"""
FastAPI Application Server Entry Point
This module provides a server entry point for the FastAPI application defined in app.py.
"""

import logging
import os
import sys
import argparse
import webbrowser
import socket
import uvicorn

# Import from backend modules
from backend.server_config import PORT, HOST, MAX_PORT_ATTEMPTS, LOG_LEVEL, ensure_directories
from backend.app import app  # Import the FastAPI app from app.py

# Setup logging
logging.basicConfig(
    level=getattr(logging, LOG_LEVEL),
    format="%(asctime)s - %(name)s - %(levelname)s - %(message)s",
    datefmt="%Y-%m-%d %H:%M:%S"
)
logger = logging.getLogger("agent_monitoring_server")


def find_available_port(start_port: int, max_attempts: int) -> int:
    """Find an available port starting from the given port"""
    for port_offset in range(max_attempts):
        port = start_port + port_offset
        try:
            with socket.socket(socket.AF_INET, socket.SOCK_STREAM) as s:
                s.bind((HOST, port))
                logger.info(f"Found available port: {port}")
                return port
        except OSError:
            logger.debug(f"Port {port} is not available")
            continue
    
    # If we reach here, try some common alternative ports
    alternative_ports = [8080, 8000, 3000, 9000, 5000]
    for port in alternative_ports:
        try:
            with socket.socket(socket.AF_INET, socket.SOCK_STREAM) as s:
                s.bind((HOST, port))
                logger.info(f"Found available alternative port: {port}")
                return port
        except OSError:
            continue
    
    # If still no port found, raise an error
    raise RuntimeError(
        f"Could not find an available port after trying {max_attempts} "
        f"sequential ports and {len(alternative_ports)} alternatives"
    )


def parse_arguments():
    """Parse command line arguments"""
    parser = argparse.ArgumentParser(description="Agent Monitoring System Server")
    parser.add_argument("--port", type=int, default=PORT, help=f"Server port (default: {PORT})")
    parser.add_argument("--host", default=HOST, help=f"Server host (default: {HOST})")
    parser.add_argument("--log-level", default=LOG_LEVEL, help=f"Log level (default: {LOG_LEVEL})")
    parser.add_argument("--no-open-browser", action="store_true", help="Do not open browser automatically")
    
    return parser.parse_args()


def main():
    """Main entry point for running the server"""
    # Parse command line arguments
    args = parse_arguments()
    
    # Ensure required directories exist
    ensure_directories()
    
    # Find an available port
    try:
        port = find_available_port(args.port, MAX_PORT_ATTEMPTS)
    except RuntimeError as e:
        logger.error(str(e))
        sys.exit(1)
    
    # Log startup message
    logger.info(f"Starting Agent Monitoring System server on {args.host}:{port}")
    
    # Open browser if not disabled
    if not args.no_open_browser:
        webbrowser.open(f"http://{args.host}:{port}")
    
    # Start the server
    try:
        uvicorn.run(
            "backend.app:app",  # Update to use app.py instead of main.py
            host=args.host,
            port=port,
            log_level=args.log_level.lower(),
            reload=False
        )
    except KeyboardInterrupt:
        logger.info("Server stopped by user")
    except Exception as e:
        logger.error(f"Error running server: {str(e)}")
        sys.exit(1)


if __name__ == "__main__":
    main()