class BBox {
	static fromLTWH(l, t, w, h){
		return BBox.fromLTRB(l, t, l + w, t + h)
	}

	static fromLTRB(l, t, r, b){		
		return Object.assign(new BBox(), {l: Math.min(l, r), t: Math.min(t, b), r: Math.max(l, r), b: Math.max(t, b)})
	}

	static from_array(arr_xy){
		const bbox = BBox.fromLTWH(arr_xy[0].x, arr_xy[0].y, 0, 0)
		return bbox.append_many(arr_xy)
	}

	w(){
		return this.r - this.l
	}

	h(){
		return this.b - this.t
	}

	toLTWH(){
		const {l, t, r, b} = this
		return {l, t, w: r - l, h: b - t }
	} 

	toLTRB(){
		const {l, t, r, b} = this
		return {l, t, r, b}
	}

	toLTRBarr(){
		const {l, t, r, b} = this
		return [l, t, r, b]
	}

	append(x, y){
		this.l = Math.min(this.l, x)
		this.t = Math.min(this.t, y)
		this.r = Math.max(this.r, x)
		this.b = Math.max(this.b, y)
		return this
	}

	append_many(arr_xy){
		arr_xy.forEach(e => this.append(e.x, e.y))
		return this
	}

    scale(k){		
        this.r = this.l + (this.r - this.l) * k
        this.b = this.t + (this.b - this.t) * k
        return this
    }

    move(dx, dy){
		this.l += dx
        this.t += dy
        this.r += dx
        this.b += dy
        return this
    }

    moveto(x, y){
        let dx = x - this.l
        let dy = y - this.t
        return this.move(dx, dy)
    }

	clone(){
		return BBox.fromLTRB(this.l, this.t, this.r, this.b)
	}
}

module.exports = BBox
module.exports.default = BBox