class Draw {
  // Draws the grid
  function void Grid() {
    var int row;
    var int startBlock;
    let row = 0;
    while(row<3) {
      let startBlock = 32 * (row) * 16;
      do Draw.Border(startBlock);
      do Draw.Border(startBlock + 1);
      do Draw.Border(startBlock + 2);
      let row=row+1;
    }
    return;
  }

  function void Border(int location) {
    var int memAddress;
    let memAddress = 16384+location;
    do Memory.poke(memAddress+0, -1);
    do Memory.poke(memAddress+32, -32767);
    do Memory.poke(memAddress+64, -32767);
    do Memory.poke(memAddress+96, -32767);
    do Memory.poke(memAddress+128, -32767);
    do Memory.poke(memAddress+160, -32767);
    do Memory.poke(memAddress+192, -32767);
    do Memory.poke(memAddress+224, -32767);
    do Memory.poke(memAddress+256, -32767);
    do Memory.poke(memAddress+288, -32767);
    do Memory.poke(memAddress+320, -32767);
    do Memory.poke(memAddress+352, -32767);
    do Memory.poke(memAddress+384, -32767);
    do Memory.poke(memAddress+416, -32767);
    do Memory.poke(memAddress+448, -32767);
    do Memory.poke(memAddress+480, -1);
    return;
  }

  function int Location(int row, int column) {
    return (32 * row * 16) + column;
  }

  function void DrawX(int row, int column) {
    var int l;
    let l = Draw.Location(row, column);
    do Draw.X(l);
    return;
  }
  function void DrawO(int row, int column) {
    var int l;
    let l = Draw.Location(row, column);
    do Draw.O(l);
    return;
  }

  function void X(int location) {
    var int memAddress;
    let memAddress = 16384+location;
    do Memory.poke(memAddress+0, -1);
    do Memory.poke(memAddress+32, -32767);
    do Memory.poke(memAddress+64, -20467);
    do Memory.poke(memAddress+96, -18403);
    do Memory.poke(memAddress+128, -25543);
    do Memory.poke(memAddress+160, -29071);
    do Memory.poke(memAddress+192, -31807);
    do Memory.poke(memAddress+224, -31807);
    do Memory.poke(memAddress+256, -31807);
    do Memory.poke(memAddress+288, -31807);
    do Memory.poke(memAddress+320, -29071);
    do Memory.poke(memAddress+352, -25543);
    do Memory.poke(memAddress+384, -18403);
    do Memory.poke(memAddress+416, -20467);
    do Memory.poke(memAddress+448, -32767);
    do Memory.poke(memAddress+480, -1);
    return;
  }

function void O(int location) {
  var int memAddress;
    let memAddress = 16384+location;
    do Memory.poke(memAddress+0, -1);
    do Memory.poke(memAddress+32, -32767);
    do Memory.poke(memAddress+64, -28687);
    do Memory.poke(memAddress+96, -24583);
    do Memory.poke(memAddress+128, -20467);
    do Memory.poke(memAddress+160, -20467);
    do Memory.poke(memAddress+192, -20467);
    do Memory.poke(memAddress+224, -20467);
    do Memory.poke(memAddress+256, -20467);
    do Memory.poke(memAddress+288, -20467);
    do Memory.poke(memAddress+320, -20467);
    do Memory.poke(memAddress+352, -20467);
    do Memory.poke(memAddress+384, -24583);
    do Memory.poke(memAddress+416, -28687);
    do Memory.poke(memAddress+448, -32767);
    do Memory.poke(memAddress+480, -1);
    return;
  }
}