refactor: move the Job implementation

The jobset has been moved into the Lua::Manager class and can generically
run any job on the "Lua" job queue.

The job has been moved into the SaveGameManager class so that any code
can load game data as Json in a job.

src/SaveGameManager.cpp

@@ -17,6 +17,29 @@ static const char s_saveDirName[] = "savefiles";
 
 static const int s_saveVersion = 90;
 
+// A simple job to load a savegame into a Json object
+class LoadGameToJsonJob : public Job
+{
+public:
+ LoadGameToJsonJob(std::string_view filename, void(*callback)(std::string_view, const Json &)) :
+ m_filename(filename), m_callback(callback)
+ {
+ }
+
+ virtual void OnRun() {
+ m_rootNode = SaveGameManager::LoadGameToJson(m_filename);
+ };
+ virtual void OnFinish() {
+ m_callback(m_filename, m_rootNode);
+ };
+ virtual void OnCancel() {};
+private:
+ std::string m_filename;
+ Json m_rootNode;
+ void(*m_callback)(std::string_view, const Json &);
+};
+
+
 void SaveGameManager::Init()
 {
  if (!FileSystem::userFiles.MakeDirectory(s_saveDirName)) {
@@ -59,6 +82,11 @@ Json SaveGameManager::LoadGameToJson(const std::string &filename)
  return JsonUtils::LoadJsonSaveFile(FileSystem::JoinPathBelow(s_saveDirName, filename), FileSystem::userFiles);
 }
 
+Job *SaveGameManager::LoadGameToJsonJob(std::string_view filename, void(*callback)(std::string_view, const Json &))
+{
+ return new class LoadGameToJsonJob(filename, callback);
+}
+
 Game *SaveGameManager::LoadGame(const std::string &name)
 {
  Output("SaveGameManager::LoadGame('%s')\n", name.c_str());

src/SaveGameManager.h

@@ -11,6 +11,7 @@
 #include <vector>
 
 class Game;
+class Job;
 
 class SaveGameManager {
 public:
@@ -48,6 +49,19 @@ class SaveGameManager {
  */
  static Json LoadGameToJson(const std::string &name);
 
+ /** Create a job which can be scheduled on a job queue to load the game as
+ * a Json object.
+ * This is provided as LoadGameToJson can be expensive.
+ *
+ * The \p callback is called in the main thread with the Json data once the
+ * job has completed.
+ *
+ * \param[in] name The name of the savegame to load.
+ * \param[in] callback A callback to be called once the data has been loaded.
+ * \return On success, a newly-created Job which can be passed to a job queue.
+ */
+ static Job *LoadGameToJsonJob(std::string_view name, void(*callback)(std::string_view, const Json &));
+
  /** Save the game.
  * NOTE: This function will throw an exception if an error occurs while
  * saving the game.

src/lua/LuaGame.cpp

@@ -25,49 +25,6 @@
 #include "galaxy/Galaxy.h"
 #include "pigui/LuaPiGui.h"
 
-/* A class to provide Jobs for various game tasks.
- * The initial driver was to handle loading of savegame statistics in the
- * background, but it was made generic enough to allow adding other jobs. */
-class LuaGameJobs
-{
-private:
- class SaveGameJob : public Job
- {
- public:
- SaveGameJob(std::string_view filename, void(*callback)(std::string_view, const Json &)) :
- m_filename(filename), m_callback(callback)
- {
- }
-
- virtual void OnRun() {
- m_rootNode = SaveGameManager::LoadGameToJson(m_filename);
- };
- virtual void OnFinish() {
- m_callback(m_filename, m_rootNode);
- };
- virtual void OnCancel() {};
- private:
- std::string m_filename;
- Json m_rootNode;
- void(*m_callback)(std::string_view, const Json &);
- };
-
- JobSet m_jobs;
-
-public:
- LuaGameJobs() :
- m_jobs(Pi::GetAsyncJobQueue())
- {
- }
-
- void jobLoadGameToJson(std::string_view filename, void(*callback)(std::string_view, const Json &))
- {
- m_jobs.Order(new SaveGameJob(filename, callback));
- }
-};
-
-static LuaGameJobs *gameJobs = nullptr;
-
 /*
  * Interface: Game
  *
@@ -198,7 +155,7 @@ static void onSaveGameStatsJobFinished(std::string_view filename, const Json &ro
 static int l_game_savegame_stats(lua_State *l)
 {
  const std::string filename = LuaPull<std::string>(l, 1);
- gameJobs->jobLoadGameToJson(filename, onSaveGameStatsJobFinished);
+ Lua::manager->ScheduleJob(SaveGameManager::LoadGameToJsonJob(filename, onSaveGameStatsJobFinished));
  return 0;
 }
 
@@ -847,7 +804,5 @@ void LuaGame::Register()
  lua_setfield(l, -2, "Game");
  lua_pop(l, 1);
 
- gameJobs = new LuaGameJobs();
-
  LUA_DEBUG_END(l, 0);
 }

src/lua/LuaManager.cpp

@@ -3,14 +3,15 @@
 
 #include "LuaManager.h"
 #include "FileSystem.h"
+#include "Pi.h"
 #include "utils.h"
 
 #include <cstdlib>
 
 bool instantiated = false;
 
 LuaManager::LuaManager() :
- m_lua(0)
+ m_lua(0), m_jobs(Pi::GetAsyncJobQueue())
 {
  if (instantiated) {
  Output("Can't instantiate more than one LuaManager");
@@ -51,3 +52,10 @@ void LuaManager::CollectGarbage()
 {
  lua_gc(m_lua, LUA_GCCOLLECT, 0);
 }
+
+void LuaManager::ScheduleJob(Job *job)
+{
+ if (job) {
+ m_jobs.Order(job);
+ }
+}

src/lua/LuaManager.h

@@ -4,6 +4,7 @@
 #ifndef _LUAMANAGER_H
 #define _LUAMANAGER_H
 
+#include "JobQueue.h"
 #include "LuaUtils.h"
 
 class LuaManager {
@@ -15,11 +16,15 @@ class LuaManager {
  size_t GetMemoryUsage() const;
  void CollectGarbage();
 
+ // Schedule a job to be run on the LuaManager job queue
+ void ScheduleJob(Job *job);
+
 private:
  LuaManager(const LuaManager &);
  LuaManager &operator=(const LuaManager &) = delete;
 
  lua_State *m_lua;
+ JobSet m_jobs;
 };
 
 #endif