Create wesnoth.music_list.previous, along with the __cfg field for tracks (#1728)

src/scripting/lua_audio.cpp

@@ -13,6 +13,7 @@ See the COPYING file for more details.
 
 #include "lua_audio.hpp"
 
+#include "log.hpp"
 #include "lua/lua.h"
 #include "lua/lauxlib.h"
 #include "scripting/lua_common.hpp"
@@ -22,12 +23,18 @@ See the COPYING file for more details.
 #include "preferences/general.hpp"
 #include <set>
 
+static lg::log_domain log_audio("audio");
+#define DBG_AUDIO LOG_STREAM(debug, log_audio)
+#define LOG_AUDIO LOG_STREAM(info, log_audio)
+#define ERR_AUDIO LOG_STREAM(err, log_audio)
+
 static const char* Track = "music track";
 
 class lua_music_track {
 	std::shared_ptr<sound::music_track> track;
 public:
 	explicit lua_music_track(int i) : track(sound::get_track(i)) {}
+	explicit lua_music_track(std::shared_ptr<sound::music_track> new_track) : track(new_track) {}
 	bool valid() const {
 		return track && track->valid();
 	}
@@ -51,6 +58,12 @@ static lua_music_track* push_track(lua_State* L, int i) {
 	return trk;
 }
 
+static lua_music_track* push_track(lua_State* L, std::shared_ptr<sound::music_track> new_track) {
+	lua_music_track* trk = new(L) lua_music_track(new_track);
+	luaL_setmetatable(L, Track);
+	return trk;
+}
+
 static lua_music_track* get_track(lua_State* L, int i) {
 	return static_cast<lua_music_track*>(luaL_checkudata(L, i, Track));
 }
@@ -71,10 +84,17 @@ static int impl_music_get(lua_State* L) {
 		return 1;
 	}
 	const char* m = luaL_checkstring(L, 2);
+
 	if(strcmp(m, "current") == 0) {
 		push_track(L, sound::get_current_track());
 		return 1;
 	}
+
+	if(strcmp(m, "previous") == 0) {
+		push_track(L, sound::get_previous_music_track());
+		return 1;
+	}
+
 	if(strcmp(m, "current_i") == 0) {
 		size_t i = sound::get_current_track();
 		if(i == sound::get_num_tracks()) {
@@ -227,6 +247,17 @@ static int impl_track_get(lua_State* L) {
 	return_int_attrib("ms_after", track->ms_after());
 	return_string_attrib("name", track->id());
 	return_string_attrib("title", track->title());
+
+	return_cfg_attrib("__cfg",
+						cfg["append"]=track->append();
+						cfg["shuffle"]=track->shuffle();
+						cfg["immediate"]=track->immediate();
+						cfg["once"]=track->play_once();
+						cfg["ms_before"]=track->ms_before();
+						cfg["ms_after"]=track->ms_after();
+						cfg["name"]=track->id();
+						cfg["title"]=track->title());
+
 	return luaW_getmetafield(L, 1, m);
 }
 

src/sound.cpp

@@ -177,6 +177,7 @@ std::vector<std::string> played_before;
 std::vector<std::shared_ptr<sound::music_track>> current_track_list;
 std::shared_ptr<sound::music_track> current_track;
 unsigned int current_track_index = 0;
+std::shared_ptr<sound::music_track> previous_track;
 
 std::vector<std::shared_ptr<sound::music_track>>::const_iterator find_track(const sound::music_track& track)
 {
@@ -193,6 +194,14 @@ unsigned int get_current_track()
 {
 	return current_track_index;
 }
+std::shared_ptr<music_track> get_previous_music_track()
+{
+	return previous_track;
+}
+void set_previous_track(std::shared_ptr<music_track> track)
+{
+	previous_track = track;
+}
 
 unsigned int get_num_tracks()
 {
@@ -541,6 +550,7 @@ void stop_UI_sound()
 
 void play_music_once(const std::string& file)
 {
+	set_previous_track(current_track);
 	current_track = std::make_shared<music_track>(file);
 	current_track->set_play_once(true);
 	current_track_index = current_track_list.size();
@@ -566,6 +576,7 @@ void play_music()
 
 void play_track(unsigned int i)
 {
+	set_previous_track(current_track);
 	if(i >= current_track_list.size()) {
 		current_track = choose_track();
 	} else {
@@ -655,6 +666,7 @@ void play_music_config(const config& music_node, int i)
 
 	// If they say play once, we don't alter playlist.
 	if(track.play_once()) {
+		set_previous_track(current_track);
 		current_track = std::make_shared<music_track>(track);
 		current_track_index = current_track_list.size();
 		play_music();
@@ -690,6 +702,7 @@ void play_music_config(const config& music_node, int i)
 
 	// They can tell us to start playing this list immediately.
 	if(track.immediate()) {
+		set_previous_track(current_track);
 		current_track = *iter;
 		current_track_index = iter - current_track_list.begin();
 		play_music();
@@ -703,6 +716,7 @@ void music_thinker::process(events::pump_info& info)
 	if(preferences::music_on()) {
 		if(!music_start_time && !current_track_list.empty() && !Mix_PlayingMusic()) {
 			// Pick next track, add ending time to its start time.
+			set_previous_track(current_track);
 			current_track = choose_track();
 			music_start_time = info.ticks();
 			no_fading = true;
@@ -774,6 +788,7 @@ void commit_music_changes()
 	}
 
 	// FIXME: we don't pause ms_before on this first track.  Should we?
+	set_previous_track(current_track);
 	current_track = choose_track();
 	play_music();
 }

src/sound.hpp

@@ -15,6 +15,7 @@
 #pragma once
 
 #include "events.hpp"
+#include "sound_music_track.hpp"
 
 #include <string>
 
@@ -104,6 +105,7 @@ void set_bell_volume(int vol);
 void set_UI_volume(int vol);
 
 unsigned int get_current_track();
+std::shared_ptr<sound::music_track> get_previous_music_track();
 unsigned int get_num_tracks();
 void remove_track(unsigned int i);
 void play_track(unsigned int i);