// EasySound.cpp: implementation of the CEasySound class.
//
//////////////////////////////////////////////////////////////////////
#include "EasySound.h"
#include <cstdio>

extern void mixaudio(void* unused, Uint8* stream, int len) {
    CEasySound::Instance()->CallMixAudio(unused, stream, len);
}

//////////////////////////////////////////////////////////////////////
// Member for Singleton Pattern
//////////////////////////////////////////////////////////////////////

CEasySound* CEasySound::_instance = NULL;

//////////////////////////////////////////////////////////////////////
// Construction/Destruction
//////////////////////////////////////////////////////////////////////

CEasySound::CEasySound() {
    if ((SDL_Init(SDL_INIT_VIDEO | SDL_INIT_AUDIO | SDL_INIT_NOPARACHUTE)
         == -1)) {
        fprintf(stderr, "Unable to init SDL: %s\n", SDL_GetError());
        exit(1);
    }
    atexit(SDL_Quit);

    /* Open the audio device */

    /* 22050Hz - FM Radio quality */
    desired.freq = ES_FREQ;

    /* 16-bit signed audio */
    desired.format = AUDIO_S16;

    /* Mono */
    desired.channels = 2;

    /* Large audio buffer reduces risk of dropouts but increases response time
     */
    desired.samples = ES_SAMPLE;

    desired.callback = mixaudio;

    desired.userdata = NULL;
    /* Open the audio device */
    if (SDL_OpenAudio(&desired, &obtained) < 0) {
        fprintf(stderr, "Couldn't open audio: %s\n", SDL_GetError());
        exit(-1);
    }
}

CEasySound::~CEasySound() {
    SDL_Quit();
    delete _instance;
    _instance = NULL;
}

CEasySound* CEasySound::Instance() {
    if (_instance == NULL)
        _instance = new CEasySound();
    return _instance;
}

void CEasySound::CallMixAudio(void*, Uint8* stream, int len) {
    // int i;
    Uint32 amount, data_len, data_pos;

    std::list<CSound*>::iterator cs;
    for (cs = m_listSound.begin(); cs != m_listSound.end(); ++cs) {
        // data_len = (*cs)->GetLength().GetSDLTime();
        data_len = (*cs)->m_stop.GetSDLTime();
        data_pos = (*cs)->m_pos.GetSDLTime();
        amount = (data_len - data_pos);
        if (amount > (Uint32)len) {
            amount = len;
        }
        Uint8* data = &(*cs)->m_data[data_pos];
        SDL_MixAudio(stream, data, amount, SDL_MIX_MAXVOLUME);
        (*cs)->m_pos = CSoundTime(data_pos + amount);
    }
}

int CEasySound::Load(const string& filename) {
    // find ID for sound
    std::list<CSound*>::iterator cs;
    int iSoundID = 0;
    bool bFoundID = true;
    while (bFoundID) {  // while loop until if there no ID match and set that ID
                        // for new sound's ID
        bFoundID = false;
        for (cs = m_listSound.begin(); cs != m_listSound.end(); ++cs) {
            if ((*cs)->GetSoundID() == iSoundID) {
                bFoundID = true;
                iSoundID++;
                break;
            }
        }
    }

    // load the sound with new ID
    CSound* sound = new CSound(filename, iSoundID);
    if (sound->GetLength() == CSoundTime(0, 0, 0)) {
        return -1;  // fail to load
    }
    m_listSound.insert(m_listSound.end(), sound);
    return iSoundID;  // fail to load
}

void CEasySound::Unload(int iSoundID) {
    std::list<CSound*>::iterator cs;
    for (cs = m_listSound.begin(); cs != m_listSound.end(); ++cs) {
        if ((*cs)->GetSoundID() == iSoundID) {
            delete (*cs);
            m_listSound.erase(cs);
            return;
        }
    }
}

void CEasySound::Unload(CSound* sound) {
    std::list<CSound*>::iterator cs;
    for (cs = m_listSound.begin(); cs != m_listSound.end(); ++cs) {
        if ((*cs)->GetSoundID() == sound->GetSoundID()) {
            delete (*cs);
            m_listSound.erase(cs);
            return;
        }
    }
}

CSound* CEasySound::GetSound(int iSoundID) {
    std::list<CSound*>::iterator cs;
    for (cs = m_listSound.begin(); cs != m_listSound.end(); ++cs) {
        if ((*cs)->GetSoundID() == iSoundID) {
            return (*cs);
        }
    }

    return nullptr;  // empty sound
}