import string
from typing import Any, Iterator

from ..base import BaseSolver


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

        # extract content of each part
        parts = [
            (set(line[: len(line) // 2]), set(line[len(line) // 2 :])) for line in lines
        ]

        # priorities
        priorities = {c: i + 1 for i, c in enumerate(string.ascii_letters)}

        # part 1
        yield sum(priorities[c] for p1, p2 in parts for c in p1.intersection(p2))

        # part 2
        n_per_group = 3
        yield sum(
            priorities[c]
            for i in range(0, len(lines), n_per_group)
            for c in set(lines[i]).intersection(*lines[i + 1 : i + n_per_group])
        )