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

using namespace XCEngine::Components;

namespace {

class TestComponent : public Component {
public:
    TestComponent() = default;
    explicit TestComponent(const std::string& name) : m_customName(name) {}

    std::string GetName() const override {
        return m_customName.empty() ? "TestComponent" : m_customName;
    }

    bool m_awakeCalled = false;
    bool m_updateCalled = false;

    void Awake() override { m_awakeCalled = true; }
    void Update(float deltaTime) override { m_updateCalled = true; }

private:
    std::string m_customName;
};

class SceneTest : public ::testing::Test {
protected:
    void SetUp() override {
        testScene = std::make_unique<Scene>("TestScene");
    }

    std::unique_ptr<Scene> testScene;
};

TEST(Scene_Test, DefaultConstructor_DefaultName) {
    Scene s;
    
    EXPECT_EQ(s.GetName(), "Untitled");
}

TEST(Scene_Test, NamedConstructor) {
    Scene s("MyScene");
    
    EXPECT_EQ(s.GetName(), "MyScene");
}

TEST_F(SceneTest, CreateGameObject_Simple) {
    GameObject* go = testScene->CreateGameObject("TestObject");
    
    EXPECT_NE(go, nullptr);
    EXPECT_EQ(go->GetName(), "TestObject");
}

TEST_F(SceneTest, CreateGameObject_WithParent) {
    GameObject* parent = testScene->CreateGameObject("Parent");
    GameObject* child = testScene->CreateGameObject("Child", parent);
    
    EXPECT_NE(child, nullptr);
    EXPECT_EQ(child->GetParent(), parent);
}

TEST_F(SceneTest, CreateGameObject_AssignsID) {
    GameObject* go1 = testScene->CreateGameObject("Object1");
    GameObject* go2 = testScene->CreateGameObject("Object2");
    
    EXPECT_NE(go1->GetID(), GameObject::INVALID_ID);
    EXPECT_NE(go2->GetID(), GameObject::INVALID_ID);
    EXPECT_NE(go1->GetID(), go2->GetID());
}

TEST_F(SceneTest, CreateGameObject_AddsToRoot) {
    GameObject* go = testScene->CreateGameObject("RootObject");
    
    auto roots = testScene->GetRootGameObjects();
    
    EXPECT_EQ(roots.size(), 1u);
    EXPECT_EQ(roots[0], go);
}

TEST_F(SceneTest, DestroyGameObject_Simple) {
    GameObject* go = testScene->CreateGameObject("TestObject");
    
    testScene->DestroyGameObject(go);
    
    EXPECT_EQ(testScene->Find("TestObject"), nullptr);
}

TEST_F(SceneTest, DestroyGameObject_WithChildren) {
    GameObject* parent = testScene->CreateGameObject("Parent");
    testScene->CreateGameObject("Child", parent);
    
    testScene->DestroyGameObject(parent);
    
    EXPECT_EQ(testScene->Find("Parent"), nullptr);
    EXPECT_EQ(testScene->Find("Child"), nullptr);
}

TEST_F(SceneTest, Find_Exists) {
    testScene->CreateGameObject("FindMe");
    
    GameObject* found = testScene->Find("FindMe");
    
    EXPECT_NE(found, nullptr);
    EXPECT_EQ(found->GetName(), "FindMe");
}

TEST_F(SceneTest, Find_NotExists) {
    GameObject* found = testScene->Find("NonExistent");
    
    EXPECT_EQ(found, nullptr);
}

TEST_F(SceneTest, GetRootGameObjects_ReturnsTopLevel) {
    GameObject* parent = testScene->CreateGameObject("Parent");
    testScene->CreateGameObject("Child", parent);
    
    auto roots = testScene->GetRootGameObjects();
    
    EXPECT_EQ(roots.size(), 1u);
    EXPECT_EQ(roots[0], parent);
}

TEST(Scene_Test, GetRootGameObjects_EmptyScene) {
    Scene emptyScene;
    
    auto roots = emptyScene.GetRootGameObjects();
    
    EXPECT_EQ(roots.size(), 0u);
}

TEST_F(SceneTest, Update_UpdatesActiveObjects) {
    GameObject* go = testScene->CreateGameObject("TestObject");
    TestComponent* comp = go->AddComponent<TestComponent>();
    
    testScene->Update(0.016f);
    
    EXPECT_TRUE(comp->m_updateCalled);
}

TEST_F(SceneTest, Update_SkipsInactiveObjects) {
    GameObject* go = testScene->CreateGameObject("InactiveObject");
    TestComponent* comp = go->AddComponent<TestComponent>();
    go->SetActive(false);
    
    testScene->Update(0.016f);
    
    EXPECT_FALSE(comp->m_updateCalled);
}

TEST(Scene_Test, IsActive_DefaultTrue) {
    Scene s;
    
    EXPECT_TRUE(s.IsActive());
}

TEST(Scene_Test, SetActive) {
    Scene s;
    s.SetActive(false);
    
    EXPECT_FALSE(s.IsActive());
}

TEST_F(SceneTest, FindObjectOfType) {
    GameObject* go = testScene->CreateGameObject("TestObject");
    go->AddComponent<TestComponent>();
    
    TestComponent* found = testScene->FindObjectOfType<TestComponent>();
    
    EXPECT_NE(found, nullptr);
}

TEST_F(SceneTest, FindObjectsOfType) {
    GameObject* go1 = testScene->CreateGameObject("Object1");
    GameObject* go2 = testScene->CreateGameObject("Object2");
    go1->AddComponent<TestComponent>();
    go2->AddComponent<TestComponent>();
    
    auto found = testScene->FindObjectsOfType<TestComponent>();
    
    EXPECT_EQ(found.size(), 2u);
}

TEST_F(SceneTest, FindGameObjectWithTag) {
    GameObject* go = testScene->CreateGameObject("MyTag");
    
    GameObject* found = testScene->FindGameObjectWithTag("MyTag");
    
    EXPECT_NE(found, nullptr);
}

TEST_F(SceneTest, OnGameObjectCreated_Event) {
    bool eventFired = false;
    testScene->OnGameObjectCreated().Subscribe([&eventFired](GameObject*) {
        eventFired = true;
    });
    
    testScene->CreateGameObject("TestObject");
    
    EXPECT_TRUE(eventFired);
}

TEST_F(SceneTest, OnGameObjectDestroyed_Event) {
    bool eventFired = false;
    testScene->OnGameObjectDestroyed().Subscribe([&eventFired](GameObject*) {
        eventFired = true;
    });
    
    GameObject* go = testScene->CreateGameObject("TestObject");
    testScene->DestroyGameObject(go);
    
    EXPECT_TRUE(eventFired);
}

} // namespace