package william.starsight.graphics.texture;

import org.lwjgl.BufferUtils;
import org.lwjgl.system.MemoryUtil;

import java.awt.image.BufferedImage;
import java.nio.ByteBuffer;

import static org.lwjgl.opengl.GL43.*;

public class BufferedImageBasedTexture extends Texture {
    private ByteBuffer imgData;
    private final int width;
    private final int height;

    public BufferedImageBasedTexture(BufferedImage img, boolean usesAlpha) { // TODO Fix the black pixel problem
        int width = img.getWidth();
        int height = img.getHeight();
        imgData = BufferUtils.createByteBuffer(width * height * 4); // For the RGBA format :D
        // imgData = MemoryUtil.memAlloc(width * height * 4); tried this

        this.width = width;
        this.height = height;


        for (int y = 0; y < width; y++) {
            for (int x = 0; x < height; x++) {
                int pixel = img.getRGB(x, y);
                byte alpha = (byte) ((pixel >> 24) & 0xFF);
                byte red = (byte) ((pixel >> 16) & 0xFF);
                byte green = (byte) ((pixel >> 8) & 0xFF);
                byte blue = (byte) (pixel & 0xFF);
                imgData.put(red);
                imgData.put(green);
                imgData.put(blue);
                imgData.put(usesAlpha ? alpha : (byte) 255);
            }
        }
        imgData.flip();
    }

    @Override
    public void initialize() {
        textureId = glGenTextures();
        glBindTexture(GL_TEXTURE_2D, textureId);

        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT);
        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT);
        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR_MIPMAP_LINEAR);
        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);

        glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA8, width, height, 0, GL_RGBA8, GL_UNSIGNED_BYTE, imgData);
        glBindTexture(GL_TEXTURE_2D, 0);
    }

    @Override
    protected void textureSubclassCleanup() {
        imgData.clear();
//      MemoryUtil.memFree(imgData); // Clear it entirely :D
    }
}

/*
Shader used:

#version 430

in vec2 fragUV;
in vec3 fragNormals; // unused

uniform sampler2D texSampler;

out vec4 outColor;

void main() {
    outColor = texture(texSampler, fragUV);
}

*/