#include "dmsimple.h"


DMEngineData engine;
DMFrameData frame;


int engineShowProgress(int loaded, int total)
{
    int dx = 60,
        dh = 20,
        dw = engine.screen->w - (2 * dx),
        dy = (engine.screen->h - dh) / 2;
    
    if (SDL_MUSTLOCK(engine.screen) != 0 && SDL_LockSurface(engine.screen) != 0)
        return DMERR_INIT_FAIL;
    
    // Draw the progress bar
    dmClearSurface(engine.screen, dmMapRGBA(engine.screen, 0,0,0,0));
    dmFillRect(engine.screen, dx, dy, dx+dw, dy+dh, dmMapRGB(engine.screen, 255,255,255));
    dmFillRect(engine.screen, dx+1, dy+1, dx+dw-1, dy+dh-1, dmMapRGB(engine.screen, 0,0,0));

    if (total > 0)
    {
        dmFillRect(engine.screen,
            dx+3, dy+3,
            dx + 3 + ((dw - 3) * loaded) / total,
            dy + dh - 3,
            dmMapRGB(engine.screen, 200,200,200));
    }

    // Flip screen
    if (SDL_MUSTLOCK(engine.screen) != 0)
        SDL_UnlockSurface(engine.screen);

    SDL_Flip(engine.screen);
    return DMERR_OK;
}


int engineLoadResources()
{
    int err, loaded, total;
    
    err = dmres_preload(TRUE, &loaded, &total);

    while ((err = dmres_preload(FALSE, &loaded, &total)) == DMERR_PROGRESS)
    {
        // Show a nice progress bar while loading
        if (total > 0 && (loaded % 2) == 0)
        {
            if ((err = engineShowProgress(loaded, total)) != DMERR_OK)
                return err;
        }
    }
    
    return err;
}


int engineGetTick()
{
    return (frame.startTime - engine.startTime) + engine.adjustTime;
}


float engineGetTimeDT()
{
    return (float) engineGetTick() / 1000.0f;
}


int engineGetTimeDTi()
{
    return (float) engineGetTick() / 1000;
}


int engineGetTime(int t)
{
    return engineGetTick() - (1000 * t);
}


int engineGetDT(int t)
{
    return engineGetTime(t) / 1000;
}


static int engineResImageLoad(DMResource *res)
{
    SDL_Surface *img = dmLoadImage(res);
    if (res != NULL)
    {
        res->rdata = img;
        return DMERR_OK;
    }
    else
        return dmferror(res);
}

static void engineResImageFree(DMResource *res)
{
    SDL_FreeSurface((SDL_Surface *)res->rdata);
}

static int engineResModuleLoad(DMResource *res)
{
    return jssLoadXM(res, (JSSModule **) &(res->rdata));
}

static void engineResModuleFree(DMResource *res)
{
    jssFreeModule((JSSModule *) res->rdata);
}


static DMResourceDataOps engineResImage =
{
    engineResImageLoad,
    engineResImageFree
};

static DMResourceDataOps engineResModule =
{
    engineResModuleLoad,
    engineResModuleFree
};


static int engineClassifier(DMResource *res)
{
    DMResourceDataOps *rops = NULL;
    char *fext;

    if (res == NULL)
        return DMERR_NULLPTR;
    
    if ((fext = strrchr(res->filename, '.')) != NULL)
    {
        if (strcasecmp(fext, ".png") == 0 || strcasecmp(fext, ".jpg") == 0)
            rops = &engineResImage;
        else
        if (strcasecmp(fext, ".xm") == 0 || strcasecmp(fext, ".jmod") == 0)
            rops = &engineResModule;
    }
    
    res->rops = rops;
    
    return DMERR_OK;
}


void *engineGetResource(const char *name)
{
    DMResource *res = dmres_find(name);
    if (res != NULL && res->rdata != NULL)
        return res->rdata;
    else
    {
        dmError("Could not find resource '%s'.\n", name);
        return NULL;
    }
}


#ifdef DM_DEBUG
static void engineAudioCallbackStream(void *userdata, Uint8 *stream, int len)
{
    if (engine.paused)
    {
        memset(stream, 0, len);
    }
    else
    {
        JSSMixer *d = (JSSMixer *) userdata;
        if (d != NULL)
        {
            int pos = ((engine.adjustTime * d->outFreq) / 1000) * jvmGetSampleSize(d) +
                engine.audioSamples;
            
            memcpy(stream, engine.audioBuf + pos, len);

            engine.audioSamples += len;
        }
    }
}

void engineAdjustTime(int adj)
{
    if (engine.optDebug)
    {
        int tmp = engine.adjustTime + adj;
        if (tmp < 0)
            tmp = 0;
        else
        if (tmp >= engine.demoDuration * 1000)
            tmp = engine.demoDuration * 1000;

        engine.pauseFlag = TRUE;
        engine.adjustTime = tmp;
        dmPrint(0, "adj=%d, adjtime=%d\n", adj, engine.adjustTime);
    }
}
#endif


static void engineAudioCallback(void *userdata, Uint8 *stream, int len)
{
    if (engine.paused)
    {
        memset(stream, 0, len);
    }
    else
    {
        JSSMixer *d = (JSSMixer *) userdata;
        if (d != NULL)
            jvmRenderAudio(d, stream, len / jvmGetSampleSize(d));
    }
}


int main(int argc, char *argv[])
{
    int err;
    BOOL initSDL = FALSE;
    SDL_AudioSpec afmt;

    memset(&afmt, 0, sizeof(afmt));
    memset(&frame, 0, sizeof(frame));
    memset(&engine, 0, sizeof(engine));

    // Pre-initialization
    if ((err = demoPreInit(argc, argv)) != DMERR_OK)
        goto error_exit;

    // Initialize resource subsystem
    dmPrint(1, "Initializing resources subsystem.\n");
    if ((err = dmres_init("orvellys.dat", NULL, DRF_USE_PACK | DRF_PRELOAD_RES, engineClassifier)) != DMERR_OK)
    {
        dmError("Could not initialize resource manager: %d, %s.\n", err, dmErrorStr(err));
        goto error_exit;
    }

    // Initialize SDL components
    if (SDL_Init(SDL_INIT_VIDEO | SDL_INIT_AUDIO | SDL_INIT_TIMER) != 0)
    {
        dmError("Could not initialize SDL: %s\n", SDL_GetError());
        goto error_exit;
    }
    initSDL = TRUE;

    // Initialize JSS
    jssInit();

    afmt.freq     = 44100;
    afmt.format   = AUDIO_S16SYS;
    afmt.channels = 2;
    afmt.samples  = 16*1024;

    dmPrint(1, "Initializing miniJSS mixer with: %d, %d, %d\n",
        JSS_AUDIO_S16, afmt.channels, afmt.freq);

    if ((engine.dev = jvmInit(JSS_AUDIO_S16, afmt.channels, afmt.freq, JMIX_AUTO)) == NULL)
    {
        dmError("jvmInit() returned NULL, voi perkele.\n");
        goto error_exit;
    }

    if ((engine.plr = jmpInit(engine.dev)) == NULL)
    {
        dmError("jmpInit() returned NULL\n");
        goto error_exit;
    }

    // Initialize SDL audio
    dmPrint(1, "Trying to init SDL audio with: %d, %d, %d\n",
        afmt.format, afmt.channels, afmt.freq);

#ifdef DM_DEBUG
    if (engine.optDebug)
    {
        afmt.callback = engineAudioCallbackStream;
        afmt.userdata = (void *) engine.dev;
    }
    else
#endif
    {
        afmt.callback = engineAudioCallback;
        afmt.userdata = (void *) engine.dev;
    }
    
    if (SDL_OpenAudio(&afmt, NULL) < 0)
    {
        dmError("Couldn't open audio: %s\n", SDL_GetError());
        goto error_exit;
    }

    // Initialize SDL video
    dmPrint(1, "Initializing SDL video %d x %d x %dbpp, flags=0x%08x\n",
        engine.optScrWidth, engine.optScrHeight, engine.optBitDepth, engine.optVFlags);

    engine.screen = SDL_SetVideoMode(engine.optScrWidth, engine.optScrHeight, engine.optBitDepth, engine.optVFlags);
    if (engine.screen == NULL)
    {
        dmError("Can't SDL_SetVideoMode(): %s\n", SDL_GetError());
        goto error_exit;
    }

    SDL_ShowCursor(SDL_DISABLE);
    SDL_WM_SetCaption(dmProgDesc, dmProgName);


    // Load resources
    if ((err = engineLoadResources()) != DMERR_OK)
    {
        dmError("Error loading resources, %d: %s.\n",
            err, dmErrorStr(err));
        goto error_exit;
    }

    // Final initializations
    if ((err = demoInit()) != DMERR_OK)
        goto error_exit;

#ifdef DM_DEBUG
    if (engine.optDebug)
    {
        Uint8 *ptr;
        int left = engine.dev->outFreq * engine.demoDuration;
        engine.audioBufSize = jvmGetSampleSize(engine.dev) * engine.dev->outFreq * engine.demoDuration;
        if ((engine.audioBuf = dmMalloc(engine.audioBufSize)) == NULL)
        {
            dmError("Could not allocate audio stream buffer of %d bytes.\n",
                engine.audioBufSize);
            goto error_exit;
        }
        
        ptr = engine.audioBuf;
        while (left > 0)
        {
            int length = left;
            if (length > 16*1024)
                length = 16*1024;

            jvmRenderAudio(engine.dev, ptr, length);
            ptr += jvmGetSampleSize(engine.dev) * length;
            left -= length;
        }
    }
#endif

    SDL_PauseAudio(0);
    engine.startTime = SDL_GetTicks();

    while (!engine.exitFlag)
    {
        while (SDL_PollEvent(&engine.event))
        switch (engine.event.type)
        {
            case SDL_KEYDOWN:
                switch (engine.event.key.keysym.sym)
                {
                    case SDLK_ESCAPE:
                        engine.exitFlag = TRUE;
                        break;
                    
                    case SDLK_SPACE:
                        engine.pauseFlag = !engine.pauseFlag;
                        break;

#ifdef DM_DEBUG
                    case SDLK_LEFT:  engineAdjustTime(-500); break;
                    case SDLK_RIGHT: engineAdjustTime( 500); break;
                    case SDLK_UP:    engineAdjustTime( 1000); break;
                    case SDLK_DOWN:  engineAdjustTime(-1000); break;
#endif

                    default:
                        break;
                }

                break;

            case SDL_VIDEOEXPOSE:
                break;

            case SDL_QUIT:
                engine.exitFlag = TRUE;
                break;
        }

        // Draw frame
        frame.startTime = SDL_GetTicks();
        if (engine.pauseFlag != engine.paused)
        {
            engine.paused = engine.pauseFlag;
            engine.pauseTime = engineGetTick();
        }
        
        if (engine.paused)
        {
            engine.startTime = frame.startTime - engine.pauseTime;
        }

        if (SDL_MUSTLOCK(engine.screen) != 0 && SDL_LockSurface(engine.screen) != 0)
        {
            dmError("Can't lock surface.\n");
            goto error_exit;
        }

        // Call main tick
        if ((err = demoMainTick()) != DMERR_OK)
            goto error_exit;

        // Flip screen
        if (SDL_MUSTLOCK(engine.screen) != 0)
            SDL_UnlockSurface(engine.screen);

        SDL_Flip(engine.screen);
        SDL_Delay(20);

        // Get frame time, etc
        frame.endTime = SDL_GetTicks();
        engine.currFrame++;
        engine.totalFrameTime += frame.endTime - frame.startTime;
    }

    // Print benchmark results
    engine.endTime = SDL_GetTicks();
    dmPrint(1, "%d frames in %d ms, fps = %1.3f\n",
        engine.currFrame, engine.endTime - engine.startTime,
        (float) (engine.currFrame * 1000.0f) / (float) engine.totalFrameTime);


error_exit:

    dmPrint(1, "Shutting down.\n");
    SDL_ShowCursor(SDL_ENABLE);
    SDL_PauseAudio(1);

    if (engine.screen)
        SDL_FreeSurface(engine.screen);

    SDL_LockAudio();
    jmpClose(engine.plr);
    jvmClose(engine.dev);
    jssClose();
    SDL_UnlockAudio();

    dmres_close();    

    demoShutdown();

    if (initSDL)
        SDL_Quit();

    demoQuit();
    
    return 0;
}