1 files changed, 465 insertions, 0 deletions
diff --git a/src/db/ProxyDatabasePlugin.cxx b/src/db/ProxyDatabasePlugin.cxx
new file mode 100644
index 000000000..2b8850f26
--- /dev/null
+++ b/src/db/ProxyDatabasePlugin.cxx
@@ -0,0 +1,465 @@
+/*
+ * Copyright (C) 2003-2012 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.
+ */
+
+#include "config.h"
+#include "ProxyDatabasePlugin.hxx"
+#include "DatabasePlugin.hxx"
+#include "DatabaseSelection.hxx"
+#include "DatabaseError.hxx"
+#include "PlaylistVector.hxx"
+#include "Directory.hxx"
+#include "Song.hxx"
+#include "gcc.h"
+#include "ConfigData.hxx"
+#include "tag/TagBuilder.hxx"
+#include "util/Error.hxx"
+#include "util/Domain.hxx"
+
+#undef MPD_DIRECTORY_H
+#undef MPD_SONG_H
+#include <mpd/client.h>
+
+#include <cassert>
+#include <string>
+#include <list>
+
+class ProxyDatabase : public Database {
+	std::string host;
+	unsigned port;
+
+	struct mpd_connection *connection;
+	Directory *root;
+
+public:
+	static Database *Create(const config_param &param,
+				Error &error);
+
+	virtual bool Open(Error &error) override;
+	virtual void Close() override;
+	virtual Song *GetSong(const char *uri_utf8,
+				     Error &error) const override;
+	virtual void ReturnSong(Song *song) const;
+
+	virtual bool Visit(const DatabaseSelection &selection,
+			   VisitDirectory visit_directory,
+			   VisitSong visit_song,
+			   VisitPlaylist visit_playlist,
+			   Error &error) const override;
+
+	virtual bool VisitUniqueTags(const DatabaseSelection &selection,
+				     enum tag_type tag_type,
+				     VisitString visit_string,
+				     Error &error) const override;
+
+	virtual bool GetStats(const DatabaseSelection &selection,
+			      DatabaseStats &stats,
+			      Error &error) const override;
+
+protected:
+	bool Configure(const config_param &param, Error &error);
+};
+
+static constexpr Domain libmpdclient_domain("libmpdclient");
+
+static constexpr struct {
+	enum tag_type d;
+	enum mpd_tag_type s;
+} tag_table[] = {
+	{ TAG_ARTIST, MPD_TAG_ARTIST },
+	{ TAG_ALBUM, MPD_TAG_ALBUM },
+	{ TAG_ALBUM_ARTIST, MPD_TAG_ALBUM_ARTIST },
+	{ TAG_TITLE, MPD_TAG_TITLE },
+	{ TAG_TRACK, MPD_TAG_TRACK },
+	{ TAG_NAME, MPD_TAG_NAME },
+	{ TAG_GENRE, MPD_TAG_GENRE },
+	{ TAG_DATE, MPD_TAG_DATE },
+	{ TAG_COMPOSER, MPD_TAG_COMPOSER },
+	{ TAG_PERFORMER, MPD_TAG_PERFORMER },
+	{ TAG_COMMENT, MPD_TAG_COMMENT },
+	{ TAG_DISC, MPD_TAG_DISC },
+	{ TAG_MUSICBRAINZ_ARTISTID, MPD_TAG_MUSICBRAINZ_ARTISTID },
+	{ TAG_MUSICBRAINZ_ALBUMID, MPD_TAG_MUSICBRAINZ_ALBUMID },
+	{ TAG_MUSICBRAINZ_ALBUMARTISTID,
+	  MPD_TAG_MUSICBRAINZ_ALBUMARTISTID },
+	{ TAG_MUSICBRAINZ_TRACKID, MPD_TAG_MUSICBRAINZ_TRACKID },
+	{ TAG_NUM_OF_ITEM_TYPES, MPD_TAG_COUNT }
+};
+
+gcc_const
+static enum mpd_tag_type
+Convert(enum tag_type tag_type)
+{
+	for (auto i = &tag_table[0]; i->d != TAG_NUM_OF_ITEM_TYPES; ++i)
+		if (i->d == tag_type)
+			return i->s;
+
+	return MPD_TAG_COUNT;
+}
+
+static bool
+CheckError(struct mpd_connection *connection, Error &error)
+{
+	const auto code = mpd_connection_get_error(connection);
+	if (code == MPD_ERROR_SUCCESS)
+		return true;
+
+	error.Set(libmpdclient_domain, (int)code,
+		  mpd_connection_get_error_message(connection));
+	mpd_connection_clear_error(connection);
+	return false;
+}
+
+Database *
+ProxyDatabase::Create(const config_param &param, Error &error)
+{
+	ProxyDatabase *db = new ProxyDatabase();
+	if (!db->Configure(param, error)) {
+		delete db;
+		db = NULL;
+	}
+
+	return db;
+}
+
+bool
+ProxyDatabase::Configure(const config_param &param, gcc_unused Error &error)
+{
+	host = param.GetBlockValue("host", "");
+	port = param.GetBlockValue("port", 0u);
+
+	return true;
+}
+
+bool
+ProxyDatabase::Open(Error &error)
+{
+	connection = mpd_connection_new(host.empty() ? NULL : host.c_str(),
+					port, 0);
+	if (connection == NULL) {
+		error.Set(libmpdclient_domain, (int)MPD_ERROR_OOM, "Out of memory");
+		return false;
+	}
+
+	if (!CheckError(connection, error)) {
+		mpd_connection_free(connection);
+		return false;
+	}
+
+	root = Directory::NewRoot();
+
+	return true;
+}
+
+void
+ProxyDatabase::Close()
+{
+	assert(connection != nullptr);
+
+	root->Free();
+	mpd_connection_free(connection);
+}
+
+static Song *
+Convert(const struct mpd_song *song);
+
+Song *
+ProxyDatabase::GetSong(const char *uri, Error &error) const
+{
+	// TODO: implement
+	// TODO: auto-reconnect
+
+	if (!mpd_send_list_meta(connection, uri)) {
+		CheckError(connection, error);
+		return nullptr;
+	}
+
+	struct mpd_song *song = mpd_recv_song(connection);
+	Song *song2 = song != nullptr
+		? Convert(song)
+		: nullptr;
+	mpd_song_free(song);
+	if (!mpd_response_finish(connection)) {
+		if (song2 != nullptr)
+			song2->Free();
+
+		CheckError(connection, error);
+		return nullptr;
+	}
+
+	if (song2 == nullptr)
+		error.Format(db_domain, DB_NOT_FOUND, "No such song: %s", uri);
+
+	return song2;
+}
+
+void
+ProxyDatabase::ReturnSong(Song *song) const
+{
+	assert(song != nullptr);
+	assert(song->IsInDatabase());
+	assert(song->IsDetached());
+
+	song->Free();
+}
+
+static bool
+Visit(struct mpd_connection *connection, const char *uri,
+      bool recursive, VisitDirectory visit_directory, VisitSong visit_song,
+      VisitPlaylist visit_playlist, Error &error);
+
+static bool
+Visit(struct mpd_connection *connection,
+      bool recursive, const struct mpd_directory *directory,
+      VisitDirectory visit_directory, VisitSong visit_song,
+      VisitPlaylist visit_playlist, Error &error)
+{
+	const char *path = mpd_directory_get_path(directory);
+
+	if (visit_directory) {
+		Directory *d = Directory::NewGeneric(path, &detached_root);
+		bool success = visit_directory(*d, error);
+		d->Free();
+		if (!success)
+			return false;
+	}
+
+	if (recursive &&
+	    !Visit(connection, path, recursive,
+		   visit_directory, visit_song, visit_playlist, error))
+		return false;
+
+	return true;
+}
+
+static void
+Copy(TagBuilder &tag, enum tag_type d_tag,
+     const struct mpd_song *song, enum mpd_tag_type s_tag)
+{
+
+	for (unsigned i = 0;; ++i) {
+		const char *value = mpd_song_get_tag(song, s_tag, i);
+		if (value == NULL)
+			break;
+
+		tag.AddItem(d_tag, value);
+	}
+}
+
+static Song *
+Convert(const struct mpd_song *song)
+{
+	Song *s = Song::NewDetached(mpd_song_get_uri(song));
+
+	s->mtime = mpd_song_get_last_modified(song);
+	s->start_ms = mpd_song_get_start(song) * 1000;
+	s->end_ms = mpd_song_get_end(song) * 1000;
+
+	TagBuilder tag;
+	tag.SetTime(mpd_song_get_duration(song));
+
+	for (const auto *i = &tag_table[0]; i->d != TAG_NUM_OF_ITEM_TYPES; ++i)
+		Copy(tag, i->d, song, i->s);
+
+	s->tag = tag.Commit();
+
+	return s;
+}
+
+static bool
+Visit(const struct mpd_song *song,
+      VisitSong visit_song, Error &error)
+{
+	if (!visit_song)
+		return true;
+
+	Song *s = Convert(song);
+	bool success = visit_song(*s, error);
+	s->Free();
+
+	return success;
+}
+
+static bool
+Visit(const struct mpd_playlist *playlist,
+      VisitPlaylist visit_playlist, Error &error)
+{
+	if (!visit_playlist)
+		return true;
+
+	PlaylistInfo p(mpd_playlist_get_path(playlist),
+		       mpd_playlist_get_last_modified(playlist));
+
+	return visit_playlist(p, detached_root, error);
+}
+
+class ProxyEntity {
+	struct mpd_entity *entity;
+
+public:
+	explicit ProxyEntity(struct mpd_entity *_entity)
+		:entity(_entity) {}
+
+	ProxyEntity(const ProxyEntity &other) = delete;
+
+	ProxyEntity(ProxyEntity &&other)
+		:entity(other.entity) {
+		other.entity = nullptr;
+	}
+
+	~ProxyEntity() {
+		if (entity != nullptr)
+			mpd_entity_free(entity);
+	}
+
+	ProxyEntity &operator=(const ProxyEntity &other) = delete;
+
+	operator const struct mpd_entity *() const {
+		return entity;
+	}
+};
+
+static std::list<ProxyEntity>
+ReceiveEntities(struct mpd_connection *connection)
+{
+	std::list<ProxyEntity> entities;
+	struct mpd_entity *entity;
+	while ((entity = mpd_recv_entity(connection)) != NULL)
+		entities.push_back(ProxyEntity(entity));
+
+	mpd_response_finish(connection);
+	return entities;
+}
+
+static bool
+Visit(struct mpd_connection *connection, const char *uri,
+      bool recursive, VisitDirectory visit_directory, VisitSong visit_song,
+      VisitPlaylist visit_playlist, Error &error)
+{
+	if (!mpd_send_list_meta(connection, uri))
+		return CheckError(connection, error);
+
+	std::list<ProxyEntity> entities(ReceiveEntities(connection));
+	if (!CheckError(connection, error))
+		return false;
+
+	for (const auto &entity : entities) {
+		switch (mpd_entity_get_type(entity)) {
+		case MPD_ENTITY_TYPE_UNKNOWN:
+			break;
+
+		case MPD_ENTITY_TYPE_DIRECTORY:
+			if (!Visit(connection, recursive,
+				   mpd_entity_get_directory(entity),
+				   visit_directory, visit_song, visit_playlist,
+				   error))
+				return false;
+			break;
+
+		case MPD_ENTITY_TYPE_SONG:
+			if (!Visit(mpd_entity_get_song(entity), visit_song,
+				   error))
+				return false;
+			break;
+
+		case MPD_ENTITY_TYPE_PLAYLIST:
+			if (!Visit(mpd_entity_get_playlist(entity),
+				   visit_playlist, error))
+				return false;
+			break;
+		}
+	}
+
+	return CheckError(connection, error);
+}
+
+bool
+ProxyDatabase::Visit(const DatabaseSelection &selection,
+		     VisitDirectory visit_directory,
+		     VisitSong visit_song,
+		     VisitPlaylist visit_playlist,
+		     Error &error) const
+{
+	// TODO: match
+	// TODO: auto-reconnect
+
+	return ::Visit(connection, selection.uri, selection.recursive,
+		       visit_directory, visit_song, visit_playlist,
+		       error);
+}
+
+bool
+ProxyDatabase::VisitUniqueTags(const DatabaseSelection &selection,
+			       enum tag_type tag_type,
+			       VisitString visit_string,
+			       Error &error) const
+{
+	enum mpd_tag_type tag_type2 = Convert(tag_type);
+	if (tag_type2 == MPD_TAG_COUNT) {
+		error.Set(libmpdclient_domain, "Unsupported tag");
+		return false;
+	}
+
+	if (!mpd_search_db_tags(connection, tag_type2))
+		return CheckError(connection, error);
+
+	// TODO: match
+	(void)selection;
+
+	if (!mpd_search_commit(connection))
+		return CheckError(connection, error);
+
+	bool result = true;
+
+	struct mpd_pair *pair;
+	while (result &&
+	       (pair = mpd_recv_pair_tag(connection, tag_type2)) != nullptr) {
+		result = visit_string(pair->value, error);
+		mpd_return_pair(connection, pair);
+	}
+
+	return mpd_response_finish(connection) &&
+		CheckError(connection, error) &&
+		result;
+}
+
+bool
+ProxyDatabase::GetStats(const DatabaseSelection &selection,
+			DatabaseStats &stats, Error &error) const
+{
+	// TODO: match
+	(void)selection;
+
+	struct mpd_stats *stats2 =
+		mpd_run_stats(connection);
+	if (stats2 == nullptr)
+		return CheckError(connection, error);
+
+	stats.song_count = mpd_stats_get_number_of_songs(stats2);
+	stats.total_duration = mpd_stats_get_db_play_time(stats2);
+	stats.artist_count = mpd_stats_get_number_of_artists(stats2);
+	stats.album_count = mpd_stats_get_number_of_albums(stats2);
+	mpd_stats_free(stats2);
+
+	return true;
+}
+
+const DatabasePlugin proxy_db_plugin = {
+	"proxy",
+	ProxyDatabase::Create,
+};