#!/usr/bin/env python3

import itertools
import logging
import string
import sys
from typing import Set

from pyutils import bootstrap, config
from pyutils.unscrambler import Unscrambler

cfg = config.add_commandline_args(
    f'Scrabble (aka Wordscapes)! ({__file__})',
    'Find all words in a query letter set (proper and subset based)',
)
cfg.add_argument(
    '--min_length',
    help='Minimum length permissable in results',
    metavar='N',
    type=int,
    default=1,
)
cfg.add_argument(
    '--show_scrabble_score',
    help='Should we compute and display Scrabble game scores?',
    action='store_true',
)
cfg.add_argument(
    '--extra_letters',
    help='Set of letters available on the board (not in hand).  e.g. --extra_letters s t r',
    nargs='*',
)
logger = logging.getLogger(__name__)


scrabble_score_by_letter = {
    'a': 1,
    'e': 1,
    'i': 1,
    'l': 1,
    'n': 1,
    'o': 1,
    'r': 1,
    's': 1,
    't': 1,
    'u': 1,
    'd': 2,
    'g': 2,
    'b': 3,
    'c': 3,
    'm': 3,
    'p': 3,
    'f': 4,
    'h': 4,
    'v': 4,
    'w': 4,
    'y': 4,
    'k': 5,
    'j': 8,
    'x': 8,
    'q': 10,
    'z': 10,
}


def fill_in_blanks(letters: str, skip: Set[str]) -> str:
    if '_' not in letters:
        logger.debug('Filled in blanks: %s', letters)
        yield letters
        return

    for replacement in string.ascii_lowercase:
        filled_in = letters.replace('_', replacement, 1)
        if filled_in not in skip:
            logger.debug(
                'Orig: %s, replacement is %s, new: %s', letters, replacement, filled_in
            )
            skip.add(filled_in)
            yield from fill_in_blanks(filled_in, skip)


def lookup_letter_set(
    letters: str,
    unscrambler: Unscrambler,
    seen_sigs: Set[int],
    seen_words: Set[str],
) -> None:
    sig = unscrambler.compute_word_sig(letters)
    if sig not in seen_sigs:
        logger.debug('%s => %s', letters, sig)
        for (words, exact) in unscrambler.lookup_by_sig(sig).items():
            if exact:
                for word in words.split(','):
                    if len(word) >= config.config['min_length']:
                        seen_words.add(word)
                    else:
                        logger.debug('Skipping %s because it\'s too short.', word)
        seen_sigs.add(sig)


@bootstrap.initialize
def main() -> None:
    if len(sys.argv) < 2:
        print("Missing required query.", file=sys.stderr)
        sys.exit(-1)

    seen_sigs: Set[int] = set()
    seen_words: Set[str] = set()
    seen_fill_ins: Set[str] = set()
    u: Unscrambler = Unscrambler()

    query = sys.argv[1].lower()
    orig_letters = set([x for x in query if x != '_'])
    logger.debug('Initial query: %s (%s)', query, orig_letters)

    if config.config['extra_letters']:
        for extra in config.config['extra_letters']:
            extra = extra.lower()
            query = query + extra
            logger.debug('Building with extra letter: %s; query is %s', extra, query)
            for q in fill_in_blanks(query, seen_fill_ins):
                logger.debug('...blanks filled in: %s', q)
                for x in range(config.config['min_length'], len(q) + 1):
                    for tup in itertools.combinations(q, x):
                        letters = ''.join(tup)
                        logger.debug('...considering subset: %s', letters)
                        lookup_letter_set(letters, u, seen_sigs, seen_words)
            query = query[:-1]
            logger.debug('Removing extra letter; query is %s', query)
    else:
        for q in fill_in_blanks(query, seen_fill_ins):
            logger.debug('...blanks filled in: %s', q)
            for x in range(config.config['min_length'], len(q) + 1):
                for tup in itertools.combinations(q, x):
                    letters = ''.join(tup)
                    logger.debug('...considering subset: %s', letters)
                    lookup_letter_set(letters, u, seen_sigs, seen_words)

    output = {}
    for word in sorted(seen_words):
        if config.config['show_scrabble_score']:
            score = 0
            copy = orig_letters.copy()
            for letter in word:
                if letter in copy:
                    copy.remove(letter)
                    score += scrabble_score_by_letter.get(letter, 0)
            if len(word) >= 7:
                score += 50
            output[word] = score
        else:
            output[word] = len(word)

    for word, n in sorted(output.items(), key=lambda x: x[1]):
        if config.config['show_scrabble_score']:
            print(f'{word} => {n}')
        else:
            print(word)


if __name__ == "__main__":
    main()