moving a player in canvas game while scrolling canvas

I am struggling with player movement in moving canvas game. Moving means left, right or jump using keys. Canvas movement is presented by an offset variables which moves all object on the scene left or right but it also moves the player. So basically the player stands on one spot all the time and canvas is moving left or right... So the player gets off the canvas screen. You can check on this website

Test the game

If you need more information, just leave a comment but I think there should be everything what is necessary for the logic.

Thanks

function Player(x, y) {
     var size = 80;
      GameObject.call(this, x, y, size);
      this.img = document.getElementById("lopta");
      this.rotation = 0;

      this.dx = 0;
      this.dy = 0;

}
var r = this.size * 0.5;

// Dedi vlastnosti z GameObject
Player.prototype = Object.create(GameObject.prototype);

Player.prototype.move = function(dt) {

    var x = this.x;
    var y = this.y;
    this.dx = 0;

    var sirka = canvas.width;
    var vyska = canvas.height;
    var bounce = 0.6;


 // Posun
    if ( keys[37] ) {
        offsetX++;
        this.rotation -= dt;

        //this.dx -= offsetX;
        if(candy != 0)
            candy -= 1;
        else
            gameOver();
    }
    if ( keys[39] ) {
        offsetX--;
        this.rotation += dt;

        //this.dx += offsetX;
        if(candy != 0)
            candy -= 1;
        else
            gameOver();
    }

    if ( keys[38] && Math.abs(this.dy)<2) {
        this.dy -= 70; 
        keys[38] = false;
        if(candy != 0)
            candy -= 3;
        else
            gameOver();
    }

    // Posun
    x = x + this.dx; 
    y = y + this.dy*dt;

    // Test novej pozicie
    var collision = false;

    for (i in enemy) {
      var obj_enemy = enemy[i];

      var r = this.size * 0.5;
      var test_enemy = 

          //kolizia od objektu napravo
          x - r >= obj_enemy.x + obj_enemy.size || 
          //kolizia od objektu nalavo
          x + r <= obj_enemy.x || 
        //kolizia pod objektom
          y - r >= obj_enemy.y + obj_enemy.size || 
        //kolizia nad objektom
          y + r <= obj_enemy.y;

          //podmienka ak lopta spadne na kaktus na pichliace, tak bude game over :)
          //if ( !(y + r <= obj_enemy.y) && !test_enemy)
            //gameOver();

      if (!test_enemy) {
        collision = true;

        break;
      }
    }


    //mince
    //test kolizie pri naraze na mince + zbieranie bodov a mazanie mince pri naraze....
    for (i in coins) {
        var obj_coins = coins[i];

        var test_coins = 

          //kolizia od objektu napravo
                x - r >= obj_coins.x + obj_coins.size || 
          //kolizia od objektu nalavo
                x + r <= obj_coins.x || 
            //kolizia pod objektom
                y - r >= obj_coins.y + obj_coins.size || 
            //kolizia nad objektom
                y + r <= obj_coins.y;

        if (!test_coins) {
          collision = true;
          score += 5;

              coins.splice(i, 1); // vymazanie mince, ktoru hrac ziska - narazi do nej

          break;
        }
      }


    //oxygen

    for (i in outu) {
        var obj_outu = outu[i];

        var test_outu = 

          //kolizia od objektu napravo
                x - r >= obj_outu.x + obj_outu.size || 
          //kolizia od objektu nalavo
                x + r <= obj_outu.x || 
            //kolizia pod objektom
                y - r >= obj_outu.y + obj_outu.size || 
            //kolizia nad objektom
                y + r <= obj_outu.y;

        if (!test_outu) {
          collision = true;
          ox += 10;

              outu.splice(i, 1); // vymazanie mince, ktoru hrac ziska - narazi do nej

          break;
        }
      }

//candy bars

    for (i in energy) {
        var obj_energy = energy[i];

        var test_energy = 

          //kolizia od objektu napravo
                x - r >= obj_energy.x + obj_energy.size || 
          //kolizia od objektu nalavo
                x + r <= obj_energy.x || 
            //kolizia pod objektom
                y - r >= obj_energy.y + obj_energy.size || 
            //kolizia nad objektom
                y + r <= obj_energy.y;

        if (!test_energy) {
          collision = true;
          candy += 10;
              energy.splice(i, 1);  
          break;
        }
      }


    // Posun bez kolizie
    if (!collision) {
        this.x = x; 
        this.y = y;
        // Gravitacia
        this.dy += 9.8 * dt; 
    }else { 
        this.dx = x;
        this.dy *= -bounce;
        if(this.dy * (-bounce)  <   4)
            this.dy = 0;
        if (!collision) 
        { 
            this.x = x; 
            this.y = y; 
            //this.dy *= (-bounce); 
            }
    }

    // podmienky aby lopta nevysla z hracieho pola cize z canvasu
   /* if (this.x + this.size - this.size*0.5> canvas.width) {
        this.x  = canvas.width - this.size + this.size*0.5;

      }
      if (this.x -this.size*0.5 < 0) {
        this.x = this.size*0.5;
      }
      */
      if (this.y+this.size - this.size*0.5 > canvas.height-80) {
        this.y = canvas.height - 80 - this.size + this.size*0.5;

        this.dy *= -bounce;
        if(this.dy * (-bounce)  <   4)
            this.dy = 0;
      }
      //if (this.y - this.size*0.5< 0) { //pomienka pre strop canvasu, ....
       // this.y = this.size*0.5;
      //};
};

Player.prototype.draw = function() {
    ctx.save();
    ctx.translate(this.x + offsetX, this.y + offsetY);
    ctx.rotate(this.rotation);
    ctx.translate(-this.size*0.5, -this.size*0.5);
    ctx.drawImage(this.img, 0, 0, this.size, this.size);
    ctx.restore();
    };