/* FAudioGMS - Game Maker FAudio bindings in C
 *
 * Copyright (c) 2021 Evan Hemsley
 *
 * This software is provided 'as-is', without any express or implied warranty.
 * In no event will the authors be held liable for any damages arising from
 * the use of this software.
 *
 * Permission is granted to anyone to use this software for any purpose,
 * including commercial applications, and to alter it and redistribute it
 * freely, subject to the following restrictions:
 *
 * 1. The origin of this software must not be misrepresented; you must not
 * claim that you wrote the original software. If you use this software in a
 * product, an acknowledgment in the product documentation would be
 * appreciated but is not required.
 *
 * 2. Altered source versions must be plainly marked as such, and must not be
 * misrepresented as being the original software.
 *
 * 3. This notice may not be removed or altered from any source distribution.
 *
 * Evan "cosmonaut" Hemsley <evan@moonside.games>
 *
 */

#include "FAudioGMS.h"
#include "../lib/FAudio/include/FAPOBase.h"
#include "../lib/FAudio/include/FAudioFX.h"
#include "../lib/FAudio/include/F3DAudio.h"
#include "../lib/FAudio/include/FAudio.h"

#define DR_WAV_IMPLEMENTATION
#include "../lib/dr_wav.h"

#include <stdlib.h>
#include <stdio.h>

static inline void Log(char *string)
{
    printf("%s", string);
    fflush(stdout);
}

typedef enum FAudioGMS_SoundState
{
    SoundState_Playing,
    SoundState_Paused,
    SoundState_Stopped
} FAudioGMS_SoundState;

typedef struct FAudioGMS_StaticSound
{
    uint32_t id;
    FAudioBuffer buffer;
    uint32_t channels;
    uint32_t samplesPerSecond;
    uint32_t loopStart;
    uint32_t loopLength;
} FAudioGMS_StaticSound;

typedef struct FAudioGMS_SoundInstance
{
    uint32_t id;
    FAudioSourceVoice *handle;
    FAudioWaveFormatEx format;
    uint8_t loop; /* bool */
    FAudioGMS_SoundState soundState;
    F3DAUDIO_DSP_SETTINGS dspSettings;

    float pan;
    float pitch;
    float volume;
    float reverb;
    float lowPassFilter;
    float highPassFilter;
    float bandPassFilter;
} FAudioGMS_SoundInstance;

typedef struct FAudioGMS_Device
{
    FAudio* handle;
    FAudioDeviceDetails deviceDetails;
    FAudioMasteringVoice *masteringVoice;
    FAudioSubmixVoice *reverbVoice;
    FAudioVoiceSends reverbSends;

    FAudioGMS_StaticSound **staticSounds;
    uint32_t staticSoundCount;

    FAudioGMS_SoundInstance **staticSoundInstances;
    uint32_t staticSoundInstanceCount;
} FAudioGMS_Device;

static FAudioGMS_Device *device = NULL;

void FAudioGMS_Init()
{
    device = malloc(sizeof(FAudioGMS_Device));

    uint32_t result = FAudioCreate(&device->handle, 0, FAUDIO_DEFAULT_PROCESSOR);

    if (result != 0)
    {
        Log("Failed to create device! Bailing!");
        free(device);
        device = NULL;
        return;
    }

    /* Find a suitable device */

    uint32_t deviceCount;
    FAudio_GetDeviceCount(device->handle, &deviceCount);

    if (deviceCount == 0)
    {
        Log("No audio devices found! Bailing!");
        FAudio_Release(device->handle);
        free(device);
        device = NULL;
        return;
    }

    FAudioDeviceDetails deviceDetails;

    uint32_t i = 0;
    for (i = 0; i < deviceCount; i += 1)
    {
        FAudio_GetDeviceDetails(
            device->handle,
            i,
            &deviceDetails);

        if ((deviceDetails.Role & FAudioDefaultGameDevice) == FAudioDefaultGameDevice)
        {
            device->deviceDetails = deviceDetails;
            break;
        }
    }

    if (i == deviceCount)
    {
        i = 0; /* whatever we'll just use the first one i guess */
        FAudio_GetDeviceDetails(
            device->handle,
            i,
            &deviceDetails);

        device->deviceDetails = deviceDetails;
    }

    if (FAudio_CreateMasteringVoice(
        device->handle,
        &device->masteringVoice,
        FAUDIO_DEFAULT_CHANNELS,
        FAUDIO_DEFAULT_SAMPLERATE,
        0,
        i,
        NULL
    ) != 0)
    {
        Log("No mastering voice found! Bailing!");
        FAudio_Release(device->handle);
        free(device);
        device = NULL;
        return;
    }

    /* Init reverb */

    FAPO *reverb = malloc(sizeof(FAPO));

    FAudioCreateReverb(&reverb, 0);

    FAudioEffectChain *reverbChain = malloc(sizeof(FAudioEffectChain));

    reverbChain->EffectCount = 1;
    reverbChain->pEffectDescriptors = malloc(sizeof(FAudioEffectDescriptor));

    FAudioEffectDescriptor *reverbDescriptor = reverbChain->pEffectDescriptors;

    reverbDescriptor->InitialState = 1;
    reverbDescriptor->OutputChannels = device->deviceDetails.OutputFormat.Format.nChannels == 6 ? 6 : 1;
    reverbDescriptor->pEffect = reverb;

    FAudio_CreateSubmixVoice(
        device->handle,
        &device->reverbVoice,
        1, /* omnidirectional reverb */
        device->deviceDetails.OutputFormat.Format.nSamplesPerSec,
        0,
        0,
        NULL,
        reverbChain);

    FAPOBase_Release((FAPOBase*)reverb);
    free(reverb);
    free(reverbChain->pEffectDescriptors);
    free(reverbChain);

    FAudioFXReverbParameters *reverbParams = malloc(sizeof(FAudioFXReverbParameters));

    reverbParams->WetDryMix = 100.0f;
    reverbParams->ReflectionsDelay = 7;
    reverbParams->ReverbDelay = 11;
    reverbParams->RearDelay = FAUDIOFX_REVERB_DEFAULT_REAR_DELAY;
    reverbParams->PositionLeft = FAUDIOFX_REVERB_DEFAULT_POSITION;
    reverbParams->PositionRight = FAUDIOFX_REVERB_DEFAULT_POSITION;
    reverbParams->PositionMatrixLeft = FAUDIOFX_REVERB_DEFAULT_POSITION_MATRIX;
    reverbParams->PositionMatrixRight = FAUDIOFX_REVERB_DEFAULT_POSITION_MATRIX;
    reverbParams->EarlyDiffusion = 15;
    reverbParams->LateDiffusion = 15;
    reverbParams->LowEQGain = 8;
    reverbParams->LowEQCutoff = 4;
    reverbParams->HighEQGain = 8;
    reverbParams->HighEQCutoff = 6;
    reverbParams->RoomFilterFreq = 5000.0f;
    reverbParams->RoomFilterMain = -10.0f;
    reverbParams->RoomFilterHF = -1.0f;
    reverbParams->ReflectionsGain = -26.0200005f;
    reverbParams->ReverbGain = 10.0f;
    reverbParams->DecayTime = 1.49000001f;
    reverbParams->Density = 100.0f;
    reverbParams->RoomSize = FAUDIOFX_REVERB_DEFAULT_ROOM_SIZE;

    FAudioVoice_SetEffectParameters(
        device->reverbVoice,
        0,
        reverbParams,
        sizeof(FAudioFXReverbParameters),
        0);

    free(reverbParams);

    /* Init reverb sends */

    device->reverbSends.SendCount = 2;
    device->reverbSends.pSends = malloc(2 * sizeof(FAudioSendDescriptor));

    device->reverbSends.pSends[0].Flags = 0;
    device->reverbSends.pSends[0].pOutputVoice = device->masteringVoice;
    device->reverbSends.pSends[1].Flags = 0;
    device->reverbSends.pSends[1].pOutputVoice = device->reverbVoice;

    device->staticSounds = NULL;
    device->staticSoundCount = 0;

    Log("FAudio initialized successfully!");
}

void FAudioGMS_Update()
{

}

/* Taken from https://github.com/FNA-XNA/FNA/blob/master/src/Audio/SoundEffectInstance.cs */
static void SetPanMatrixCoefficients(FAudioGMS_SoundInstance *instance)
{
    /* Two major things to notice:
    * 1. The spec assumes any speaker count >= 2 has Front Left/Right.
    * 2. Stereo panning is WAY more complicated than you think.
    *    The main thing is that hard panning does NOT eliminate an
    *    entire channel; the two channels are blended on each side.
    * -flibit
    */

    float* outputMatrix = (float*) instance->dspSettings.pMatrixCoefficients;
    if (instance->dspSettings.SrcChannelCount == 1)
    {
        if (instance->dspSettings.DstChannelCount == 1)
        {
            outputMatrix[0] = 1.0f;
        }
        else
        {
            outputMatrix[0] = (instance->pan > 0.0f) ? (1.0f - instance->pan) : 1.0f;
            outputMatrix[1] = (instance->pan < 0.0f) ? (1.0f  + instance->pan) : 1.0f;
        }
    }
    else
    {
        if (instance->dspSettings.DstChannelCount == 1)
        {
            outputMatrix[0] = 1.0f;
            outputMatrix[1] = 1.0f;
        }
        else
        {
            if (instance->pan <= 0.0f)
            {
                // Left speaker blends left/right channels
                outputMatrix[0] = 0.5f * instance->pan + 1.0f;
                outputMatrix[1] = 0.5f * -instance->pan;
                // Right speaker gets less of the right channel
                outputMatrix[2] = 0.0f;
                outputMatrix[3] = instance->pan + 1.0f;
            }
            else
            {
                // Left speaker gets less of the left channel
                outputMatrix[0] = -instance->pan + 1.0f;
                outputMatrix[1] = 0.0f;
                // Right speaker blends right/left channels
                outputMatrix[2] = 0.5f * instance->pan;
                outputMatrix[3] = 0.5f * -instance->pan + 1.0f;
            }
        }
    }
}

double FAudioGMS_StaticSound_LoadWAV(char *filePath)
{
    drwav_uint64 frameCount;

    FAudioGMS_StaticSound *sound = malloc(sizeof(FAudioGMS_StaticSound));
    float *pSampleData = drwav_open_file_and_read_pcm_frames_f32(filePath, &sound->channels, &sound->samplesPerSecond, &frameCount, NULL);
    if (pSampleData == NULL)
    {
        Log("Error opening WAV file: ");
        Log(filePath);
    }

    sound->buffer.AudioBytes = (uint32_t)(frameCount * sizeof(float));
    sound->buffer.Flags = FAUDIO_END_OF_STREAM;
    sound->buffer.LoopBegin = 0;
    sound->buffer.LoopCount = 0;
    sound->buffer.LoopLength = 0;
    sound->buffer.pAudioData = (uint8_t*) pSampleData;
    sound->buffer.pContext = NULL;
    sound->buffer.PlayBegin = 0;
    sound->buffer.PlayLength = 0;

    sound->loopStart = 0;
    sound->loopLength = 0;

    /* FIXME: id re-use system */
    sound->id = device->staticSoundCount;

    device->staticSounds = realloc(device->staticSounds, (device->staticSoundCount + 1) * sizeof(FAudioGMS_StaticSound*));
    device->staticSounds[device->staticSoundCount] = sound;
    device->staticSoundCount += 1;

    return (double)sound->id;
}

double FAudioGMS_SoundInstance_CreateFromStaticSound(double id)
{
    FAudioGMS_StaticSound *staticSound = device->staticSounds[(uint32_t)id];
    FAudioGMS_SoundInstance *instance = malloc(sizeof(FAudioGMS_SoundInstance));

    instance->handle = NULL;
    instance->format.wFormatTag = 3;
    instance->format.wBitsPerSample = 32;
    instance->format.nChannels = staticSound->channels;
    instance->format.nBlockAlign = (uint16_t)(4 * staticSound->channels);
    instance->format.nSamplesPerSec = staticSound->samplesPerSecond;
    instance->format.nAvgBytesPerSec = instance->format.nBlockAlign * staticSound->samplesPerSecond;

    FAudio_CreateSourceVoice(
        device->handle,
        &instance->handle,
        &instance->format,
        FAUDIO_VOICE_USEFILTER,
        FAUDIO_DEFAULT_FREQ_RATIO,
        NULL,
        NULL,
        NULL);

    if (instance->handle == NULL)
    {
        Log("SoundInstance failed to initialize!");
        free(instance);
        return -1;
    }

    instance->dspSettings.DopplerFactor = 1.0f;
    instance->dspSettings.SrcChannelCount = staticSound->channels;
    instance->dspSettings.DstChannelCount = device->deviceDetails.OutputFormat.Format.nChannels;

    uint32_t memsize = 4 * instance->dspSettings.SrcChannelCount * instance->dspSettings.DstChannelCount;
    instance->dspSettings.pMatrixCoefficients = malloc(memsize);
    memset(instance->dspSettings.pMatrixCoefficients, 0, memsize);

    SetPanMatrixCoefficients(instance);

    FAudioVoice_SetOutputVoices(
        instance->handle,
        &device->reverbSends);

    instance->soundState = SoundState_Stopped;

    /* FIXME: id re-use system */
    instance->id = device->staticSoundInstanceCount;

    device->staticSoundInstances = realloc(device->staticSoundInstances, (device->staticSoundCount + 1) * sizeof(FAudioGMS_SoundInstance*));
    device->staticSoundInstances[device->staticSoundInstanceCount] = instance;
    device->staticSoundInstanceCount += 1;

    return (double)instance->id;
}

void FAudioGMS_SoundInstance_Destroy(double id)
{
    FAudioGMS_SoundInstance *instance = device->staticSoundInstances[(uint32_t)id];

    if (instance != NULL)
    {
        FAudioVoice_DestroyVoice(instance->handle);
        free(instance->dspSettings.pMatrixCoefficients);
        free(instance);
        device->staticSoundInstances[(uint32_t)id] = NULL;
    }
}

void FAudioGMS_StaticSound_Destroy(double id)
{
    FAudioGMS_StaticSound *sound = device->staticSounds[(uint32_t)id];

    if (sound != NULL)
    {
        free((void*)sound->buffer.pAudioData);
        free(sound);
        device->staticSounds[(uint32_t)id] = NULL;
    }
}

void FAudioGMS_Destroy()
{
    FAudio_Release(device->handle);
    free(device);
    device = NULL;
}