"""Server log model for audit trail."""
from datetime import datetime
from typing import Optional

from app.extensions import db


class ServerLog(db.Model):
    """Server log model for tracking system events.
    
    Attributes:
        id: Primary key
        level: Log level (info, warning, error)
        message: Log message content
        timestamp: Event timestamp
    """
    __tablename__ = 'server_log'
    
    id = db.Column(db.Integer, primary_key=True)
    level = db.Column(db.String(20), nullable=False, index=True, default='info')
    message = db.Column(db.Text, nullable=False)
    timestamp = db.Column(db.DateTime, default=datetime.utcnow, 
                         nullable=False, index=True)
    
    def __repr__(self) -> str:
        """String representation of ServerLog."""
        return f'<ServerLog [{self.level.upper()}] {self.message[:50]}>'
    
    @classmethod
    def log_info(cls, message: str) -> 'ServerLog':
        """Create an info level log entry.
        
        Args:
            message: Log message
            
        Returns:
            ServerLog instance
        """
        log = cls(level='info', message=message)
        db.session.add(log)
        db.session.commit()
        return log
    
    @classmethod
    def log_warning(cls, message: str) -> 'ServerLog':
        """Create a warning level log entry.
        
        Args:
            message: Log message
            
        Returns:
            ServerLog instance
        """
        log = cls(level='warning', message=message)
        db.session.add(log)
        db.session.commit()
        return log
    
    @classmethod
    def log_error(cls, message: str) -> 'ServerLog':
        """Create an error level log entry.
        
        Args:
            message: Log message
            
        Returns:
            ServerLog instance
        """
        log = cls(level='error', message=message)
        db.session.add(log)
        db.session.commit()
        return log