import { minus, plus } from "./math";
import { vec2 } from "./vec2";

export class Rect
{
    min: vec2;
    max: vec2;
    constructor(min: vec2, size: vec2)
    {
        this.min = min;
        this.max = plus(min, size);
    }

    get xMin() { return this.min.x }
    get yMin() { return this.min.y }
    get xMax() { return this.max.x }
    get yMax() { return this.max.y }
    get width() { return this.max.x - this.min.x }
    get height() { return this.max.y - this.min.y }
    get size() { return minus(this.max, this.min) }
    get center() { return plus(this.min, this.max).mul(vec2(.5)) }

    shrink(thickness: number)
    {
        let min = plus(this.min, vec2(thickness));
        let max = minus(this.max, vec2(thickness));
        if (min.x > max.x)
            min.x = max.x = (min.x + max.x) / 2;
        if (min.y > max.y)
            min.y = max.y = (min.y + max.y) / 2;
        return new Rect(min, max.minus(min));
    }

    expand(thickness: number)
    {
        return new Rect(minus(this.min, vec2(thickness)), plus(this.size, vec2(2 * thickness)));
    }

    static box01()
    {
        return new Rect(vec2.zero(), vec2.one());
    }
}