#include <Nazara/Core.hpp>
#include <Nazara/Platform.hpp>
#include <Nazara/Graphics.hpp>
#include <Nazara/Renderer.hpp>
#include <Nazara/Shader.hpp>
#include <Nazara/Shader/SpirvConstantCache.hpp>
#include <Nazara/Shader/SpirvPrinter.hpp>
#include <Nazara/Utility.hpp>
#include <array>
#include <iostream>

int main()
{
	std::filesystem::path resourceDir = "resources";
	if (!std::filesystem::is_directory(resourceDir) && std::filesystem::is_directory(".." / resourceDir))
		resourceDir = ".." / resourceDir;

	Nz::Renderer::Config rendererConfig;
	std::cout << "Run using Vulkan? (y/n)" << std::endl;
	if (std::getchar() == 'y')
		rendererConfig.preferredAPI = Nz::RenderAPI::Vulkan;
	else
		rendererConfig.preferredAPI = Nz::RenderAPI::OpenGL;

	Nz::Modules<Nz::Graphics> nazara(rendererConfig);

	Nz::RenderWindow window;

	Nz::MeshParams meshParams;
	meshParams.center = true;
	meshParams.storage = Nz::DataStorage::Software;
	meshParams.matrix = Nz::Matrix4f::Rotate(Nz::EulerAnglesf(0.f, -90.f, 0.f)) * Nz::Matrix4f::Scale(Nz::Vector3f(0.002f));
	meshParams.vertexDeclaration = Nz::VertexDeclaration::Get(Nz::VertexLayout::XYZ_UV);

	std::shared_ptr<Nz::RenderDevice> device = Nz::Graphics::Instance()->GetRenderDevice();

	std::string windowTitle = "Graphics Test";
	if (!window.Create(device, Nz::VideoMode(1920, 1080, 32), windowTitle))
	{
		std::cout << "Failed to create Window" << std::endl;
		return __LINE__;
	}

	std::shared_ptr<Nz::Mesh> spaceshipMesh = Nz::Mesh::LoadFromFile(resourceDir / "Spaceship/spaceship.obj", meshParams);
	if (!spaceshipMesh)
	{
		NazaraError("Failed to load model");
		return __LINE__;
	}

	std::shared_ptr<Nz::GraphicalMesh> gfxMesh = std::make_shared<Nz::GraphicalMesh>(*spaceshipMesh);

	// Texture
	std::shared_ptr<Nz::Image> diffuseImage = Nz::Image::LoadFromFile(resourceDir / "Spaceship/Texture/diffuse.png");
	if (!diffuseImage || !diffuseImage->Convert(Nz::PixelFormat::RGBA8_SRGB))
	{
		NazaraError("Failed to load image");
		return __LINE__;
	}

	Nz::TextureParams texParams;
	texParams.renderDevice = device;
	texParams.loadFormat = Nz::PixelFormat::RGBA8_SRGB;

	std::shared_ptr<Nz::Material> material = std::make_shared<Nz::Material>(Nz::BasicMaterial::GetSettings());
	material->EnableDepthBuffer(true);
	material->EnableFaceCulling(true);

	Nz::BasicMaterial basicMat(*material);
	basicMat.EnableAlphaTest(false);
	basicMat.SetAlphaMap(Nz::Texture::LoadFromFile(resourceDir / "alphatile.png", texParams));
	basicMat.SetDiffuseMap(Nz::Texture::LoadFromFile(resourceDir / "Spaceship/Texture/diffuse.png", texParams));

	Nz::Model model(std::move(gfxMesh));
	for (std::size_t i = 0; i < model.GetSubMeshCount(); ++i)
		model.SetMaterial(i, material);

	Nz::Vector2ui windowSize = window.GetSize();

	Nz::ViewerInstance viewerInstance;
	viewerInstance.UpdateTargetSize(Nz::Vector2f(window.GetSize()));
	viewerInstance.UpdateProjViewMatrices(Nz::Matrix4f::Perspective(Nz::DegreeAnglef(70.f), float(windowSize.x) / windowSize.y, 0.1f, 1000.f), Nz::Matrix4f::Translate(Nz::Vector3f::Backward() * 1));

	Nz::WorldInstance modelInstance;
	modelInstance.UpdateWorldMatrix(Nz::Matrix4f::Translate(Nz::Vector3f::Forward() * 2 + Nz::Vector3f::Left()));

	Nz::WorldInstance modelInstance2;
	modelInstance2.UpdateWorldMatrix(Nz::Matrix4f::Translate(Nz::Vector3f::Forward() * 2 + Nz::Vector3f::Right()));

	Nz::RenderWindowImpl* windowImpl = window.GetImpl();

	Nz::Vector3f viewerPos = Nz::Vector3f::Zero();

	Nz::EulerAnglesf camAngles(0.f, 0.f, 0.f);
	Nz::Quaternionf camQuat(camAngles);

	window.EnableEventPolling(true);

	Nz::Clock updateClock;
	Nz::Clock secondClock;
	unsigned int fps = 0;

	Nz::Mouse::SetRelativeMouseMode(true);

	bool updateMat = false;
	while (window.IsOpen())
	{
		Nz::WindowEvent event;
		while (window.PollEvent(&event))
		{
			switch (event.type)
			{
				case Nz::WindowEventType::Quit:
					window.Close();
					break;

				case Nz::WindowEventType::KeyPressed:
					if (event.key.virtualKey == Nz::Keyboard::VKey::A)
					{
						basicMat.EnableAlphaTest(!basicMat.IsAlphaTestEnabled());
						updateMat = true;
					}

					break;

				case Nz::WindowEventType::MouseMoved: // La souris a bougé
				{
					// Gestion de la caméra free-fly (Rotation)
					float sensitivity = 0.3f; // Sensibilité de la souris

					// On modifie l'angle de la caméra grâce au déplacement relatif sur X de la souris
					camAngles.yaw = camAngles.yaw - event.mouseMove.deltaX * sensitivity;
					camAngles.yaw.Normalize();

					// Idem, mais pour éviter les problèmes de calcul de la matrice de vue, on restreint les angles
					camAngles.pitch = Nz::Clamp(camAngles.pitch - event.mouseMove.deltaY*sensitivity, -89.f, 89.f);

					camQuat = camAngles;
					break;
				}

				case Nz::WindowEventType::Resized:
				{
					Nz::Vector2ui windowSize = window.GetSize();
					viewerInstance.UpdateProjectionMatrix(Nz::Matrix4f::Perspective(Nz::DegreeAnglef(70.f), float(windowSize.x) / windowSize.y, 0.1f, 1000.f));
					viewerInstance.UpdateTargetSize(Nz::Vector2f(windowSize));
					break;
				}

				default:
					break;
			}
		}

		if (updateClock.GetMilliseconds() > 1000 / 60)
		{
			float cameraSpeed = 2.f * updateClock.GetSeconds();
			updateClock.Restart();

			if (Nz::Keyboard::IsKeyPressed(Nz::Keyboard::VKey::Up) || Nz::Keyboard::IsKeyPressed(Nz::Keyboard::VKey::Z))
				viewerPos += camQuat * Nz::Vector3f::Forward() * cameraSpeed;

			// Si la flèche du bas ou la touche S est pressée, on recule
			if (Nz::Keyboard::IsKeyPressed(Nz::Keyboard::VKey::Down) || Nz::Keyboard::IsKeyPressed(Nz::Keyboard::VKey::S))
				viewerPos += camQuat * Nz::Vector3f::Backward() * cameraSpeed;

			// Etc...
			if (Nz::Keyboard::IsKeyPressed(Nz::Keyboard::VKey::Left) || Nz::Keyboard::IsKeyPressed(Nz::Keyboard::VKey::Q))
				viewerPos += camQuat * Nz::Vector3f::Left() * cameraSpeed;

			// Etc...
			if (Nz::Keyboard::IsKeyPressed(Nz::Keyboard::VKey::Right) || Nz::Keyboard::IsKeyPressed(Nz::Keyboard::VKey::D))
				viewerPos += camQuat * Nz::Vector3f::Right() * cameraSpeed;

			// Majuscule pour monter, notez l'utilisation d'une direction globale (Non-affectée par la rotation)
			if (Nz::Keyboard::IsKeyPressed(Nz::Keyboard::VKey::LShift) || Nz::Keyboard::IsKeyPressed(Nz::Keyboard::VKey::RShift))
				viewerPos += Nz::Vector3f::Up() * cameraSpeed;

			// Contrôle (Gauche ou droite) pour descendre dans l'espace global, etc...
			if (Nz::Keyboard::IsKeyPressed(Nz::Keyboard::VKey::LControl) || Nz::Keyboard::IsKeyPressed(Nz::Keyboard::VKey::RControl))
				viewerPos += Nz::Vector3f::Down() * cameraSpeed;
		}

		Nz::RenderFrame frame = windowImpl->Acquire();
		if (!frame)
			continue;

		Nz::UploadPool& uploadPool = frame.GetUploadPool();

		viewerInstance.UpdateViewMatrix(Nz::Matrix4f::ViewMatrix(viewerPos, camAngles));

		frame.Execute([&](Nz::CommandBufferBuilder& builder)
		{
			builder.BeginDebugRegion("UBO Update", Nz::Color::Yellow);
			{
				builder.PreTransferBarrier();

				viewerInstance.UpdateBuffers(uploadPool, builder);
				modelInstance.UpdateBuffers(uploadPool, builder);
				modelInstance2.UpdateBuffers(uploadPool, builder);

				updateMat = material->Update(frame, builder) || updateMat;

				builder.PostTransferBarrier();
			}
			builder.EndDebugRegion();
		}, Nz::QueueType::Transfer);

		frame.Execute([&](Nz::CommandBufferBuilder& builder)
		{
			Nz::Recti renderRect(0, 0, window.GetSize().x, window.GetSize().y);

			Nz::CommandBufferBuilder::ClearValues clearValues[2];
			clearValues[0].color = Nz::Color::Black;
			clearValues[1].depth = 1.f;
			clearValues[1].stencil = 0;

			builder.BeginDebugRegion("Main window rendering", Nz::Color::Green);
			{
				builder.BeginRenderPass(windowImpl->GetFramebuffer(frame.GetFramebufferIndex()), windowImpl->GetRenderPass(), renderRect, { clearValues[0], clearValues[1] });
				{
					builder.SetScissor(Nz::Recti{ 0, 0, int(windowSize.x), int(windowSize.y) });
					builder.SetViewport(Nz::Recti{ 0, 0, int(windowSize.x), int(windowSize.y) });
					builder.BindShaderBinding(Nz::Graphics::ViewerBindingSet, viewerInstance.GetShaderBinding());

					for (Nz::WorldInstance& instance : { std::ref(modelInstance), std::ref(modelInstance2) })
					{
						builder.BindShaderBinding(Nz::Graphics::WorldBindingSet, instance.GetShaderBinding());

						for (std::size_t i = 0; i < model.GetSubMeshCount(); ++i)
						{
							builder.BindIndexBuffer(model.GetIndexBuffer(i).get());
							builder.BindVertexBuffer(0, model.GetVertexBuffer(i).get());
							builder.BindPipeline(*model.GetRenderPipeline(i));
							builder.BindShaderBinding(Nz::Graphics::MaterialBindingSet, model.GetMaterial(i)->GetShaderBinding());

							builder.DrawIndexed(model.GetIndexCount(i));
						}
					}
				}
				builder.EndRenderPass();
			}
			builder.EndDebugRegion();
		}, Nz::QueueType::Graphics);

		frame.Present();

		window.Display();

		// On incrémente le compteur de FPS improvisé
		fps++;

		if (secondClock.GetMilliseconds() >= 1000) // Toutes les secondes
		{
			// Et on insère ces données dans le titre de la fenêtre
			window.SetTitle(windowTitle + " - " + Nz::NumberToString(fps) + " FPS");

			/*
			Note: En C++11 il est possible d'insérer de l'Unicode de façon standard, quel que soit l'encodage du fichier,
			via quelque chose de similaire à u8"Cha\u00CEne de caract\u00E8res".
			Cependant, si le code source est encodé en UTF-8 (Comme c'est le cas dans ce fichier),
			cela fonctionnera aussi comme ceci : "Chaîne de caractères".
			*/

			// Et on réinitialise le compteur de FPS
			fps = 0;

			// Et on relance l'horloge pour refaire ça dans une seconde
			secondClock.Restart();
		}
	}

	return EXIT_SUCCESS;
}