"""Notification routes — FCM token registration and reminder settings."""
import logging
from fastapi import APIRouter, HTTPException, Depends
from db import get_database
from pydantic import BaseModel
from typing import Optional
from datetime import datetime
from auth import get_current_user, verify_user_access

log = logging.getLogger(__name__)
router = APIRouter()


class FcmTokenRequest(BaseModel):
    userId: str
    fcmToken: str


class ReminderSettingsRequest(BaseModel):
    time: Optional[str] = None      # "HH:MM" in 24-hour format
    enabled: bool
    timezone: Optional[str] = None  # IANA timezone, e.g. "Asia/Kolkata"


@router.post("/fcm-token", response_model=dict)
async def register_fcm_token(body: FcmTokenRequest, token: dict = Depends(get_current_user)):
    """
    Register (or refresh) an FCM device token for a user.
    Stores unique tokens per user — duplicate tokens are ignored.
    """
    db = get_database()
    try:
        user = verify_user_access(body.userId, db, token)
        user_oid = user["_id"]

        db.users.update_one(
            {"_id": user_oid},
            {
                "$addToSet": {"fcmTokens": body.fcmToken},
                "$set": {"updatedAt": datetime.utcnow()},
            }
        )
        return {"message": "FCM token registered"}
    except HTTPException:
        raise
    except Exception:
        log.exception("Failed to register FCM token")
        raise HTTPException(status_code=500, detail="Internal server error")


@router.put("/reminder/{user_id}", response_model=dict)
async def update_reminder(user_id: str, settings: ReminderSettingsRequest, token: dict = Depends(get_current_user)):
    """Save or update daily reminder settings for a user."""
    db = get_database()
    try:
        user = verify_user_access(user_id, db, token)
        user_oid = user["_id"]

        reminder_update: dict = {"reminder.enabled": settings.enabled}
        if settings.time is not None:
            reminder_update["reminder.time"] = settings.time
        if settings.timezone is not None:
            reminder_update["reminder.timezone"] = settings.timezone

        db.users.update_one(
            {"_id": user_oid},
            {"$set": {**reminder_update, "updatedAt": datetime.utcnow()}}
        )
        return {"message": "Reminder settings updated"}
    except HTTPException:
        raise
    except Exception:
        log.exception("Failed to update reminder settings")
        raise HTTPException(status_code=500, detail="Internal server error")