/*  RetroArch - A frontend for libretro.
 *  Copyright (C) 2010-2013 - Hans-Kristian Arntzen
 *  Copyright (C) 2011-2013 - 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 <android/keycodes.h>
#include <unistd.h>
#include <dlfcn.h>
#include "input_autodetect.h"
#include "../../../frontend/frontend_android.h"
#include "../../../input/input_common.h"
#include "../../../performance.h"
#include "../../../general.h"
#include "../../../driver.h"

#define MAX_TOUCH 16

#define PRESSED_UP(x, y)    ((y <= dzone_min))
#define PRESSED_DOWN(x, y)  ((y >= dzone_max))
#define PRESSED_LEFT(x, y)  ((x <= dzone_min))
#define PRESSED_RIGHT(x, y) ((x >= dzone_max))

static unsigned pads_connected;
static int state_device_ids[MAX_PADS];
static uint64_t state[MAX_PADS];
uint64_t keycode_lut[LAST_KEYCODE];
dpad_values_t dpad_state[MAX_PADS]; 

struct input_pointer
{
   int16_t x, y;
   int16_t full_x, full_y;
};

static struct input_pointer pointer[MAX_TOUCH];
static unsigned pointer_count;

enum
{
   AXIS_X = 0,
   AXIS_Y = 1,
   AXIS_Z = 11,
   AXIS_RZ = 14
};

void (*engine_handle_dpad)(AInputEvent*, size_t, int, char*, size_t, int, bool);

extern float AMotionEvent_getAxisValue(const AInputEvent* motion_event,
      int32_t axis, size_t pointer_index);

static typeof(AMotionEvent_getAxisValue) *p_AMotionEvent_getAxisValue;

#define AMotionEvent_getAxisValue (*p_AMotionEvent_getAxisValue)

float getAxis(AInputEvent *event, int stick, int axis, int pointer)
{
   int axis_arg[2][2] = {{AXIS_X, AXIS_Y}, {AXIS_Z, AXIS_RZ}};
   return AMotionEvent_getAxisValue(event, axis_arg[stick][axis], pointer);
}

/**
 * Process the next main command.
 */
void engine_handle_cmd(void)
{
   struct android_app *android_app = (struct android_app*)g_android;
   int8_t cmd;

   if (read(android_app->msgread, &cmd, sizeof(cmd)) != sizeof(cmd))
      cmd = -1;

   switch (cmd)
   {
      case APP_CMD_INPUT_CHANGED:
         pthread_mutex_lock(&android_app->mutex);

         if (android_app->inputQueue != NULL)
            AInputQueue_detachLooper(android_app->inputQueue);

         android_app->inputQueue = android_app->pendingInputQueue;

         if (android_app->inputQueue != NULL)
         {
            RARCH_LOG("Attaching input queue to looper");
            AInputQueue_attachLooper(android_app->inputQueue,
                  android_app->looper, LOOPER_ID_INPUT, NULL,
                  NULL);
         }

         pthread_cond_broadcast(&android_app->cond);
         pthread_mutex_unlock(&android_app->mutex);
         
         break;

      case APP_CMD_INIT_WINDOW:
         pthread_mutex_lock(&android_app->mutex);
         android_app->window = android_app->pendingWindow;
         pthread_cond_broadcast(&android_app->cond);
         pthread_mutex_unlock(&android_app->mutex);

         if (g_extern.lifecycle_state & (1ULL << RARCH_PAUSE_TOGGLE))
            init_drivers();
         break;

      case APP_CMD_RESUME:
         pthread_mutex_lock(&android_app->mutex);
         android_app->activityState = cmd;
         pthread_cond_broadcast(&android_app->cond);
         pthread_mutex_unlock(&android_app->mutex);
         break;

      case APP_CMD_START:
         pthread_mutex_lock(&android_app->mutex);
         android_app->activityState = cmd;
         pthread_cond_broadcast(&android_app->cond);
         pthread_mutex_unlock(&android_app->mutex);
         break;

      case APP_CMD_PAUSE:
         pthread_mutex_lock(&android_app->mutex);
         android_app->activityState = cmd;
         pthread_cond_broadcast(&android_app->cond);
         pthread_mutex_unlock(&android_app->mutex);

         if (!(g_extern.lifecycle_state & (1ULL << RARCH_QUIT_KEY)))
         {
            RARCH_LOG("Pausing RetroArch.\n");
            g_extern.lifecycle_state |= (1ULL << RARCH_PAUSE_TOGGLE);
         }
         break;

      case APP_CMD_STOP:
         pthread_mutex_lock(&android_app->mutex);
         android_app->activityState = cmd;
         pthread_cond_broadcast(&android_app->cond);
         pthread_mutex_unlock(&android_app->mutex);
         break;

      case APP_CMD_CONFIG_CHANGED:
         break;
      case APP_CMD_TERM_WINDOW:
         pthread_mutex_lock(&android_app->mutex);

         /* The window is being hidden or closed, clean it up. */
         /* terminate display/EGL context here */
         if (g_extern.lifecycle_state & (1ULL << RARCH_PAUSE_TOGGLE))
            uninit_drivers();
         else
            RARCH_WARN("Window is terminated outside PAUSED state.\n");

         android_app->window = NULL;
         pthread_cond_broadcast(&android_app->cond);
         pthread_mutex_unlock(&android_app->mutex);
         break;

      case APP_CMD_GAINED_FOCUS:
         g_extern.lifecycle_state &= ~(1ULL << RARCH_PAUSE_TOGGLE);
         break;

      case APP_CMD_LOST_FOCUS:
         break;

      case APP_CMD_DESTROY:
         g_extern.lifecycle_state |= (1ULL << RARCH_QUIT_KEY);
         break;
   }
}

static void engine_handle_dpad_default(AInputEvent *event,
      size_t motion_pointer, int state_id, char *msg, size_t msg_sizeof,
      int source, bool debug_enable)
{
   uint64_t *state_cur = &state[state_id];
   float dzone_min = dpad_state[state_id].dzone_min;
   float dzone_max = dpad_state[state_id].dzone_max;
   float x = AMotionEvent_getX(event, motion_pointer);
   float y = AMotionEvent_getY(event, motion_pointer);

   *state_cur &= ~((1ULL << RETRO_DEVICE_ID_JOYPAD_LEFT) | 
         (1ULL << RETRO_DEVICE_ID_JOYPAD_RIGHT) | (1ULL << RETRO_DEVICE_ID_JOYPAD_UP) |
         (1ULL << RETRO_DEVICE_ID_JOYPAD_DOWN));
   *state_cur |= PRESSED_LEFT(x, y)  ? (1ULL << RETRO_DEVICE_ID_JOYPAD_LEFT)  : 0;
   *state_cur |= PRESSED_RIGHT(x, y) ? (1ULL << RETRO_DEVICE_ID_JOYPAD_RIGHT) : 0;
   *state_cur |= PRESSED_UP(x, y)    ? (1ULL << RETRO_DEVICE_ID_JOYPAD_UP)    : 0;
   *state_cur |= PRESSED_DOWN(x, y)  ? (1ULL << RETRO_DEVICE_ID_JOYPAD_DOWN)  : 0;

   if (debug_enable)
      snprintf(msg, msg_sizeof, "Pad %d : x = %.2f, y = %.2f, src %d.\n",
            state_id, x, y, source);
}

static void engine_handle_dpad_getaxisvalue(AInputEvent *event,
      size_t motion_pointer, int state_id, char *msg, size_t msg_sizeof, int source,
      bool debug_enable)
{
   uint64_t *state_cur = &state[state_id];
   float dzone_min = dpad_state[state_id].dzone_min;
   float dzone_max = dpad_state[state_id].dzone_max;
   float x = AMotionEvent_getAxisValue(event, AXIS_X, motion_pointer);
   float y = AMotionEvent_getAxisValue(event, AXIS_Y, motion_pointer);
   float z = AMotionEvent_getAxisValue(event, AXIS_Z, motion_pointer);
   float rz = AMotionEvent_getAxisValue(event, AXIS_RZ, motion_pointer);

   *state_cur &= ~((1ULL << RETRO_DEVICE_ID_JOYPAD_LEFT) | 
         (1ULL << RETRO_DEVICE_ID_JOYPAD_RIGHT) | (1ULL << RETRO_DEVICE_ID_JOYPAD_UP) |
         (1ULL << RETRO_DEVICE_ID_JOYPAD_DOWN));
   *state_cur |= PRESSED_LEFT(x, y)  ? (1ULL << RETRO_DEVICE_ID_JOYPAD_LEFT)  : 0;
   *state_cur |= PRESSED_RIGHT(x, y) ? (1ULL << RETRO_DEVICE_ID_JOYPAD_RIGHT) : 0;
   *state_cur |= PRESSED_UP(x, y)    ? (1ULL << RETRO_DEVICE_ID_JOYPAD_UP)    : 0;
   *state_cur |= PRESSED_DOWN(x, y)  ? (1ULL << RETRO_DEVICE_ID_JOYPAD_DOWN)  : 0;

   if (debug_enable)
      snprintf(msg, msg_sizeof, "Pad %d : x %.2f, y %.2f, z %.2f, rz %.2f, src %d.\n", 
            state_id, x, y, z, rz, source);
}

static void *android_input_init(void)
{
   unsigned i, j;
   pads_connected = 0;

   input_autodetect_init();

   for(i = 0; i < MAX_PADS; i++)
   {
      for(j = 0; j < RARCH_FIRST_META_KEY; j++)
      {
         g_settings.input.binds[i][j].id = i;
         g_settings.input.binds[i][j].joykey = 0;
      }

      g_settings.input.binds[i][RETRO_DEVICE_ID_JOYPAD_B].joykey = (1ULL << RETRO_DEVICE_ID_JOYPAD_B);
      g_settings.input.binds[i][RETRO_DEVICE_ID_JOYPAD_Y].joykey = (1ULL << RETRO_DEVICE_ID_JOYPAD_Y);
      g_settings.input.binds[i][RETRO_DEVICE_ID_JOYPAD_SELECT].joykey = (1ULL << RETRO_DEVICE_ID_JOYPAD_SELECT);
      g_settings.input.binds[i][RETRO_DEVICE_ID_JOYPAD_START].joykey = (1ULL << RETRO_DEVICE_ID_JOYPAD_START);
      g_settings.input.binds[i][RETRO_DEVICE_ID_JOYPAD_UP].joykey = (1ULL << RETRO_DEVICE_ID_JOYPAD_UP);
      g_settings.input.binds[i][RETRO_DEVICE_ID_JOYPAD_DOWN].joykey = (1ULL << RETRO_DEVICE_ID_JOYPAD_DOWN);
      g_settings.input.binds[i][RETRO_DEVICE_ID_JOYPAD_LEFT].joykey = (1ULL << RETRO_DEVICE_ID_JOYPAD_LEFT);
      g_settings.input.binds[i][RETRO_DEVICE_ID_JOYPAD_RIGHT].joykey = (1ULL << RETRO_DEVICE_ID_JOYPAD_RIGHT);
      g_settings.input.binds[i][RETRO_DEVICE_ID_JOYPAD_A].joykey = (1ULL << RETRO_DEVICE_ID_JOYPAD_A);
      g_settings.input.binds[i][RETRO_DEVICE_ID_JOYPAD_X].joykey = (1ULL << RETRO_DEVICE_ID_JOYPAD_X);
      g_settings.input.binds[i][RETRO_DEVICE_ID_JOYPAD_L].joykey = (1ULL << RETRO_DEVICE_ID_JOYPAD_L);
      g_settings.input.binds[i][RETRO_DEVICE_ID_JOYPAD_R].joykey = (1ULL << RETRO_DEVICE_ID_JOYPAD_R);
      g_settings.input.binds[i][RETRO_DEVICE_ID_JOYPAD_L2].joykey = (1ULL << RETRO_DEVICE_ID_JOYPAD_L2);
      g_settings.input.binds[i][RETRO_DEVICE_ID_JOYPAD_R2].joykey = (1ULL << RETRO_DEVICE_ID_JOYPAD_R2);
      g_settings.input.binds[i][RETRO_DEVICE_ID_JOYPAD_L3].joykey = (1ULL << RETRO_DEVICE_ID_JOYPAD_L3);
      g_settings.input.binds[i][RETRO_DEVICE_ID_JOYPAD_R3].joykey = (1ULL << RETRO_DEVICE_ID_JOYPAD_R3);

      dpad_state[i].dzone_min = -0.99f;
      dpad_state[i].dzone_max = 0.99f;
      g_settings.input.dpad_emulation[i] = DPAD_EMULATION_LSTICK;
   }

   if ((dlopen("/system/lib/libandroid.so", RTLD_LOCAL | RTLD_LAZY)) == 0)
   {
      RARCH_WARN("Unable to open libandroid.so\n");
      return (void*)-1;
   }
   else
   {
      p_AMotionEvent_getAxisValue = dlsym(RTLD_DEFAULT, "AMotionEvent_getAxisValue");

      if (p_AMotionEvent_getAxisValue != NULL)
      {
         RARCH_LOG("Setting engine_handle_dpad to 'Get Axis Value' (for reading extra analog sticks)");
         engine_handle_dpad = engine_handle_dpad_getaxisvalue;
      }
      else
      {
         RARCH_LOG("Setting engine_handle_dpad to 'Default'");
         engine_handle_dpad = engine_handle_dpad_default;
      }
   }

   return (void*)-1;
}

// Handle all events. If our activity is in pause state, block until we're unpaused.

static void android_input_poll(void *data)
{
   int ident;
   while ((ident = ALooper_pollAll((input_key_pressed_func(RARCH_PAUSE_TOGGLE)) ? -1 : 0,
               NULL, NULL, NULL)) >= 0)
   {
      if (ident == LOOPER_ID_INPUT)
      {
         bool debug_enable = g_settings.input.debug_enable;
         struct android_app *android_app = (struct android_app*)g_android;
         uint64_t *lifecycle_state = &g_extern.lifecycle_state;
         AInputEvent* event = NULL;

         *lifecycle_state &= ~((1ULL << RARCH_RESET) | (1ULL << RARCH_REWIND) | (1ULL << RARCH_FAST_FORWARD_KEY) | (1ULL << RARCH_FAST_FORWARD_HOLD_KEY) | (1ULL << RARCH_MUTE) | (1ULL << RARCH_SAVE_STATE_KEY) | (1ULL << RARCH_LOAD_STATE_KEY) | (1ULL << RARCH_STATE_SLOT_PLUS) | (1ULL << RARCH_STATE_SLOT_MINUS) | (1ULL << RARCH_QUIT_KEY) | (1ULL << RARCH_RMENU_TOGGLE));

         // Read all pending events.
         while (AInputQueue_hasEvents(android_app->inputQueue))
         {
            if (AInputQueue_getEvent(android_app->inputQueue, &event) >= 0)
            {
               bool long_msg_enable = false;
               int32_t handled = 1;
               int action = 0;
               char msg[128];
               int source, id, keycode, type_event, state_id;
               //int predispatched;

               msg[0] = 0;
               //predispatched =AInputQueue_preDispatchEvent(android_app->inputQueue,event);

               //if (predispatched)
               //continue;

               source = AInputEvent_getSource(event);
               id = AInputEvent_getDeviceId(event);
               if (id == zeus_second_id)
                  id = zeus_id;
               keycode = AKeyEvent_getKeyCode(event);

               type_event = AInputEvent_getType(event);
               state_id = -1;

               if (source & (AINPUT_SOURCE_TOUCHSCREEN | AINPUT_SOURCE_MOUSE | AINPUT_SOURCE_TOUCHPAD))
                  state_id = 0; // touch overlay is always player 1
               else
               {
                  for (unsigned i = 0; i < pads_connected; i++)
                     if (state_device_ids[i] == id)
                        state_id = i;
               }

               if (state_id < 0)
               {
                  state_id = pads_connected;
                  state_device_ids[pads_connected++] = id;

                  input_autodetect_setup(android_app, msg, sizeof(msg), state_id, id, source);
                  long_msg_enable = true;
               }

               if (keycode == AKEYCODE_BACK)
               {
                  uint8_t unpacked = (keycode_lut[AKEYCODE_BACK] >> ((state_id+1) << 3)) - 1;
                  uint64_t input_state = (1ULL << unpacked);

                  if (g_extern.lifecycle_mode_state & (1ULL << MODE_INPUT_XPERIA_PLAY_HACK))
                  {
                     int meta = AKeyEvent_getMetaState(event);
                     if (!(meta & AMETA_ALT_ON))
                     {
                        *lifecycle_state |= (1ULL << RARCH_QUIT_KEY);
                        AInputQueue_finishEvent(android_app->inputQueue, event, handled);
                        break;
                     }
                  }
                  else if (type_event == AINPUT_EVENT_TYPE_KEY && input_state < (1ULL << RARCH_FIRST_META_KEY)
                        && input_state > 0)
                  {
                  }
                  else if (g_settings.input.back_behavior == BACK_BUTTON_MENU_TOGGLE)
                  {
                     *lifecycle_state |= (1ULL << RARCH_RMENU_TOGGLE);
                     AInputQueue_finishEvent(android_app->inputQueue, event, handled);
                     break;
                  }
                  else
                  {
                     *lifecycle_state |= (1ULL << RARCH_QUIT_KEY);
                     AInputQueue_finishEvent(android_app->inputQueue, event, handled);
                     break;
                  }
               }

               if (type_event == AINPUT_EVENT_TYPE_MOTION)
               {
                  action = AMotionEvent_getAction(event);
                  size_t motion_pointer = action >> AMOTION_EVENT_ACTION_POINTER_INDEX_SHIFT;
                  action &= AMOTION_EVENT_ACTION_MASK;

                  if (source & ~(AINPUT_SOURCE_TOUCHSCREEN | AINPUT_SOURCE_MOUSE))
                  {
                     if (g_settings.input.dpad_emulation[state_id] != DPAD_EMULATION_NONE)
                        engine_handle_dpad(event, motion_pointer, state_id, msg, sizeof(msg), source, debug_enable);
                  }
                  else
                  {
                     float x = 0.0f;
                     float y = 0.0f;
                     bool keyup = (action == AMOTION_EVENT_ACTION_UP ||
                           action == AMOTION_EVENT_ACTION_CANCEL || action == AMOTION_EVENT_ACTION_POINTER_UP) ||
                        (source == AINPUT_SOURCE_MOUSE && action != AMOTION_EVENT_ACTION_DOWN);

                     if (keyup && motion_pointer < MAX_TOUCH)
                     {
                        memmove(pointer + motion_pointer, pointer + motion_pointer + 1, (MAX_TOUCH - motion_pointer - 1) * sizeof(struct input_pointer));
                        if (pointer_count > 0)
                           pointer_count--;
                     }
                     else
                     {
                        int pointer_max = min(AMotionEvent_getPointerCount(event), MAX_TOUCH);
                        for (motion_pointer = 0; motion_pointer < pointer_max; motion_pointer++)
                        {
                           x = AMotionEvent_getX(event, motion_pointer);
                           y = AMotionEvent_getY(event, motion_pointer);

                           input_translate_coord_viewport(x, y,
                                 &pointer[motion_pointer].x, &pointer[motion_pointer].y,
                                 &pointer[motion_pointer].full_x, &pointer[motion_pointer].full_y);

                           pointer_count = max(pointer_count, motion_pointer + 1);
                        }
                     }
                     if (debug_enable)
                        snprintf(msg, sizeof(msg), "Pad %d : x = %.2f, y = %.2f, src %d.\n", state_id, x, y, source);
                  }

               }
               else if (type_event == AINPUT_EVENT_TYPE_KEY)
               {
                  if (debug_enable)
                     snprintf(msg, sizeof(msg), "Pad %d : %d, ac = %d, src = %d.\n", state_id, keycode, action, source);

                  /* Hack - we have to decrease the unpacked value by 1
                   * because we 'added' 1 to each entry in the LUT -
                   * RETRO_DEVICE_ID_JOYPAD_B is 0
                   */
                  uint8_t unpacked = (keycode_lut[keycode] >> ((state_id+1) << 3)) - 1;
                  uint64_t input_state = (1ULL << unpacked);
                  int action  = AKeyEvent_getAction(event);
                  uint64_t *key = NULL;

                  if(input_state < (1ULL << RARCH_FIRST_META_KEY))
                     key = &state[state_id];
                  else if(input_state)
                     key = &g_extern.lifecycle_state;

                  if(key != NULL)
                  {
                     if (action == AKEY_EVENT_ACTION_UP)
                        *key &= ~(input_state);
                     else if (action == AKEY_EVENT_ACTION_DOWN)
                        *key |= input_state;
                  }

                  if((keycode == AKEYCODE_VOLUME_UP || keycode == AKEYCODE_VOLUME_DOWN) && keycode_lut[keycode] == 0)
                     handled = 0;
               }

               if (msg[0] != 0)
                  msg_queue_push(g_extern.msg_queue, msg, 0, long_msg_enable ? 180 : 30);

               AInputQueue_finishEvent(android_app->inputQueue, event, handled);
            }
         }
      }
      else if (ident == LOOPER_ID_MAIN)
         engine_handle_cmd();
   }
}

static int16_t android_input_state(void *data, const struct retro_keybind **binds, unsigned port, unsigned device, unsigned index, unsigned id)
{
   switch (device)
   {
      case RETRO_DEVICE_JOYPAD:
         return ((state[port] & binds[port][id].joykey) && (port < pads_connected));
      case RETRO_DEVICE_POINTER:
         switch(id)
         {
            case RETRO_DEVICE_ID_POINTER_X:
               return pointer[index].x;
            case RETRO_DEVICE_ID_POINTER_Y:
               return pointer[index].y;
            case RETRO_DEVICE_ID_POINTER_PRESSED:
               return (index < pointer_count) && (pointer[index].x != -0x8000) && (pointer[index].y != -0x8000);
            default:
               return 0;
         }
      case RARCH_DEVICE_POINTER_SCREEN:
         switch(id)
         {
            case RETRO_DEVICE_ID_POINTER_X:
               return pointer[index].full_x;
            case RETRO_DEVICE_ID_POINTER_Y:
               return pointer[index].full_y;
            case RETRO_DEVICE_ID_POINTER_PRESSED:
               return (index < pointer_count) && (pointer[index].full_x != -0x8000) && (pointer[index].full_y != -0x8000);
            default:
               return 0;
         }
      default:
         return 0;
   }
}

static bool android_input_key_pressed(void *data, int key)
{
   return ((g_extern.lifecycle_state | driver.overlay_state) & (1ULL << key));
}

static void android_input_free_input(void *data)
{
   (void)data;
}

const input_driver_t input_android = {
   android_input_init,
   android_input_poll,
   android_input_state,
   android_input_key_pressed,
   android_input_free_input,
   "android_input",
};