Add support for fetching lyrics in background for selected songs

NEWS

@@ -10,6 +10,7 @@ ncmpcpp-0.8 (????-??-??)
 * Lyrics can now be fetched for songs with no tags.
 * libcurl dependency is no longer optional.
 * When an attempt to write tags fails, show detailed error message.
+* Support for fetching lyrics for selected items in background was added.
 
 ncmpcpp-0.7.7 (2016-10-31)
 * Fixed compilation on 32bit platforms.

doc/bindings

@@ -520,6 +520,9 @@
 #  toggle_lyrics_fetcher
 #
 #def_key "F"
+#  fetch_lyrics_in_background
+#
+#def_key "alt-l"
 #  toggle_fetching_lyrics_in_background
 #
 #def_key "ctrl-l"

src/actions.cpp

@@ -2273,6 +2273,20 @@ void ToggleMediaLibrarySortMode::run()
 	myLibrary->toggleSortMode();
 }
 
+bool FetchLyricsInBackground::canBeRun()
+{
+	m_hs = dynamic_cast<HasSongs *>(myScreen);
+	return m_hs != nullptr && m_hs->itemAvailable();
+}
+
+void FetchLyricsInBackground::run()
+{
+	auto songs = m_hs->getSelectedSongs();
+	for (const auto &s : songs)
+		myLyrics->fetchInBackground(s, true);
+	Statusbar::print("Selected songs queued for lyrics fetching");
+}
+
 bool RefetchLyrics::canBeRun()
 {
 	return myScreen == myLyrics;
@@ -2785,6 +2799,7 @@ void populateActions()
 	insert_action(new Actions::ToggleBrowserSortMode());
 	insert_action(new Actions::ToggleLibraryTagType());
 	insert_action(new Actions::ToggleMediaLibrarySortMode());
+	insert_action(new Actions::FetchLyricsInBackground());
 	insert_action(new Actions::RefetchLyrics());
 	insert_action(new Actions::SetSelectedItemsPriority());
 	insert_action(new Actions::ToggleOutput());

src/actions.h

@@ -137,6 +137,7 @@ enum class Type
 	ToggleBrowserSortMode,
 	ToggleLibraryTagType,
 	ToggleMediaLibrarySortMode,
+	FetchLyricsInBackground,
 	RefetchLyrics,
 	SetSelectedItemsPriority,
 	ToggleOutput,
@@ -1163,6 +1164,18 @@ private:
 	virtual void run() override;
 };
 
+struct FetchLyricsInBackground: BaseAction
+{
+	FetchLyricsInBackground()
+		: BaseAction(Type::FetchLyricsInBackground, "fetch_lyrics_in_background") { }
+
+private:
+	virtual bool canBeRun() override;
+	virtual void run() override;
+
+	HasSongs *m_hs;
+};
+
 struct RefetchLyrics: BaseAction
 {
 	RefetchLyrics(): BaseAction(Type::RefetchLyrics, "refetch_lyrics") { }

src/bindings.cpp

@@ -721,6 +721,8 @@ void BindingsConfiguration::generateDefaults()
 	if (notBound(k = stringToKey("L")))
 		bind(k, Actions::Type::ToggleLyricsFetcher);
 	if (notBound(k = stringToKey("F")))
+		bind(k, Actions::Type::FetchLyricsInBackground);
+	if (notBound(k = stringToKey("alt-l")))
 		bind(k, Actions::Type::ToggleFetchingLyricsInBackground);
 	if (notBound(k = stringToKey("ctrl-l")))
 		bind(k, Actions::Type::ToggleScreenLock);

src/help.cpp

@@ -230,6 +230,7 @@ void write_bindings(NC::Scrollpad &w)
 	key(w, Type::JumpToPositionInSong, "Jump to given position in playing song (formats: mm:ss, x%)");
 	key(w, Type::ShowSongInfo, "Show song info");
 	key(w, Type::ShowArtistInfo, "Show artist info");
+	key(w, Type::FetchLyricsInBackground, "Fetch lyrics for selected songs");
 	key(w, Type::ToggleLyricsFetcher, "Toggle lyrics fetcher");
 	key(w, Type::ToggleFetchingLyricsInBackground, "Toggle fetching lyrics for playing songs in background");
 	key(w, Type::ShowLyrics, "Show/hide song lyrics");