#!/usr/bin/python

import random
from enum import Enum

import dictionary


class LetterResult(Enum):
    """Is an individual letter in a word in the result?"""

    CORRECT = "C"
    MOVE = "M"
    INCORRECT = "I"
    UNKNOWN = "U"


class InvalidWord(Exception):
    """Thrown when an input word is not a valid Wordle."""

    pass


def select_word(words=dictionary.words()):
    return random.choice(list(words))


def grade_word(target, guess, words=dictionary.words()):
    # We don't check word length, since all valid words are 5 letters.
    if guess not in words:
        raise InvalidWord(f"{guess} is not a valid Wordle.")

    result = [LetterResult.UNKNOWN] * dictionary.WORDLE_LENGTH

    # We copy target, and remove letters if we find them. This handles duplicate letters correctly.
    # For example, if the target is "pulls" and we guess "apple", only the first "p" should be a
    # MOVE. The second should be INCORRECT.
    remaining = list(target)

    # Find all correct results first.
    for i in range(dictionary.WORDLE_LENGTH):
        if target[i] == guess[i]:
            result[i] = LetterResult.CORRECT
            remaining.remove(guess[i])

    for i in range(dictionary.WORDLE_LENGTH):
        if result[i] == LetterResult.UNKNOWN:
            if guess[i] in remaining:
                # Letter is in the wrong place.
                result[i] = LetterResult.MOVE
                remaining.remove(guess[i])
            else:
                # Letter is not in target.
                result[i] = LetterResult.INCORRECT

    return result


def display_result(result, text):
    opening = {
        LetterResult.CORRECT: "\033[92m",
        LetterResult.MOVE: "\033[33m",
        LetterResult.INCORRECT: "\033[36m",
        LetterResult.UNKNOWN: "",
    }
    closing = "\033[0m"

    return f"{opening[result]}{text}{closing}"


def success_result(result):
    for r in result:
        if r != LetterResult.CORRECT:
            return False

    return True