"""Custom classes for routing converters."""
import re

from werkzeug.routing import BaseConverter


class CommaSeparatedInt(BaseConverter):
    """Comma separated int pattern matcher."""

    regex = r'\d+(?:,\d+)*,?'

    def to_python(self, value):
        """Override fn to match comma separated int values."""
        if not re.match(r'^\d+(?:,\d+)*,?$', value):
            return []
        return [int(x) for x in value.split(',')]

    def to_url(self, value):
        """Override fn to convert values back to string."""
        return ','.join(str(x) for x in value)


def get_routing_converters():
    """All custom routing converters for this ows.

    Returns:
         dict: a dict of converters {converter_name : class for conversion}
    """
    return {'comma_separated_int': CommaSeparatedInt}