import re

# EXAMPLE = "xmul(2,4)%&mul[3,7]!@^do_not_mul(5,5)+mul(32,64]then(mul(11,8)mul(8,5))"
EXAMPLE = "xmul(2,4)&mul[3,7]!^don't()_mul(5,5)+mul(32,64](mul(11,8)undo()?mul(8,5))"

INST_RE = re.compile(r"(mul\(\d+,\d+\)|do\(\)|don't\(\))")


class ParseInstructions:
    """Parse instructions and get results"""

    def __init__(self, input: str):
        self.input = input
        self.instructions = INST_RE.findall(self.input)

    def __str__(self) -> str:
        return f"Part 1 = {self._part1}, Part 2 = {self._part2}"

    def _mul(self, inst: str) -> int:
        vars = re.findall(r"\d+", inst)
        return int(vars[0]) * int(vars[1])

    @property
    def _part1(self):
        outp = 0
        for inst in self.instructions:
            if inst.startswith("mul"):
                outp += self._mul(inst)
        return outp

    @property
    def _part2(self):
        outp = 0
        enabled = True
        for inst in self.instructions:
            if inst.startswith("don't"):
                enabled = False
            elif inst.startswith("do"):
                enabled = True
            elif inst.startswith("mul") and enabled:
                outp += self._mul(inst)
        return outp


if __name__ == "__main__":
    example = ParseInstructions(EXAMPLE)
    print(example)
    assert example._part1 == 161
    assert example._part2 == 48
    with open("input.txt", "r") as f:
        puzzle = ParseInstructions(f.read())
        print(puzzle)