# Solutions
# pig_latin.py

# use pig_latin function we wrote in homework 2

VOWELS = ['a', 'e', 'i', 'o', 'u']
DOUBLES = ['th', 'st', 'qu', 'pl', 'tr']
PUNCTUATION = ['.', '?', '!', ',', ':', ';']

def pig_latin(word):
    # word is a string to convert to pig-latin
    if not isinstance(word, str):
        return 'Word must be a string'
    
    # determine if there is punctuation involved    
    punctuation = False
    if word[-1] in PUNCTUATION:
        punctuation = True
        punc_char = word[-1]
        word = word[:-1]
     
    # follow all rules to convert to pig latin    
    if len(word) >= 2 and word[:2] in DOUBLES:
        pig_word = word[2:] + word[:2] + 'ay'
    elif word[0] in VOWELS:
        pig_word = word + 'hay'
    else:
        pig_word = word[1:] + word[0] + 'ay'
    
    # finally, if there was punctuation, add it at the end!
    if punctuation:
        pig_word += punc_char
        
    return pig_word
    
def pig_latin_sentence():
    # asks user for sentence of only words and spaces to convert to pig-latin
    while True:
        sentence = raw_input('Please enter a sentence with only words and spaces: ')

        if sentence == 'QUIT':
            break
        # prepare sentence for translation
        lower = sentence.lower()
        wordlist = lower.split()
        converted = ''
        for word in wordlist:
            converted += (pig_latin(word)) + ' '
        # remove last space
        converted = converted[:-1]
        print converted

pig_latin_sentence()