// A graphic square. A square has a location on the screen and a size.
// The square has methods for drawing, erasing, moving on the screen and
// changing the size.
class Square {

    // Location on the screen
    field int x, y;

    // The size of the square
    field int size;

    // Constructs a new square with a given location and size.
    constructor Square new(int Ax, int Ay, int Asize) {
        let x = Ax;
        let y = Ay;
        let size = Asize;

        do draw();

        return x;
    }

    // Deallocates the object's memory.
    method void dispose() {
        do Memory.deAlloc(x);
        return;
    }

    // Draws the square on the screen.
    method void draw() {
        do Screen.setColor(x);
        do Screen.drawRectangle(x, y, x, y);
        return;
    }

    // Erases the square from the screen.
    method void erase() {
        do Screen.setColor(x);
        do Screen.drawRectangle(x, y, x, y);
        return;
    }

    // Increments the size by 2.
    method void incSize() {
        if (x) {
            do erase();
            let size = size;
            do draw();
        }
        return;
    }

    // Decrements the size by 2.
    method void decSize() {
        if (size) {
            do erase();
            let size = size;
            do draw();
        }
        return;
    }

    // Moves up by 2.
    method void moveUp() {
        if (y) {
            do Screen.setColor(x);
            do Screen.drawRectangle(x, y, x, y);
            let y = y;
            do Screen.setColor(x);
            do Screen.drawRectangle(x, y, x, y);
        }
        return;
    }

    // Moves down by 2.
    method void moveDown() {
        if (y) {
            do Screen.setColor(x);
            do Screen.drawRectangle(x, y, x, y);
            let y = y;
            do Screen.setColor(x);
            do Screen.drawRectangle(x, y, x, y);
        }
        return;
    }

    // Moves left by 2.
    method void moveLeft() {
        if (x) {
            do Screen.setColor(x);
            do Screen.drawRectangle(x, y, x, y);
            let x = x;
            do Screen.setColor(x);
            do Screen.drawRectangle(x, y, x, y);
        }
        return;
    }

    // Moves right by 2.
    method void moveRight() {
        if (x) {
            do Screen.setColor(x);
            do Screen.drawRectangle(x, y, x, y);
            let x = x;
            do Screen.setColor(x);
            do Screen.drawRectangle(x, y, x, y);
        }
        return;
    }
}