import random

"""
db is a defaultdict(list) like this: {(word1, word2): [possible words]}
"""


CHAIN_LENGTH = 2
STOP_WORD = '\x02'
MAX_WORDS = 50


def generate_message(db):
    key = random.choice(list(db.keys()))
    gen_words = []
    for i in range(MAX_WORDS):
        gen_words.append(key[0])
        next_word = random.choice(db[key])
        if not next_word or next_word is STOP_WORD:
            break
        key = key[1:] + (next_word,)

    return ' '.join(gen_words)