#include <string> /*sorry, I feel comfortable using std::strings.*/
#include <gst/gst.h>
#include <glib.h>

/*Global vars*/
GstElement *pipeline=NULL, *textoverlay=NULL;
GMainLoop *loop=NULL;
bool sub_loaded=false;

const char *avipath = "hardcoded-path-to-avi-file";
const char *srtpath = "hardcoded-path-to-srt-file";

/*Various functions*/

static void no_more_pads(GstElement *element, gpointer data);

static gboolean bus_call (GstBus *bus, GstMessage *msg, gpointer data)
{

  switch (GST_MESSAGE_TYPE (msg)) {

    case GST_MESSAGE_EOS:
      g_print ("End of stream\n");
      g_main_loop_quit (loop);
      break;

    case GST_MESSAGE_ERROR: {
      gchar  *debug;
      GError *error;

      gst_message_parse_error (msg, &error, &debug);
      g_free (debug);

      g_printerr ("Error: %s\n", error->message);
      g_error_free (error);

      g_main_loop_quit (loop);
      break;
    }
    default:
      break;
  }

  return TRUE;
}

static void on_pad_added (GstElement *element, GstPad *pad, gpointer data)
{
    std::string mime_type;
    GstElement *queue, *decoder, *converter, *sink, *parser;
    GstPad *sinkpad;

    /*get mime-type*/
    GstCaps* caps = gst_pad_get_caps (pad);
    GstStructure* structure = gst_caps_get_structure(caps, 0);
    mime_type = gst_structure_get_name(structure);
    gst_caps_unref(caps);

    /*plug a queue in the pad and decide what to do according to the mimetype*/
    queue = gst_element_factory_make("queue", NULL);
    sinkpad = gst_element_get_static_pad(queue, "sink");
    gst_bin_add(GST_BIN(pipeline), queue);
    gst_pad_link(pad, sinkpad);
    gst_object_unref(sinkpad);

    /*now check the mimetype and decide what to do*/
    if (mime_type.find("video") != mime_type.npos)
    {/*the video stream. I assume an XVID/DIVX stream*/

        decoder = gst_element_factory_make("ffdec_mpeg4", NULL);
        converter = gst_element_factory_make("ffmpegcolorspace", NULL);
        textoverlay = gst_element_factory_make("textoverlay", NULL);
        sink = gst_element_factory_make("xvimagesink", NULL);

        gst_bin_add_many(GST_BIN(pipeline), decoder, converter, textoverlay, sink, NULL);
        gst_element_link_many(queue, decoder, converter, textoverlay, sink, NULL);

        gst_element_set_state(queue, GST_STATE_PAUSED);
        gst_element_set_state(decoder, GST_STATE_PAUSED);
        gst_element_set_state(converter, GST_STATE_PAUSED);
        gst_element_set_state(textoverlay, GST_STATE_PAUSED);
        gst_element_set_state(sink, GST_STATE_PAUSED);
    }
    else
    {/*the audio stream. I assume an mp3 stream.*/

        parser = gst_element_factory_make("mp3parse", NULL);
        decoder = gst_element_factory_make("mad", NULL);
        converter = gst_element_factory_make("audioconvert", NULL);
        sink = gst_element_factory_make("alsasink", NULL);

        gst_bin_add_many(GST_BIN(pipeline), parser, decoder, converter, sink, NULL);
        gst_element_link_many(queue, parser, decoder, converter, sink, NULL);

        gst_element_set_state(queue, GST_STATE_PAUSED);
        gst_element_set_state(parser, GST_STATE_PAUSED);
        gst_element_set_state(decoder, GST_STATE_PAUSED);
        gst_element_set_state(converter, GST_STATE_PAUSED);
        gst_element_set_state(sink, GST_STATE_PAUSED);
    }

}

void load_sub()
{
    GstElement *source, *parser, *queue;

    source = gst_element_factory_make("filesrc", NULL);
    parser = gst_element_factory_make("subparse", NULL);
    queue = gst_element_factory_make("queue", NULL);

    gst_bin_add_many(GST_BIN(pipeline), source, parser, queue, NULL);

    g_object_set(G_OBJECT(source), "location", srtpath, NULL);
    gst_element_set_state(source, GST_STATE_PAUSED);

    gst_element_link_many(source, parser, queue, textoverlay, NULL);

    gst_element_set_state(parser, GST_STATE_PAUSED);
    gst_element_set_state(queue, GST_STATE_PAUSED);


    no_more_pads(NULL, NULL);
}

static void no_more_pads(GstElement *element, gpointer data)
{
    if (!sub_loaded)
    {
        sub_loaded = true;
        load_sub();
    }
    else
    {
        gst_element_set_state(pipeline, GST_STATE_PLAYING);
    }
}


int main(int argc, char *argv[])
{
    GstElement *source=NULL, *demuxer=NULL;
    GstBus *bus;
    gst_init(&argc, &argv);

    loop = g_main_loop_new(NULL, FALSE);

    pipeline = gst_pipeline_new("pipeline");

    source = gst_element_factory_make("filesrc", NULL);
    demuxer = gst_element_factory_make("avidemux", NULL);

    g_object_set(G_OBJECT(source), "location", avipath, NULL);

    bus = gst_pipeline_get_bus(GST_PIPELINE(pipeline));
    gst_bus_add_watch(bus, bus_call, NULL);
    gst_object_unref(bus);

    gst_bin_add_many(GST_BIN(pipeline), source, demuxer, NULL);
    gst_element_link(source, demuxer);

    g_signal_connect (demuxer, "pad-added", G_CALLBACK(on_pad_added), NULL);
    g_signal_connect (demuxer, "no-more-pads", G_CALLBACK(no_more_pads), NULL);

    gst_element_set_state(pipeline, GST_STATE_PAUSED);
    g_main_loop_run(loop);

    gst_element_set_state(pipeline, GST_STATE_NULL);
    gst_object_unref(GST_OBJECT(pipeline));

    return 0;
}