'''
Name: Catie Welsh
Date: 3/20/2015
Class: CS142
Pledge: I have neither given nor received unauthorized aid on this program. 
Description: This program lets you play one round of the game
  Rock-Paper-Scissors-Lizard-Spock.
Input: Player names and their gestures/throws.
Output: Status of the game and who wins.
'''

# Holds the names of the gestures you can throw.
# OK to make this a global constant because this never changes.
gestures = ["Rock", "Paper", "Scissors", "Lizard", "Spock"]

# This matrix (aka 2D list or 2D array) stores the winner and loser for
# each pair of gestures.  Gestures are indexed by the "gestures" array above.
# If gesture x beats gesture y, then winloss[x][y] = 1 and winloss[y][x] = 0.
# If gesture x ties gesture y, then winloss[x][y] = 2.
# For example, winloss[0][1] = 0, which means Rock (gesture 0) loses to
# Paper (gesture 1).  Conversely, winloss[1][0] = 1.
winloss = [[2, 0, 1, 1, 0],
           [1, 2, 0, 0, 1],
           [0, 1, 2, 1, 0],
           [0, 1, 0, 2, 1],
           [1, 0, 1, 0, 2]]

def main():
    print_greeting()

    name1 = input("Please enter Player 1's name: ")
    name2 = input("Please enter Player 2's name: ")

    # throw1 and throw2 hold the numbers of the gestures
    throw1 = input_throw(name1, name2)
    throw2 = input_throw(name2, name1)

    # winner is 1 if player 1 wins, 0 if player 1 loses, 2 for a tie.
    winner = calc_winner(throw1, throw2)

    while winner == 2:
        print("It's a tie; both players will throw again.")
        throw1 = input_throw(name1, name2)
        throw2 = input_throw(name2, name1)
        winner = calc_winner(throw1, throw2)

    if winner == 1:
        print(gestures[throw1], "defeats", gestures[throw2] + ".")
        print(name1, "defeats", name2 + ".")
    else:
        print(gestures[throw2], "defeats", gestures[throw1] + ".")
        print(name2, "defeats", name1 + ".")

# Prints a greeting.
# Parameters: None
# Returns: None
def print_greeting():
    print("Welcome to Rock-Paper-Scissors-Lizard-Spock!")

# Prints a list of all gestures.
# Parameters: None
# Returns: None
def print_gestures():
    print("Choices are:")
    print("(0) Rock, (1) Paper, (2) Scissors, (3) Lizard, (4) Spock")

# Lets the user type in a number between 0 and 5.
# Parameters: None
# Returns: the number typed.
def input_throw(thrower, opponent):
    print("It is", thrower + "'s turn.")
    print_gestures()
    print("No peeking,", opponent + ".")
    the_throw = int(input(thrower + ", what is your throw? "))

    while the_throw < 0 or the_throw >= len(gestures):
        print("Invalid choice; try again.")
        the_throw = int(input(thrower + ", what is your throw? "))

    print(thrower, "throws", gestures[the_throw] + ".")

    return the_throw

# Calculates the winner of one round of the game.
# Parameters: None
# Returns: the winner as an integer: 1 if player 1 wins,
#  0 if player 1 loses, 2 if they tie.
def calc_winner(throw1, throw2):
    return winloss[throw1][throw2]

main()