#!/usr/bin/env python3

import os
import sys
import logging
import time
import tempfile
from flask import Flask, jsonify
from config import Config
from typing import List, Tuple

# Configure logging with custom handler
class NtfyLogHandler(logging.Handler):
    """Custom logging handler that sends logs to ntfy health backends"""

    def __init__(self, config_obj):
        super().__init__()
        self.config = config_obj

    def emit(self, record):
        """Send log record to health backends"""
        if hasattr(self.config, 'ntfy_backends_health') and self.config.send_all_logs:
            try:
                log_message = self.format(record)
                # Get configured log level or default to WARNING
                min_level = getattr(logging, self.config.log_level.upper(), logging.WARNING)

                if record.levelno >= min_level:
                    # Format message with appropriate emoji based on log level
                    emoji = "🚨" if record.levelno >= logging.ERROR else "⚠️" if record.levelno >= logging.WARNING else "ℹ️"
                    title = f"Emergency Access {record.levelname}"
                    message = f"{emoji} {record.name}: {record.getMessage()}"

                    send_ntfy_notification(
                        self.config.ntfy_backends_health,
                        message,
                        title
                    )
            except Exception:
                # Don't fail the application if logging notification fails
                pass

# Configure logging
logging.basicConfig(
    level=logging.INFO,
    format='%(asctime)s - %(name)s - %(levelname)s - %(message)s',
    handlers=[
        logging.FileHandler('/var/log/emergency-access.log'),
        logging.StreamHandler()
    ]
)
logger = logging.getLogger(__name__)

app = Flask(__name__)

# Global config instance
config = None

def send_ntfy_notification(backends: List[str], message: str, title: str = None) -> Tuple[bool, List[str]]:
    """
    Send notification using dschep/ntfy with dedicated config file
    Returns: (success, successful_backends)
    """
    successful_backends = []

    for backend in backends:
        try:
            # Import ntfy here to avoid import issues during startup
            import ntfy

            # Load the ntfy config file
            ntfy_config = ntfy.load_config(config.ntfy_config_path)

            # Send notification using the backend name from our config file
            if title:
                ntfy.notify(message, title=title, backend=backend, config=ntfy_config)
            else:
                ntfy.notify(message, backend=backend, config=ntfy_config)

            successful_backends.append(backend)
            logger.info(f"Notification sent successfully via {backend}")

        except ImportError:
            logger.error(f"ntfy package not available for backend {backend}")
        except Exception as e:
            logger.error(f"Failed to send notification to {backend}: {str(e)}")

    success = len(successful_backends) > 0
    return success, successful_backends

def read_file_safely(file_path: str) -> Tuple[bool, str]:
    """
    Safely read file content
    Returns: (success, content)
    """
    try:
        if not os.path.exists(file_path):
            logger.error(f"File not found: {file_path}")
            return False, f"File not found: {file_path}"

        with open(file_path, 'r') as f:
            content = f.read().strip()

        if not content:
            logger.error(f"File is empty: {file_path}")
            return False, f"File is empty: {file_path}"

        return True, content

    except PermissionError:
        logger.error(f"Permission denied reading file: {file_path}")
        return False, f"Permission denied: {file_path}"
    except Exception as e:
        logger.error(f"Failed to read file {file_path}: {str(e)}")
        return False, f"Failed to read file: {str(e)}"

def get_key_part():
    """Emergency key access endpoint"""
    logger.warning("EMERGENCY: Key access attempt detected")

    try:
        # Send notification first - fail-safe approach
        notification_success, successful_backends = send_ntfy_notification(
            config.ntfy_backends_key,
            config.ntfy_key_message,
            "EMERGENCY ACCESS ALERT"
        )

        if not notification_success:
            logger.error("CRITICAL: Failed to send notifications to any backend")
            return jsonify({
                'error': 'Notification system failure',
                'message': 'Access denied for security reasons'
            }), 500

        logger.info(f"Notifications sent successfully to: {successful_backends}")

        # Read key file
        file_success, content = read_file_safely(config.key_file_path)

        if not file_success:
            logger.error(f"CRITICAL: Failed to read key file: {content}")
            return jsonify({
                'error': 'File access failure',
                'message': 'Unable to retrieve key part'
            }), 500

        logger.warning("EMERGENCY: Key part successfully retrieved and sent")
        return jsonify({
            'success': True,
            'key_part': content,
            'timestamp': time.time(),
            'notified_backends': successful_backends
        })

    except Exception as e:
        logger.error(f"CRITICAL: Unexpected error in key access: {str(e)}")
        return jsonify({
            'error': 'System error',
            'message': 'Internal server error'
        }), 500

def health_check():
    """Health check endpoint with dummy file access"""
    logger.info("Health check requested")

    try:
        # Send notification
        notification_success, successful_backends = send_ntfy_notification(
            config.ntfy_backends_health,
            config.ntfy_health_message,
            "Health Check"
        )

        if not notification_success:
            logger.error("Health check notification failed")
            return jsonify({
                'status': 'error',
                'message': 'Notification system failure'
            }), 500

        # Read dummy file
        file_success, content = read_file_safely(config.dummy_file_path)

        if not file_success:
            logger.error(f"Health check file read failed: {content}")
            return jsonify({
                'status': 'error',
                'message': 'File system failure'
            }), 500

        logger.info("Health check completed successfully")
        return jsonify({
            'status': 'ok',
            'timestamp': time.time(),
            'notified_backends': successful_backends,
            'dummy_content_length': len(content)
        })

    except Exception as e:
        logger.error(f"Health check error: {str(e)}")
        return jsonify({
            'status': 'error',
            'message': 'System error'
        }), 500

@app.errorhandler(404)
def not_found(error):
    """Handle 404 errors silently for security"""
    logger.warning(f"404 attempt: {error}")
    return jsonify({'error': 'Not found'}), 404

@app.errorhandler(500)
def internal_error(error):
    """Handle internal server errors"""
    logger.error(f"Internal server error: {error}")
    return jsonify({'error': 'Internal server error'}), 500

def validate_setup():
    """Validate system setup before starting"""
    logger.info("Validating system setup...")

    # Check config files exist
    if not os.path.exists(config.key_file_path):
        logger.error(f"Key file not found: {config.key_file_path}")
        return False

    if not os.path.exists(config.dummy_file_path):
        logger.error(f"Dummy file not found: {config.dummy_file_path}")
        return False

    # Test file permissions
    try:
        with open(config.key_file_path, 'r') as f:
            f.read(1)
        with open(config.dummy_file_path, 'r') as f:
            f.read(1)
    except Exception as e:
        logger.error(f"File permission test failed: {str(e)}")
        return False

    # Test notification system
    logger.info("Testing notification system...")
    try:
        key_success, _ = send_ntfy_notification(
            config.ntfy_backends_key[:1],  # Test only first backend
            "System startup test - key notifications",
            "Emergency Access Startup Test"
        )
        health_success, _ = send_ntfy_notification(
            config.ntfy_backends_health[:1],  # Test only first backend
            "System startup test - health notifications",
            "Emergency Access Startup Test"
        )

        if not key_success:
            logger.error("Key notification system test failed")
            return False

        if not health_success:
            logger.error("Health notification system test failed")
            return False
    except Exception as e:
        logger.warning(f"Notification test failed, but continuing: {str(e)}")

    logger.info("System validation completed successfully")
    return True

if __name__ == '__main__':
    try:
        # Load configuration
        config = Config()
        logger.info("Configuration loaded successfully")

        # Add ntfy log handler after config is loaded
        if config.send_all_logs:
            ntfy_handler = NtfyLogHandler(config)
            min_level = getattr(logging, config.log_level.upper(), logging.WARNING)
            ntfy_handler.setLevel(min_level)
            # Add to root logger to catch all application logs
            logging.getLogger().addHandler(ntfy_handler)

        # Validate system setup
        if not validate_setup():
            logger.error("System validation failed, exiting")
            sys.exit(1)

        # Add Flask routes with config values
        app.add_url_rule(config.key_route, 'get_key_part', get_key_part, methods=['GET'])
        app.add_url_rule(config.health_route, 'health_check', health_check, methods=['GET'])

        logger.info(f"Starting emergency access server on {config.server_host}:{config.server_port}")
        logger.info(f"Key route: {config.key_route}")
        logger.info(f"Health route: {config.health_route}")

        # Run the server on local port for Caddy reverse proxy
        app.run(
            host=config.server_host,
            port=config.server_port,
            debug=False,
            threaded=True
        )

    except Exception as e:
        logger.error(f"Failed to start server: {str(e)}")
        sys.exit(1)