#pragma once

#include "ZLMath.h"
#include "Renderer.h"
#include "TextureManager.h"
#include <vector>
#include <chrono>
#include <iostream>
#include <string>
#include <array>
#include <numeric>
#include <random>
#include <algorithm>

namespace ZL {

    struct Triangle
    {
        std::array<Vector3f, 3> data;

        Triangle(Vector3f p1, Vector3f p2, Vector3f p3)
            : data{ p1, p2, p3 }
        {
        }
    };

    class PerlinNoise {
        std::vector<int> p;
    public:
        PerlinNoise();
        PerlinNoise(uint64_t seed);

        float fade(float t);
        float lerp(float t, float a, float b);
        float grad(int hash, float x, float y, float z);

        float noise(float x, float y, float z);

        float getSurfaceHeight(Vector3f pos);
    };


	class PlanetObject {
	private:
        PerlinNoise perlin;
        PerlinNoise colorPerlin;
		void prepareDrawData();
		VertexDataStruct planetMesh;
		VertexRenderStruct planetRenderStruct;

        std::shared_ptr<Texture> sandTexture;

	public:
		PlanetObject();

		void init();

		void update(float deltaTimeMs);

		void draw(Renderer& renderer);

        bool planetIsFar(const Vector3f& shipPosition);


	private:
		bool drawDataDirty = true;

        std::vector<Triangle> subdivideTriangles(const std::vector<Triangle>& inputTriangles);
        Vector3f calculateSurfaceNormal(Vector3f p_sphere);
        VertexDataStruct trianglesToVertices(const std::vector<Triangle>& triangles);
        VertexDataStruct generateSphere(int subdivisions);
	};

} // namespace ZL