From ff6aec9f700de8b9332767d982ea89bd4ebf3e18 Mon Sep 17 00:00:00 2001
From: BlackMATov <blackmatov@gmail.com>
Date: Sun, 12 Jan 2020 01:47:06 +0700
Subject: [PATCH] utils: variadic module::is_initialized and module::shutdown

---
 headers/enduro2d/utils/module.hpp             | 10 +++----
 sources/enduro2d/core/engine.cpp              |  8 ++---
 .../high/widgets/hierarchy_widget.cpp         |  6 +---
 .../high/widgets/inspector_widget.cpp         |  6 +---
 untests/sources/untests_utils/module.cpp      | 29 +++++++++++++++++++
 5 files changed, 39 insertions(+), 20 deletions(-)

diff --git a/headers/enduro2d/utils/module.hpp b/headers/enduro2d/utils/module.hpp
index 75aa3772..315ec1c8 100644
--- a/headers/enduro2d/utils/module.hpp
+++ b/headers/enduro2d/utils/module.hpp
@@ -80,16 +80,14 @@ namespace e2d::modules
         return module<BaseT>::template initialize<ImplT>(std::forward<Args>(args)...);
     }
 
-    template < typename ImplT >
+    template < typename... ImplTs >
     void shutdown() noexcept {
-        using BaseT = typename ImplT::base_type;
-        module<BaseT>::shutdown();
+        return (... , module<typename ImplTs::base_type>::shutdown());
     }
 
-    template < typename ImplT >
+    template < typename... ImplTs >
     bool is_initialized() noexcept {
-        using BaseT = typename ImplT::base_type;
-        return module<BaseT>::is_initialized();
+        return (... && module<typename ImplTs::base_type>::is_initialized());
     }
 
     template < typename ImplT >
diff --git a/sources/enduro2d/core/engine.cpp b/sources/enduro2d/core/engine.cpp
index 27e207fc..c7faa61b 100644
--- a/sources/enduro2d/core/engine.cpp
+++ b/sources/enduro2d/core/engine.cpp
@@ -23,10 +23,10 @@ namespace
     using namespace e2d;
 
     template < typename Module, typename... Args >
-    void safe_module_initialize(Args&&... args) {
-        if ( !modules::is_initialized<Module>() ) {
-            modules::initialize<Module>(std::forward<Args>(args)...);
-        }
+    Module& safe_module_initialize(Args&&... args) {
+        return modules::is_initialized<Module>()
+            ? modules::instance<Module>()
+            : modules::initialize<Module>(std::forward<Args>(args)...);
     }
 
     void safe_register_predef_path(
diff --git a/sources/enduro2d/high/widgets/hierarchy_widget.cpp b/sources/enduro2d/high/widgets/hierarchy_widget.cpp
index 55ebdaf7..ac761854 100644
--- a/sources/enduro2d/high/widgets/hierarchy_widget.cpp
+++ b/sources/enduro2d/high/widgets/hierarchy_widget.cpp
@@ -86,11 +86,7 @@ namespace e2d::dbgui_widgets
     }
 
     bool hierarchy_widget::show() {
-        if ( !modules::is_initialized<editor>() ) {
-            return false;
-        }
-        
-        if ( !modules::is_initialized<world>() ) {
+        if ( !modules::is_initialized<editor, world>() ) {
             return false;
         }
 
diff --git a/sources/enduro2d/high/widgets/inspector_widget.cpp b/sources/enduro2d/high/widgets/inspector_widget.cpp
index 9fd98be7..deced669 100644
--- a/sources/enduro2d/high/widgets/inspector_widget.cpp
+++ b/sources/enduro2d/high/widgets/inspector_widget.cpp
@@ -18,11 +18,7 @@ namespace e2d::dbgui_widgets
     }
 
     bool inspector_widget::show() {
-        if ( !modules::is_initialized<editor>() ) {
-            return false;
-        }
-
-        if ( !modules::is_initialized<inspector>() ) {
+        if ( !modules::is_initialized<editor, inspector>() ) {
             return false;
         }
 
diff --git a/untests/sources/untests_utils/module.cpp b/untests/sources/untests_utils/module.cpp
index 25ffa565..5565d8c4 100644
--- a/untests/sources/untests_utils/module.cpp
+++ b/untests/sources/untests_utils/module.cpp
@@ -26,6 +26,12 @@ namespace
     private:
         u32 m_;
     };
+
+    class empty_module : public module<empty_module> {
+    };
+
+    class empty_module_impl : public empty_module {
+    };
 }
 
 TEST_CASE("module") {
@@ -92,4 +98,27 @@ TEST_CASE("module") {
         REQUIRE_THROWS_AS(modules::instance<mul_module>(), module_not_initialized);
         REQUIRE_THROWS_AS(modules::instance<mul_module_impl>(), module_not_initialized);
     }
+    {
+        REQUIRE_FALSE(modules::is_initialized<mul_module>());
+        REQUIRE_FALSE(modules::is_initialized<empty_module>());
+        REQUIRE_FALSE(modules::is_initialized<mul_module, empty_module>());
+
+        REQUIRE_NOTHROW(modules::initialize<mul_module_impl>(3));
+
+        REQUIRE(modules::is_initialized<mul_module>());
+        REQUIRE_FALSE(modules::is_initialized<empty_module>());
+        REQUIRE_FALSE(modules::is_initialized<mul_module, empty_module>());
+
+        REQUIRE_NOTHROW(modules::initialize<empty_module_impl>());
+
+        REQUIRE(modules::is_initialized<mul_module>());
+        REQUIRE(modules::is_initialized<empty_module>());
+        REQUIRE(modules::is_initialized<mul_module, empty_module>());
+
+        REQUIRE_NOTHROW(modules::shutdown<empty_module, mul_module_impl>());
+
+        REQUIRE_FALSE(modules::is_initialized<mul_module>());
+        REQUIRE_FALSE(modules::is_initialized<empty_module>());
+        REQUIRE_FALSE(modules::is_initialized<mul_module, empty_module>());
+    }
 }