/*
 * Copyright (C) 2010 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *	  http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *
 */

/* This is a JNI example where we use native methods to play sounds
 * using OpenSL ES. See the corresponding Java source file located at:
 *
 *   src/com/example/nativeaudio/NativeAudio/NativeAudio.java
 */

#include <assert.h>
#include <string.h>

// for __android_log_print(ANDROID_LOG_INFO, "YourApp", "formatted message");
// #include <android/log.h>

// for native audio
#include <SLES/OpenSLES.h>
#include <SLES/OpenSLES_Android.h>

#include "../base/logging.h"

// engine interfaces
static SLObjectItf engineObject = NULL;
static SLEngineItf engineEngine;

// output mix interfaces
static SLObjectItf outputMixObject = NULL;
static SLEnvironmentalReverbItf outputMixEnvironmentalReverb = NULL;

// buffer queue player interfaces
static SLObjectItf bqPlayerObject = NULL;
static SLPlayItf bqPlayerPlay;
static SLAndroidSimpleBufferQueueItf bqPlayerBufferQueue;
static SLMuteSoloItf bqPlayerMuteSolo;
static SLVolumeItf bqPlayerVolume;

// synthesized sawtooth clip
#define SAWTOOTH_FRAMES 8000
static short sawtoothBuffer[SAWTOOTH_FRAMES];

// pointer and size of the next player buffer to enqueue, and number of remaining buffers
static short *nextBuffer;
static unsigned nextSize;

// synthesize a mono sawtooth wave and place it into a buffer (called automatically on load)
__attribute__((constructor)) static void onDlOpen(void)
{
	ILOG("Buffer callback");
	unsigned int i;
	for (i = 0; i < SAWTOOTH_FRAMES; ++i) {
		sawtoothBuffer[i] = 32768 - ((i % 100) * 660);
	}
}

// this callback handler is called every time a buffer finishes playing
void bqPlayerCallback(SLAndroidSimpleBufferQueueItf bq, void *context)
{
	assert(bq == bqPlayerBufferQueue);
	assert(NULL == context);


	nextBuffer = sawtoothBuffer;
	nextSize = sizeof(sawtoothBuffer);
	SLresult result;
	// enqueue another buffer
	result = (*bqPlayerBufferQueue)->Enqueue(bqPlayerBufferQueue, nextBuffer, nextSize);
	// the most likely other result is SL_RESULT_BUFFER_INSUFFICIENT,
	// which for this code example would indicate a programming error
	assert(SL_RESULT_SUCCESS == result);
}

// create the engine and output mix objects
extern "C" bool OpenSLWrap_Init()
{
	SLresult result;

	// create engine
	result = slCreateEngine(&engineObject, 0, NULL, 0, NULL, NULL);
	assert(SL_RESULT_SUCCESS == result);

	// realize the engine
	result = (*engineObject)->Realize(engineObject, SL_BOOLEAN_FALSE);
	assert(SL_RESULT_SUCCESS == result);

	// get the engine interface, which is needed in order to create other objects
	result = (*engineObject)->GetInterface(engineObject, SL_IID_ENGINE, &engineEngine);
	assert(SL_RESULT_SUCCESS == result);

	// create output mix, with environmental reverb specified as a non-required interface
	result = (*engineEngine)->CreateOutputMix(engineEngine, &outputMixObject, 0, 0, 0);
	assert(SL_RESULT_SUCCESS == result);

	// realize the output mix
	result = (*outputMixObject)->Realize(outputMixObject, SL_BOOLEAN_FALSE);
	assert(SL_RESULT_SUCCESS == result);

	// create buffer queue audio player
	// ================================

	// configure audio source
	SLDataLocator_AndroidSimpleBufferQueue loc_bufq = {SL_DATALOCATOR_ANDROIDSIMPLEBUFFERQUEUE, 2};
	
	// TODO: This is all wrong.
	SLDataFormat_PCM format_pcm = {
		  SL_DATAFORMAT_PCM,
			1,
			SL_SAMPLINGRATE_8,
	SL_PCMSAMPLEFORMAT_FIXED_16,
			SL_PCMSAMPLEFORMAT_FIXED_16,
	SL_SPEAKER_FRONT_CENTER,
			SL_BYTEORDER_LITTLEENDIAN};

	SLDataSource audioSrc = {&loc_bufq, &format_pcm};

	// configure audio sink
	SLDataLocator_OutputMix loc_outmix = {SL_DATALOCATOR_OUTPUTMIX, outputMixObject};
	SLDataSink audioSnk = {&loc_outmix, NULL};

	// create audio player
	const SLInterfaceID ids[2] = {SL_IID_BUFFERQUEUE, SL_IID_VOLUME};
	const SLboolean req[2] = {SL_BOOLEAN_TRUE, SL_BOOLEAN_TRUE};
	result = (*engineEngine)->CreateAudioPlayer(engineEngine, &bqPlayerObject, &audioSrc, &audioSnk,
			2, ids, req);
	assert(SL_RESULT_SUCCESS == result);

	// realize the player
	result = (*bqPlayerObject)->Realize(bqPlayerObject, SL_BOOLEAN_FALSE);
	assert(SL_RESULT_SUCCESS == result);

	// get the play interface
	result = (*bqPlayerObject)->GetInterface(bqPlayerObject, SL_IID_PLAY, &bqPlayerPlay);
	assert(SL_RESULT_SUCCESS == result);

	// get the buffer queue interface
	result = (*bqPlayerObject)->GetInterface(bqPlayerObject, SL_IID_BUFFERQUEUE,
			&bqPlayerBufferQueue);
	assert(SL_RESULT_SUCCESS == result);

	// register callback on the buffer queue
	result = (*bqPlayerBufferQueue)->RegisterCallback(bqPlayerBufferQueue, bqPlayerCallback, NULL);
	assert(SL_RESULT_SUCCESS == result);

	// get the volume interface
	result = (*bqPlayerObject)->GetInterface(bqPlayerObject, SL_IID_VOLUME, &bqPlayerVolume);
	assert(SL_RESULT_SUCCESS == result);

	// set the player's state to playing
	result = (*bqPlayerPlay)->SetPlayState(bqPlayerPlay, SL_PLAYSTATE_PLAYING);
	assert(SL_RESULT_SUCCESS == result);

	// Enqueue a first buffer.
	result = (*bqPlayerBufferQueue)->Enqueue(bqPlayerBufferQueue, sawtoothBuffer, sizeof(sawtoothBuffer));
	if (SL_RESULT_SUCCESS != result) {
		return false;
	}
	return true;
}

// shut down the native audio system
extern "C" void OpenSLWrap_Shutdown()
{
	// destroy buffer queue audio player object, and invalidate all associated interfaces
	if (bqPlayerObject != NULL) {
		(*bqPlayerObject)->Destroy(bqPlayerObject);
		bqPlayerObject = NULL;
		bqPlayerPlay = NULL;
		bqPlayerBufferQueue = NULL;
		bqPlayerMuteSolo = NULL;
		bqPlayerVolume = NULL;
	}

	// destroy output mix object, and invalidate all associated interfaces
	if (outputMixObject != NULL) {
		(*outputMixObject)->Destroy(outputMixObject);
		outputMixObject = NULL;
		outputMixEnvironmentalReverb = NULL;
	}

	// destroy engine object, and invalidate all associated interfaces
	if (engineObject != NULL) {
		(*engineObject)->Destroy(engineObject);
		engineObject = NULL;
		engineEngine = NULL;
	}
}