#pragma once

#include <memory>
#include "gfx/shader.hpp"
#include "game/world.hpp"
#include "game/sector.hpp"
#include "game/meshinstance.hpp"

namespace gfx
{
	struct DrawSectorParams
	{
		size_t draw_id;
		const game::Sector* sector;
		const game::Portal* entry_portal;
		glm::vec4 clip_plane;
		collision::AABB2 screen_aabb;
		size_t recursion;
		glm::mat4 view;
		glm::mat4 view_proj;
		glm::vec3 eye;
	};

	struct SectorShader
	{
		std::unique_ptr<Shader> shader;
		size_t setup_sector = 0;
	};

	class Renderer
	{
	public:
		Renderer();

		void Begin(size_t width, size_t height);

		void DrawWorld(
			const game::World& world,
			size_t sector_idx,
			const glm::vec3& eye,
			const glm::vec3& dir,
			const glm::vec3& up,
			float aspect,
			float fov);

	private:
		SectorShader sector_shader_;
		SectorShader portal_shader_;
		SectorShader mesh_shader_;

		std::shared_ptr<VertexArray> portal_vao_;
		void SetupPortalVAO();

		size_t max_portal_recursion_ = 10;

		// Minimum distance to portal mesh from eye
		// If the distance is smaller, portal plane is shifted to avoid clipping by near plane
		float min_portal_distance_;

		glm::mat4 proj_;
		size_t last_sector_id;
		const Shader* current_shader_;

		void UnreadyShaders();
		void SetupSectorShader(const DrawSectorParams& params, SectorShader& sshader);

		void DrawSector(const DrawSectorParams& params);
		void DrawPortal(const DrawSectorParams& params, const game::Portal& portal);
		
		static bool ComputeQuadScreenAABB(const glm::vec3* verts, const glm::mat4 view_proj, collision::AABB2& aabb);
		void DrawPortalPlane(const DrawSectorParams& params, const game::Portal& portal, const glm::mat4& trans, bool clear_depth);

		void DrawMeshInstance(const DrawSectorParams& params, const game::MeshInstance& mesh_instance, const glm::mat4& model);

	};

}