/*
 * Schism Tracker - a cross-platform Impulse Tracker clone
 * copyright (c) 2003-2005 Storlek <storlek@rigelseven.com>
 * copyright (c) 2005-2008 Mrs. Brisby <mrs.brisby@nimh.org>
 * copyright (c) 2009 Storlek & Mrs. Brisby
 * copyright (c) 2010-2012 Storlek
 * URL: http://schismtracker.org/
 *
 * 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
 */


#include "headers.h"

#include "midi.h"

#include "util.h"

#ifdef USE_OSS

#include <sys/types.h>
#include <sys/stat.h>
#include <sys/ioctl.h>
#include <sys/soundcard.h>
#include <sys/poll.h>

#include <errno.h>
#include <fcntl.h>

/* this is stupid; oss doesn't have a concept of ports... */
#define MAX_OSS_MIDI    64

#define MAX_MIDI_PORTS  MAX_OSS_MIDI+2
static int opened[MAX_MIDI_PORTS];


static void _oss_send(struct midi_port *p, const unsigned char *data, unsigned int len,
        UNUSED unsigned int delay)
{
        int fd, r, n;
        fd = opened[ n = INT_SHAPED_PTR(p->userdata) ];
        if (fd < 0) return;
        while (len > 0) {
                r = write(fd, data, len);
                if (r < -1 && errno == EINTR) continue;
                if (r < 1) {
                        /* err, can't happen? */
                        (void)close(opened[n]);
                        opened[n] = -1;
                        p->userdata = PTR_SHAPED_INT(-1);
                        p->io = 0; /* failure! */
                        return;
                }
                data += r;
                len -= r;
        }
}

static int _oss_start(UNUSED struct midi_port *p) { return 1; /* do nothing */ }
static int _oss_stop(UNUSED struct midi_port *p) { return 1; /* do nothing */ }


static int _oss_thread(struct midi_provider *p)
{
        struct pollfd pfd[MAX_MIDI_PORTS];
        struct midi_port *ptr, *src;
        unsigned char midi_buf[4096];
        int i, j, r;

        for (;;) {
                ptr = NULL;
                j = 0;
                while (midi_port_foreach(p, &ptr)) {
                        i = INT_SHAPED_PTR(ptr->userdata);
                        if (i == -1) continue; /* err... */
                        if (!(ptr->io & MIDI_INPUT)) continue;
                        pfd[j].fd = i;
                        pfd[j].events = POLLIN;
                        pfd[j].revents = 0; /* RH 5 bug */
                        j++;
                }
                if (!j || poll(pfd, j, -1) < 1) {
                        sleep(1);
                        continue;
                }
                for (i = 0; i < j; i++) {
                        if (!(pfd[i].revents & POLLIN)) continue;
                        do {
                                r = read(pfd[i].fd, midi_buf, sizeof(midi_buf));
                        } while (r == -1 && errno == EINTR);
                        if (r > 0) {
                                ptr = src = NULL;
                                while (midi_port_foreach(p, &ptr)) {
                                        if (INT_SHAPED_PTR(ptr->userdata) == pfd[i].fd) {
                                                src = ptr;
                                        }
                                }
                                midi_received_cb(src, midi_buf, r);
                        }
                }
        }
        /* stupid gcc */
        return 0;
}


static void _tryopen(int n, const char *name, struct midi_provider *_oss_provider)
{
        int io;
        char *ptr;

        if (opened[n+1] != -1) return;
        opened[n+1] = open(name, O_RDWR|O_NOCTTY|O_NONBLOCK);
        if (opened[n+1] == -1) {
                opened[n+1] = open(name, O_RDONLY|O_NOCTTY|O_NONBLOCK);
                if (opened[n+1] == -1) {
                        opened[n+1] = open(name, O_WRONLY|O_NOCTTY|O_NONBLOCK);
                        if (opened[n+1] == -1) return;
                        io = MIDI_OUTPUT;
                } else {
                        io = MIDI_INPUT;
                }
        } else {
                io = MIDI_INPUT | MIDI_OUTPUT;
        }

        ptr = NULL;
        if (asprintf(&ptr, " %-16s (OSS)", name) == -1) {
                return;
        }
        midi_port_register(_oss_provider, io, ptr, PTR_SHAPED_INT((long)n+1), 0);
        free(ptr);
}

static void _oss_poll(struct midi_provider *_oss_provider)
{
        char sbuf[64];
        int i;

        _tryopen(-1, "/dev/midi", _oss_provider);
        for (i = 0; i < MAX_OSS_MIDI; i++) {
                sprintf(sbuf, "/dev/midi%d", i);
                _tryopen(i, sbuf, _oss_provider);

                sprintf(sbuf, "/dev/midi%02d", i);
                _tryopen(i, sbuf, _oss_provider);
        }
}
int oss_midi_setup(void)
{
        static struct midi_driver driver;
        int i;

        driver.flags = 0;
        driver.poll = _oss_poll;
        driver.thread = _oss_thread;
        driver.enable = _oss_start;
        driver.disable = _oss_stop;
        driver.send = _oss_send;

        for (i = 0; i < MAX_MIDI_PORTS; i++) opened[i] = -1;
        if (!midi_provider_register("OSS", &driver)) return 0;
        return 1;
}
#endif
