alphabet_keyboard.py

class Cursor(object):
  def __init__(self):
    self.x, self.y = 0, 0
    self.dirs = {
      'd': (0, 1),
      'u': (0, -1),
      'r': (1, 0),
      'l': (-1, 0)
    }

  def consume_input(self, c):
    if c in self.dirs:
      x, y = self.dirs[c]
      self.x += x
      self.y += y

  def get_at(self, selection):
    if self.y >= len(selection) or self.x >= len(selection[0]):
      return None
    return selection[self.y][self.x]


def get_alphabet():
  alpha = []
  tmp = []
  for i in xrange(26):
    if i % 5 == 0 and i > 0:
      alpha.append(tmp)
      tmp = []
    tmp.append(chr(ord('a') + i))
  alpha.append(tmp)
  return alpha


def execute_moves(moves):
  s = ''
  alpha = get_alphabet()
  c = Cursor()
  for move in moves:
    for m in move:
      if m == '!':
        s += c.get_at(alpha)
        break
      c.consume_input(m)
  return s


def get_location(c, w):
  return (ord(c) - ord('a')) % w, (ord(c) - ord('a')) / w


def get_moves_for_word(word):
  d = []
  alpha = get_alphabet()
  last = (0, 0)

  for c in word:
    x, y = get_location(c, 5)
    dX, dY = x - last[0], y - last[1]

    if dX == 0 and dY == 0:
      d.append(['!'])
      continue

    d.append((['d' if dY > 0 else 'u'] * abs(dY)) + (['r' if dX > 0 else 'l'] * abs(dX)) + ['!'])
    last = (x, y)

  return d


def main():
  tests = ['google', 'kyle', 'hello', 'world', 'helloworld', 'programming']
  for test in tests:
    print test, test == execute_moves(get_moves_for_word(test))

if __name__ == '__main__':
  main()