from app.core.nosql_client import db
from datetime import datetime
from typing import List, Optional, Dict, Any
import uuid
import logging

from app.utils.db import prepare_for_db

logger = logging.getLogger(__name__)

class PetModel:
    """Model for managing pet profiles embedded under customer documents"""
    
    @staticmethod
    async def create_pet(
        customer_id: str,
        pet_data: dict
    ) -> Optional[str]:
        """Create a new embedded pet profile under a user in customers collection"""
        try:
            from app.models.user_model import BookMyServiceUserModel
            user = await BookMyServiceUserModel.collection.find_one({"customer_id": customer_id})
            if not user:
                logger.error(f"User not found for customer_id {customer_id}")
                return None

            pet_id = str(uuid.uuid4())
            current_time = datetime.utcnow()

            pet_doc = {
                "pet_id": pet_id,
                "pet_name": pet_data.get('pet_name'),
                "species": getattr(pet_data.get('species'), 'value', pet_data.get('species')),
                "breed": pet_data.get('breed'),
                "date_of_birth": pet_data.get('date_of_birth'),
                "age": pet_data.get('age'),
                "weight": pet_data.get('weight'),
                "gender": getattr(pet_data.get('gender'), 'value', pet_data.get('gender')),
                "temperament": getattr(pet_data.get('temperament'), 'value', pet_data.get('temperament')),
                "health_notes": pet_data.get('health_notes'),
                "is_vaccinated": pet_data.get('is_vaccinated'),
                "pet_photo_url": pet_data.get('pet_photo_url'),
                "is_default": pet_data.get('is_default', False),
                "created_at": current_time,
                "updated_at": current_time
            }

            pets = user.get("pets", [])
            if pet_doc.get("is_default"):
                for existing in pets:
                    if existing.get("is_default"):
                        existing["is_default"] = False
                        existing["updated_at"] = current_time
            else:
                if len(pets) == 0:
                    pet_doc["is_default"] = True
            pets.append(pet_doc)

            # Sanitize pets list for MongoDB (convert date to datetime, etc.)
            sanitized_pets = prepare_for_db(pets)
            update_res = await BookMyServiceUserModel.collection.update_one(
                {"customer_id": customer_id},
                {"$set": {"pets": sanitized_pets}}
            )

            if update_res.modified_count > 0:
                logger.info(f"Embedded pet created successfully: {pet_id} for user: {customer_id}")
                return pet_id
            else:
                logger.info(f"Embedded pet creation attempted with no modified_count for user: {customer_id}")
                return pet_id

        except Exception as e:
            logger.error(f"Error creating embedded pet for user {customer_id}: {str(e)}")
            return None
    
    @staticmethod
    async def get_user_pets(customer_id: str) -> List[Dict[str, Any]]:
        """Get all embedded pets for a specific user from customers collection"""
        try:
            from app.models.user_model import BookMyServiceUserModel
            user = await BookMyServiceUserModel.collection.find_one({"customer_id": customer_id})
            if not user:
                return []

            pets = user.get("pets", [])
            pets.sort(key=lambda x: x.get("created_at", datetime.utcnow()), reverse=True)
            for p in pets:
                p["customer_id"] = customer_id
            logger.info(f"Retrieved {len(pets)} embedded pets for user: {customer_id}")
            return pets

        except Exception as e:
            logger.error(f"Error getting embedded pets for user {customer_id}: {str(e)}")
            return []
    
    @staticmethod
    async def get_pet_by_id(customer_id: str, pet_id: str) -> Optional[Dict[str, Any]]:
        """Get a specific embedded pet by ID for a user"""
        try:
            from app.models.user_model import BookMyServiceUserModel
            user = await BookMyServiceUserModel.collection.find_one({"customer_id": customer_id})
            if not user:
                return None

            pets = user.get("pets", [])
            for p in pets:
                if p.get("pet_id") == pet_id:
                    p_copy = dict(p)
                    p_copy["customer_id"] = customer_id
                    logger.info(f"Embedded pet found: {pet_id} for user: {customer_id}")
                    return p_copy
            logger.warning(f"Embedded pet not found: {pet_id} for user: {customer_id}")
            return None

        except Exception as e:
            logger.error(f"Error getting embedded pet {pet_id} for user {customer_id}: {str(e)}")
            return None
    
    @staticmethod
    async def update_pet(customer_id: str, pet_id: str, update_fields: Dict[str, Any]) -> bool:
        """Update an embedded pet's information under a user"""
        try:
            from app.models.user_model import BookMyServiceUserModel
            user = await BookMyServiceUserModel.collection.find_one({"customer_id": customer_id})
            if not user:
                return False

            pets = user.get("pets", [])
            updated = False

            for idx, p in enumerate(pets):
                if p.get("pet_id") == pet_id:
                    normalized_updates: Dict[str, Any] = {}
                    for k, v in update_fields.items():
                        if hasattr(v, "value"):
                            normalized_updates[k] = v.value
                        else:
                            normalized_updates[k] = v

                    normalized_updates["updated_at"] = datetime.utcnow()
                    pets[idx] = {**p, **normalized_updates}
                    updated = True
                    if update_fields.get("is_default"):
                        for j, other in enumerate(pets):
                            if other.get("pet_id") != pet_id and other.get("is_default"):
                                other["is_default"] = False
                                other["updated_at"] = datetime.utcnow()
                                pets[j] = other
                    break

            if not updated:
                logger.warning(f"Embedded pet not found for update: {pet_id} (user {customer_id})")
                return False

            # Sanitize pets list for MongoDB
            sanitized_pets = prepare_for_db(pets)
            result = await BookMyServiceUserModel.collection.update_one(
                {"customer_id": customer_id},
                {"$set": {"pets": sanitized_pets}}
            )

            if result.modified_count > 0:
                logger.info(f"Embedded pet updated successfully: {pet_id} (user {customer_id})")
                return True
            else:
                logger.info(f"Embedded pet update applied with no modified_count: {pet_id} (user {customer_id})")
                return True

        except Exception as e:
            logger.error(f"Error updating embedded pet {pet_id} for user {customer_id}: {str(e)}")
            return False
    
    @staticmethod
    async def delete_pet(customer_id: str, pet_id: str) -> bool:
        """Delete an embedded pet profile under a user"""
        try:
            from app.models.user_model import BookMyServiceUserModel
            user = await BookMyServiceUserModel.collection.find_one({"customer_id": customer_id})
            if not user:
                return False

            pets = user.get("pets", [])
            new_pets = [p for p in pets if p.get("pet_id") != pet_id]
            if len(new_pets) == len(pets):
                logger.warning(f"Embedded pet not found for deletion: {pet_id} (user {customer_id})")
                return False

            # Sanitize pets list for MongoDB
            sanitized_new_pets = prepare_for_db(new_pets)
            result = await BookMyServiceUserModel.collection.update_one(
                {"customer_id": customer_id},
                {"$set": {"pets": sanitized_new_pets}}
            )

            if result.modified_count > 0:
                logger.info(f"Embedded pet deleted successfully: {pet_id} (user {customer_id})")
                return True
            else:
                logger.info(f"Embedded pet deletion applied with no modified_count: {pet_id} (user {customer_id})")
                return True

        except Exception as e:
            logger.error(f"Error deleting embedded pet {pet_id} for user {customer_id}: {str(e)}")
            return False
    
    @staticmethod
    async def get_pet_count_for_user(customer_id: str) -> int:
        """Get the total number of embedded pets for a user"""
        try:
            from app.models.user_model import BookMyServiceUserModel
            user = await BookMyServiceUserModel.collection.find_one({"customer_id": customer_id})
            if not user:
                return 0
            return len(user.get("pets", []))
        except Exception as e:
            logger.error(f"Error counting embedded pets for user {customer_id}: {str(e)}")
            return 0

    @staticmethod
    async def get_default_pet(customer_id: str) -> Optional[Dict[str, Any]]:
        """Get the default pet for a user"""
        try:
            from app.models.user_model import BookMyServiceUserModel
            user = await BookMyServiceUserModel.collection.find_one({"customer_id": customer_id})
            if not user:
                return None
            pets = user.get("pets", [])
            for p in pets:
                if p.get("is_default"):
                    p_copy = dict(p)
                    p_copy["customer_id"] = customer_id
                    return p_copy
            return None
        except Exception as e:
            logger.error(f"Error getting default pet for user {customer_id}: {str(e)}")
            return None

    @staticmethod
    async def set_default_pet(customer_id: str, pet_id: str) -> bool:
        """Set a pet as default for a user, unsetting any existing default"""
        try:
            from app.models.user_model import BookMyServiceUserModel
            user = await BookMyServiceUserModel.collection.find_one({"customer_id": customer_id})
            if not user:
                return False
            pets = user.get("pets", [])
            found = False
            now = datetime.utcnow()
            for p in pets:
                if p.get("pet_id") == pet_id:
                    p["is_default"] = True
                    p["updated_at"] = now
                    found = True
                else:
                    if p.get("is_default"):
                        p["is_default"] = False
                        p["updated_at"] = now
            if not found:
                return False
            # Sanitize pets list for MongoDB
            sanitized_pets = prepare_for_db(pets)
            res = await BookMyServiceUserModel.collection.update_one(
                {"customer_id": customer_id},
                {"$set": {"pets": sanitized_pets}}
            )
            return True
        except Exception as e:
            logger.error(f"Error setting default pet {pet_id} for user {customer_id}: {str(e)}")
            return False