package renderer;

import org.lwjgl.system.MemoryUtil;

import java.nio.FloatBuffer;

import static org.lwjgl.opengl.GL30.*;
import static org.lwjgl.system.MemoryUtil.memFree;

public class Buffer {

    private final float[] vertices;
    private int vaoId;
    private int vboId;

    public Buffer(float[] vertices) {
        this.vertices = vertices;

        init();
    }

    private void init() {
        FloatBuffer verticesBuffer = MemoryUtil.memAllocFloat(vertices.length);
        verticesBuffer.put(vertices).flip();

        vaoId = glGenVertexArrays();
        glBindVertexArray(vaoId);

        vboId = glGenBuffers();
        glBindBuffer(GL_ARRAY_BUFFER, vboId);
        glBufferData(GL_ARRAY_BUFFER, verticesBuffer, GL_STATIC_DRAW);
        memFree(verticesBuffer);

        glVertexAttribPointer(0, 3, GL_FLOAT, false, 0, 0);

        glBindBuffer(GL_ARRAY_BUFFER, 0);
        glBindVertexArray(0);

        if (verticesBuffer != null) {
            MemoryUtil.memFree(verticesBuffer);
        }
    }

    public void destroy() {
        glDisableVertexAttribArray(0);
        glBindBuffer(GL_ARRAY_BUFFER, 0);
        glDeleteBuffers(vboId);
        glBindVertexArray(0);
        glDeleteVertexArrays(vaoId);
    }

    public void render(ShaderProgram program) {
        program.bind();
        glBindVertexArray(vaoId);
        glEnableVertexAttribArray(0);
        glDrawArrays(GL_TRIANGLES, 0, 3);
        glDisableVertexAttribArray(0);
        glBindVertexArray(0);
        program.unbind();
    }
}