/*
 * Copyright (C) 2005-2008 by Daniel Wagner
 * Copyright (C) 2005-2008 by Pieter Palmers
 *
 * This file is part of FFADO
 * FFADO = Free FireWire (pro-)audio drivers for Linux
 *
 * FFADO is based upon FreeBoB.
 *
 * 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) version 3 of the License.
 *
 * 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, see <http://www.gnu.org/licenses/>.
 *
 */

/*
 * This version uses the CPP API
 */

#include "config.h"
#include "version.h"

#include <semaphore.h>

#include "libffado/ffado.h"

#include "debugmodule/debugmodule.h"
#include "fbtypes.h"
#include "devicemanager.h"
#include "ffadodevice.h"

/* Work around a bug in dbus-c++ 0.9.0 which prevents compilation under gcc7 */
#ifndef DBUS_HAS_RECURSIVE_MUTEX
#define DBUS_HAS_RECURSIVE_MUTEX
#endif

#include <dbus-c++/dbus.h>
#include "controlserver.h"
#include "libcontrol/BasicElements.h"

#include "libutil/Functors.h"

#include <signal.h>

#include <argp.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>

#include <vector>
#include <string>
#include <iostream>
#include <sstream>

using namespace std;

DECLARE_GLOBAL_DEBUG_MODULE;

// DBUS stuff
DBus::BusDispatcher dispatcher;
DBusControl::Container *container = NULL;
DBus::Connection * global_conn;
DeviceManager *m_deviceManager = NULL;

// signal handler
int run=1;
sem_t run_sem;

static void sighandler (int sig)
{
    run = 0;
    dispatcher.leave();
    sem_post(&run_sem);
}

// global's
const char *argp_program_version = PACKAGE_STRING;
const char *argp_program_bug_address = PACKAGE_BUGREPORT;

// Program documentation.
static char doc[] = "ffado-dbus-server -- expose the mixer features of connected FFADO devices through DBus\n\n"
                    ;

// A description of the arguments we accept.
static char args_doc[] = "";

struct arguments
{
    short silent;
    short verbose;
    int   use_cache;
    int   port;
    int   node_id;
    int   node_id_set;
    const char* args[2];
};

// The options we understand.
static struct argp_option options[] = {
    {"quiet",    'q',       0,    0,  "Don't produce any output" },
    {"silent",   's',       0,    OPTION_ALIAS },

    {"verbose",  'v', "level",    0,  "Produce verbose output" },
#if ENABLE_DISCOVERY_CACHE
    {"cache",    'c', "enable",   0,  "Use AVC model cache" },
#endif

    {"node",     'n',    "id",    0,  "Only expose mixer of a device on a specific node" },
    {"port",     'p',    "nr",    0,  "IEEE1394 Port to use" },
    { 0 }
};

//-------------------------------------------------------------

// Parse a single option.
static error_t
parse_opt( int key, char* arg, struct argp_state* state )
{
    // Get the input argument from `argp_parse', which we
    // know is a pointer to our arguments structure.
    struct arguments* arguments = ( struct arguments* ) state->input;
    char* tail;

    errno = 0;
    switch (key) {
    case 'q': case 's':
        arguments->silent = 1;
        break;
    case 'v':
        if (arg) {
            arguments->verbose = strtol( arg, &tail, 0 );
            if ( errno ) {
                debugError( "Could not parse 'verbose' argument\n" );
                return ARGP_ERR_UNKNOWN;
            }
        }
        break;
    case 'c':
        if (arg) {
            arguments->use_cache = strtol( arg, &tail, 0 );
            if ( errno ) {
                fprintf( stderr,  "Could not parse 'cache' argument\n" );
                return ARGP_ERR_UNKNOWN;
            }
        }
        break;
    case 'p':
        if (arg) {
            arguments->port = strtol( arg, &tail, 0 );
            if ( errno ) {
                debugError( "Could not parse 'port' argument\n" );
                return ARGP_ERR_UNKNOWN;
            }
        } else {
            if ( errno ) {
                debugError("Could not parse 'port' argumen\n" );
                return ARGP_ERR_UNKNOWN;
            }
        }
        break;
    case 'n':
        if (arg) {
            arguments->node_id = strtol( arg, &tail, 0 );
            if ( errno ) {
                debugError( "Could not parse 'node' argument\n" );
                return ARGP_ERR_UNKNOWN;
            }
            arguments->node_id_set=1;
        } else {
            if ( errno ) {
                debugError("Could not parse 'node' argumen\n" );
                return ARGP_ERR_UNKNOWN;
            }
        }
        break;
    case ARGP_KEY_ARG:
        if (state->arg_num >= 1) {
            // Too many arguments.
            argp_usage( state );
        }
        arguments->args[state->arg_num] = arg;
        break;
    case ARGP_KEY_END:
        if (state->arg_num < 0) {
        // Not enough arguments.
        argp_usage( state );
        }
        break;
    default:
        return ARGP_ERR_UNKNOWN;
    }
    return 0;
}

// Our argp parser.
static struct argp argp = { options, parse_opt, args_doc, doc };

int exitfunction( int retval ) {
    debugOutput( DEBUG_LEVEL_NORMAL, "Debug output flushed...\n" );
    flushDebugOutput();
    return retval;
}

void
preUpdateHandler()
{
    debugOutput( DEBUG_LEVEL_NORMAL, "got pre-update notification...\n" );
    // stop receiving dbus events since the control structure is going to
    // be changed
    dispatcher.leave();
}

void
postUpdateHandler()
{
    debugOutput( DEBUG_LEVEL_NORMAL, "got post-update notification...\n" );
    // the signal handlers registered by the elements should have taken
    // care of updating the control tree

    // signal that we can start receiving dbus events again
    sem_post(&run_sem);
}

int
main( int argc, char **argv )
{
    struct arguments arguments;

    printf("-----------------------------------------------\n");
    printf("FFADO Control DBUS service\n");
    printf("Part of the FFADO project -- www.ffado.org\n");
    printf("Version: %s\n", PACKAGE_VERSION);
    printf("(C) 2008-2021, Pieter Palmers and others\n");
    printf("This program comes with ABSOLUTELY NO WARRANTY.\n");
    printf("-----------------------------------------------\n\n");

    // check the library version
    const char *libversion = ffado_get_version();
    const char *progversion = PACKAGE_STRING;
    if(strcmp(libversion, progversion) != 0) {
        printf("Library version mismatch. (required: %s, present: %s)\n", progversion, libversion);
        printf("Please run this application against the exact corresponding library\n");
        printf("it was compiled for. The most common cause for this is having more\n");
        printf("than one version of libffado installed.\n\n");
        return exitfunction(-1);
    }

    // Default values.
    arguments.silent      = 0;
    arguments.verbose     = DEBUG_LEVEL_NORMAL;
    arguments.use_cache   = 1;
    arguments.port        = 0;
    arguments.node_id     = 0;
    arguments.node_id_set = 0; // if we don't specify a node, discover all
    arguments.args[0]     = "";
    arguments.args[1]     = "";

    setDebugLevel(arguments.verbose);

    // Parse our arguments; every option seen by `parse_opt' will
    // be reflected in `arguments'.
    if ( argp_parse ( &argp, argc, argv, 0, 0, &arguments ) ) {
        debugError("Could not parse command line\n" );
        return exitfunction(-1);
    }

    printMessage(" Discovering devices...\n");
    m_deviceManager = new DeviceManager();
    if ( !m_deviceManager ) {
        debugError("Could not allocate device manager\n" );
        return exitfunction(-1);
    }
    if ( !m_deviceManager->initialize() ) {
        debugError("Could not initialize device manager\n" );
        delete m_deviceManager;
        return exitfunction(-1);
    }
    if ( arguments.verbose ) {
        m_deviceManager->setVerboseLevel(arguments.verbose);
    }
    if ( !m_deviceManager->discover(arguments.use_cache) ) {
        debugError("Could not discover devices\n" );
        delete m_deviceManager;
        return exitfunction(-1);
    }

    // add pre-update handler
    Util::Functor* preupdate_functor = new Util::CallbackFunctor0< void (*)() >
                ( &preUpdateHandler, false );
    if ( !preupdate_functor ) {
        debugFatal( "Could not create pre-update handler\n" );
        return false;
    }
    if(!m_deviceManager->registerPreUpdateNotification(preupdate_functor)) {
        debugError("could not register pre-update notifier");
    }
    // add post-update handler
    Util::Functor* postupdate_functor = new Util::CallbackFunctor0< void (*)() >
                ( &postUpdateHandler, false );
    if ( !postupdate_functor ) {
        debugFatal( "Could not create post-update handler\n" );
        return false;
    }
    if(!m_deviceManager->registerPostUpdateNotification(postupdate_functor)) {
        debugError("could not register post-update notifier");
    }

    signal (SIGINT, sighandler);
    signal (SIGTERM, sighandler);

    DBus::_init_threading();

    // set up DBUS stuff
    DBus::default_dispatcher = &dispatcher;
    DBus::Connection conn = DBus::Connection::SessionBus();
    global_conn = &conn;
    conn.request_name("org.ffado.Control");

    // lock the control tree such that it does not get modified while we build our view
    m_deviceManager->lockControl();
    container = new DBusControl::Container(conn, "/org/ffado/Control/DeviceManager", 
                                            NULL, *m_deviceManager);
    // unlock the control tree since the tree is built
    m_deviceManager->unlockControl();

    printMessage("DBUS service running\n");
    printMessage("press ctrl-c to stop it & exit\n");
    
    while(run) {
        debugOutput( DEBUG_LEVEL_NORMAL, "dispatching...\n");
        dispatcher.enter();
        debugOutput( DEBUG_LEVEL_NORMAL, " dispatcher exited...\n");
        sem_wait(&run_sem);
        debugOutput( DEBUG_LEVEL_NORMAL, " activity handled...\n");
    }
    
    if(!m_deviceManager->unregisterPreUpdateNotification(preupdate_functor)) {
        debugError("could not unregister pre update notifier");
    }
    delete preupdate_functor;
    if(!m_deviceManager->unregisterPostUpdateNotification(postupdate_functor)) {
        debugError("could not unregister post update notifier");
    }
    delete postupdate_functor;
    delete container;

    signal (SIGINT, SIG_DFL);
    signal (SIGTERM, SIG_DFL);

    printMessage("server stopped\n");
    delete m_deviceManager;
    return exitfunction(0);
}