/*  RetroArch - A frontend for libretro.
 *  Copyright (C) 2014-2016 - Ali Bouhlel
 *  Copyright (C)      2016 - FIX94
 *
 *  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 <string.h>
#include <malloc.h>
#include <stdint.h>

#include <sndcore2/core.h>
#include <sndcore2/device.h>
#include <sndcore2/drcvs.h>
#include <sndcore2/result.h>
#include <sndcore2/voice.h>
#include <coreinit/time.h>
#include <coreinit/cache.h>
#include <coreinit/thread.h>
#include <coreinit/spinlock.h>

#include "wiiu/wiiu_dbg.h"
#include "wiiu/system/memory.h"
#include "wiiu/multivoice.h"

#include "audio/audio_driver.h"
#include "configuration.h"
#include "performance_counters.h"
#include "runloop.h"

typedef struct
{
   AXMVoice* mvoice;
   uint16_t* buffer_l;
   uint16_t* buffer_r;
   bool nonblocking;

   uint32_t pos;
   uint32_t written;
   OSSpinLock spinlock;
} ax_audio_t;

//4096 samples main buffer, 85ms total
#define AX_AUDIO_COUNT_SHIFT        12u
#define AX_AUDIO_COUNT              (1u << AX_AUDIO_COUNT_SHIFT)
#define AX_AUDIO_COUNT_MASK         (AX_AUDIO_COUNT - 1u)
#define AX_AUDIO_SIZE               (AX_AUDIO_COUNT << 1u)
#define AX_AUDIO_SIZE_MASK          (AX_AUDIO_SIZE - 1u)

#define AX_AUDIO_SAMPLE_COUNT       144 //3ms
#define AX_AUDIO_SAMPLE_MIN         (AX_AUDIO_SAMPLE_COUNT * 6) //18ms
#define AX_AUDIO_SAMPLE_LOAD        (AX_AUDIO_SAMPLE_COUNT * 8) //24ms
#define AX_AUDIO_RATE               48000
//#define ax_audio_ticks_to_samples(ticks)     (((ticks) * 64) / 82875)
//#define ax_audio_samples_to_ticks(samples)   (((samples) * 82875) / 64)

AXResult ax_aux_callback(void* data, ax_audio_t* ax)
{
   OSUninterruptibleSpinLock_Acquire(&ax->spinlock);
   //buffer underrun, stop playback to let if fill up
   if(ax->written < AX_AUDIO_SAMPLE_MIN)
      AXSetMultiVoiceState(ax->mvoice, AX_VOICE_STATE_STOPPED);
   //make sure to update written value if voice is running
   if(AXIsMultiVoiceRunning(ax->mvoice))
      ax->written -= (ax->written < AX_AUDIO_SAMPLE_COUNT ? ax->written : AX_AUDIO_SAMPLE_COUNT);

   OSUninterruptibleSpinLock_Release(&ax->spinlock);
   return AX_RESULT_SUCCESS;
}

static void* ax_audio_init(const char* device, unsigned rate, unsigned latency)
{
   ax_audio_t* ax = (ax_audio_t*)calloc(1, sizeof(ax_audio_t));

   if (!ax)
      return NULL;

   AXInitParams init = {AX_INIT_RENDERER_48KHZ, 0, 0};

   AXInitWithParams(&init);

   u16 setup_buf[0x30] = {0};
   setup_buf[0x25] = 2; //we request 2 channels
   AXAcquireMultiVoice(31, NULL, 0, setup_buf, &ax->mvoice);

   if (!ax->mvoice || ax->mvoice->channels != 2)
   {
      free(ax);
      return NULL;
   }

   ax->buffer_l = MEM1_alloc(AX_AUDIO_SIZE, 0x100);
   ax->buffer_r = MEM1_alloc(AX_AUDIO_SIZE, 0x100);
   memset(ax->buffer_l,0,AX_AUDIO_SIZE);
   memset(ax->buffer_r,0,AX_AUDIO_SIZE);
   DCFlushRange(ax->buffer_l,AX_AUDIO_SIZE);
   DCFlushRange(ax->buffer_r,AX_AUDIO_SIZE);

   //shared by both voices
   AXVoiceOffsets offsets[2];
   offsets[0].currentOffset = 0;
   offsets[0].loopOffset = 0;
   offsets[0].endOffset = AX_AUDIO_COUNT - 1;
   offsets[0].loopingEnabled = AX_VOICE_LOOP_ENABLED;
   offsets[0].dataType = AX_VOICE_FORMAT_LPCM16;
   memcpy(&offsets[1], &offsets[0], sizeof(AXVoiceOffsets));

   //different buffers per voice
   offsets[0].data = ax->buffer_l;
   offsets[1].data = ax->buffer_r;
   AXSetMultiVoiceOffsets(ax->mvoice, offsets);

   AXSetMultiVoiceSrcType(ax->mvoice, AX_VOICE_SRC_TYPE_NONE);
   AXSetMultiVoiceSrcRatio(ax->mvoice, 1.0f);

   AXVoiceVeData ve = {0xF000, 0};
   AXSetMultiVoiceVe(ax->mvoice, &ve);

   AXSetMultiVoiceDeviceMix(ax->mvoice, AX_DEVICE_TYPE_DRC, 0, 0, 0x8000, 0);
   AXSetMultiVoiceDeviceMix(ax->mvoice, AX_DEVICE_TYPE_TV, 0, 0, 0x8000, 0);

   AXSetMultiVoiceState(ax->mvoice, AX_VOICE_STATE_STOPPED);

   ax->pos = 0;
   ax->written = 0;

   config_get_ptr()->audio.out_rate = AX_AUDIO_RATE;

   AXRegisterAuxCallback(AX_DEVICE_TYPE_DRC, 0, 0, (AXAuxCallback)ax_aux_callback, ax);

   OSInitSpinLock(&ax->spinlock);

   return ax;
}

static void ax_audio_free(void* data)
{
   ax_audio_t* ax = (ax_audio_t*)data;

   AXRegisterAuxCallback(AX_DEVICE_TYPE_DRC, 0, 0, NULL, NULL);
   AXFreeMultiVoice(ax->mvoice);
   MEM1_free(ax->buffer_l);
   MEM1_free(ax->buffer_r);
   free(ax);
   AXQuit();
}

static bool ax_audio_stop(void* data)
{
   ax_audio_t* ax = (ax_audio_t*)data;

   AXSetMultiVoiceState(ax->mvoice, AX_VOICE_STATE_STOPPED);
   return true;
}

static bool ax_audio_start(void* data)
{
   ax_audio_t* ax = (ax_audio_t*)data;

   /* Prevents restarting audio when the menu
    * is toggled off on shutdown */

   if (runloop_ctl(RUNLOOP_CTL_IS_SHUTDOWN, NULL))
      return true;

   //set back to playing on enough buffered data
   if(ax->written > AX_AUDIO_SAMPLE_MIN)
      AXSetMultiVoiceState(ax->mvoice, AX_VOICE_STATE_PLAYING);

   return true;
}

static ssize_t ax_audio_write(void* data, const void* buf, size_t size)
{
   static struct retro_perf_counter ax_audio_write_perf = {0};
   ax_audio_t* ax = (ax_audio_t*)data;
   const uint16_t* src = buf;
   int i;

   if(!size || (size & 0x3))
      return 0;

   int count = size >> 2;

   if(count > AX_AUDIO_COUNT)
      count = AX_AUDIO_COUNT;

   size_t countAvail = AX_AUDIO_COUNT - ax->written;
   if (ax->nonblocking)
   {
      if(countAvail < AX_AUDIO_SAMPLE_COUNT)
         return 0;

      if(count > countAvail)
         count = countAvail;
   }
   else if(countAvail < count)
   {
      //sync, wait for free memory
      do {
         OSYieldThread();
         countAvail = AX_AUDIO_COUNT - ax->written;
      } while(AXIsMultiVoiceRunning(ax->mvoice) && countAvail < count);
   }

   performance_counter_init(&ax_audio_write_perf, "ax_audio_write");
   performance_counter_start(&ax_audio_write_perf);

   //write in new data
   size_t startPos = ax->pos;
   int flushP2needed = 0;
   int flushP2 = 0;
   for (i = 0; i < (count << 1); i += 2)
   {
      ax->buffer_l[ax->pos] = src[i];
      ax->buffer_r[ax->pos] = src[i + 1];
      ax->pos++;
      ax->pos &= AX_AUDIO_COUNT_MASK;
      //wrapped around, make sure to store cache
      if(ax->pos == 0)
      {
         flushP2needed = 1;
         flushP2 = ((count << 1) - i);
         DCStoreRangeNoSync(ax->buffer_l+startPos, (AX_AUDIO_COUNT-startPos) << 1);
         DCStoreRangeNoSync(ax->buffer_r+startPos, (AX_AUDIO_COUNT-startPos) << 1);
      }
   }
   //standard cache store case
   if(!flushP2needed)
   {
      DCStoreRangeNoSync(ax->buffer_l+startPos, count << 1);
      DCStoreRange(ax->buffer_r+startPos, count << 1);
   } //store the rest after wrap
   else if(flushP2 > 0)
   {
      DCStoreRangeNoSync(ax->buffer_l, flushP2);
      DCStoreRange(ax->buffer_r, flushP2);
   }
   //add in new audio data
   OSUninterruptibleSpinLock_Acquire(&ax->spinlock);
   ax->written += count;
   OSUninterruptibleSpinLock_Release(&ax->spinlock);

   //possibly buffer underrun
   if(!AXIsMultiVoiceRunning(ax->mvoice))
   {
      //checks if it can be started
      ax_audio_start(ax);
   }

   performance_counter_stop(&ax_audio_write_perf);

   return (count << 2);
}

static bool ax_audio_alive(void* data)
{
   ax_audio_t* ax = (ax_audio_t*)data;
   return AXIsMultiVoiceRunning(ax->mvoice);
}

static void ax_audio_set_nonblock_state(void* data, bool state)
{
   ax_audio_t* ax = (ax_audio_t*)data;

   if (ax)
   {
      ax->nonblocking = state;
   }
}

static bool ax_audio_use_float(void* data)
{
   (void)data;
   return false;
}

static size_t ax_audio_write_avail(void* data)
{
   ax_audio_t* ax = (ax_audio_t*)data;

   size_t ret = AX_AUDIO_COUNT - ax->written;

   return (ret < AX_AUDIO_SAMPLE_COUNT ? 0 : ret);
}

static size_t ax_audio_buffer_size(void* data)
{
   (void)data;
   return AX_AUDIO_COUNT;
}


audio_driver_t audio_ax =
{
   ax_audio_init,
   ax_audio_write,
   ax_audio_stop,
   ax_audio_start,
   ax_audio_alive,
   ax_audio_set_nonblock_state,
   ax_audio_free,
   ax_audio_use_float,
   "AX",
   NULL,
   NULL,
//   ax_audio_write_avail,
//   ax_audio_buffer_size
};