import re
from typing import Optional, Pattern


class TokenEscaper:
    """
    Escape punctuation within an input string.
    """
    # Characters that RediSearch requires us to escape during queries.
    # Source: https://oss.redis.com/redisearch/Escaping/#the_rules_of_text_field_tokenization
    DEFAULT_ESCAPED_CHARS = r"[,.<>{}\[\]\\\"\':;!@#$%^&*()\-+=~\ ]"

    def __init__(self, escape_chars_re: Optional[Pattern] = None):
        if escape_chars_re:
            self.escaped_chars_re = escape_chars_re
        else:
            self.escaped_chars_re = re.compile(self.DEFAULT_ESCAPED_CHARS)

    def escape(self, string: str) -> str:
        def escape_symbol(match):
            value = match.group(0)
            return f"\\{value}"

        return self.escaped_chars_re.sub(escape_symbol, string)