import itertools
from collections import defaultdict
from typing import Any, Iterator, Literal, cast

import parse  # type: ignore

from ..base import BaseSolver


def max_change_in_happiness(happiness: dict[str, dict[str, int]]) -> int:
    guests = list(happiness)
    return max(
        sum(
            happiness[o][d] + happiness[d][o]
            for o, d in zip((guests[0],) + order, order + (guests[0],))
        )
        for order in map(tuple, itertools.permutations(guests[1:]))
    )


class Solver(BaseSolver):
    def solve(self, input: str) -> Iterator[Any]:
        lines = input.splitlines()

        happiness: dict[str, dict[str, int]] = defaultdict(dict)
        for line in lines:
            u1, gain_or_loose, hap, u2 = cast(
                tuple[str, Literal["gain", "lose"], int, str],
                parse.parse(  # type: ignore
                    "{} would {} {:d} happiness units by sitting next to {}.", line
                ),
            )
            happiness[u1][u2] = hap if gain_or_loose == "gain" else -hap

        yield max_change_in_happiness(happiness)
        for guest in list(happiness):
            happiness["me"][guest] = 0
            happiness[guest]["me"] = 0

        yield max_change_in_happiness(happiness)