/*
 * mididrv.c - MIDI emulation for win32.
 *
 * Written by
 *  Daniel Kahlin <daniel@kahlin.net>
 *
 * This file is part of VICE, the Versatile Commodore Emulator.
 * See README for copyright notice.
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  This program 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 General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
 *  02111-1307  USA.
 *
 */

#undef DEBUG

#include "vice.h"

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <windows.h>
#include <mmsystem.h>

#include "cmdline.h"
#include "log.h"
#include "mididrv.h"

#ifndef USE_SDLUI
#include "res.h"
#endif

#include "resources.h"
#include "translate.h"
#include "types.h"

/* ------------------------------------------------------------------------- */

static log_t mididrv_log = LOG_ERR;

static HMIDIIN handle_in = 0;
static HMIDIOUT handle_out = 0;

static void CALLBACK midi_callback(HMIDIIN handle, UINT uMsg, DWORD dwInstance, DWORD dwParam1, DWORD dwParam2);

/* ------------------------------------------------------------------------- */

#define OUT_BUF_LEN 3

static int out_index = 0;
static BYTE out_buf[OUT_BUF_LEN];

/* ------------------------------------------------------------------------- */

#define IN_BUF_LEN 1024

static volatile unsigned int in_wi = 0;
static volatile unsigned int in_ri = 0;
static BYTE in_buf[IN_BUF_LEN];

static int midi_in_dev = 0;
static int midi_out_dev = 0;

static int set_midi_in_dev(int val, void *param)
{
    midi_in_dev = val;
    return 0;
}

static int set_midi_out_dev(int val, void *param)
{
    midi_out_dev = val;
    return 0;
}

static const resource_int_t resources_int[] = {
    { "MIDIInDev", 0, RES_EVENT_NO, (resource_value_t)0,
      &midi_in_dev, set_midi_in_dev, NULL },
    { "MIDIOutDev", 0, RES_EVENT_NO, (resource_value_t)0,
      &midi_out_dev, set_midi_out_dev, NULL },
    { NULL }
};

int mididrv_resources_init(void)
{
    return resources_register_int(resources_int);
}

void mididrv_resources_shutdown(void)
{
}

static const cmdline_option_t cmdline_options[] = {
    { "-midiin", SET_RESOURCE, 1,
      NULL, NULL, "MIDIInDev", NULL,
#ifndef USE_SDLUI
      USE_PARAM_ID, USE_DESCRIPTION_ID,
      IDS_P_NUMBER, IDS_SPECIFY_MIDI_IN,
#else
      USE_PARAM_STRING, USE_DESCRIPTION_STRING,
      0, 0,
#endif
      "<number>", "Specify MIDI-In device" },
    { "-midiout", SET_RESOURCE, 1,
      NULL, NULL, "MIDIOutDev", NULL,
#ifndef USE_SDLUI
      USE_PARAM_ID, USE_DESCRIPTION_ID,
      IDS_P_NUMBER, IDS_SPECIFY_MIDI_OUT,
#else
      USE_PARAM_STRING, USE_DESCRIPTION_STRING,
      0, 0,
#endif
      "<number>", "Specify MIDI-Out device" },
    { NULL }
};

int mididrv_cmdline_options_init(void)
{
    return cmdline_register_options(cmdline_options);
}

static void reset_fifo(void)
{
    in_wi=0;
    in_ri=0;
}

static int write_fifo(BYTE data)
{
    if (((in_wi - in_ri) % IN_BUF_LEN) == (IN_BUF_LEN - 1)) {
        return 1;
    }

    in_buf[in_wi] = data;
    in_wi = (in_wi + 1) % IN_BUF_LEN;
    return 0;
}

static int read_fifo(BYTE *data)
{
    if (((in_wi - in_ri) % IN_BUF_LEN) != 0) {
        *data = in_buf[in_ri];
        in_ri = (in_ri + 1) % IN_BUF_LEN;
        return 1;
    }
    return 0;
}

/* ------------------------------------------------------------------------- */

static int message_len(BYTE msg)
{
    int len = 0;

    switch (msg & 0xf0) {
        case 0x80: /* Note Off */
        case 0x90: /* Note On */
        case 0xa0: /* Polyphonic Aftertouch */
        case 0xb0: /* Control Change */
        case 0xe0: /* Pitch Wheel */
            len = 3;
            break;
        case 0xc0: /* Program Change */
        case 0xd0: /* Channel Aftertouch */
            len = 2;
            break;
        case 0xf0: /* Special */
            switch (msg) {
                case 0xf0: /* Sysex Start (shouldn't happen here) */
                case 0xf7: /* Sysex End (shouldn't happen here) */
                    len = -1;
                    break;
                case 0xf2: /* Song Pointer */
                    len = 3;
                    break;
                case 0xf1: /* Quarter Frame */
                case 0xf3: /* Song Select */
                case 0xf9: /* Measure End */
                    len = 2;
                    break;
                case 0xf6: /* Tuning Request */
                case 0xf8: /* Timing Clock */
                case 0xfa: /* Start */
                case 0xfb: /* Continue */
                case 0xfc: /* Stop */
                case 0xfe: /* Active Sensing */
                case 0xff: /* Reset */
                    len = 1;
                    break;
                default:
                    break;
            }
        default: /* running status */
            len = 2;
            break;
    }
    return len;
}

/* ------------------------------------------------------------------------- */

void mididrv_init(void)
{
    if (mididrv_log == LOG_ERR) {
        mididrv_log = log_open("MIDIdrv");
    }
}

/* opens a MIDI-In device, returns handle */
int mididrv_in_open(void)
{
    MMRESULT ret;

    log_message(mididrv_log, "Opening MIDI-In device #%d", midi_in_dev);
    if (handle_in) {
        mididrv_in_close();
    }

    ret = midiInOpen(&handle_in, midi_in_dev, (DWORD)midi_callback, 0, CALLBACK_FUNCTION);
    if (ret != MMSYSERR_NOERROR) {
        log_error(mididrv_log, "Cannot open MIDI-In device #%d!", midi_in_dev);
        handle_in = 0;
        return -1;
    }

    /* reset FIFO */
    reset_fifo();

    /* can theoretically return MMSYSERR_INVALHANDLE */
    ret = midiInStart(handle_in);

    return (DWORD)handle_in;
}

/* opens a MIDI-Out device, returns handle */
int mididrv_out_open(void)
{
    MMRESULT ret;

    log_message(mididrv_log, "Opening MIDI-Out device #%d", midi_out_dev);
    if (handle_out) {
        mididrv_out_close();
    }

    ret = midiOutOpen(&handle_out, midi_out_dev, 0, 0, CALLBACK_NULL);
    if (ret != MMSYSERR_NOERROR) {
        log_error(mididrv_log, "Cannot open MIDI-Out device #%d!", midi_out_dev);
        handle_out = 0;
        return -1;
    }

    /* reset buffer */
    out_index = 0;

    return (DWORD)handle_out;
}

/* closes the MIDI-In device*/
void mididrv_in_close(void)
{
    MMRESULT ret;
#ifdef DEBUG
    log_message(mididrv_log, "in_close");
#endif
    if (!handle_in) {
        log_error(mididrv_log, "Attempt to close MIDI-In device that wasn't open!");
        return;
    }
    /* can theoretically return MMSYSERR_INVALHANDLE */
    ret = midiInReset(handle_in);

    ret = midiInClose(handle_in);
    if (ret != MMSYSERR_NOERROR) {
        log_error(mididrv_log, "Couldn't close MIDI-In device.");
    }
    handle_in = 0;
}

/* closes the MIDI-Out device*/
void mididrv_out_close(void)
{
    MMRESULT ret;
#ifdef DEBUG
    log_message(mididrv_log, "out_close");
#endif
    if (!handle_out) {
        log_error(mididrv_log, "Attempt to close MIDI-Out device that wasn't open!");
        return;
    }

    /* can theoretically return MMSYSERR_INVALHANDLE */
    ret = midiOutReset(handle_out);

    ret = midiOutClose(handle_out);
    if (ret != MMSYSERR_NOERROR) {
        log_error(mididrv_log, "Couldn't close MIDI-Out device.");
    }
    handle_out = 0;
}

/* sends a byte to MIDI-Out */
void mididrv_out(BYTE b)
{
    MMRESULT ret;
    int thres;

#ifdef DEBUG
    log_message(mididrv_log, "out %02x", b);
#endif

    out_buf[out_index] = b;
    out_index++;
    if (out_index >= OUT_BUF_LEN) {
        out_index = 0;
        log_error(mididrv_log, "MIDI-Out overrun.");
    }

    thres = message_len(out_buf[0]);

    /* flush when enough bytes have been queued */
    if (out_index >= thres) {
        DWORD data;

        out_index = 0;
        data = out_buf[0] | (out_buf[1] << 8) | (out_buf[2] << 16);
#ifdef DEBUG
        log_message(mididrv_log, "flushing out %06x", data);
#endif
        ret = midiOutShortMsg(handle_out, data);
        if (ret != MMSYSERR_NOERROR) {
            log_error(mididrv_log, "Failed to output data on MIDI-Out device.");
        }
    }

    return;
}

static void CALLBACK midi_callback(HMIDIIN handle, UINT uMsg, DWORD dwInstance, DWORD dwParam1, DWORD dwParam2)
{
    int len;
    int i;
    switch (uMsg) {
        case MIM_DATA:
#ifdef DEBUG
            log_message(mididrv_log, "MIDI callback got %08x", dwParam1);
#endif
            len = message_len((BYTE)(dwParam1 & 0xff));
            for (i = 0; i < len; i++) {
                write_fifo((BYTE)(dwParam1 & 0xff));
                dwParam1 >>= 8;
            }
            break;
        case MIM_LONGDATA:
            break;
        case MIM_OPEN:
        case MIM_CLOSE:
        case MIM_ERROR:
        case MIM_LONGERROR:
        case MIM_MOREDATA:
            break;
        default:
            break;
    }
}


/* gets a byte from MIDI-In, returns !=0 if byte received, byte in *b. */
int mididrv_in(BYTE *b)
{
    if (!handle_in) {
        log_error(mididrv_log, "Attempt to read from closed MIDI-In port!");
        return -1;
    }

    if (read_fifo(b)) {
#ifdef DEBUG
        log_message(mididrv_log, "in got %02x", *b);
#endif
        return 1;
    }
    return 0;
}
