"""
Main URL Configuration for the Django Backend Starter Template.
"""
import os
import re
import mimetypes
from django.contrib import admin
from django.urls import path, include, re_path
from django.conf import settings
from django.conf.urls.i18n import i18n_patterns
from django.http import StreamingHttpResponse, HttpResponse, Http404
from django.views.static import serve as django_static_serve

from django.views.generic import RedirectView
from drf_spectacular.views import (
    SpectacularAPIView,
    SpectacularRedocView,
    SpectacularSwaggerView,
)
from rest_framework_simplejwt.views import (
    TokenObtainPairView,
    TokenRefreshView,
    TokenVerifyView,
)
from rest_framework import permissions

from utils.admin import project_admin_site, HomeView

# API v1 Patterns
api_v1_patterns = [
    # Auth & Identity endpoints
    path('auth/', include('apps.account.urls_auth')),
    
    # Institution Profiles
    path('profiles/', include('apps.profiles.urls')),
    
    # Smart Geo-Atlas & Spatial Map
    path('map/', include('apps.geo_map.urls')),
    
    # International Content Management System (CMS)
    path('cms/', include('apps.cms.urls')),
    
    # Collaborative Projects & Kanban
    path('projects/', include('apps.projects.urls')),
    
    # Real-Time Messaging & Chat
    path('chat/', include('apps.chat.urls')),
    
    # Events & Programs Calendar
    path('events/', include('apps.events.urls')),
    
    # Inter-Center Video Meetings & Scheduling
    path('meetings/', include('apps.meetings.urls')),
    
    path('', include('apps.api.urls')),
    path('account/', include('apps.account.urls')),
    path('settings/', include('dynamic_preferences.urls')),
]

urlpatterns = [
    # Language prefix routing for Admin
    path("i18n/", include("django.conf.urls.i18n")),
    
    # REST API Endpoints
    path("api/v1/", include(api_v1_patterns)),

    # OpenAPI 3.0 & Interactive Documentation (matching swagger-api-guide.md)
    path("api/schema/", SpectacularAPIView.as_view(), name="schema"),
    path("api/schema/swagger-ui/", SpectacularSwaggerView.as_view(url_name="schema"), name="swagger-ui"),
    path("api/schema/redoc/", SpectacularRedocView.as_view(url_name="schema"), name="redoc"),

    # Backward compatibility redirect
    path("swagger/", RedirectView.as_view(url="/api/schema/swagger-ui/", permanent=False)),
]

# Admin URLs wrapped in i18n
urlpatterns += i18n_patterns(
    path("admin/", project_admin_site.urls),
    prefix_default_language=True,
)

# Static & Media streaming for development mode
if settings.DEBUG:
    def ranged_static_serve(request, path, document_root=None, **kwargs):
        fullpath = os.path.join(document_root, path)
        if not os.path.exists(fullpath) or os.path.isdir(fullpath):
            raise Http404("File not found")
            
        range_header = request.META.get('HTTP_RANGE', '').strip()
        if not range_header:
            return django_static_serve(request, path, document_root=document_root, **kwargs)
            
        size = os.path.getsize(fullpath)
        content_type, encoding = mimetypes.guess_type(fullpath)
        content_type = content_type or 'application/octet-stream'
        
        match = re.match(r'bytes=(\d+)-(\d*)', range_header)
        if not match:
            return HttpResponse("Invalid Range Header", status=400)
            
        first_byte, last_byte = match.groups()
        first_byte = int(first_byte) if first_byte else 0
        last_byte = int(last_byte) if last_byte else size - 1
        
        if first_byte >= size:
            return HttpResponse("Requested Range Not Satisfiable", status=416)
            
        if last_byte >= size:
            last_byte = size - 1
            
        length = last_byte - first_byte + 1
        
        def file_iterator(file_path, offset, bytes_to_read, chunk_size=8192):
            with open(file_path, 'rb') as f:
                f.seek(offset)
                remaining = bytes_to_read
                while remaining > 0:
                    to_read = min(chunk_size, remaining)
                    data = f.read(to_read)
                    if not data:
                        break
                    yield data
                    remaining -= len(data)
                    
        response = StreamingHttpResponse(
            file_iterator(fullpath, first_byte, length),
            status=206,
            content_type=content_type
        )
        response['Content-Range'] = f'bytes {first_byte}-{last_byte}/{size}'
        response['Content-Length'] = str(length)
        response['Accept-Ranges'] = 'bytes'
        return response

    urlpatterns += [
        re_path(r'^%s(?P<path>.*)$' % re.escape(settings.MEDIA_URL.lstrip('/')), ranged_static_serve, {'document_root': settings.MEDIA_ROOT}),
    ]