  frontend_ctx->shutdown(true);

               return_negative();
            }
         }

         g_extern.lifecycle_mode_state &= ~(1ULL << MODE_LOAD_GAME);
      }
      else if (g_extern.lifecycle_mode_state & (1ULL << MODE_GAME))
      {
         if (driver.video_poke->set_aspect_ratio)
            driver.video_poke->set_aspect_ratio(driver.video_data, g_settings.video.aspect_ratio_idx);

         while ((g_extern.is_paused && !g_extern.is_oneshot) ? rarch_main_idle_iterate() : rarch_main_iterate())
         {
            if (frontend_ctx && frontend_ctx->process_events)
               frontend_ctx->process_events(args);

            if (!(g_extern.lifecycle_mode_state & (1ULL << MODE_GAME)))
               break;
         }
         g_extern.lifecycle_mode_state &= ~(1ULL << MODE_GAME);
      }
      else if (g_extern.lifecycle_mode_state & (1ULL << MODE_MENU))
      {
         g_extern.lifecycle_mode_state |= 1ULL << MODE_MENU_PREINIT;
         // Menu should always run with vsync on.
         video_set_nonblock_state_func(false);
         // Stop all rumbling when entering RGUI.
         for (i = 0; i < MAX_PLAYERS; i++)
         {
            driver_set_rumble_state(i, RETRO_RUMBLE_STRONG, 0);
            driver_set_rumble_state(i, RETRO_RUMBLE_WEAK, 0);
         }

         // Override keyboard callback to redirect to menu instead.
         // We'll use this later for something ...
         // FIXME: This should probably be moved to menu_common somehow.
         retro_keyboard_event_t key_event = g_extern.system.key_event;
         g_extern.system.key_event = menu_key_event;

         if (driver.audio_data)
            audio_stop_func();

         while (!g_extern.system.shutdown && menu_iterate())
         {
            if (frontend_ctx && frontend_ctx->process_events)
               frontend_ctx->process_events(args);

            if (!(g_extern.lifecycle_mode_state & (1ULL << MODE_MENU)))
               break;
         }

         driver_set_nonblock_state(driver.nonblock_state);

         if (driver.audio_data && !g_extern.audio_data.mute && !audio_start_func())
         {
            RARCH_ERR("Failed to resume audio driver. Will continue without audio.\n");
            g_extern.audio_active = false;
         }

         g_extern.lifecycle_mode_state &= ~(1ULL << MODE_MENU);

         // Restore libretro keyboard callback.
         g_extern.system.key_event = key_event;
      }
      else
         break;
   }

   g_extern.system.shutdown = false;
   menu_free();

   if (g_extern.config_save_on_exit && *g_extern.config_path)
      config_save_file(g_extern.config_path);
#else
   while ((g_extern.is_paused && !g_extern.is_oneshot) ? rarch_main_idle_iterate() : rarch_main_iterate());
#endif

   rarch_main_deinit();
   rarch_deinit_msg_queue();
   global_uninit_drivers();

#ifdef PERF_TEST
   rarch_perf_log();
#endif

#if defined(HAVE_LOGGER) && !defined(ANDROID)
   logger_shutdown();
#elif defined(HAVE_FILE_LOGGER)
   if (g_extern.log_file)
      fclose(g_extern.log_file);
   g_extern.log_file = NULL;
#endif

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

   if (g_extern.lifecycle_mode_state & (1ULL << MODE_EXITSPAWN) && frontend_ctx
         && frontend_ctx->exitspawn)
      frontend_ctx->exitspawn();

   rarch_main_clear_state();

   if (frontend_ctx && frontend_ctx->shutdown)
      frontend_ctx->shutdown(false);

   returnfunc();
}

static inline void android_app_write_cmd (void *data, int8_t cmd)
{
   struct android_app *android_app = (struct android_app*)data;
   if (write(android_app->msgwrite, &cmd, sizeof(cmd)) != sizeof(cmd))
      RARCH_ERR("Failure writing android_app cmd: %s\n", strerror(errno));
}

static void android_app_set_input (void *data, AInputQueue* inputQueue)
{
   struct android_app *android_app = (struct android_app*)data;
   slock_lock(android_app->mutex);
   android_app->pendingInputQueue = inputQueue;
   android_app_write_cmd(android_app, APP_CMD_INPUT_CHANGED);
   while (android_app->inputQueue != android_app->pendingInputQueue)
      scond_wait(android_app->cond, android_app->mutex);
   slock_unlock(android_app->mutex);
}

static void android_app_set_window (void *data, ANativeWindow* window)
{
   struct android_app *android_app = (struct android_app*)data;
   slock_lock(android_app->mutex);
   if (android_app->pendingWindow != NULL)
      android_app_write_cmd(android_app, APP_CMD_TERM_WINDOW);

   android_app->pendingWindow = window;

   if (window != NULL)
      android_app_write_cmd(android_app, APP_CMD_INIT_WINDOW);

   while (android_app->window != android_app->pendingWindow)
      scond_wait(android_app->cond, android_app->mutex);

   slock_unlock(android_app->mutex);
}

static void android_app_set_activity_state (void *data, int8_t cmd)
{
   struct android_app *android_app = (struct android_app*)data;
   slock_lock(android_app->mutex);
   android_app_write_cmd(android_app, cmd);
   while (android_app->activityState != cmd && android_app->activityState != APP_CMD_DEAD)
      scond_wait(android_app->cond, android_app->mutex);
   slock_unlock(android_app->mutex);

   if (android_app->activityState == APP_CMD_DEAD)
      RARCH_LOG("RetroArch thread is dead.\n");
}

static void onDestroy(ANativeActivity* activity)
{
   RARCH_LOG("Destroy: %p\n", activity);
   struct android_app* android_app = (struct android_app*)activity->instance;

   sthread_join(android_app->thread);
   RARCH_LOG("Joined with RetroArch thread.\n");

   close(android_app->msgread);
   close(android_app->msgwrite);
   scond_free(android_app->cond);
   slock_free(android_app->mutex);
   free(android_app);
}

static void onStart(ANativeActivity* activity)
{
   RARCH_LOG("Start: %p\n", activity);
   android_app_set_activity_state((struct android_app*)activity->instance, APP_CMD_START);
}

static void onResume(ANativeActivity* activity)
{
   RARCH_LOG("Resume: %p\n", activity);
   android_app_set_activity_state((struct android_app*)activity->instance, APP_CMD_RESUME);
}

static void onPause(ANativeActivity* activity)
{
   RARCH_LOG("Pause: %p\n", activity);
   android_app_set_activity_state((struct android_app*)activity->instance, APP_CMD_PAUSE);
}

static void onStop(ANativeActivity* activity)
{
   RARCH_LOG("Stop: %p\n", activity);
   android_app_set_activity_state((struct android_app*)activity->instance, APP_CMD_STOP);
}

static void onConfigurationChanged (ANativeActivity *activity)
{
   struct android_app* android_app = (struct android_app*)activity->instance;
   RARCH_LOG("ConfigurationChanged: %p\n", activity);
   android_app_write_cmd(android_app, APP_CMD_CONFIG_CHANGED);
}

static void onWindowFocusChanged(ANativeActivity* activity, int focused)
{
   RARCH_LOG("WindowFocusChanged: %p -- %d\n", activity, focused);
   android_app_write_cmd((struct android_app*)activity->instance,
         focused ? APP_CMD_GAINED_FOCUS : APP_CMD_LOST_FOCUS);
}

static void onNativeWindowCreated(ANativeActivity* activity, ANativeWindow* window)
{
   RARCH_LOG("NativeWindowCreated: %p -- %p\n", activity, window);
   android_app_set_window((struct android_app*)activity->instance, window);
}

static void onNativeWindowDestroyed(ANativeActivity* activity, ANativeWindow* window)
{
   RARCH_LOG("NativeWindowDestroyed: %p -- %p\n", activity, window);
   android_app_set_window((struct android_app*)activity->instance, NULL);
}

static void onInputQueueCreated(ANativeActivity* activity, AInputQueue* queue)
{
   RARCH_LOG("InputQueueCreated: %p -- %p\n", activity, queue);
   android_app_set_input((struct android_app*)activity->instance, queue);
}

static void onInputQueueDestroyed(ANativeActivity* activity, AInputQueue* queue)
{
   RARCH_LOG("InputQueueDestroyed: %p -- %p\n", activity, queue);
   android_app_set_input((struct android_app*)activity->instance, NULL);
}

// --------------------------------------------------------------------
// Native activity interaction (called from main thread)
// --------------------------------------------------------------------

void ANativeActivity_onCreate(ANativeActivity* activity,
      void* savedState, size_t savedStateSize)
{
   (void)savedState;
   (void)savedStateSize;

   RARCH_LOG("Creating Native Activity: %p\n", activity);
   activity->callbacks->onDestroy = onDestroy;
   activity->callbacks->onStart = onStart;
   activity->callbacks->onResume = onResume;
   activity->callbacks->onSaveInstanceState = NULL;
   activity->callbacks->onPause = onPause;
   activity->callbacks->onStop = onStop;
   activity->callbacks->onConfigurationChanged = onConfigurationChanged;
   activity->callbacks->onLowMemory = NULL;
   activity->callbacks->onWindowFocusChanged = onWindowFocusChanged;
   activity->callbacks->onNativeWindowCreated = onNativeWindowCreated;
   activity->callbacks->onNativeWindowDestroyed = onNativeWindowDestroyed;
   activity->callbacks->onInputQueueCreated = onInputQueueCreated;
   activity->callbacks->onInputQueueDestroyed = onInputQueueDestroyed;

   // these are set only for the native activity, and are reset when it ends
   ANativeActivity_setWindowFlags(activity, AWINDOW_FLAG_KEEP_SCREEN_ON | AWINDOW_FLAG_FULLSCREEN, 0);

   struct android_app* android_app = (struct android_app*)malloc(sizeof(struct android_app));
   memset(android_app, 0, sizeof(struct android_app));
   android_app->activity = activity;

   android_app->mutex = slock_new();
   android_app->cond  = scond_new();

   int msgpipe[2];
   if (pipe(msgpipe))
   {
      RARCH_ERR("could not create pipe: %s.\n", strerror(errno));
      activity->instance = NULL;
   }
   android_app->msgread = msgpipe[0];
   android_app->msgwrite = msgpipe[1];

   android_app->thread = (sthread_t*)sthread_create(android_app_entry, android_app);

   // Wait for thread to start.
   slock_lock(android_app->mutex);
   while (!android_app->running)
      scond_wait(android_app->cond, android_app->mutex);
   slock_unlock(android_app->mutex);

   activity->instance = android_app;
}