import datetime

from django.urls.converters import StringConverter
from django.utils.safestring import mark_safe

__all__ = ("PagePathConverter", "WeekConverter", "DateConverter")


class PagePathConverter(StringConverter):
    """Match path for pages, including surrounding slashes."""

    regex = r"/?|([-_a-zA-Z0-9]+/)*?"

    def to_python(self, value):
        if not value or value[0] != "/":
            value = "/" + value
        if len(value) > 1 and value[-1] != "/":
            value = value + "/"
        return value

    def to_url(self, value):
        if value[0] == "/":
            value = value[1:]
        if value[-1] != "/":
            value = value + "/"
        return mark_safe(value)


class WeekConverter:
    """Converter for date as YYYYY/WW."""

    regex = r"[0-9]{4}/[0-9]{2}"

    def to_python(self, value):
        return datetime.datetime.strptime(value + "/1", "%G/%V/%u").date()

    def to_url(self, value):
        return (
            value
            if isinstance(value, str)
            else "{:04d}/{:02d}".format(*value.isocalendar())
        )


class DateConverter:
    """Converter for date as YYYY/MM/DD."""

    regex = r"[0-9]{4}/[0-9]{2}/[0-9]{2}"

    def to_python(self, value):
        value = value.split("/")[:3]
        return datetime.date(int(value[0]), int(value[1]), int(value[2]))

    def to_url(self, value):
        return (
            value
            if isinstance(value, str)
            else "{:04d}/{:02d}/{:02d}".format(
                value.year, value.month, value.day
            )
        )