playlist: convert to C++

src/PlaylistControl.cxx

@@ -0,0 +1,293 @@
+/*
+ * Copyright (C) 2003-2013 The Music Player Daemon Project
+ * http://www.musicpd.org
+ *
+ * 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) any later version.
+ *
+ * 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, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+/*
+ * Functions for controlling playback on the playlist level.
+ *
+ */
+
+#include "config.h"
+#include "PlaylistInternal.hxx"
+#include "song.h"
+
+extern "C" {
+#include "player_control.h"
+}
+
+#include <glib.h>
+
+#undef G_LOG_DOMAIN
+#define G_LOG_DOMAIN "playlist"
+
+void
+playlist_stop(struct playlist *playlist, struct player_control *pc)
+{
+	if (!playlist->playing)
+		return;
+
+	assert(playlist->current >= 0);
+
+	g_debug("stop");
+	pc_stop(pc);
+	playlist->queued = -1;
+	playlist->playing = false;
+
+	if (playlist->queue.random) {
+		/* shuffle the playlist, so the next playback will
+		   result in a new random order */
+
+		unsigned current_position =
+			queue_order_to_position(&playlist->queue,
+						playlist->current);
+
+		queue_shuffle_order(&playlist->queue);
+
+		/* make sure that "current" stays valid, and the next
+		   "play" command plays the same song again */
+		playlist->current =
+			queue_position_to_order(&playlist->queue,
+						current_position);
+	}
+}
+
+enum playlist_result
+playlist_play(struct playlist *playlist, struct player_control *pc,
+	      int song)
+{
+	unsigned i = song;
+
+	pc_clear_error(pc);
+
+	if (song == -1) {
+		/* play any song ("current" song, or the first song */
+
+		if (queue_is_empty(&playlist->queue))
+			return PLAYLIST_RESULT_SUCCESS;
+
+		if (playlist->playing) {
+			/* already playing: unpause playback, just in
+			   case it was paused, and return */
+			pc_set_pause(pc, false);
+			return PLAYLIST_RESULT_SUCCESS;
+		}
+
+		/* select a song: "current" song, or the first one */
+		i = playlist->current >= 0
+			? playlist->current
+			: 0;
+	} else if (!queue_valid_position(&playlist->queue, song))
+		return PLAYLIST_RESULT_BAD_RANGE;
+
+	if (playlist->queue.random) {
+		if (song >= 0)
+			/* "i" is currently the song position (which
+			   would be equal to the order number in
+			   no-random mode); convert it to a order
+			   number, because random mode is enabled */
+			i = queue_position_to_order(&playlist->queue, song);
+
+		if (!playlist->playing)
+			playlist->current = 0;
+
+		/* swap the new song with the previous "current" one,
+		   so playback continues as planned */
+		queue_swap_order(&playlist->queue,
+				 i, playlist->current);
+		i = playlist->current;
+	}
+
+	playlist->stop_on_error = false;
+	playlist->error_count = 0;
+
+	playlist_play_order(playlist, pc, i);
+	return PLAYLIST_RESULT_SUCCESS;
+}
+
+enum playlist_result
+playlist_play_id(struct playlist *playlist, struct player_control *pc,
+		 int id)
+{
+	int song;
+
+	if (id == -1) {
+		return playlist_play(playlist, pc, id);
+	}
+
+	song = queue_id_to_position(&playlist->queue, id);
+	if (song < 0)
+		return PLAYLIST_RESULT_NO_SUCH_SONG;
+
+	return playlist_play(playlist, pc, song);
+}
+
+void
+playlist_next(struct playlist *playlist, struct player_control *pc)
+{
+	int next_order;
+	int current;
+
+	if (!playlist->playing)
+		return;
+
+	assert(!queue_is_empty(&playlist->queue));
+	assert(queue_valid_order(&playlist->queue, playlist->current));
+
+	current = playlist->current;
+	playlist->stop_on_error = false;
+
+	/* determine the next song from the queue's order list */
+
+	next_order = queue_next_order(&playlist->queue, playlist->current);
+	if (next_order < 0) {
+		/* no song after this one: stop playback */
+		playlist_stop(playlist, pc);
+
+		/* reset "current song" */
+		playlist->current = -1;
+	}
+	else
+	{
+		if (next_order == 0 && playlist->queue.random) {
+			/* The queue told us that the next song is the first
+			   song.  This means we are in repeat mode.  Shuffle
+			   the queue order, so this time, the user hears the
+			   songs in a different than before */
+			assert(playlist->queue.repeat);
+
+			queue_shuffle_order(&playlist->queue);
+
+			/* note that playlist->current and playlist->queued are
+			   now invalid, but playlist_play_order() will
+			   discard them anyway */
+		}
+
+		playlist_play_order(playlist, pc, next_order);
+	}
+
+	/* Consume mode removes each played songs. */
+	if(playlist->queue.consume)
+		playlist_delete(playlist, pc,
+				queue_order_to_position(&playlist->queue,
+							current));
+}
+
+void
+playlist_previous(struct playlist *playlist, struct player_control *pc)
+{
+	if (!playlist->playing)
+		return;
+
+	assert(queue_length(&playlist->queue) > 0);
+
+	if (playlist->current > 0) {
+		/* play the preceding song */
+		playlist_play_order(playlist, pc,
+				    playlist->current - 1);
+	} else if (playlist->queue.repeat) {
+		/* play the last song in "repeat" mode */
+		playlist_play_order(playlist, pc,
+				    queue_length(&playlist->queue) - 1);
+	} else {
+		/* re-start playing the current song if it's
+		   the first one */
+		playlist_play_order(playlist, pc, playlist->current);
+	}
+}
+
+enum playlist_result
+playlist_seek_song(struct playlist *playlist, struct player_control *pc,
+		   unsigned song, float seek_time)
+{
+	const struct song *queued;
+	unsigned i;
+	bool success;
+
+	if (!queue_valid_position(&playlist->queue, song))
+		return PLAYLIST_RESULT_BAD_RANGE;
+
+	queued = playlist_get_queued_song(playlist);
+
+	if (playlist->queue.random)
+		i = queue_position_to_order(&playlist->queue, song);
+	else
+		i = song;
+
+	pc_clear_error(pc);
+	playlist->stop_on_error = true;
+	playlist->error_count = 0;
+
+	if (!playlist->playing || (unsigned)playlist->current != i) {
+		/* seeking is not within the current song - prepare
+		   song change */
+
+		playlist->playing = true;
+		playlist->current = i;
+
+		queued = NULL;
+	}
+
+	struct song *the_song =
+		song_dup_detached(queue_get_order(&playlist->queue, i));
+	success = pc_seek(pc, the_song, seek_time);
+	if (!success) {
+		playlist_update_queued_song(playlist, pc, queued);
+
+		return PLAYLIST_RESULT_NOT_PLAYING;
+	}
+
+	playlist->queued = -1;
+	playlist_update_queued_song(playlist, pc, NULL);
+
+	return PLAYLIST_RESULT_SUCCESS;
+}
+
+enum playlist_result
+playlist_seek_song_id(struct playlist *playlist, struct player_control *pc,
+		      unsigned id, float seek_time)
+{
+	int song = queue_id_to_position(&playlist->queue, id);
+	if (song < 0)
+		return PLAYLIST_RESULT_NO_SUCH_SONG;
+
+	return playlist_seek_song(playlist, pc, song, seek_time);
+}
+
+enum playlist_result
+playlist_seek_current(struct playlist *playlist, struct player_control *pc,
+		      float seek_time, bool relative)
+{
+	if (!playlist->playing)
+		return PLAYLIST_RESULT_NOT_PLAYING;
+
+	if (relative) {
+		struct player_status status;
+		pc_get_status(pc, &status);
+
+		if (status.state != PLAYER_STATE_PLAY &&
+		    status.state != PLAYER_STATE_PAUSE)
+			return PLAYLIST_RESULT_NOT_PLAYING;
+
+		seek_time += (int)status.elapsed_time;
+	}
+
+	if (seek_time < 0)
+		seek_time = 0;
+
+	return playlist_seek_song(playlist, pc, playlist->current, seek_time);
+}