bindings: add support for defining and executing commands

doc/bindings

@@ -95,6 +95,24 @@
 ##      selected_items_adder, server_info, song_info,
 ##      sort_playlist_dialog, tiny_tag_editor.
 ##
+## 5) In addition to binding to a key, you can also bind actions
+##    or chains of actions to a command. If it comes to commands,
+##    syntax is very similar to defining keys. Here goes example
+##    definition of a command:
+##
+##      def_command "quit" [deferred]
+##        stop
+##        quit
+##
+##    If you execute the above command (which can be done by
+##    invoking action execute_command, typing 'quit' and pressing
+##    enter), ncmpcpp will stop the player and then quit. Note the
+##    presence of word 'deferred' enclosed in square brackets. It
+##    tells ncmpcpp to wait for confirmation (ie. pressing enter)
+##    after you typed quit. Instead of 'deferred', 'immediate'
+##    could be used. Then ncmpcpp will not wait for confirmation
+##    (enter) and will execute the command the moment it sees it.
+##
 ## Note: Both 'backspace' and 'backspace_2' are used because some
 ##       terminals interpret backspace using keycode of 'backspace'
 ##       and some the one of 'backspace_2'. You can get away with
@@ -191,6 +209,9 @@
 #def_key "-"
 #  volume_down
 #
+#def_key ":"
+#  execute_command
+#
 #def_key "tab"
 #  next_screen
 #

src/actions.cpp

@@ -972,6 +972,27 @@ void Stop::Run()
 	Mpd.Stop();
 }
 
+void ExecuteCommand::Run()
+{
+	using Global::wFooter;
+	Statusbar::lock();
+	Statusbar::put() << NC::fmtBold << ":" << NC::fmtBoldEnd;
+	wFooter->setGetStringHelper(Statusbar::Helpers::TryExecuteImmediateCommand());
+	std::string name = wFooter->getString();
+	wFooter->setGetStringHelper(Statusbar::Helpers::getString);
+	Statusbar::unlock();
+	if (name.empty())
+		return;
+	auto cmd = Bindings.findCommand(name);
+	if (cmd)
+	{
+		Statusbar::msg(1, "Executing %s...", name.c_str());
+		cmd->binding().execute();
+	}
+	else
+		Statusbar::msg("No command named \"%s\"", name.c_str());
+}
+
 bool MoveSortOrderUp::canBeRun() const
 {
 	return myScreen == mySortPlaylistDialog;
@@ -2576,6 +2597,7 @@ void populateActions()
 	insertAction(new NextSong());
 	insertAction(new Pause());
 	insertAction(new Stop());
+	insertAction(new ExecuteCommand());
 	insertAction(new SavePlaylist());
 	insertAction(new MoveSortOrderUp());
 	insertAction(new MoveSortOrderDown());

src/actions.h

@@ -31,7 +31,7 @@ enum ActionType
 	aDummy, aMouseEvent, aScrollUp, aScrollDown, aScrollUpArtist, aScrollUpAlbum, aScrollDownArtist,
 	aScrollDownAlbum, aPageUp, aPageDown, aMoveHome, aMoveEnd, aToggleInterface, aJumpToParentDirectory,
 	aPressEnter, aPressSpace, aPreviousColumn, aNextColumn, aMasterScreen, aSlaveScreen, aVolumeUp,
-	aVolumeDown, aDeletePlaylistItems, aDeleteStoredPlaylist, aDeleteBrowserItems, aReplaySong, aPrevious, aNext, aPause, aStop, aSavePlaylist,
+	aVolumeDown, aDeletePlaylistItems, aDeleteStoredPlaylist, aDeleteBrowserItems, aReplaySong, aPrevious, aNext, aPause, aStop, aExecuteCommand, aSavePlaylist,
 	aMoveSortOrderUp, aMoveSortOrderDown, aMoveSelectedItemsUp, aMoveSelectedItemsDown,
 	aMoveSelectedItemsTo, aAdd, aSeekForward, aSeekBackward, aToggleDisplayMode, aToggleSeparatorsBetweenAlbums,
 	aToggleLyricsFetcher, aToggleFetchingLyricsInBackground, aTogglePlayingSongCentering, aUpdateDatabase,
@@ -361,6 +361,14 @@ protected:
 	virtual void Run();
 };
 
+struct ExecuteCommand : public Action
+{
+	ExecuteCommand() : Action(aExecuteCommand, "execute_command") { }
+	
+protected:
+	virtual void Run();
+};
+
 struct SavePlaylist : public Action
 {
 	SavePlaylist() : Action(aSavePlaylist, "save_playlist") { }

src/bindings.cpp

@@ -189,53 +189,110 @@ Key Key::read(NC::Window &w)
 
 bool BindingsConfiguration::read(const std::string &file)
 {
+	enum class InProgress { None, Command, Key };
+	
 	bool result = true;
 	
 	std::ifstream f(file);
 	if (!f.is_open())
 		return result;
 	
+	// shared variables
+	InProgress in_progress = InProgress::None;
 	size_t line_no = 0;
-	bool key_def_in_progress = false;
+	std::string line;
-	Key key = Key::noOp;
 	Binding::ActionChain actions;
-	std::string line, strkey;
+	
+	// def_key specific variables
+	Key key = Key::noOp;
+	std::string strkey;
+	
+	// def_command specific variables
+	bool cmd_immediate = false;
+	std::string cmd_name;
 	
 	auto error = [&]() -> std::ostream & {
-		std::cerr << file << ":" << line_no << ": ";
+		std::cerr << file << ":" << line_no << ": error: ";
-		key_def_in_progress = false;
+		in_progress = InProgress::None;
 		result = false;
 		return std::cerr;
 	};
 	
-	auto bind_key_def = [&]() -> bool {
+	auto bind_in_progress = [&]() -> bool {
-		if (!actions.empty())
+		if (in_progress == InProgress::Command)
 		{
-			bind(key, actions);
+			if (!actions.empty())
-			actions.clear();
+			{
-			return true;
+				m_commands.insert(std::make_pair(cmd_name, Command(actions, cmd_immediate)));
+				actions.clear();
+				return true;
+			}
+			else
+			{
+				error() << "definition of command '" << cmd_name << "' cannot be empty\n";
+				return false;
+			}
 		}
-		else
+		else if (in_progress == InProgress::Key)
 		{
-			error() << "definition of key '" << strkey << "' cannot be empty.\n";
+			if (!actions.empty())
-			return false;
+			{
+				bind(key, actions);
+				actions.clear();
+				return true;
+			}
+			else
+			{
+				error() << "definition of key '" << strkey << "' cannot be empty\n";
+				return false;
+			}
 		}
+		return true;
 	};
 	
+	const char def_command[] = "def_command";
+	const char def_key[] = "def_key";
+	
 	while (!f.eof() && ++line_no)
 	{
 		getline(f, line);
 		if (line.empty() || line[0] == '#')
 			continue;
 		
-		if (!line.compare(0, 7, "def_key")) // beginning of key definition
+		// beginning of command definition
+		if (!line.compare(0, const_strlen(def_command), def_command))
 		{
-			if (key_def_in_progress)
+			if (!bind_in_progress())
+				break;
+			in_progress = InProgress::Command;
+			cmd_name = getEnclosedString(line, '"', '"', 0);
+			if (cmd_name.empty())
+			{
+				error() << "command must have non-empty name\n";
+				break;
+			}
+			if (m_commands.find(cmd_name) != m_commands.end())
+			{
+				error() << "redefinition of command '" << cmd_name << "'\n";
+				break;
+			}
+			std::string cmd_type = getEnclosedString(line, '[', ']', 0);
+			if (cmd_type == "immediate")
+				cmd_immediate = true;
+			else if (cmd_type == "deferred")
+				cmd_immediate = false;
+			else
 			{
-				if (!bind_key_def())
+				error() << "invalid type of command: '" << cmd_type << "'\n";
-					break;
+				break;
 			}
-			key_def_in_progress = true;
+		}
+		// beginning of key definition
+		else if (!line.compare(0, const_strlen(def_key), def_key))
+		{
+			if (!bind_in_progress())
+				break;
+			in_progress = InProgress::Key;
 			strkey = getEnclosedString(line, '"', '"', 0);
 			key = stringToKey(strkey);
 			if (key == Key::noOp)
@@ -262,8 +319,7 @@ bool BindingsConfiguration::read(const std::string &file)
 			break;
 		}
 	}
-	if (key_def_in_progress)
+	bind_in_progress();
-		bind_key_def();
 	f.close();
 	return result;
 }
@@ -318,6 +374,8 @@ void BindingsConfiguration::generateDefaults()
 	}
 	if (notBound(k = stringToKey("-")))
 		bind(k, aVolumeDown);
+	if (notBound(k = stringToKey(":")))
+		bind(k, aExecuteCommand);
 	if (notBound(k = stringToKey("tab")))
 		bind(k, aNextScreen);
 	if (notBound(k = stringToKey("shift_tab")))

src/bindings.h

@@ -22,6 +22,7 @@
 #define _BINDINGS_H
 
 #include <cassert>
+#include <unordered_map>
 #include "actions.h"
 #include "macro_utilities.h"
 
@@ -85,6 +86,20 @@ struct Binding
 		}
 	}
 	
+	bool execute() const {
+		bool result = false;
+		if (m_is_single) {
+			assert(m_action);
+			result = m_action->Execute();
+		} else {
+			for (auto it = m_chain->begin(); it != m_chain->end(); ++it)
+				if (!(*it)->Execute())
+					break;
+			result = true;
+		}
+		return result;
+	}
+	
 	bool isSingle() const {
 		return m_is_single;
 	}
@@ -105,16 +120,41 @@ private:
 	};
 };
 
+/// Represents executable command
+struct Command
+{
+	Command(const Binding &binding_, bool immediate_)
+	: m_binding(binding_), m_immediate(immediate_) { }
+	
+	const Binding &binding() const { return m_binding; }
+	bool immediate() const { return m_immediate; }
+	
+private:
+	Binding m_binding;
+	bool m_immediate;
+};
+
 /// Keybindings configuration
-struct BindingsConfiguration
+class BindingsConfiguration
 {
+	typedef std::unordered_map<std::string, Command> CommandsSet;
 	typedef std::multimap<Key, Binding> BindingsMap;
+	
+public:
 	typedef BindingsMap::iterator BindingIterator;
 	typedef BindingsMap::const_iterator ConstBindingIterator;
 	
 	bool read(const std::string &file);
 	void generateDefaults();
 	
+	const Command *findCommand(const std::string &name) {
+		const Command *ptr = 0;
+		auto it = m_commands.find(name);
+		if (it != m_commands.end())
+			ptr = &it->second;
+		return ptr;
+	}
+	
 	std::pair<BindingIterator, BindingIterator> get(const Key &k) {
 		return m_bindings.equal_range(k);
 	}
@@ -132,6 +172,7 @@ private:
 	}
 	
 	BindingsMap m_bindings;
+	CommandsSet m_commands;
 };
 
 extern BindingsConfiguration Bindings;

src/help.cpp

@@ -238,6 +238,7 @@ void Help::GetKeybindings()
 	KeyDesc(aSetCrossfade, "Set crossfade");
 	KeyDesc(aUpdateDatabase, "Start music database update");
 	w << '\n';
+	KeyDesc(aExecuteCommand, "Execute command");
 	KeyDesc(aApplyFilter, "Apply filter");
 	KeyDesc(aFindItemForward, "Find item forward");
 	KeyDesc(aFindItemBackward, "Find item backward");

src/ncmpcpp.cpp

@@ -237,7 +237,6 @@ int main(int argc, char **argv)
 			drawHeader();
 			past = Timer;
 		}
-		
 		// header stuff end
 		
 		if (input != Key::noOp)
@@ -249,22 +248,8 @@ int main(int argc, char **argv)
 		
 		auto k = Bindings.get(input);
 		for (; k.first != k.second; ++k.first)
-		{
+			if (k.first->second.execute())
-			Binding &b = k.first->second;
-			if (b.isSingle())
-			{
-				if (b.action()->Execute())
-					break;
-			}
-			else
-			{
-				auto chain = b.chain();
-				for (auto it = chain->begin(); it != chain->end(); ++it)
-					if (!(*it)->Execute())
-						break;
 				break;
-			}
-		}
 		
 		if (myScreen == myPlaylist)
 			myPlaylist->EnableHighlighting();

src/statusbar.cpp

@@ -22,6 +22,7 @@
 #include "settings.h"
 #include "status.h"
 #include "statusbar.h"
+#include "bindings.h"
 
 using Global::wFooter;
 
@@ -186,12 +187,13 @@ void Statusbar::Helpers::mpd()
 	Mpd.OrderDataFetching();
 }
 
-void Statusbar::Helpers::getString(const std::wstring &)
+bool Statusbar::Helpers::getString(const std::wstring &)
 {
 	Status::trace();
+	return true;
 }
 
-void Statusbar::Helpers::ApplyFilterImmediately::operator()(const std::wstring &ws)
+bool Statusbar::Helpers::ApplyFilterImmediately::operator()(const std::wstring &ws)
 {
 	using Global::myScreen;
 	// if input queue is not empty, we don't want to update filter since next
@@ -209,4 +211,19 @@ void Statusbar::Helpers::ApplyFilterImmediately::operator()(const std::wstring &
 		}
 		Status::trace();
 	}
+	return true;
+}
+
+bool Statusbar::Helpers::TryExecuteImmediateCommand::operator()(const std::wstring &ws)
+{
+	bool continue_ = true;
+	if (m_ws != ws)
+	{
+		m_ws = ws;
+		auto cmd = Bindings.findCommand(ToString(m_ws));
+		if (cmd && cmd->immediate())
+			continue_ = false;
+	}
+	Status::trace();
+	return continue_;
 }

src/statusbar.h

@@ -71,7 +71,7 @@ namespace Helpers {//
 void mpd();
 
 /// called each time user types another character while inside Window::getString
-void getString(const std::wstring &);
+bool getString(const std::wstring &);
 
 /// called each time user changes current filter (while being inside Window::getString)
 struct ApplyFilterImmediately
@@ -79,13 +79,21 @@ struct ApplyFilterImmediately
 	ApplyFilterImmediately(Filterable *f, const std::wstring &filter)
 	: m_f(f), m_ws(filter) { }
 	
-	void operator()(const std::wstring &ws);
+	bool operator()(const std::wstring &ws);
 	
 private:
 	Filterable *m_f;
 	std::wstring m_ws;
 };
 
+struct TryExecuteImmediateCommand
+{
+	bool operator()(const std::wstring &ws);
+	
+private:
+	std::wstring m_ws;
+};
+
 }
 
 }

src/window.cpp

@@ -552,7 +552,10 @@ std::string Window::getString(const std::string &base, size_t length_, size_t wi
 			mvwhline(m_window, y, minx, '*', maxx-minx);
 		
 		if (m_get_string_helper)
-			m_get_string_helper(*tmp);
+		{
+			if (!m_get_string_helper(*tmp))
+				break;
+		}
 		
 		wmove(m_window, y, x);
 		prefresh(m_window, 0, 0, m_start_y, m_start_x, m_start_y+m_height-1, m_start_x+m_width-1);

src/window.h

@@ -132,7 +132,7 @@ enum Where { wUp, wDown, wPageUp, wPageDown, wHome, wEnd };
 /// Helper function that is invoked each time one will want
 /// to obtain string from Window::getString() function
 /// @see Window::getString()
-typedef std::function<void(const std::wstring &)> GetStringHelper;
+typedef std::function<bool(const std::wstring &)> GetStringHelper;
 
 /// Initializes curses screen and sets some additional attributes
 /// @param window_title title of the window (has an effect only if pdcurses lib is used)