/*
 * Copyright 2011 Free Software Foundation, Inc.
 *
 * This file is part of GNU Radio
 *
 * GNU Radio 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 3, or (at your option)
 * any later version.
 *
 * GNU Radio 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 GNU Radio; see the file COPYING.  If not, write to
 * the Free Software Foundation, Inc., 51 Franklin Street,
 * Boston, MA 02110-1301, USA.
 */

#include "gr_audio_registry.h"
#include <boost/foreach.hpp>
#include <gr_prefs.h>
#include <stdexcept>
#include <vector>
#include <iostream>

/***********************************************************************
 * Create registries
 **********************************************************************/

struct source_entry_t{
    reg_prio_type prio;
    std::string arch;
    source_factory_t source;
};

static std::vector<source_entry_t> &get_source_registry(void){
    static std::vector<source_entry_t> _registry;
    return _registry;
}

struct sink_entry_t{
    reg_prio_type prio;
    std::string arch;
    sink_factory_t sink;
};

static std::vector<sink_entry_t> &get_sink_registry(void){
    static std::vector<sink_entry_t> _registry;
    return _registry;
}

/***********************************************************************
 * Register functions
 **********************************************************************/
void audio_register_source(
    reg_prio_type prio, const std::string &arch, source_factory_t source
){
    source_entry_t entry;
    entry.prio = prio;
    entry.arch = arch;
    entry.source = source;
    get_source_registry().push_back(entry);
}

void audio_register_sink(
    reg_prio_type prio, const std::string &arch, sink_factory_t sink
){
    sink_entry_t entry;
    entry.prio = prio;
    entry.arch = arch;
    entry.sink = sink;
    get_sink_registry().push_back(entry);
}

/***********************************************************************
 * Factory functions
 **********************************************************************/
static std::string default_arch_name(void){
    return gr_prefs::singleton()->get_string("audio", "audio_module", "auto");
}

static void do_arch_warning(const std::string &arch){
    if (arch == "auto") return; //no warning when arch not specified
    std::cerr << "Could not find audio architecture \"" << arch << "\" in registry." << std::endl;
    std::cerr << "    Defaulting to the first available architecture..." << std::endl;
}

audio_source::sptr audio_make_source(
    int sampling_rate,
    const std::string device_name,
    bool ok_to_block
){
    if (get_source_registry().empty()){
        throw std::runtime_error("no available audio source factories");
    }

    std::string arch = default_arch_name();
    source_entry_t entry = get_source_registry().front();

    BOOST_FOREACH(const source_entry_t &e, get_source_registry()){
        if (e.prio > entry.prio) entry = e; //entry is highest prio
        if (arch != e.arch) continue; //continue when no match
        return e.source(sampling_rate, device_name, ok_to_block);
    }
    //std::cout << "Audio source arch: " << entry.name << std::endl;
    return entry.source(sampling_rate, device_name, ok_to_block);
}

audio_sink::sptr audio_make_sink(
    int sampling_rate,
    const std::string device_name,
    bool ok_to_block
){
    if (get_sink_registry().empty()){
        throw std::runtime_error("no available audio sink factories");
    }

    std::string arch = default_arch_name();
    sink_entry_t entry = get_sink_registry().front();

    BOOST_FOREACH(const sink_entry_t &e, get_sink_registry()){
        if (e.prio > entry.prio) entry = e; //entry is highest prio
        if (arch != e.arch) continue; //continue when no match
        return e.sink(sampling_rate, device_name, ok_to_block);
    }
    do_arch_warning(arch);
    //std::cout << "Audio sink arch: " << entry.name << std::endl;
    return entry.sink(sampling_rate, device_name, ok_to_block);
}