from pywebpush import webpush, WebPushException
import json
from typing import List, Dict, Any
import logging
from urllib.parse import urlparse

from app.config import VAPID_PRIVATE_KEY, VAPID_CLAIMS

logger = logging.getLogger(__name__)

def get_audience(endpoint: str) -> str:
    parsed = urlparse(endpoint)
    return f"{parsed.scheme}://{parsed.netloc}"

class PushService:
    def __init__(self):
        self.vapid_private_key = VAPID_PRIVATE_KEY
        self.vapid_claims = VAPID_CLAIMS

    async def send_notification(self, subscription: Dict[str, Any], payload: Dict[str, Any]) -> bool:
        """
        Envoie une notification push à un abonné spécifique.
        
        Args:
            subscription: Les informations de souscription push
            payload: Le contenu de la notification
            
        Returns:
            bool: True si l'envoi a réussi, False sinon
        """
        try:
            vapid_claims = self.vapid_claims
            vapid_claims["aud"] = get_audience(subscription["endpoint"])
            
            print(f"Envoi de la notification push à {subscription} avec les claims: {vapid_claims}")
            print(f"Payload: {json.dumps(payload)}")

            webpush(
                subscription_info=subscription,
                data=json.dumps(payload),
                vapid_private_key=self.vapid_private_key,
                vapid_claims=vapid_claims,
                verbose=True
            )
            return True
        except WebPushException as e:
            logger.error(f"Erreur lors de l'envoi de la notification push: {str(e)}")
            return False
        except Exception as e:
            logger.error(f"Erreur inattendue lors de l'envoi de la notification push: {str(e)}")
            return False

    async def send_notification_to_all(self, subscriptions: List[Dict[str, Any]], payload: Dict[str, Any]) -> Dict[str, int]:
        """
        Envoie une notification à plusieurs abonnés.
        
        Args:
            subscriptions: Liste des informations de souscription
            payload: Le contenu de la notification
            
        Returns:
            Dict contenant le nombre de succès et d'échecs
        """
        results = {
            "success": 0,
            "failed": 0
        }
        
        for subscription in subscriptions:
            success = await self.send_notification(subscription, payload)
            if success:
                results["success"] += 1
            else:
                results["failed"] += 1
                
        return results

    def create_notification_payload(self, title: str, body: str, icon: str = None) -> Dict[str, Any]:
        """
        Crée un payload de notification standardisé.
        
        Args:
            title: Titre de la notification
            body: Corps du message
            icon: URL de l'icône (optionnel)
            
        Returns:
            Dict contenant le payload formaté
        """
        payload = {
            "notification": {
                "title": title,
                "body": body
            },
            "data": {
                "url": "/map"
            }
        }
        
        if icon:
            payload["notification"]["icon"] = icon
            
        return payload

# Instance singleton du service
push_service = PushService()