var menu = true;
const DICE_ARRAY = [0, 4, 6, 8, 10, 12, 20, 100];
const SELECTION_ARRAY = [6, 0, 0, 0, 0, 0, 0, 0]; // default to selecting a single d20

function drawMenu() {
  
  stringArr = new Array ("", "", "", "", "", "", "", "");
  for (i = 0; i < 8; i++) {
    
    if (SELECTION_ARRAY [i] != 0) {
      
      stringArr [i] = "" + DICE_ARRAY [SELECTION_ARRAY [i]];
    }
  }
  
  g.clear();
  g.setFont ("Vector", 40);
  
  g.drawString (("   " + stringArr [0]).slice (-3), 5, 10);
  g.drawString (("   " + stringArr [1]).slice (-3), 5, 50);
  g.drawString (("   " + stringArr [2]).slice (-3), 5, 90);
  g.drawString (("   " + stringArr [3]).slice (-3), 5, 130);
  g.drawString (("   " + stringArr [4]).slice (-3), 96, 10);
  g.drawString (("   " + stringArr [5]).slice (-3), 96, 50);
  g.drawString (("   " + stringArr [6]).slice (-3), 96, 90);
  g.drawString (("   " + stringArr [7]).slice (-3), 96, 130);
}

function touchHandler (button, xy) {
  
  if (! menu) {
    
    menu = true;
    drawMenu();
    return;
  }
  
  if (xy.x <= 87) { // left
    
    if (xy.y <= 43) {
      
      selection = 0;
    } else if (xy.y <= 87) {
      
      selection = 1;
    } else if (xy.y <= 131) {
      
      selection = 2;
    } else {
      
      selection = 3;
    }
  } else { // right
    
    if (xy.y <= 43) {
      
      selection = 4;
    } else if (xy.y <= 87) {
      
      selection = 5;
    } else if (xy.y <= 131) {
      
      selection = 6;
    } else {
      
      selection = 7;
    }
  }
  
  // increment SELECTION_ARRAY [selection]
  if (SELECTION_ARRAY [selection] == 7) {
    
    SELECTION_ARRAY [selection] = 0;
  } else {
    
    SELECTION_ARRAY [selection] += 1;
  }
  
  drawMenu();
}

function rollDice() {
  
  resultsArr = new Uint8Array (8);
  for (i = 0; i < 8; i++) {
    
    if (SELECTION_ARRAY [i] != 0) {
      
      resultsArr [i] = random (DICE_ARRAY [SELECTION_ARRAY [i]]);
    }
  }
  
  g.clear();
  g.setFont ("Vector", 40);
  
  for (i = 0; i < 4; i++) {
    
    if (SELECTION_ARRAY [i] != 0) {
      
      g.drawString (("   " + resultsArr [i]).slice (-3), 5, 10 + 40 * i);
    }
  }
  
  for (i = 4; i < 8; i++) {
    
    if (SELECTION_ARRAY [i] != 0) {
      
      g.drawString (("   " + resultsArr [i]).slice (-3), 96, 10 + 40 * (i - 4));
    }
  }
  
  Bangle.buzz (200, 0.1);
}

function random (max) {
  
  return Math.round (Math.random() * (max - 1) + 1);
}

drawMenu();
Bangle.on ('touch', touchHandler);
Bangle.on ('accel', function (xyz) {
  
  if (xyz.diff >= 0.4) {
    
    menu = false;
    rollDice();
  }
});