import re

from django.core.exceptions import ValidationError


class PasswordComplexityValidator:
    lower_pattern = re.compile(r"[a-z]")
    upper_pattern = re.compile(r"[A-Z]")
    digit_pattern = re.compile(r"\d")
    symbol_pattern = re.compile(r"[^A-Za-z0-9]")

    message = (
        "Password must be at least 8 characters and include at least one lowercase "
        "letter, one uppercase letter, one digit, and one symbol."
    )
    code = "password_no_complexity"

    def validate(self, password, user=None):
        if (
            len(password) < 8
            or not self.lower_pattern.search(password)
            or not self.upper_pattern.search(password)
            or not self.digit_pattern.search(password)
            or not self.symbol_pattern.search(password)
        ):
            raise ValidationError(self.message, code=self.code)

    def get_help_text(self):
        return self.message