"""
Video comparison model
"""
from datetime import datetime
from bson import ObjectId
from typing import List, Optional, Dict, Any
from app.models.database import get_database

class Comparison:
    """Video comparison model"""
    
    COLLECTION_NAME = 'comparisons'
    
    def __init__(self,
                 video_ids: List[ObjectId],
                 comparison_result: str,
                 created_at: Optional[datetime] = None,
                 _id: Optional[ObjectId] = None):
        """
        Initialize Comparison model
        
        Args:
            video_ids: List of video document IDs
            comparison_result: Comparison result text
            created_at: Creation timestamp
            _id: Document ID
        """
        self._id = _id or ObjectId()
        self.video_ids = video_ids
        self.comparison_result = comparison_result
        self.created_at = created_at or datetime.utcnow()
    
    def to_dict(self) -> Dict[str, Any]:
        """Convert to dictionary"""
        return {
            '_id': self._id,
            'video_ids': self.video_ids,
            'comparison_result': self.comparison_result,
            'created_at': self.created_at
        }
    
    @classmethod
    def from_dict(cls, data: Dict[str, Any]) -> 'Comparison':
        """Create Comparison from dictionary"""
        return cls(
            _id=data.get('_id'),
            video_ids=data['video_ids'],
            comparison_result=data['comparison_result'],
            created_at=data.get('created_at')
        )
    
    def save(self) -> ObjectId:
        """Save comparison to database"""
        db = get_database()
        result = db[self.COLLECTION_NAME].insert_one(self.to_dict())
        self._id = result.inserted_id
        return self._id
    
    @classmethod
    def find_by_id(cls, comparison_id: str) -> Optional['Comparison']:
        """Find comparison by ID"""
        db = get_database()
        doc = db[cls.COLLECTION_NAME].find_one({'_id': ObjectId(comparison_id)})
        if doc:
            return cls.from_dict(doc)
        return None