"""
Notifications API routes.
"""
from typing import List, Optional
import csv
from datetime import datetime
from ninja import Router
from ninja_jwt.authentication import JWTAuth
from ninja.pagination import paginate, PageNumberPagination
from django.shortcuts import get_object_or_404
from django.http import HttpResponse
from django.utils import timezone

from .models import Notification
from .utils import get_notification_preference
from .schemas import (
    NotificationOut,
    UnreadCountOut,
    MessageOut,
    NotificationPreferenceOut,
    NotificationPreferenceIn,
)

router = Router()


@router.get("/", response=List[NotificationOut], auth=JWTAuth())
@paginate(PageNumberPagination, page_size=20)
def list_notifications(
    request,
    is_read: Optional[bool] = None,
    type: Optional[str] = None,
    start: Optional[datetime] = None,
    end: Optional[datetime] = None,
):
    """Get current user's notifications."""
    queryset = Notification.objects.filter(user=request.auth)
    
    if is_read is not None:
        queryset = queryset.filter(is_read=is_read)
    if type:
        queryset = queryset.filter(type=type)
    if start:
        queryset = queryset.filter(created_at__gte=start)
    if end:
        queryset = queryset.filter(created_at__lte=end)
    
    return [
        NotificationOut(
            id=n.id,
            user_id=n.user_id,
            type=n.type,
            title=n.title,
            content=n.content,
            related_id=n.related_id,
            related_type=n.related_type,
            is_read=n.is_read,
            created_at=n.created_at,
        )
        for n in queryset
    ]


@router.get("/preferences/", response=NotificationPreferenceOut, auth=JWTAuth())
def get_preferences(request):
    """Get current user's notification preferences."""
    preference = get_notification_preference(request.auth)
    return NotificationPreferenceOut(
        user_id=preference.user_id,
        enable_bounty=preference.enable_bounty,
        enable_price_alert=preference.enable_price_alert,
        enable_system=preference.enable_system,
        updated_at=preference.updated_at,
    )


@router.patch("/preferences/", response=NotificationPreferenceOut, auth=JWTAuth())
def update_preferences(request, data: NotificationPreferenceIn):
    """Update notification preferences."""
    preference = get_notification_preference(request.auth)
    update_data = data.dict(exclude_unset=True)
    for key, value in update_data.items():
        setattr(preference, key, value)
    preference.save()
    return NotificationPreferenceOut(
        user_id=preference.user_id,
        enable_bounty=preference.enable_bounty,
        enable_price_alert=preference.enable_price_alert,
        enable_system=preference.enable_system,
        updated_at=preference.updated_at,
    )


@router.get("/unread-count/", response=UnreadCountOut, auth=JWTAuth())
def get_unread_count(request):
    """Get count of unread notifications."""
    count = Notification.objects.filter(user=request.auth, is_read=False).count()
    return UnreadCountOut(count=count)


@router.get("/export/", auth=JWTAuth())
def export_notifications_csv(request):
    """Export current user's notifications to CSV."""
    notifications = Notification.objects.filter(user=request.auth).order_by("-created_at")
    response = HttpResponse(content_type="text/csv; charset=utf-8")
    filename = f'notifications_{timezone.now().strftime("%Y%m%d_%H%M%S")}.csv'
    response["Content-Disposition"] = f'attachment; filename="{filename}"'
    response.write("\ufeff")

    writer = csv.writer(response)
    writer.writerow(["created_at", "type", "title", "content", "is_read"])
    for notification in notifications:
        writer.writerow(
            [
                notification.created_at.isoformat(),
                notification.type,
                notification.title,
                notification.content or "",
                "true" if notification.is_read else "false",
            ]
        )

    return response


@router.post("/{notification_id}/read/", response=MessageOut, auth=JWTAuth())
def mark_as_read(request, notification_id: int):
    """Mark a notification as read."""
    notification = get_object_or_404(
        Notification,
        id=notification_id,
        user=request.auth
    )
    notification.is_read = True
    notification.save()
    return MessageOut(message="已标记为已读", success=True)


@router.post("/read-all/", response=MessageOut, auth=JWTAuth())
def mark_all_as_read(request):
    """Mark all notifications as read."""
    Notification.objects.filter(user=request.auth, is_read=False).update(is_read=True)
    return MessageOut(message="已全部标记为已读", success=True)


@router.delete("/{notification_id}", response=MessageOut, auth=JWTAuth())
def delete_notification(request, notification_id: int):
    """Delete a notification."""
    notification = get_object_or_404(
        Notification,
        id=notification_id,
        user=request.auth
    )
    notification.delete()
    return MessageOut(message="通知已删除", success=True)


@router.delete("/", response=MessageOut, auth=JWTAuth())
def delete_all_read(request):
    """Delete all read notifications."""
    Notification.objects.filter(user=request.auth, is_read=True).delete()
    return MessageOut(message="已删除所有已读通知", success=True)