package renderSuite;

import renderSuite.Vec3;
import renderSuite.Ray;

import java.awt.image.BufferedImage;
import javax.imageio.ImageIO;

import java.io.File;

public class Camera {
    private Vec3 p, f;
    private double fov;
    private int sizeX, sizeY;

    public Camera(Vec3 position, Vec3 facing, double fov, int sizeX, int sizeY) {
        this.p = position;
        this.f = facing;
        this.fov = fov;
        this.sizeX = sizeX;
        this.sizeY = sizeY;
    }

    public void main() {

    }

    public void renderImageTo(String filename, Surface[] surfs) {
        BufferedImage bi = new BufferedImage(this.sizeX, this.sizeY, BufferedImage.TYPE_INT_RGB);

        for (int x = 0; x < this.sizeX; x++) {
            for (int y = 0; y < this.sizeY; y++) {
                Vec3 result = probe(x, y);
                int color = ( (int)result.x ) << 16 | ( (int)result.y ) << 8 | ( (int)result.z );
                bi.setRGB(x, y, color);
            }
        }

        File f = new File(filename + ".png");
        ImageIO.write(bi, "PNG", f);
    }

    public Vec3 probe(int x, int y) {
        Vec3 result = new Vec3(0, 0, 0);
        
        // creating ray to use as a probing object
        Ray ray = new Ray(this.p.copy(), this.f.copy().get_norm());

        // adjust ray facing
        double offsetX = ((x/this.sizeX) - 0.5) * 2;
        ray.rotate('y', offsetX * this.fov);

        double offsetY = ((y/this.sizeY) - 0.5) * 2;
        ray.rotate('x', offsetY * this.fov);

        // check collisions with every object on scene
        for (int i = 0; i < surfs.length; i++) {
            if (surfs[i].intersect(ray)) {
                return surfs[i].color;
            }
        }
        
        // if no collision detected, return black pixel
        return new Vec3(0, 0, 0);
    }
}