Mover.jack

class Mover {
    field Grid grid;
    field int pos;
    field bool draw, listen, done;
    
    constructor Mover new(Grid g) {
        let grid = g;
        let pos = grid.center();
        do grid.setPos(pos);
        let draw = false;
        let listen = true;
        return this;
    }

    //in draw mode, will leave trail of active grid squares
    //out of draw mode, will erase trails
    method void mode() {
        let draw = ~draw;
        return;
    }

    method void moveLeft() {
        if (~draw) {
            do grid.unSetPos(pos);
            do grid.drawPos(pos);
        }
        let pos = grid.left(pos);
        do grid.setPos(pos);
        return;
    }
    method void moveRight() {
        if (~draw) {
            do grid.unSetPos(pos);
            do grid.drawPos(pos);
        }
        let pos = grid.right(pos);
        do grid.setPos(pos);
        return;
    }
    method void moveUp() {
        if (~draw) {
            do grid.unSetPos(pos);
            do grid.drawPos(pos);
        }
        let pos = grid.up(pos);
        do grid.setPos(pos);
        return;
    }
    method void moveDown() {
        if (~draw) {
            do grid.unSetPos(pos);
            do grid.drawPos(pos);
        }
        let pos = grid.down(pos);
        do grid.setPos(pos);
        return;
    }

    method void step() {
        var char key;
        let key = Keyboard.keyPressed();

        if (key = 32) { //spacebar to toggle draw mode
            let draw = true;
            // do Sys.wait(500); //so we don't double count spacebar hits
        }
        if (key = 130) {
            do moveLeft();
            let draw = false;               
        }
        if (key = 131) {
            do moveUp();
            let draw = false;
        }
        if (key = 132) {
            do moveRight();
            let draw = false;
        }
        if (key = 133) {
            do moveDown();
            let draw = false;
        }
        if (key = 140) {
            let done = true;
        }
        do grid.drawPos(pos);
        return;
    }

    method Grid state() {
        return grid;
    }

    method bool done() {
        return done;
    }
    method void dispose() {
        do grid.dispose();
        do Memory.deAlloc(this);
        return;
    }
}