#!/usr/bin/env python3
"""
Standalone metrics server for testing.
Run this to start just the metrics system without the bot.
"""

import asyncio
import signal
import sys
from helper_bot.utils.metrics_exporter import MetricsManager


class MetricsServer:
    """Standalone metrics server."""
    
    def __init__(self, host: str = "0.0.0.0", port: int = 8000):
        self.host = host
        self.port = port
        self.metrics_manager = MetricsManager(host, port)
        self.running = False
        
    async def start(self):
        """Start the metrics server."""
        try:
            await self.metrics_manager.start()
            self.running = True
            print(f"🚀 Metrics server started on {self.host}:{self.port}")
            print(f"📊 Metrics endpoint: http://{self.host}:{self.port}/metrics")
            print(f"🏥 Health check: http://{self.host}:{self.port}/health")
            print(f"ℹ️  Info: http://{self.host}:{self.port}/")
            print("\nPress Ctrl+C to stop the server")
            
            # Keep the server running
            while self.running:
                await asyncio.sleep(1)
                
        except Exception as e:
            print(f"❌ Error starting metrics server: {e}")
            raise
    
    async def stop(self):
        """Stop the metrics server."""
        if self.running:
            self.running = False
            await self.metrics_manager.stop()
            print("\n🛑 Metrics server stopped")
    
    def signal_handler(self, signum, frame):
        """Handle shutdown signals."""
        print(f"\n📡 Received signal {signum}, shutting down...")
        asyncio.create_task(self.stop())


async def main():
    """Main function."""
    # Parse command line arguments
    host = "0.0.0.0"
    port = 8000
    
    if len(sys.argv) > 1:
        host = sys.argv[1]
    if len(sys.argv) > 2:
        port = int(sys.argv[2])
    
    # Create and start server
    server = MetricsServer(host, port)
    
    # Setup signal handlers
    signal.signal(signal.SIGINT, server.signal_handler)
    signal.signal(signal.SIGTERM, server.signal_handler)
    
    try:
        await server.start()
    except KeyboardInterrupt:
        print("\n📡 Keyboard interrupt received")
    finally:
        await server.stop()


if __name__ == "__main__":
    print("🔧 Starting standalone metrics server...")
    print("Usage: python run_metrics_only.py [host] [port]")
    print("Default: host=0.0.0.0, port=8000")
    print()
    
    try:
        asyncio.run(main())
    except KeyboardInterrupt:
        print("\n🛑 Server stopped by user")
    except Exception as e:
        print(f"❌ Server error: {e}")
        sys.exit(1)