class Ray {
    constructor(xorigin, yorigin, angle, sight) {
        this.origin = createVector(xorigin, yorigin);
        this.direction = p5.Vector.fromAngle(angle); //createVector(xdirection, ydirection);
        this.length = sight;
        this.hit = 0;
        this.intersections = [];
        this.closestIntersection;
    }

    show() {
        if (this.hit >= 1) {
            //stroke(150, 20, 20);s
            stroke(200);
            line(this.origin.x, this.origin.y, this.closestIntersection.x, this.closestIntersection.y);
        } else {
            stroke(200);
            line(this.origin.x, this.origin.y, this.origin.x + this.direction.x * this.length, this.origin.y + this.direction.y * this.length);
            //line(this.origin.x, this.origin.y, mouseX, mouseY);
        }/*
        if (this.hit >= 1 && this.closestIntersection) {

            fill(51);
            noStroke();
            ellipse(this.closestIntersection.x, this.closestIntersection.y, 5, 5);
        }*/

    }

    cast(wall) {
        if (wall) {
            const x1 = this.origin.x;
            const y1 = this.origin.y;
            const x2 = this.origin.x + this.direction.x * this.length;
            const y2 = this.origin.y + this.direction.y * this.length;
            //const x2 = mouseX;
            //const y2 = mouseY;

            const x3 = wall.a.x;
            const y3 = wall.a.y;
            const x4 = wall.b.x;
            const y4 = wall.b.y;

            const den = ((x1 - x2) * (y3 - y4) - (y1 - y2) * (x3 - x4));
            if (den == 0) {
                return;
            }

            const t = ((x1 - x3) * (y3 - y4) - (y1 - y3) * (x3 - x4)) / den;
            const u = -((x1 - x2) * (y1 - y3) - (y1 - y2) * (x1 - x3)) / den;

            if (t >= 0 && t <= 1 && u >= 0 && u <= 1) {
                this.hit++;
                this.intersections.push(createVector(x1 + t * (x2 - x1), y1 + t * (y2 - y1)));
            }
            this.distance = Infinity;

            if (this.intersections && this.intersections.length) {
                if (this.hit) {
                    for (let i = 0; i < this.intersections.length; i++) {
                        if (p5.Vector.dist(createVector(x1, y1), this.intersections[i]) < this.distance) {
                            this.closestIntersection = this.intersections[i];
                            this.distance = p5.Vector.dist(createVector(x1, y1), this.intersections[i])
                        }
                    }
                }
            }
        } else {

            if (this.hit >= 1)
                return this.distance;
            else
                return null;
        }
    }


}

function distanceFromVectors(v1, v2) {
    //var distance = abs(v1.x - v2.x) + abs(v1.y - v2.y)
    var distance = sqrt(sq(v1.x - v2.x) + sq(v1.y - v2.y));
    return distance;
}