/*

    SDL - Simple DirectMedia Layer

    Copyright (C) 1997-2006 Sam Lantinga

    This library is free software; you can redistribute it and/or

    modify it under the terms of the GNU Lesser General Public

    License as published by the Free Software Foundation; either

    version 2.1 of the License, or (at your option) any later version.

    This library 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

    Lesser General Public License for more details.

    You should have received a copy of the GNU Lesser General Public

    License along with this library; if not, write to the Free Software

    Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA

    Sam Lantinga

    slouken@libsdl.org

*/

#include "SDL_config.h"

/* Allow access to a raw mixing buffer */

#include "SDL.h"

#include "SDL_audio_c.h"

#include "SDL_audiomem.h"

#include "SDL_sysaudio.h"

#ifdef __OS2__

/* We'll need the DosSetPriority() API! */

#define INCL_DOSPROCESS

#include <os2.h>

#endif

/* Available audio drivers */

static AudioBootStrap *bootstrap[] = {

#if SDL_AUDIO_DRIVER_BSD

    &BSD_AUDIO_bootstrap,

#endif

#if SDL_AUDIO_DRIVER_OSS

    &DSP_bootstrap,

    &DMA_bootstrap,

#endif

#if SDL_AUDIO_DRIVER_ALSA

    &ALSA_bootstrap,

#endif

#if SDL_AUDIO_DRIVER_QNXNTO

    &QNXNTOAUDIO_bootstrap,

#endif

#if SDL_AUDIO_DRIVER_SUNAUDIO

    &SUNAUDIO_bootstrap,

#endif

#if SDL_AUDIO_DRIVER_DMEDIA

    &DMEDIA_bootstrap,

#endif

#if SDL_AUDIO_DRIVER_ARTS

    &ARTS_bootstrap,

#endif

#if SDL_AUDIO_DRIVER_ESD

    &ESD_bootstrap,

#endif

#if SDL_AUDIO_DRIVER_NAS

    &NAS_bootstrap,

#endif

#if SDL_AUDIO_DRIVER_DSOUND

    &DSOUND_bootstrap,

#endif

#if SDL_AUDIO_DRIVER_WAVEOUT

    &WAVEOUT_bootstrap,

#endif

#if SDL_AUDIO_DRIVER_PAUD

    &Paud_bootstrap,

#endif

#if SDL_AUDIO_DRIVER_BAUDIO

    &BAUDIO_bootstrap,

#endif

#if SDL_AUDIO_DRIVER_COREAUDIO

    &COREAUDIO_bootstrap,

#endif

#if SDL_AUDIO_DRIVER_SNDMGR

    &SNDMGR_bootstrap,

#endif

#if SDL_AUDIO_DRIVER_AHI

    &AHI_bootstrap,

#endif

#if SDL_AUDIO_DRIVER_MINT

    &MINTAUDIO_GSXB_bootstrap,

    &MINTAUDIO_MCSN_bootstrap,

    &MINTAUDIO_STFA_bootstrap,

    &MINTAUDIO_XBIOS_bootstrap,

    &MINTAUDIO_DMA8_bootstrap,

#endif

#if SDL_AUDIO_DRIVER_DISK

    &DISKAUD_bootstrap,

#endif

#if SDL_AUDIO_DRIVER_DUMMY

    &DUMMYAUD_bootstrap,

#endif

#if SDL_AUDIO_DRIVER_DC

    &DCAUD_bootstrap,

#endif

#if SDL_AUDIO_DRIVER_MMEAUDIO

    &MMEAUDIO_bootstrap,

#endif

#if SDL_AUDIO_DRIVER_DART

    &DART_bootstrap,

#endif

    NULL

};

SDL_AudioDevice *current_audio = NULL;

/* Various local functions */

int SDL_AudioInit(const char *driver_name);

void SDL_AudioQuit(void);

#if SDL_AUDIO_DRIVER_AHI

static int audio_configured = 0;

#endif

/* The general mixing thread function */

int SDLCALL

SDL_RunAudio(void *audiop)

{

    SDL_AudioDevice *audio = (SDL_AudioDevice *) audiop;

    Uint8 *stream;

    int stream_len;

    void *udata;

    void (SDLCALL * fill) (void *userdata, Uint8 * stream, int len);

    int silence;

#if SDL_AUDIO_DRIVER_AHI

    int started = 0;

/* AmigaOS NEEDS that the audio driver is opened in the thread that uses it! */

    D(bug("Task audio started audio struct:<%lx>...\n", audiop));

    D(bug("Before Openaudio..."));

    if (audio->OpenAudio(audio, &audio->spec) == -1) {

        D(bug("Open audio failed...\n"));

        return (-1);

    }

    D(bug("OpenAudio...OK\n"));

#endif

    /* Perform any thread setup */

    if (audio->ThreadInit) {

        audio->ThreadInit(audio);

    }

    audio->threadid = SDL_ThreadID();

    /* Set up the mixing function */

    fill = audio->spec.callback;

    udata = audio->spec.userdata;

#if SDL_AUDIO_DRIVER_AHI

    audio_configured = 1;

    D(bug("Audio configured... Checking for conversion\n"));

    SDL_mutexP(audio->mixer_lock);

    D(bug("Semaphore obtained...\n"));

#endif

    if (audio->convert.needed) {

        if (audio->convert.src_format == AUDIO_U8) {

            silence = 0x80;

        } else {

            silence = 0;

        }

        stream_len = audio->convert.len;

    } else {

        silence = audio->spec.silence;

        stream_len = audio->spec.size;

    }

#if SDL_AUDIO_DRIVER_AHI

    SDL_mutexV(audio->mixer_lock);

    D(bug("Entering audio loop...\n"));

#endif

#ifdef __OS2__

    /* Increase the priority of this thread to make sure that

       the audio will be continuous all the time! */

#ifdef USE_DOSSETPRIORITY

    if (SDL_getenv("SDL_USE_TIMECRITICAL_AUDIO")) {

#ifdef DEBUG_BUILD

        printf

            ("[SDL_RunAudio] : Setting priority to TimeCritical+0! (TID%d)\n",

             SDL_ThreadID());

#endif

        DosSetPriority(PRTYS_THREAD, PRTYC_TIMECRITICAL, 0, 0);

    } else {

#ifdef DEBUG_BUILD

        printf

            ("[SDL_RunAudio] : Setting priority to ForegroundServer+0! (TID%d)\n",

             SDL_ThreadID());

#endif

        DosSetPriority(PRTYS_THREAD, PRTYC_FOREGROUNDSERVER, 0, 0);

    }

#endif

#endif

    /* Loop, filling the audio buffers */

    while (audio->enabled) {

        /* Fill the current buffer with sound */

        if (audio->convert.needed) {

            if (audio->convert.buf) {

                stream = audio->convert.buf;

            } else {

                continue;

            }

        } else {

            stream = audio->GetAudioBuf(audio);

            if (stream == NULL) {

                stream = audio->fake_stream;

            }

        }

        SDL_memset(stream, silence, stream_len);

        if (!audio->paused) {

            SDL_mutexP(audio->mixer_lock);

            (*fill) (udata, stream, stream_len);

            SDL_mutexV(audio->mixer_lock);

        }

        /* Convert the audio if necessary */

        if (audio->convert.needed) {

            SDL_ConvertAudio(&audio->convert);

            stream = audio->GetAudioBuf(audio);

            if (stream == NULL) {

                stream = audio->fake_stream;

            }

            SDL_memcpy(stream, audio->convert.buf, audio->convert.len_cvt);

        }

        /* Ready current buffer for play and change current buffer */

        if (stream != audio->fake_stream) {

            audio->PlayAudio(audio);

        }

        /* Wait for an audio buffer to become available */

        if (stream == audio->fake_stream) {

            SDL_Delay((audio->spec.samples * 1000) / audio->spec.freq);

        } else {

            audio->WaitAudio(audio);

        }

    }

    /* Wait for the audio to drain.. */

    if (audio->WaitDone) {

        audio->WaitDone(audio);

    }

#if SDL_AUDIO_DRIVER_AHI

    D(bug("WaitAudio...Done\n"));

    audio->CloseAudio(audio);

    D(bug("CloseAudio..Done, subtask exiting...\n"));

    audio_configured = 0;

#endif

#ifdef __OS2__

#ifdef DEBUG_BUILD

    printf("[SDL_RunAudio] : Task exiting. (TID%d)\n", SDL_ThreadID());

#endif

#endif

    return (0);

}

static void

SDL_LockAudio_Default(SDL_AudioDevice * audio)

{

    if (audio->thread && (SDL_ThreadID() == audio->threadid)) {

        return;

    }

    SDL_mutexP(audio->mixer_lock);

}

static void

SDL_UnlockAudio_Default(SDL_AudioDevice * audio)

{

    if (audio->thread && (SDL_ThreadID() == audio->threadid)) {

        return;

    }

    SDL_mutexV(audio->mixer_lock);

}

static Uint16

SDL_ParseAudioFormat(const char *string)

{

    Uint16 format = 0;

    switch (*string) {

    case 'U':

        ++string;

        format |= 0x0000;

        break;

    case 'S':

        ++string;

        format |= 0x8000;

        break;

    default:

        return 0;

    }

    switch (SDL_atoi(string)) {

    case 8:

        string += 1;

        format |= 8;

        break;

    case 16:

        string += 2;

        format |= 16;

        if (SDL_strcmp(string, "LSB") == 0

#if SDL_BYTEORDER == SDL_LIL_ENDIAN

            || SDL_strcmp(string, "SYS") == 0

#endif

            ) {

            format |= 0x0000;

        }

        if (SDL_strcmp(string, "MSB") == 0

#if SDL_BYTEORDER == SDL_BIG_ENDIAN

            || SDL_strcmp(string, "SYS") == 0

#endif

            ) {

            format |= 0x1000;

        }

        break;

    default:

        return 0;

    }

    return format;

}

int

SDL_GetNumAudioDrivers(void)

{

    return (SDL_arraysize(bootstrap) - 1);

}

const char *

SDL_GetAudioDriver(int index)

{

    if (index >= 0 && index < SDL_GetNumAudioDrivers()) {

        return (bootstrap[index]->name);

    }

    return (NULL);

}

int

SDL_AudioInit(const char *driver_name)

{

    SDL_AudioDevice *audio;

    int i = 0, idx;

    /* Check to make sure we don't overwrite 'current_audio' */

    if (current_audio != NULL) {

        SDL_AudioQuit();

    }

    /* Select the proper audio driver */

    audio = NULL;

    idx = 0;

    if (driver_name == NULL) {

        driver_name = SDL_getenv("SDL_AUDIODRIVER");

    }

#if SDL_AUDIO_DRIVER_ESD

    if ((driver_name == NULL) && (SDL_getenv("ESPEAKER") != NULL)) {

        /* Ahem, we know that if ESPEAKER is set, user probably wants

           to use ESD, but don't start it if it's not already running.

           This probably isn't the place to do this, but... Shh! :)

         */

        for (i = 0; bootstrap[i]; ++i) {

            if (SDL_strcmp(bootstrap[i]->name, "esd") == 0) {

#ifdef HAVE_PUTENV

                const char *esd_no_spawn;

                /* Don't start ESD if it's not running */

                esd_no_spawn = getenv("ESD_NO_SPAWN");

                if (esd_no_spawn == NULL) {

                    putenv("ESD_NO_SPAWN=1");

                }

#endif

                if (bootstrap[i]->available()) {

                    audio = bootstrap[i]->create(0);

                    break;

                }

#ifdef HAVE_UNSETENV

                if (esd_no_spawn == NULL) {

                    unsetenv("ESD_NO_SPAWN");

                }

#endif

            }

        }

    }

#endif /* SDL_AUDIO_DRIVER_ESD */

    if (audio == NULL) {

        if (driver_name != NULL) {

            for (i = 0; bootstrap[i]; ++i) {

                if (SDL_strncmp(bootstrap[i]->name, driver_name,

                                SDL_strlen(bootstrap[i]->name)) == 0) {

                    if (bootstrap[i]->available()) {

                        audio = bootstrap[i]->create(idx);

                    }

                    break;

                }

            }

        } else {

            for (i = 0; bootstrap[i]; ++i) {

                if (bootstrap[i]->available()) {

                    audio = bootstrap[i]->create(idx);

                    if (audio != NULL) {

                        break;

                    }

                }

            }

        }

        if (audio == NULL) {

            if (driver_name) {

                SDL_SetError("%s not available", driver_name);

            } else {

                SDL_SetError("No available audio device");

            }

#if 0

            /* Don't fail SDL_Init() if audio isn't available.

               SDL_OpenAudio() will handle it at that point.  *sigh*

             */

            return (-1);

#endif

        }

    }

    current_audio = audio;

    if (current_audio) {

        current_audio->name = bootstrap[i]->name;

        if (!current_audio->LockAudio && !current_audio->UnlockAudio) {

            current_audio->LockAudio = SDL_LockAudio_Default;

            current_audio->UnlockAudio = SDL_UnlockAudio_Default;

        }

    }

    return (0);

}

/*

 * Get the current audio driver name

 */

const char *

SDL_GetCurrentAudioDriver()

{

    if (current_audio) {

        return current_audio->name;

    }

    return (NULL);

}

int

SDL_OpenAudio(SDL_AudioSpec * desired, SDL_AudioSpec * obtained)

{

    SDL_AudioDevice *audio;

    const char *env;

    /* Start up the audio driver, if necessary */

    if (!current_audio) {

        if ((SDL_InitSubSystem(SDL_INIT_AUDIO) < 0) ||

            (current_audio == NULL)) {

            return (-1);

        }

    }

    audio = current_audio;

    if (audio->opened) {

        SDL_SetError("Audio device is already opened");

        return (-1);

    }

    /* Verify some parameters */

    if (desired->freq == 0) {

        env = SDL_getenv("SDL_AUDIO_FREQUENCY");

        if (env) {

            desired->freq = SDL_atoi(env);

        }

    }

    if (desired->freq == 0) {

        /* Pick some default audio frequency */

        desired->freq = 22050;

    }

    if (desired->format == 0) {

        env = SDL_getenv("SDL_AUDIO_FORMAT");

        if (env) {

            desired->format = SDL_ParseAudioFormat(env);

        }

    }

    if (desired->format == 0) {

        /* Pick some default audio format */

        desired->format = AUDIO_S16;

    }

    if (desired->channels == 0) {

        env = SDL_getenv("SDL_AUDIO_CHANNELS");

        if (env) {

            desired->channels = (Uint8) SDL_atoi(env);

        }

    }

    if (desired->channels == 0) {

        /* Pick a default number of channels */

        desired->channels = 2;

    }

    switch (desired->channels) {

    case 1:                    /* Mono */

    case 2:                    /* Stereo */

    case 4:                    /* surround */

    case 6:                    /* surround with center and lfe */

        break;

    default:

        SDL_SetError("1 (mono) and 2 (stereo) channels supported");

        return (-1);

    }

    if (desired->samples == 0) {

        env = SDL_getenv("SDL_AUDIO_SAMPLES");

        if (env) {

            desired->samples = (Uint16) SDL_atoi(env);

        }

    }

    if (desired->samples == 0) {

        /* Pick a default of ~46 ms at desired frequency */

        int samples = (desired->freq / 1000) * 46;

        int power2 = 1;

        while (power2 < samples) {

            power2 *= 2;

        }

        desired->samples = power2;

    }

    if (desired->callback == NULL) {

        SDL_SetError("SDL_OpenAudio() passed a NULL callback");

        return (-1);

    }

#if defined(__MACOS__) || (defined(__RISCOS__) && SDL_THREADS_DISABLED)

    /* FIXME: Need to implement PPC interrupt asm for SDL_LockAudio() */

#else

#if defined(__MINT__) && SDL_THREADS_DISABLED

    /* Uses interrupt driven audio, without thread */

#else

    /* Create a semaphore for locking the sound buffers */

    audio->mixer_lock = SDL_CreateMutex();

    if (audio->mixer_lock == NULL) {

        SDL_SetError("Couldn't create mixer lock");

        SDL_CloseAudio();

        return (-1);

    }

#endif /* __MINT__ */

#endif /* __MACOS__ */

    /* Calculate the silence and size of the audio specification */

    SDL_CalculateAudioSpec(desired);

    /* Open the audio subsystem */

    SDL_memcpy(&audio->spec, desired, sizeof(audio->spec));

    audio->convert.needed = 0;

    audio->enabled = 1;

    audio->paused = 1;

#if !SDL_AUDIO_DRIVER_AHI

/* AmigaOS opens audio inside the main loop */

    audio->opened = audio->OpenAudio(audio, &audio->spec) + 1;

    if (!audio->opened) {

        SDL_CloseAudio();

        return (-1);

    }

#else

    D(bug("Locking semaphore..."));

    SDL_mutexP(audio->mixer_lock);

    audio->thread = SDL_CreateThread(SDL_RunAudio, audio);

    D(bug("Created thread...\n"));

    if (audio->thread == NULL) {

        SDL_mutexV(audio->mixer_lock);

        SDL_CloseAudio();

        SDL_SetError("Couldn't create audio thread");

        return (-1);

    }

    while (!audio_configured)

        SDL_Delay(100);

#endif

    /* If the audio driver changes the buffer size, accept it */

    if (audio->spec.samples != desired->samples) {

        desired->samples = audio->spec.samples;

        SDL_CalculateAudioSpec(desired);

    }

    /* Allocate a fake audio memory buffer */

    audio->fake_stream = SDL_AllocAudioMem(audio->spec.size);

    if (audio->fake_stream == NULL) {

        SDL_CloseAudio();

        SDL_OutOfMemory();

        return (-1);

    }

    /* See if we need to do any conversion */

    if (obtained != NULL) {

        SDL_memcpy(obtained, &audio->spec, sizeof(audio->spec));

    } else if (desired->freq != audio->spec.freq ||

               desired->format != audio->spec.format ||

               desired->channels != audio->spec.channels) {

        /* Build an audio conversion block */

        if (SDL_BuildAudioCVT(&audio->convert,

                              desired->format, desired->channels,

                              desired->freq,

                              audio->spec.format, audio->spec.channels,

                              audio->spec.freq) < 0) {

            SDL_CloseAudio();

            return (-1);

        }

        if (audio->convert.needed) {

            audio->convert.len = desired->size;

            audio->convert.buf =

                (Uint8 *) SDL_AllocAudioMem(audio->convert.len *

                                            audio->convert.len_mult);

            if (audio->convert.buf == NULL) {

                SDL_CloseAudio();

                SDL_OutOfMemory();

                return (-1);

            }

        }

    }

#if !SDL_AUDIO_DRIVER_AHI

    /* Start the audio thread if necessary */

    switch (audio->opened) {

    case 1:

        /* Start the audio thread */

#if (defined(__WIN32__) && !defined(_WIN32_WCE)) && !defined(HAVE_LIBC)

#undef SDL_CreateThread

        audio->thread = SDL_CreateThread(SDL_RunAudio, audio, NULL, NULL);

#else

        audio->thread = SDL_CreateThread(SDL_RunAudio, audio);

#endif

        if (audio->thread == NULL) {

            SDL_CloseAudio();

            SDL_SetError("Couldn't create audio thread");

            return (-1);

        }

        break;

    default:

        /* The audio is now playing */

        break;

    }

#else

    SDL_mutexV(audio->mixer_lock);

    D(bug("SDL_OpenAudio USCITA...\n"));

#endif

    return (0);

}

SDL_audiostatus

SDL_GetAudioStatus(void)

{

    SDL_AudioDevice *audio = current_audio;

    SDL_audiostatus status;

    status = SDL_AUDIO_STOPPED;

    if (audio && audio->enabled) {

        if (audio->paused) {

            status = SDL_AUDIO_PAUSED;

        } else {

            status = SDL_AUDIO_PLAYING;

        }

    }

    return (status);

}

void

SDL_PauseAudio(int pause_on)

{

    SDL_AudioDevice *audio = current_audio;

    if (audio) {

        audio->paused = pause_on;

    }

}

void

SDL_LockAudio(void)

{

    SDL_AudioDevice *audio = current_audio;

    /* Obtain a lock on the mixing buffers */

    if (audio && audio->LockAudio) {

        audio->LockAudio(audio);

    }

}

void

SDL_UnlockAudio(void)

{

    SDL_AudioDevice *audio = current_audio;

    /* Release lock on the mixing buffers */

    if (audio && audio->UnlockAudio) {

        audio->UnlockAudio(audio);

    }

}

void

SDL_CloseAudio(void)

{

    SDL_QuitSubSystem(SDL_INIT_AUDIO);

}

void

SDL_AudioQuit(void)

{

    SDL_AudioDevice *audio = current_audio;

    if (audio) {

        audio->enabled = 0;

        if (audio->thread != NULL) {

            SDL_WaitThread(audio->thread, NULL);

        }

        if (audio->mixer_lock != NULL) {

            SDL_DestroyMutex(audio->mixer_lock);

        }

        if (audio->fake_stream != NULL) {

            SDL_FreeAudioMem(audio->fake_stream);

        }

        if (audio->convert.needed) {

            SDL_FreeAudioMem(audio->convert.buf);

        }

#if !SDL_AUDIO_DRIVER_AHI

        if (audio->opened) {

            audio->CloseAudio(audio);

            audio->opened = 0;

        }

#endif

        /* Free the driver data */

        audio->free(audio);

        current_audio = NULL;

    }

}

#define NUM_FORMATS	6

static int format_idx;

static int format_idx_sub;

static Uint16 format_list[NUM_FORMATS][NUM_FORMATS] = {

    {AUDIO_U8, AUDIO_S8, AUDIO_S16LSB, AUDIO_S16MSB, AUDIO_U16LSB,

     AUDIO_U16MSB},

    {AUDIO_S8, AUDIO_U8, AUDIO_S16LSB, AUDIO_S16MSB, AUDIO_U16LSB,

     AUDIO_U16MSB},

    {AUDIO_S16LSB, AUDIO_S16MSB, AUDIO_U16LSB, AUDIO_U16MSB, AUDIO_U8,

     AUDIO_S8},

    {AUDIO_S16MSB, AUDIO_S16LSB, AUDIO_U16MSB, AUDIO_U16LSB, AUDIO_U8,

     AUDIO_S8},

    {AUDIO_U16LSB, AUDIO_U16MSB, AUDIO_S16LSB, AUDIO_S16MSB, AUDIO_U8,

     AUDIO_S8},

    {AUDIO_U16MSB, AUDIO_U16LSB, AUDIO_S16MSB, AUDIO_S16LSB, AUDIO_U8,

     AUDIO_S8},

};

Uint16

SDL_FirstAudioFormat(Uint16 format)

{

    for (format_idx = 0; format_idx < NUM_FORMATS; ++format_idx) {

        if (format_list[format_idx][0] == format) {

            break;

        }

    }

    format_idx_sub = 0;

    return (SDL_NextAudioFormat());

}

Uint16

SDL_NextAudioFormat(void)

{

    if ((format_idx == NUM_FORMATS) || (format_idx_sub == NUM_FORMATS)) {

        return (0);

    }

    return (format_list[format_idx][format_idx_sub++]);

}

void

SDL_CalculateAudioSpec(SDL_AudioSpec * spec)

{

    switch (spec->format) {

    case AUDIO_U8:

        spec->silence = 0x80;

        break;

    default:

        spec->silence = 0x00;

        break;

    }

    spec->size = (spec->format & 0xFF) / 8;

    spec->size *= spec->channels;

    spec->size *= spec->samples;

}

/* vi: set ts=4 sw=4 expandtab: */