/*

 * QEMU Proxy for OPL2/3 emulation by MAME team

 *

 * Copyright (c) 2004-2005 Vassili Karpov (malc)

 *

 * Permission is hereby granted, free of charge, to any person obtaining a copy

 * of this software and associated documentation files (the "Software"), to deal

 * in the Software without restriction, including without limitation the rights

 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell

 * copies of the Software, and to permit persons to whom the Software is

 * furnished to do so, subject to the following conditions:

 *

 * The above copyright notice and this permission notice shall be included in

 * all copies or substantial portions of the Software.

 *

 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR

 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,

 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL

 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER

 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,

 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN

 * THE SOFTWARE.

 */

#include <assert.h>

#include "hw.h"

#include "audiodev.h"

#include "audio/audio.h"

#include "isa.h"

//#define DEBUG

#define ADLIB_KILL_TIMERS 1

#ifdef DEBUG

#include "qemu-timer.h"

#endif

#define dolog(...) AUD_log ("adlib", __VA_ARGS__)

#ifdef DEBUG

#define ldebug(...) dolog (__VA_ARGS__)

#else

#define ldebug(...)

#endif

#ifdef HAS_YMF262

#include "ymf262.h"

void YMF262UpdateOneQEMU (int which, INT16 *dst, int length);

#define SHIFT 2

#else

#include "fmopl.h"

#define SHIFT 1

#endif

#define IO_READ_PROTO(name) \

    uint32_t name (void *opaque, uint32_t nport)

#define IO_WRITE_PROTO(name) \

    void name (void *opaque, uint32_t nport, uint32_t val)

static struct {

    int port;

    int freq;

} conf = {0x220, 44100};

typedef struct {

    QEMUSoundCard card;

    int ticking[2];

    int enabled;

    int active;

    int bufpos;

#ifdef DEBUG

    int64_t exp[2];

#endif

    int16_t *mixbuf;

    uint64_t dexp[2];

    SWVoiceOut *voice;

    int left, pos, samples;

    QEMUAudioTimeStamp ats;

#ifndef HAS_YMF262

    FM_OPL *opl;

#endif

} AdlibState;

static AdlibState glob_adlib;

static void adlib_stop_opl_timer (AdlibState *s, size_t n)

{

#ifdef HAS_YMF262

    YMF262TimerOver (0, n);

#else

    OPLTimerOver (s->opl, n);

#endif

    s->ticking[n] = 0;

}

static void adlib_kill_timers (AdlibState *s)

{

    size_t i;

    for (i = 0; i < 2; ++i) {

        if (s->ticking[i]) {

            uint64_t delta;

            delta = AUD_get_elapsed_usec_out (s->voice, &s->ats);

            ldebug (

                "delta = %f dexp = %f expired => %d\n",

                delta / 1000000.0,

                s->dexp[i] / 1000000.0,

                delta >= s->dexp[i]

                );

            if (ADLIB_KILL_TIMERS || delta >= s->dexp[i]) {

                adlib_stop_opl_timer (s, i);

                AUD_init_time_stamp_out (s->voice, &s->ats);

            }

        }

    }

}

static IO_WRITE_PROTO(adlib_write)

{

    AdlibState *s = opaque;

    int a = nport & 3;

    int status;

    s->active = 1;

    AUD_set_active_out (s->voice, 1);

    adlib_kill_timers (s);

#ifdef HAS_YMF262

    status = YMF262Write (0, a, val);

#else

    status = OPLWrite (s->opl, a, val);

#endif

}

static IO_READ_PROTO(adlib_read)

{

    AdlibState *s = opaque;

    uint8_t data;

    int a = nport & 3;

    adlib_kill_timers (s);

#ifdef HAS_YMF262

    data = YMF262Read (0, a);

#else

    data = OPLRead (s->opl, a);

#endif

    return data;

}

static void timer_handler (int c, double interval_Sec)

{

    AdlibState *s = &glob_adlib;

    unsigned n = c & 1;

#ifdef DEBUG

    double interval;

    int64_t exp;

#endif

    if (interval_Sec == 0.0) {

        s->ticking[n] = 0;

        return;

    }

    s->ticking[n] = 1;

#ifdef DEBUG

    interval = ticks_per_sec * interval_Sec;

    exp = qemu_get_clock (vm_clock) + interval;

    s->exp[n] = exp;

#endif

    s->dexp[n] = interval_Sec * 1000000.0;

    AUD_init_time_stamp_out (s->voice, &s->ats);

}

static int write_audio (AdlibState *s, int samples)

{

    int net = 0;

    int pos = s->pos;

    while (samples) {

        int nbytes, wbytes, wsampl;

        nbytes = samples << SHIFT;

        wbytes = AUD_write (

            s->voice,

            s->mixbuf + (pos << (SHIFT - 1)),

            nbytes

            );

        if (wbytes) {

            wsampl = wbytes >> SHIFT;

            samples -= wsampl;

            pos = (pos + wsampl) % s->samples;

            net += wsampl;

        }

        else {

            break;

        }

    }

    return net;

}

static void adlib_callback (void *opaque, int free)

{

    AdlibState *s = opaque;

    int samples, net = 0, to_play, written;

    samples = free >> SHIFT;

    if (!(s->active && s->enabled) || !samples) {

        return;

    }

    to_play = audio_MIN (s->left, samples);

    while (to_play) {

        written = write_audio (s, to_play);

        if (written) {

            s->left -= written;

            samples -= written;

            to_play -= written;

            s->pos = (s->pos + written) % s->samples;

        }

        else {

            return;

        }

    }

    samples = audio_MIN (samples, s->samples - s->pos);

    if (!samples) {

        return;

    }

#ifdef HAS_YMF262

    YMF262UpdateOneQEMU (0, s->mixbuf + s->pos * 2, samples);

#else

    YM3812UpdateOne (s->opl, s->mixbuf + s->pos, samples);

#endif

    while (samples) {

        written = write_audio (s, samples);

        if (written) {

            net += written;

            samples -= written;

            s->pos = (s->pos + written) % s->samples;

        }

        else {

            s->left = samples;

            return;

        }

    }

}

static void Adlib_fini (AdlibState *s)

{

#ifdef HAS_YMF262

    YMF262Shutdown ();

#else

    if (s->opl) {

        OPLDestroy (s->opl);

        s->opl = NULL;

    }

#endif

    if (s->mixbuf) {

        qemu_free (s->mixbuf);

    }

    s->active = 0;

    s->enabled = 0;

    AUD_remove_card (&s->card);

}

int Adlib_init (AudioState *audio, qemu_irq *pic)

{

    AdlibState *s = &glob_adlib;

    struct audsettings as;

    if (!audio) {

        dolog ("No audio state\n");

        return -1;

    }

#ifdef HAS_YMF262

    if (YMF262Init (1, 14318180, conf.freq)) {

        dolog ("YMF262Init %d failed\n", conf.freq);

        return -1;

    }

    else {

        YMF262SetTimerHandler (0, timer_handler, 0);

        s->enabled = 1;

    }

#else

    s->opl = OPLCreate (OPL_TYPE_YM3812, 3579545, conf.freq);

    if (!s->opl) {

        dolog ("OPLCreate %d failed\n", conf.freq);

        return -1;

    }

    else {

        OPLSetTimerHandler (s->opl, timer_handler, 0);

        s->enabled = 1;

    }

#endif

    as.freq = conf.freq;

    as.nchannels = SHIFT;

    as.fmt = AUD_FMT_S16;

    as.endianness = AUDIO_HOST_ENDIANNESS;

    AUD_register_card (audio, "adlib", &s->card);

    s->voice = AUD_open_out (

        &s->card,

        s->voice,

        "adlib",

        s,

        adlib_callback,

        &as

        );

    if (!s->voice) {

        Adlib_fini (s);

        return -1;

    }

    s->samples = AUD_get_buffer_size_out (s->voice) >> SHIFT;

    s->mixbuf = qemu_mallocz (s->samples << SHIFT);

    if (!s->mixbuf) {

        dolog ("Could not allocate mixing buffer, %d samples (each %d bytes)\n",

               s->samples, 1 << SHIFT);

        Adlib_fini (s);

        return -1;

    }

    register_ioport_read (0x388, 4, 1, adlib_read, s);

    register_ioport_write (0x388, 4, 1, adlib_write, s);

    register_ioport_read (conf.port, 4, 1, adlib_read, s);

    register_ioport_write (conf.port, 4, 1, adlib_write, s);

    register_ioport_read (conf.port + 8, 2, 1, adlib_read, s);

    register_ioport_write (conf.port + 8, 2, 1, adlib_write, s);

    return 0;

}