#pragma once

#include "GLFunctions.hpp"

#include <glm/glm.hpp>
#include <vector>

namespace planetarium {

// -----------------------------------------------------------------------
// Mesh
//
// Owns a VAO/VBO/(optional)EBO describing an interleaved
// position+normal+uv vertex stream, plus static factory methods that
// procedurally build a few common primitive shapes (spheres, rings,
// circles) so a project has no dependency on external model files.
// -----------------------------------------------------------------------
struct Vertex {
    glm::vec3 position;
    glm::vec3 normal;
    glm::vec2 uv;
};

class Mesh {
public:
    Mesh() = default;
    ~Mesh();

    Mesh(const Mesh&) = delete;
    Mesh& operator=(const Mesh&) = delete;
    Mesh(Mesh&& other) noexcept;
    Mesh& operator=(Mesh&& other) noexcept;

    void upload(const std::vector<Vertex>& vertices, const std::vector<unsigned int>& indices);
    void uploadLineStrip(const std::vector<glm::vec3>& points);
    void draw() const;
    void drawLineStrip() const;

    static Mesh createUVSphere(int stacks, int slices);
    static Mesh createRing(float innerRadius, float outerRadius, int segments);
    static Mesh createOrbitCircle(int segments);  // unit circle in XZ

private:
    void release();

    GLuint vao_ = 0;
    GLuint vbo_ = 0;
    GLuint ebo_ = 0;
    GLsizei indexCount_ = 0;
    GLsizei vertexCount_ = 0;
    bool isLineStrip_ = false;
};

}  // namespace planetarium