"""
 craps - work in class 2012
"""

from random import randint

debug = False

def print_debug(message):
    if debug:
        print "   debug: ", message

def d6():
    """ Return number from a 6-sided die
        >>> x = d6()
        >>> x <= 6 and x >= 1
        True
    """
    return randint(1,6)

def two_dice():
    """ Return sum from two 6-sided dice """
    # Note: this is *not* the same as randint(2,12)
    return d6() + d6()

def play_game():
    """ Play a game of craps. Return True if you win. """
    first_roll = two_dice()
    print_debug(" first roll = " + str(first_roll))
    if first_roll in [2, 3, 12]:
        print_debug(" loses on first roll")
        return False
    elif first_roll in [7, 11]:
        print_debug(" wins on first roll")
        return True
    else:
        point = first_roll
        print_debug(" point is " + str(point))
        while True:
            next_roll = two_dice()
            print_debug(" next roll is " + str(next_roll))
            if next_roll == point:
                print_debug(" won with that point")
                return True
            elif next_roll == 7:
                print_debug(" lost")
                return False

def play_n_games(n):
    """ Return number of games won out of n """
    n_wins = 0
    for i in range(n):
        if play_game():
            n_wins = n_wins + 1
    return n_wins

def odds(m_sets, n_games):
    """ Return list of m odds, each set is n games"""
    result = []
    for i in range(m_sets):
        n_wins = play_n_games(n_games)
        result = result + [float(n_wins) / n_games]
        # result.append(float(n_wins) / n_games) # same
    return result

# Python already has this as min()
#
#def minimum(numbers):
#    """ Return smallest of a list of numbers """
#    smallest = numbers[0]
#    for n in numbers:
#        if n < smallest:
#            smallest = n
#    return smallest

def main():
    print "--- Estimated odds of winning at craps ---"
    n_games = input("How many games would you like to simulate? ")
    print "Simulating", n_games, "games ..."
    n_won = play_n_games(n_games)
    print "done."
    print "Number of simulated wins:", n_won
    print "Estimated odds of winning:", float(n_won)/n_games

    print "--- Estimated error ---"
    m_sets = input("How many times would you like to repeat " +
                   "that series of " + str(n_games) + " games? ")
    print "Simulating", m_sets, " sets of", n_games, "games ..."
    list_of_odds = odds(m_sets, n_games)
    lowest = min(list_of_odds)  # aboe started to write minimum()
    highest = max(list_of_odds)
    print "Lowest estimated odds:", lowest
    print "Highest estimated odds:", highest
    print "Error range = (high - low)", (highest - lowest)

if __name__ == "__main__":
    import doctest
    doctest.testmod()
    main()