//
// C++ Implementation: SoundSystem
//
// Description:
//
//
// Author: Jally <jallyx@163.com>, (C) 2009
//
// Copyright: See COPYING file that comes with this distribution
//
//
#include "SoundSystem.h"

#ifdef HAVE_GST
#include "ProgramData.h"
#include "output.h"
#include "utils.h"
extern ProgramData progdt;

/**
 * 类构造函数.
 */
SoundSystem::SoundSystem():eltset(NULL), persist(false)
{
        g_datalist_init(&eltset);
        gettimeofday(&timestamp, NULL);
}

/**
 * 类析构函数.
 */
SoundSystem::~SoundSystem()
{
        GstElement *pipeline;

        if ( (pipeline = GST_ELEMENT(g_datalist_get_data(&eltset, "pipeline-element"))))
                gst_element_set_state(pipeline, GST_STATE_NULL);
        g_datalist_clear(&eltset);
}

/**
 * 初始化声音系统.
 */
void SoundSystem::InitSublayer()
{
        GstElement *pipeline;
        GstElement *filesrc, *decode, *volume, *convert, *sink;
        GstBus *bus;

        gst_init(NULL, NULL);
        pipeline = gst_pipeline_new("sound-system");
        g_datalist_set_data_full(&eltset, "pipeline-element", pipeline,
                                 GDestroyNotify(gst_object_unref));
        filesrc = gst_element_factory_make("filesrc", "source");
        g_datalist_set_data(&eltset, "filesrc-element", filesrc);
        decode = gst_element_factory_make("decodebin", "decode");
        g_datalist_set_data(&eltset, "decode-element", decode);
        volume = gst_element_factory_make("volume", "volume");
        g_datalist_set_data(&eltset, "volume-element", volume);
        convert = gst_element_factory_make("audioconvert", "convert");
        g_datalist_set_data(&eltset, "convert-element", convert);
        sink = gst_element_factory_make("autoaudiosink", "output");
        g_datalist_set_data(&eltset, "output-element", sink);

        gst_bin_add_many(GST_BIN(pipeline), filesrc, decode, volume, convert, sink, NULL);
        gst_element_link_many(filesrc, decode, NULL);
        gst_element_link_many(volume, convert, sink, NULL);
        g_signal_connect_swapped(decode, "pad-added", G_CALLBACK(LinkElement), &eltset);

        bus = gst_pipeline_get_bus(GST_PIPELINE(pipeline));
        gst_bus_add_signal_watch(GST_BUS(bus));
        g_signal_connect_swapped(bus, "message::error",
                         G_CALLBACK(ErrorMessageOccur), this);
        g_signal_connect_swapped(bus, "message::eos",
                         G_CALLBACK(EosMessageOccur), this);
        gst_object_unref(bus);

        g_object_set(volume, "volume", progdt.volume, NULL);
}

/**
 * 调整音量.
 * @param value 音量值
 */
void SoundSystem::AdjustVolume(double value)
{
        GstElement *volume;

        volume = GST_ELEMENT(g_datalist_get_data(&eltset, "volume-element"));
        g_object_set(volume, "volume", value, NULL);
}

/**
 * 播放音频文件.
 * @param file 音频文件
 * @note 如果时间间隔过短，系统将会忽略后一个请求.
 */
void SoundSystem::Playing(const char *file)
{
        GstElement *pipeline, *filesrc;
        struct timeval time;

        gettimeofday(&time, NULL);
        if (!FLAG_ISSET(progdt.sndfgs, 0) || (difftimeval(time, timestamp) < 0.1))
                return;

        if (persist)
                EosMessageOccur(this);
        persist = true;
        filesrc = GST_ELEMENT(g_datalist_get_data(&eltset, "filesrc-element"));
        g_object_set(filesrc, "location", file, NULL);
        pipeline = GST_ELEMENT(g_datalist_get_data(&eltset, "pipeline-element"));
        gst_element_set_state(pipeline, GST_STATE_PLAYING);
        timestamp = time;
}

/**
 * 停止播放.
 */
void SoundSystem::Stop()
{
        EosMessageOccur(this);
}

/**
 * 链接元素.
 */
void SoundSystem::LinkElement(GData **eltset, GstPad *pad)
{
        GstElement *volume;
        GstCaps *caps;
        GstStructure *str;
        GstPad *spad;

        caps = gst_pad_query_caps(pad, NULL);
        str = gst_caps_get_structure(caps, 0);
        volume = GST_ELEMENT(g_datalist_get_data(eltset, "volume-element"));
        if(strcasestr(gst_structure_get_name(str), "audio")
                 &&(spad = gst_element_get_compatible_pad(volume, pad, caps)))
                gst_pad_link(pad, spad);
        gst_caps_unref(caps);
}

/**
 * 错误响应处理函数.
 */
void SoundSystem::ErrorMessageOccur(SoundSystem *sndsys, GstMessage *message)
{
        GstElement *pipeline;
        GError *error;

        gst_message_parse_error(message, &error, NULL);
        pwarning(_("Failed to play the prompt tone, %s\n"), error->message);
        g_error_free(error);
        EosMessageOccur(sndsys);
        pipeline = GST_ELEMENT(g_datalist_get_data(&sndsys->eltset, "pipeline-element"));
        gst_element_set_state(pipeline, GST_STATE_NULL);
}

/**
 * 播放文件结束响应处理函数.
 */
void SoundSystem::EosMessageOccur(SoundSystem *sndsys)
{
        GstElement *pipeline, *decode, *volume;

        pipeline = GST_ELEMENT(g_datalist_get_data(&sndsys->eltset, "pipeline-element"));
        gst_element_set_state(pipeline, GST_STATE_READY);
        decode = GST_ELEMENT(g_datalist_get_data(&sndsys->eltset, "decode-element"));
        volume = GST_ELEMENT(g_datalist_get_data(&sndsys->eltset, "volume-element"));
        gst_element_unlink(decode, volume);
        sndsys->persist = false;
}
#else
SoundSystem::SoundSystem()
{}
SoundSystem::~SoundSystem()
{}
void SoundSystem::InitSublayer()
{}
void SoundSystem::AdjustVolume(double value)
{}
void SoundSystem::Playing(const char *file)
{}
void SoundSystem::Stop()
{}
#endif