/**
 * Copyright 2013 (c) Anna Schumaker.
 */
#include <core/audio.h>
extern "C" {
#include <core/collection.h>
#include <core/history.h>
#include <core/tempq.h>
#include <core/string.h>
}


static struct file audio_file;
static GstElement *audio_player = NULL;

static bool _pause_enabled = false;
static unsigned int _pause_count =  0;

static struct track *cur_track = NULL;
static AudioDriver *cur_driver = NULL;


static void save_state()
{
	file_open(&audio_file, OPEN_WRITE);
	file_writef(&audio_file, "%u\n", cur_track->tr_dbe.dbe_index);
	file_close(&audio_file);
}

static void _load_track(struct track *track, bool start_playback)
{
	cur_track = track;
	if (!track)
		return;

	cur_driver->load(track);
	if (start_playback)
		audio :: play();
	else
		audio :: pause();
	save_state();
}

static bool continue_playback()
{
	bool ret = true;

	if (_pause_enabled) {
		if (_pause_count == 0) {
			ret = false;
			_pause_enabled = false;
		} else
			_pause_count--;
	}

	return ret;
}



AudioDriver :: AudioDriver()
{
	cur_driver = this;
}

AudioDriver :: ~AudioDriver()
{
	cur_driver = NULL;
}

void AudioDriver :: eos()
{
	struct track *track;

	if (cur_track) {
		track_played(cur_track);
		queue_updated(collection_get_queue(), cur_track);
	}

	track = tempq_next();
	if (!track)
		track = queue_next(collection_get_queue());
	_load_track(track, continue_playback());
}



void audio_init(int *argc, char ***argv)
{
	unsigned int track;

	gst_init(argc, argv);
	audio_player = gst_element_factory_make("playbin", "ocarina_player");

	file_init(&audio_file, "cur_track", 0);
	if (file_open(&audio_file, OPEN_READ)) {
		file_readf(&audio_file, "%u", &track);
		file_close(&audio_file);
		audio :: load_track(track_get(track));
	}
}

void audio_deinit()
{
	gst_element_set_state(audio_player, GST_STATE_NULL);
	gst_object_unref(audio_player);
	audio_player = NULL;

	gst_deinit();
}

void audio :: play()
{
	if (cur_track)
		cur_driver->play();
}

void audio :: pause()
{
	if (cur_track)
		cur_driver->pause();
}

void audio :: seek_to(int64_t pos)
{
	if (cur_track)
		cur_driver->seek_to(pos);
}

void audio :: stop()
{
	pause();
	seek_to(0);
}

int64_t audio :: position()
{
	if (cur_track)
		return cur_driver->position();
	return 0;
}

int64_t audio :: duration()
{
	if (cur_track)
		return cur_driver->duration();
	return 0;
}

void audio :: next()
{
	struct track *track = tempq_next();
	if (!track)
		track = queue_next(collection_get_queue());
	_load_track(track, cur_driver->is_playing());
	if (cur_track)
		history_add(cur_track);
}

void audio :: prev()
{
	_load_track(history_prev(), cur_driver->is_playing());
}

void audio :: load_track(struct track *track)
{
	if (!track || track == cur_track)
		return;

	_load_track(track, cur_driver->is_playing());
	history_add(cur_track);
}

struct track *audio :: current_track()
{
	return cur_track;
}

void audio :: pause_after(bool enabled, unsigned int n)
{
	if (n > _pause_count)
		enabled = true;

	_pause_enabled = enabled;
	_pause_count = n;
}

bool audio :: pause_enabled()
{
	return _pause_enabled;
}

unsigned int audio :: pause_count()
{
	return _pause_count;
}

AudioDriver *audio :: get_driver()
{
	return cur_driver;
}

GstElement *audio_get_player()
{
	return audio_player;
}