/*      $NetBSD: bthset.c,v 1.9 2016/03/06 21:12:07 plunky Exp $        */

/*-
 * Copyright (c) 2006 Itronix Inc.
 * All rights reserved.
 *
 * Written by Iain Hibbert for Itronix Inc.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. The name of Itronix Inc. may not be used to endorse
 *    or promote products derived from this software without specific
 *    prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY ITRONIX INC. ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL ITRONIX INC. BE LIABLE FOR ANY
 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 */

#include <sys/cdefs.h>
__COPYRIGHT("@(#) Copyright (c) 2006 Itronix, Inc.  All rights reserved.");
__RCSID("$NetBSD: bthset.c,v 1.9 2016/03/06 21:12:07 plunky Exp $");

#include <sys/types.h>
#include <sys/audioio.h>
#include <sys/ioctl.h>
#include <sys/time.h>
#include <sys/uio.h>

#include <assert.h>
#include <bluetooth.h>
#include <err.h>
#include <event.h>
#include <fcntl.h>
#include <sdp.h>
#include <signal.h>
#include <stdarg.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <errno.h>

#include <dev/bluetooth/btdev.h>
#include <dev/bluetooth/btsco.h>

#include <netbt/rfcomm.h>

#define RING_INTERVAL   5       /* seconds */

__dead static void usage(void);

static void do_signal(int, short, void *);
static void do_ring(int, short, void *);
static void do_mixer(int, short, void *);
static void do_rfcomm(int, short, void *);
static void do_server(int, short, void *);
static int send_rfcomm(const char *, ...) __printflike(1, 2);

static int init_mixer(struct btsco_info *, const char *);
static int init_rfcomm(struct btsco_info *);
static int init_server(struct btsco_info *, int);

static void remove_pid(void);
static int write_pid(void);

static struct event sigint_ev;          /* bye bye */
static struct event sigusr1_ev; /* start ringing */
static struct event sigusr2_ev; /* stop ringing */
static struct event mixer_ev;           /* mixer changed */
static struct event rfcomm_ev;          /* headset speaks */
static struct event server_ev;          /* headset connecting */
static struct event ring_ev;            /* ring timer */

static mixer_ctrl_t vgs;        /* speaker control */
static mixer_ctrl_t vgm;        /* mic control */
static int ringing;             /* we are ringing */
static int verbose;             /* copy to stdout */
static int mx;                  /* mixer fd */
static int rf;                  /* rfcomm connection fd */
static int ag;                  /* rfcomm gateway fd */
static sdp_session_t ss;        /* SDP server session */

static char *command;           /* answer command */
static char *pidfile;           /* PID file name */

/* Headset Audio Gateway service record */
static uint8_t hset_data[] = {
        0x09, 0x00, 0x00,       //  uint16      ServiceRecordHandle
        0x0a, 0x00, 0x00, 0x00, //  uint32      0x00000000
        0x00,

        0x09, 0x00, 0x01,       //  uint16      ServiceClassIDList
        0x35, 0x06,             //  seq8(6)
        0x19, 0x11, 0x12,       //   uuid16     HeadsetAudioGateway
        0x19, 0x12, 0x03,       //   uuid16     GenericAudio

        0x09, 0x00, 0x04,       //  uint16      ProtocolDescriptorList
        0x35, 0x0c,             //  seq8(12)
        0x35, 0x03,             //   seq8(3)
        0x19, 0x01, 0x00,       //    uuid16    L2CAP
        0x35, 0x05,             //   seq8(5)
        0x19, 0x00, 0x03,       //    uuid16    RFCOMM
        0x08, 0x00,             //    uint8     %hset_channel%

        0x09, 0x00, 0x05,       //  uint16      BrowseGroupList
        0x35, 0x03,             //  seq8(3)
        0x19, 0x10, 0x02,       //   uuid16     PublicBrowseGroup

        0x09, 0x00, 0x06,       //  uint16      LanguageBaseAttributeIDList
        0x35, 0x09,             //  seq8(9)
        0x09, 0x65, 0x6e,       //   uint16     0x656e  ("en")
        0x09, 0x00, 0x6a,       //   uint16     106     (UTF-8)
        0x09, 0x01, 0x00,       //   uint16     PrimaryLanguageBaseID

        0x09, 0x00, 0x09,       //  uint16      BluetoothProfileDescriptorList
        0x35, 0x08,             //  seq8(8)
        0x35, 0x06,             //   seq8(6)
        0x19, 0x11, 0x08,       //    uuid16    Headset
        0x09, 0x01, 0x00,       //    uint16    v1.0

        0x09, 0x01, 0x00,       //  uint16      PrimaryLanguageBaseID + ServiceNameOffset
        0x25, 0x0d, 0x56, 0x6f, //  str8(13)    "Voice Gateway"
        0x69, 0x63, 0x65, 0x20,
        0x47, 0x61, 0x74, 0x65,
        0x77, 0x61, 0x79
};

static sdp_data_t hset_record = { hset_data + 0, hset_data + 89 };
static sdp_data_t hset_channel = { hset_data + 34, hset_data + 36 };

int
main(int ac, char *av[])
{
        struct btsco_info       info;
        const char              *mixer;
        int                     ch, channel;

        ag = rf = -1;
        verbose = 0;
        channel = 0;
        pidfile = getenv("BTHSET_PIDFILE");
        command = getenv("BTHSET_COMMAND");
        mixer = getenv("BTHSET_MIXER");
        if (mixer == NULL)
                mixer = "/dev/mixer";

        while ((ch = getopt(ac, av, "hc:m:p:s:v")) != EOF) {
                switch (ch) {
                case 'c':
                        command = optarg;
                        break;

                case 'm':
                        mixer = optarg;
                        break;

                case 'p':
                        pidfile = optarg;
                        break;

                case 's':
                        channel = atoi(optarg);
                        break;

                case 'v':
                        verbose = 1;
                        break;

                case 'h':
                default:
                        usage();
                }
        }

        if (mixer == NULL)
                usage();

        if ((channel < RFCOMM_CHANNEL_MIN || channel > RFCOMM_CHANNEL_MAX)
            && channel != 0)
                usage();

        if (write_pid() < 0)
                err(EXIT_FAILURE, "%s", pidfile);

        event_init();

        ringing = 0;
        evtimer_set(&ring_ev, do_ring, NULL);

        signal_set(&sigusr1_ev, SIGUSR1, do_signal, NULL);
        if (signal_add(&sigusr1_ev, NULL) < 0)
                err(EXIT_FAILURE, "SIGUSR1");

        signal_set(&sigusr2_ev, SIGUSR2, do_signal, NULL);
        if (signal_add(&sigusr2_ev, NULL) < 0)
                err(EXIT_FAILURE, "SIGUSR2");

        signal_set(&sigint_ev, SIGINT, do_signal, NULL);
        if (signal_add(&sigint_ev, NULL) < 0)
                err(EXIT_FAILURE, "SIGINT");

        if (init_mixer(&info, mixer) < 0)
                err(EXIT_FAILURE, "%s", mixer);

        if (channel == 0 && init_rfcomm(&info) < 0)
                err(EXIT_FAILURE, "%s", bt_ntoa(&info.raddr, NULL));

        if (channel && init_server(&info, channel) < 0)
                err(EXIT_FAILURE, "%d", channel);

        if (verbose) {
                printf("Headset Info:\n");
                printf("\tmixer: %s\n", mixer);
                printf("\tladdr: %s\n", bt_ntoa(&info.laddr, NULL));
                printf("\traddr: %s\n", bt_ntoa(&info.raddr, NULL));
                printf("\tchannel: %d\n", info.channel);
                printf("\tvgs.dev: %d, vgm.dev: %d\n", vgs.dev, vgm.dev);
                if (channel) printf("\tserver channel: %d\n", channel);
        }

        event_dispatch();

        err(EXIT_FAILURE, "event_dispatch");
}

static void
usage(void)
{

        fprintf(stderr,
                "usage: %s [-hv] [-c command] [-m mixer] [-p file] [-s channel]\n"
                "Where:\n"
                "\t-h           display this message\n"
                "\t-v           verbose output\n"
                "\t-c command   command to execute on answer\n"
                "\t-m mixer     mixer path\n"
                "\t-p file      write PID to file\n"
                "\t-s channel   register as audio gateway on channel\n"
                "", getprogname());

        exit(EXIT_FAILURE);
}

static void
do_signal(int s, short ev, void *arg)
{

        switch (s) {
        case SIGUSR1:
                ringing = 1;    /* start ringing */
                do_ring(0, 0, NULL);
                break;

        case SIGUSR2:
                ringing = 0;
                break;

        case SIGINT:
        default:
                exit(EXIT_SUCCESS);
        }
}

static void
do_ring(int s, short ev, void *arg)
{
        static struct timeval tv = { RING_INTERVAL, 0 };

        if (!ringing)
                return;

        send_rfcomm("RING");
        evtimer_add(&ring_ev, &tv);
}

/*
 * The mixer device has been twiddled. We check mic and speaker
 * settings and send the appropriate commands to the headset,
 */
static void
do_mixer(int s, short ev, void *arg)
{
        mixer_ctrl_t mc;
        int level;

        memcpy(&mc, &vgs, sizeof(mc));
        if (ioctl(mx, AUDIO_MIXER_READ, &mc) < 0)
                return;

        if (memcmp(&vgs, &mc, sizeof(mc))) {
                memcpy(&vgs, &mc, sizeof(mc));
                level = mc.un.value.level[AUDIO_MIXER_LEVEL_MONO] / BTSCO_DELTA;

                send_rfcomm("+VGS=%d", level);
        }

        memcpy(&mc, &vgm, sizeof(mc));
        if (ioctl(mx, AUDIO_MIXER_READ, &mc) < 0)
                return;

        if (memcmp(&vgm, &mc, sizeof(mc))) {
                memcpy(&vgm, &mc, sizeof(mc));
                level = mc.un.value.level[AUDIO_MIXER_LEVEL_MONO] / BTSCO_DELTA;

                send_rfcomm("+VGM=%d", level);
        }
}

/*
 * RFCOMM socket event.
 */
static void
do_rfcomm(int fd, short ev, void *arg)
{
        char buf[128];
        int len, level;

        memset(buf, 0, sizeof(buf));
        len = recv(rf, buf, sizeof(buf), 0);
        if (len <= 0) {
                if (ag < 0)
                        errx(EXIT_FAILURE, "Connection Lost");

                event_del(&rfcomm_ev);
                close(rf);
                rf = -1;
                ringing = 0;
                return;
        }

        if (verbose)
                printf("> %.*s\n", len, buf);

        if (len >= 7 && strncmp(buf, "AT+CKPD", 7) == 0) {
                if (ringing && command != NULL) {
                        if (verbose)
                                printf("%% %s\n", command);

                        system(command);
                }

                ringing = 0;
                send_rfcomm("OK");
                return;
        }

        if (len >= 7 && strncmp(buf, "AT+VGS=", 7) == 0) {
                level = atoi(buf + 7);
                if (level < 0 || level > 15)
                        return;

                vgs.un.value.level[AUDIO_MIXER_LEVEL_MONO] = level * BTSCO_DELTA;
                if (ioctl(mx, AUDIO_MIXER_WRITE, &vgs) < 0)
                        return;

                send_rfcomm("OK");
                return;
        }

        if (len >= 7 && strncmp(buf, "AT+VGM=", 7) == 0) {
                level = atoi(buf + 7);
                if (level < 0 || level > 15)
                        return;

                vgm.un.value.level[AUDIO_MIXER_LEVEL_MONO] = level * BTSCO_DELTA;
                if (ioctl(mx, AUDIO_MIXER_WRITE, &vgm) < 0)
                        return;

                send_rfcomm("OK");
                return;
        }

        send_rfcomm("ERROR");
}

/*
 * got an incoming connection on the AG socket.
 */
static void
do_server(int fd, short ev, void *arg)
{
        bdaddr_t *raddr = arg;
        struct sockaddr_bt addr;
        socklen_t len;
        int s;

        assert(raddr != NULL);

        len = sizeof(addr);
        s = accept(fd, (struct sockaddr *)&addr, &len);
        if (s < 0)
                return;

        if (rf >= 0
            || len != sizeof(addr)
            || addr.bt_len != sizeof(addr)
            || addr.bt_family != AF_BLUETOOTH
            || !bdaddr_same(raddr, &addr.bt_bdaddr)) {
                close(s);
                return;
        }

        rf = s;
        event_set(&rfcomm_ev, rf, EV_READ | EV_PERSIST, do_rfcomm, NULL);
        if (event_add(&rfcomm_ev, NULL) < 0)
                err(EXIT_FAILURE, "rfcomm_ev");
}

/*
 * send a message to the RFCOMM socket
 */
static int
send_rfcomm(const char *msg, ...)
{
        struct iovec iov[3];
        char buf[128];
        va_list ap;

        if (verbose) {
                fputs("< ", stdout);
                va_start(ap, msg);
                vprintf(msg, ap);
                va_end(ap);
                putchar('\n');
        }

        iov[0].iov_base = iov[2].iov_base = __UNCONST("\r\n");
        iov[0].iov_len = iov[2].iov_len = 2;
        va_start(ap, msg);
        iov[1].iov_base = buf;
        iov[1].iov_len = vsnprintf(buf, sizeof(buf), msg, ap);
        va_end(ap);

        return writev(rf, iov, __arraycount(iov));
}

/*
 * Initialise mixer event
 */
static int
init_mixer(struct btsco_info *info, const char *mixer)
{

        mx = open(mixer, O_WRONLY, 0);
        if (mx < 0)
                return -1;

        if (ioctl(mx, BTSCO_GETINFO, info) < 0)
                return -1;

        /* get initial vol settings */
        memset(&vgs, 0, sizeof(vgs));
        vgs.dev = info->vgs;
        if (ioctl(mx, AUDIO_MIXER_READ, &vgs) < 0)
                return -1;

        memset(&vgm, 0, sizeof(vgm));
        vgm.dev = info->vgm;
        if (ioctl(mx, AUDIO_MIXER_READ, &vgm) < 0)
                return -1;

        /* set up mixer changed event */
        if (fcntl(mx, F_SETFL, O_ASYNC) < 0)
                return -1;

        signal_set(&mixer_ev, SIGIO, do_mixer, NULL);
        if (signal_add(&mixer_ev, NULL) < 0)
                return -1;

        return 0;
}

/*
 * Initialise RFCOMM socket
 */
static int
init_rfcomm(struct btsco_info *info)
{
        struct sockaddr_bt addr;

        rf = socket(PF_BLUETOOTH, SOCK_STREAM, BTPROTO_RFCOMM);
        if (rf < 0)
                return -1;

        memset(&addr, 0, sizeof(addr));
        addr.bt_len = sizeof(addr);
        addr.bt_family = AF_BLUETOOTH;
        bdaddr_copy(&addr.bt_bdaddr, &info->laddr);

        if (bind(rf, (struct sockaddr *)&addr, sizeof(addr)) < 0)
                return -1;

        bdaddr_copy(&addr.bt_bdaddr, &info->raddr);
        addr.bt_channel = info->channel;

        if (connect(rf, (struct sockaddr *)&addr, sizeof(addr)) < 0)
                return -1;

        event_set(&rfcomm_ev, rf, EV_READ | EV_PERSIST, do_rfcomm, NULL);
        if (event_add(&rfcomm_ev, NULL) < 0)
                return -1;

        return 0;
}

/*
 * Initialise server socket
 */
static int
init_server(struct btsco_info *info, int channel)
{
        struct sockaddr_bt addr;

        ag = socket(PF_BLUETOOTH, SOCK_STREAM, BTPROTO_RFCOMM);
        if (ag < 0)
                return -1;

        memset(&addr, 0, sizeof(addr));
        addr.bt_len = sizeof(addr);
        addr.bt_family = AF_BLUETOOTH;
        addr.bt_channel = channel;
        bdaddr_copy(&addr.bt_bdaddr, &info->laddr);

        if (bind(ag, (struct sockaddr *)&addr, sizeof(addr)) < 0)
                return -1;

        if (listen(ag, 1) < 0)
                return -1;

        event_set(&server_ev, ag, EV_READ | EV_PERSIST, do_server, &info->raddr);
        if (event_add(&server_ev, NULL) < 0)
                return -1;

        sdp_set_uint(&hset_channel, channel);

        ss = sdp_open_local(NULL);
        if (ss == NULL)
                return -1;

        if (!sdp_record_insert(ss, &info->laddr, NULL, &hset_record)) {
                sdp_close(ss);
                return -1;
        }

        return 0;
}

static void
remove_pid(void)
{

        if (pidfile == NULL)
                return;

        unlink(pidfile);
}

static int
write_pid(void)
{
        char *buf;
        int fd, len;

        if (pidfile == NULL)
                return 0;

        fd = open(pidfile, O_WRONLY | O_CREAT | O_TRUNC, 0644);
        if (fd < 0)
                return -1;

        len = asprintf(&buf, "%d\n", getpid());
        if (len > 0)
                write(fd, buf, len);

        if (len >= 0 && buf != NULL)
                free(buf);

        close (fd);

        return atexit(remove_pid);
}