"""
Custom middleware for host-based URL routing.

Routes requests based on hostname:
- *.rfiles.online (subdomains) → shared space portal
- rfiles.online / www.rfiles.online → main upload portal
"""

import re
from django.urls import set_urlconf
import logging

logger = logging.getLogger(__name__)


class HostBasedURLConfMiddleware:
    """
    Middleware that switches URL configuration based on the request host.

    - rfiles.online / www.rfiles.online -> config.urls (main portal)
    - *.rfiles.online -> config.urls_shared_space (shared space portal)
    """

    RFILES_SUBDOMAIN_PATTERN = re.compile(r'^([a-z0-9-]+)\.rfiles\.online$')

    def __init__(self, get_response):
        self.get_response = get_response

    def __call__(self, request):
        host = request.get_host().split(':')[0].lower()

        # Reset any previous shared space context
        request.shared_space_slug = None

        # Check for rfiles.online subdomain pattern
        match = self.RFILES_SUBDOMAIN_PATTERN.match(host)
        if match:
            subdomain = match.group(1)
            if subdomain not in ('www', 'direct'):
                request.shared_space_slug = subdomain
                request.urlconf = 'config.urls_shared_space'
                set_urlconf('config.urls_shared_space')
                logger.info(f"Using shared space URLs for host: {host}, slug: {subdomain}")
                response = self.get_response(request)
                set_urlconf(None)
                return response

        # All other hosts (rfiles.online, www.rfiles.online, localhost) → main portal
        request.urlconf = 'config.urls'
        set_urlconf('config.urls')

        response = self.get_response(request)
        set_urlconf(None)
        return response