#include <gtest/gtest.h>
#include <XCEngine/Scene/SceneManager.h>
#include <XCEngine/Components/GameObject.h>

using namespace XCEngine::Components;

namespace {

class SceneManagerTest : public ::testing::Test {
protected:
    void TearDown() override {
        auto scenes = SceneManager::Get().GetAllScenes();
        for (auto* scene : scenes) {
            SceneManager::Get().UnloadScene(scene);
        }
    }
};

TEST(SceneManager_Test, Get_ReturnsSingleton) {
    SceneManager& sm1 = SceneManager::Get();
    SceneManager& sm2 = SceneManager::Get();
    
    EXPECT_EQ(&sm1, &sm2);
}

TEST(SceneManager_Test, CreateScene_Simple) {
    SceneManager& sm = SceneManager::Get();
    
    Scene* scene = sm.CreateScene("TestScene");
    
    EXPECT_NE(scene, nullptr);
    EXPECT_EQ(scene->GetName(), "TestScene");
}

TEST(SceneManager_Test, CreateScene_AssignsName) {
    SceneManager& sm = SceneManager::Get();
    
    Scene* scene = sm.CreateScene("MyScene");
    
    EXPECT_EQ(scene->GetName(), "MyScene");
}

TEST(SceneManager_Test, GetScene_Exists) {
    SceneManager& sm = SceneManager::Get();
    sm.CreateScene("TestScene");
    
    Scene* found = sm.GetScene("TestScene");
    
    EXPECT_NE(found, nullptr);
    EXPECT_EQ(found->GetName(), "TestScene");
}

TEST(SceneManager_Test, GetScene_NotExists) {
    SceneManager& sm = SceneManager::Get();
    
    Scene* found = sm.GetScene("NonExistent");
    
    EXPECT_EQ(found, nullptr);
}

TEST(SceneManager_Test, GetAllScenes_ReturnsAll) {
    SceneManager& sm = SceneManager::Get();
    sm.CreateScene("Scene1");
    sm.CreateScene("Scene2");
    sm.CreateScene("Scene3");
    
    auto scenes = sm.GetAllScenes();
    
    EXPECT_EQ(scenes.size(), 3u);
}

TEST(SceneManager_Test, SetActiveScene) {
    SceneManager& sm = SceneManager::Get();
    Scene* scene1 = sm.CreateScene("Scene1");
    Scene* scene2 = sm.CreateScene("Scene2");
    
    sm.SetActiveScene(scene2);
    
    EXPECT_EQ(sm.GetActiveScene(), scene2);
}

TEST(SceneManager_Test, SetActiveScene_ByName) {
    SceneManager& sm = SceneManager::Get();
    sm.CreateScene("Scene1");
    sm.CreateScene("Scene2");
    
    sm.SetActiveScene("Scene2");
    
    EXPECT_EQ(sm.GetActiveScene()->GetName(), "Scene2");
}

TEST(SceneManager_Test, GetActiveScene_InitiallyFirst) {
    SceneManager& sm = SceneManager::Get();
    auto scenes = sm.GetAllScenes();
    for (auto* scene : scenes) {
        sm.UnloadScene(scene);
    }
    
    Scene* scene1 = sm.CreateScene("First");
    
    EXPECT_EQ(sm.GetActiveScene(), scene1);
}

TEST(SceneManager_Test, UnloadScene) {
    SceneManager& sm = SceneManager::Get();
    Scene* scene = sm.CreateScene("ToUnload");
    
    sm.UnloadScene(scene);
    
    EXPECT_EQ(sm.GetScene("ToUnload"), nullptr);
}

TEST(SceneManager_Test, UnloadScene_ByName) {
    SceneManager& sm = SceneManager::Get();
    sm.CreateScene("ToUnload");
    
    sm.UnloadScene("ToUnload");
    
    EXPECT_EQ(sm.GetScene("ToUnload"), nullptr);
}

TEST(SceneManager_Test, OnSceneLoaded_Event) {
    SceneManager& sm = SceneManager::Get();
    bool eventFired = false;
    sm.OnSceneLoaded().Subscribe([&eventFired](Scene*) {
        eventFired = true;
    });
    
    sm.CreateScene("TestScene");
    
    EXPECT_TRUE(eventFired);
}

TEST(SceneManager_Test, OnActiveSceneChanged_Event) {
    SceneManager& sm = SceneManager::Get();
    Scene* scene1 = sm.CreateScene("Scene1");
    Scene* scene2 = sm.CreateScene("Scene2");
    
    bool eventFired = false;
    sm.OnActiveSceneChanged().Subscribe([&eventFired](Scene*) {
        eventFired = true;
    });
    
    sm.SetActiveScene(scene2);
    
    EXPECT_TRUE(eventFired);
}

TEST(SceneManager_Test, CreateScene_MultipleScenes) {
    SceneManager& sm = SceneManager::Get();
    
    Scene* scene1 = sm.CreateScene("Scene1");
    Scene* scene2 = sm.CreateScene("Scene2");
    Scene* scene3 = sm.CreateScene("Scene3");
    
    EXPECT_NE(scene1, scene2);
    EXPECT_NE(scene2, scene3);
    EXPECT_NE(scene1, scene3);
}

TEST(SceneManager_Test, SetActiveScene_ToNullptr) {
    SceneManager& sm = SceneManager::Get();
    Scene* scene1 = sm.CreateScene("Scene1");
    Scene* scene2 = sm.CreateScene("Scene2");
    sm.SetActiveScene(scene2);
    
    sm.SetActiveScene(nullptr);
    
    EXPECT_EQ(sm.GetActiveScene(), nullptr);
}

} // namespace