class ProcessingTask(Base):
    """Background processing tasks table"""
    __tablename__ = 'processing_tasks'
    
    task_id = Column(String(36), primary_key=True)  # UUID
    status = Column(String(20), default='queued')  # queued, processing, completed, failed
    progress = Column(Float, default=0.0)
    filename = Column(String(255), nullable=False)
    created_at = Column(DateTime, default=datetime.now)
    updated_at = Column(DateTime, default=datetime.now, onupdate=datetime.now)
    completion_time = Column(DateTime, nullable=True)
    
    # Task metadata/results
    user_email = Column(String(100), nullable=True)
    user_department = Column(String(100), nullable=True)
    
    # Store results/errors as JSON
    results = Column(JSON, nullable=True)
    error = Column(String, nullable=True)
    
    # Execution stats
    current_frame = Column(Integer, default=0)
    total_frames = Column(Integer, default=0)
    
    def to_dict(self):
        return {
            'task_id': self.task_id,
            'status': self.status,
            'progress': self.progress,
            'filename': self.filename,
            'created_at': self.created_at.isoformat() if self.created_at else None,
            'updated_at': self.updated_at.isoformat() if self.updated_at else None,
            'completion_time': self.completion_time.isoformat() if self.completion_time else None,
            'results': self.results,
            'error': self.error,
            'current_frame': self.current_frame,
            'total_frames': self.total_frames
        }