chore: remove Singleton & replace getIApp with getApp (#5514)

src/controllers/plugins/LuaAPI.cpp

@@ -65,7 +65,7 @@ namespace chatterino::lua::api {
 
 int c2_register_command(lua_State *L)
 {
-    auto *pl = getIApp()->getPlugins()->getPluginByStatePtr(L);
+    auto *pl = getApp()->getPlugins()->getPluginByStatePtr(L);
     if (pl == nullptr)
     {
         luaL_error(L, "internal error: no plugin");
@@ -99,7 +99,7 @@ int c2_register_command(lua_State *L)
 
 int c2_register_callback(lua_State *L)
 {
-    auto *pl = getIApp()->getPlugins()->getPluginByStatePtr(L);
+    auto *pl = getApp()->getPlugins()->getPluginByStatePtr(L);
     if (pl == nullptr)
     {
         luaL_error(L, "internal error: no plugin");
@@ -133,7 +133,7 @@ int c2_register_callback(lua_State *L)
 
 int c2_log(lua_State *L)
 {
-    auto *pl = getIApp()->getPlugins()->getPluginByStatePtr(L);
+    auto *pl = getApp()->getPlugins()->getPluginByStatePtr(L);
     if (pl == nullptr)
     {
         luaL_error(L, "c2_log: internal error: no plugin?");
@@ -154,7 +154,7 @@ int c2_log(lua_State *L)
 
 int c2_later(lua_State *L)
 {
-    auto *pl = getIApp()->getPlugins()->getPluginByStatePtr(L);
+    auto *pl = getApp()->getPlugins()->getPluginByStatePtr(L);
     if (pl == nullptr)
     {
         return luaL_error(L, "c2.later: internal error: no plugin?");
@@ -257,7 +257,7 @@ int g_load(lua_State *L)
 
 int loadfile(lua_State *L, const QString &str)
 {
-    auto *pl = getIApp()->getPlugins()->getPluginByStatePtr(L);
+    auto *pl = getApp()->getPlugins()->getPluginByStatePtr(L);
     if (pl == nullptr)
     {
         return luaL_error(L, "loadfile: internal error: no plugin?");
@@ -307,7 +307,7 @@ int searcherAbsolute(lua_State *L)
     name = name.replace('.', QDir::separator());
 
     QString filename;
-    auto *pl = getIApp()->getPlugins()->getPluginByStatePtr(L);
+    auto *pl = getApp()->getPlugins()->getPluginByStatePtr(L);
     if (pl == nullptr)
     {
         return luaL_error(L, "searcherAbsolute: internal error: no plugin?");
@@ -348,7 +348,7 @@ int searcherRelative(lua_State *L)
 
 int g_print(lua_State *L)
 {
-    auto *pl = getIApp()->getPlugins()->getPluginByStatePtr(L);
+    auto *pl = getApp()->getPlugins()->getPluginByStatePtr(L);
     if (pl == nullptr)
     {
         luaL_error(L, "c2_print: internal error: no plugin?");

src/controllers/plugins/Plugin.cpp

@@ -197,7 +197,7 @@ bool Plugin::registerCommand(const QString &name, const QString &functionName)
         return false;
     }
 
-    auto ok = getIApp()->getCommands()->registerPluginCommand(name);
+    auto ok = getApp()->getCommands()->registerPluginCommand(name);
     if (!ok)
     {
         return false;

src/controllers/plugins/PluginController.cpp

@@ -35,10 +35,8 @@ PluginController::PluginController(const Paths &paths_)
 {
 }
 
-void PluginController::initialize(Settings &settings, const Paths &paths)
+void PluginController::initialize(Settings &settings)
 {
-    (void)paths;
-
     // actuallyInitialize will be called by this connection
     settings.pluginsEnabled.connect([this](bool enabled) {
         if (enabled)
@@ -354,7 +352,7 @@ bool PluginController::reload(const QString &id)
     }
     for (const auto &[cmd, _] : it->second->ownedCommands)
     {
-        getIApp()->getCommands()->unregisterPluginCommand(cmd);
+        getApp()->getCommands()->unregisterPluginCommand(cmd);
     }
     it->second->ownedCommands.clear();
     QDir loadDir = it->second->loadDirectory_;

src/controllers/plugins/PluginController.hpp

@@ -2,7 +2,6 @@
 
 #ifdef CHATTERINO_HAVE_PLUGINS
 
-#    include "common/Singleton.hpp"
 #    include "controllers/commands/CommandContext.hpp"
 #    include "controllers/plugins/Plugin.hpp"
 
@@ -24,14 +23,14 @@ namespace chatterino {
 
 class Paths;
 
-class PluginController : public Singleton
+class PluginController
 {
     const Paths &paths;
 
 public:
     explicit PluginController(const Paths &paths_);
 
-    void initialize(Settings &settings, const Paths &paths) override;
+    void initialize(Settings &settings);
 
     QString tryExecPluginCommand(const QString &commandName,
                                  const CommandContext &ctx);

src/controllers/plugins/api/ChannelRef.cpp

@@ -174,7 +174,7 @@ int ChannelRef::send_message(lua_State *L)
     text = text.replace('\n', ' ');
     if (execcmds)
     {
-        text = getIApp()->getCommands()->execCommand(text, that, false);
+        text = getApp()->getCommands()->execCommand(text, that, false);
     }
     that->sendMessage(text);
     return 0;
@@ -300,7 +300,7 @@ int ChannelRef::get_by_name(lua_State *L)
         lua_pushnil(L);
         return 1;
     }
-    auto chn = getIApp()->getTwitchAbstract()->getChannelOrEmpty(name);
+    auto chn = getApp()->getTwitchAbstract()->getChannelOrEmpty(name);
     lua::push(L, chn);
     return 1;
 }
@@ -324,7 +324,7 @@ int ChannelRef::get_by_twitch_id(lua_State *L)
         lua_pushnil(L);
         return 1;
     }
-    auto chn = getIApp()->getTwitch()->getChannelOrEmptyByID(id);
+    auto chn = getApp()->getTwitch()->getChannelOrEmptyByID(id);
 
     lua::push(L, chn);
     return 1;

src/controllers/plugins/api/HTTPRequest.cpp

@@ -309,7 +309,7 @@ int HTTPRequest::create(lua_State *L)
             L, "cannot get method (1st argument of HTTPRequest.create, "
                "expected a string)");
     }
-    auto *pl = getIApp()->getPlugins()->getPluginByStatePtr(L);
+    auto *pl = getApp()->getPlugins()->getPluginByStatePtr(L);
     if (!pl->hasHTTPPermissionFor(parsedurl))
     {
         return luaL_error(