#!/usr/bin/env python3
"""
Routing Manager for Personal Internet Cell
Handles VPN gateway, NAT, iptables, and advanced routing

NOTE: This manager runs iptables/ip-route commands on the HOST (the machine running
docker-compose), not inside cell-wireguard. This is intentional for host-level
routing features (exit-node, bridge, split-route) that are not yet wired to any
UI endpoint. The manager is instantiated but its methods are not called by any
active API route.

CRITICAL: _remove_nat_rule flushes ALL of POSTROUTING (-F), which would wipe the
WireGuard MASQUERADE rule. Do not call it until this is fixed to use targeted
rule deletion (-D) instead of a full flush.
"""

import os
import json
import subprocess
import logging
import ipaddress
import time
from datetime import datetime
from typing import Dict, List, Optional, Tuple, Any
import re
from base_service_manager import BaseServiceManager

logger = logging.getLogger(__name__)

class RoutingManager(BaseServiceManager):
    """Manages VPN gateway, NAT, and routing functionality"""
    
    def __init__(self, data_dir: str = '/app/data', config_dir: str = '/app/config'):
        super().__init__('routing', data_dir, config_dir)
        self.routing_dir = os.path.join(config_dir, 'routing')
        self.rules_file = os.path.join(data_dir, 'routing', 'rules.json')
        
        # Service state tracking
        self._service_running = False
        self._state_file = os.path.join(data_dir, 'routing', 'service_state.json')
        
        # Ensure directories exist
        self.safe_makedirs(self.routing_dir)
        self.safe_makedirs(os.path.dirname(self.rules_file))
        
        # Initialize routing configuration
        self._ensure_config_exists()
        
        # Load service state
        self._load_service_state()
    
    def _ensure_config_exists(self):
        """Ensure routing configuration exists"""
        try:
            if not os.path.exists(self.rules_file):
                self._initialize_rules()
        except (PermissionError, OSError):
            pass
    
    def _initialize_rules(self):
        """Initialize routing rules"""
        default_rules = {
            'nat_rules': [],
            'forwarding_rules': [],
            'peer_routes': {},
            'exit_nodes': [],
            'bridge_routes': [],
            'split_routes': [],
            'firewall_rules': []
        }
        
        with open(self.rules_file, 'w') as f:
            json.dump(default_rules, f, indent=2)
        
        logger.info("Routing rules initialized")
    
    def _load_service_state(self):
        """Load service state from file"""
        try:
            if os.path.exists(self._state_file):
                with open(self._state_file, 'r') as f:
                    state = json.load(f)
                    self._service_running = state.get('running', False)
            else:
                # Default to running if no state file exists (for backward compatibility)
                self._service_running = True
                self._save_service_state()
        except Exception as e:
            logger.error(f"Failed to load service state: {e}")
            self._service_running = True
    
    def _save_service_state(self):
        """Save service state to file"""
        try:
            state = {
                'running': self._service_running,
                'timestamp': datetime.utcnow().isoformat()
            }
            with open(self._state_file, 'w') as f:
                json.dump(state, f, indent=2)
        except Exception as e:
            logger.error(f"Failed to save service state: {e}")
    
    def _validate_cidr(self, cidr):
        import ipaddress
        try:
            ipaddress.ip_network(cidr)
            return True
        except Exception:
            return False

    def add_nat_rule(self, source_network: str, target_interface: str, masquerade: bool = True, nat_type: str = 'MASQUERADE', protocol: str = 'ALL', external_port: str = None, internal_ip: str = None, internal_port: str = None) -> bool:
        """Add NAT rule for network translation, port forwarding, or 1:1 NAT."""
        # Validation
        if not source_network or not self._validate_cidr(source_network):
            logger.error(f"Invalid source_network: {source_network}")
            return False
        if not target_interface or not isinstance(target_interface, str):
            logger.error(f"Invalid target_interface: {target_interface}")
            return False
        if nat_type not in ['MASQUERADE', 'SNAT', 'DNAT']:
            logger.error(f"Invalid nat_type: {nat_type}")
            return False
        if protocol not in ['TCP', 'UDP', 'ALL']:
            logger.error(f"Invalid protocol: {protocol}")
            return False
        try:
            rules = self._load_rules()
            nat_rule = {
                'id': f"nat_{len(rules['nat_rules']) + 1}",
                'source_network': source_network,
                'target_interface': target_interface,
                'masquerade': masquerade,
                'nat_type': nat_type,
                'protocol': protocol,
                'external_port': external_port,
                'internal_ip': internal_ip,
                'internal_port': internal_port,
                'enabled': True,
                'created_at': datetime.now().isoformat()
            }
            rules['nat_rules'].append(nat_rule)
            self._save_rules(rules)
            self._apply_nat_rule(nat_rule)
            logger.info(f"Added NAT rule for {source_network} -> {target_interface} type={nat_type}")
            return True
        except Exception as e:
            logger.error(f"Failed to add NAT rule: {e}")
            return False
    
    def remove_nat_rule(self, rule_id: str) -> bool:
        """Remove NAT rule"""
        try:
            rules = self._load_rules()
            
            # Find and remove rule
            rules['nat_rules'] = [rule for rule in rules['nat_rules'] if rule['id'] != rule_id]
            self._save_rules(rules)
            
            # Remove from iptables
            self._remove_nat_rule(rule_id)
            
            logger.info(f"Removed NAT rule {rule_id}")
            return True
            
        except Exception as e:
            logger.error(f"Failed to remove NAT rule: {e}")
            return False
    
    def add_peer_route(self, peer_name: str, peer_ip: str, allowed_networks: list, route_type: str = 'lan') -> bool:
        """Add routing rule for a peer"""
        # Validation
        if not peer_name or not isinstance(peer_name, str):
            logger.error(f"Invalid peer_name: {peer_name}")
            return False
        if not peer_ip or not isinstance(peer_ip, str):
            logger.error(f"Invalid peer_ip: {peer_ip}")
            return False
        if not allowed_networks or not isinstance(allowed_networks, list) or not all(self._validate_cidr(n) for n in allowed_networks):
            logger.error(f"Invalid allowed_networks: {allowed_networks}")
            return False
        if route_type not in ['lan', 'exit', 'bridge', 'split']:
            logger.error(f"Invalid route_type: {route_type}")
            return False
        try:
            rules = self._load_rules()
            peer_route = {
                'peer_name': peer_name,
                'peer_ip': peer_ip,
                'allowed_networks': allowed_networks,
                'route_type': route_type,
                'enabled': True,
                'created_at': datetime.now().isoformat()
            }
            rules['peer_routes'][peer_name] = peer_route
            self._save_rules(rules)
            self._apply_peer_route(peer_route)
            logger.info(f"Added peer route for {peer_name}")
            return True
        except Exception as e:
            logger.error(f"Failed to add peer route: {e}")
            return False
    
    def remove_peer_route(self, peer_name: str) -> bool:
        """Remove routing rule for a peer"""
        try:
            rules = self._load_rules()
            
            if peer_name in rules['peer_routes']:
                del rules['peer_routes'][peer_name]
                self._save_rules(rules)
                
                # Remove from routing table
                self._remove_peer_route(peer_name)
                
                logger.info(f"Removed peer route for {peer_name}")
                return True
            
            return False
            
        except Exception as e:
            logger.error(f"Failed to remove peer route: {e}")
            return False
    
    def add_exit_node(self, peer_name: str, peer_ip: str, allowed_domains: List[str] = None) -> bool:
        """Add exit node configuration"""
        # Validation — peer_ip flows into `ip route add default via <peer_ip>`; argv
        # injection / shell-meta in name would reach iptables/ip via _apply_exit_node.
        if not isinstance(peer_name, str) or not re.match(r'^[a-zA-Z0-9_.-]{1,64}$', peer_name):
            logger.error(f"add_exit_node: invalid peer_name {peer_name!r}")
            return {'success': False, 'error': f'invalid input: peer_name {peer_name!r}'}
        try:
            ipaddress.ip_address(peer_ip)
        except (ValueError, TypeError):
            logger.error(f"add_exit_node: invalid peer_ip {peer_ip!r}")
            return {'success': False, 'error': f'invalid input: peer_ip {peer_ip!r}'}
        if allowed_domains is not None:
            if not isinstance(allowed_domains, list):
                return {'success': False, 'error': 'invalid input: allowed_domains must be a list'}
            for d in allowed_domains:
                if not isinstance(d, str) or not re.match(r'^[a-zA-Z0-9][a-zA-Z0-9.-]{0,252}$', d):
                    return {'success': False, 'error': f'invalid input: domain {d!r}'}
        try:
            rules = self._load_rules()
            
            exit_node = {
                'peer_name': peer_name,
                'peer_ip': peer_ip,
                'allowed_domains': allowed_domains or [],
                'enabled': True,
                'created_at': datetime.now().isoformat()
            }
            
            rules['exit_nodes'].append(exit_node)
            self._save_rules(rules)
            
            # Apply exit node rules
            self._apply_exit_node(exit_node)
            
            logger.info(f"Added exit node {peer_name}")
            return True
            
        except Exception as e:
            logger.error(f"Failed to add exit node: {e}")
            return False
    
    def add_bridge_route(self, source_peer: str, target_peer: str, 
                        allowed_networks: List[str]) -> bool:
        """Add bridge route between peers"""
        # source_peer is a name label; target_peer flows into iptables `-d` so must be
        # an IP/CIDR. allowed_networks flows into iptables `-s` so must all be CIDRs.
        if not isinstance(source_peer, str) or not re.match(r'^[a-zA-Z0-9_.-]{1,64}$', source_peer):
            logger.error(f"add_bridge_route: invalid source_peer {source_peer!r}")
            return {'success': False, 'error': f'invalid input: source_peer {source_peer!r}'}
        try:
            ipaddress.ip_network(target_peer, strict=False)
        except (ValueError, TypeError):
            logger.error(f"add_bridge_route: invalid target_peer {target_peer!r}")
            return {'success': False, 'error': f'invalid input: target_peer must be IP/CIDR, got {target_peer!r}'}
        if not isinstance(allowed_networks, list) or not allowed_networks:
            return {'success': False, 'error': 'invalid input: allowed_networks must be a non-empty list'}
        for n in allowed_networks:
            try:
                ipaddress.ip_network(n, strict=False)
            except (ValueError, TypeError):
                return {'success': False, 'error': f'invalid input: network {n!r}'}
        try:
            rules = self._load_rules()
            
            bridge_route = {
                'id': f"bridge_{len(rules['bridge_routes']) + 1}",
                'source_peer': source_peer,
                'target_peer': target_peer,
                'allowed_networks': allowed_networks,
                'enabled': True,
                'created_at': datetime.now().isoformat()
            }
            
            rules['bridge_routes'].append(bridge_route)
            self._save_rules(rules)
            
            # Apply bridge route
            self._apply_bridge_route(bridge_route)
            
            logger.info(f"Added bridge route {source_peer} -> {target_peer}")
            return True
            
        except Exception as e:
            logger.error(f"Failed to add bridge route: {e}")
            return False
    
    def add_split_route(self, network: str, exit_peer: str, 
                       fallback_peer: str = None) -> bool:
        """Add split routing rule"""
        # network flows into `ip route add <network>`; exit_peer flows into `via <exit_peer>`.
        try:
            ipaddress.ip_network(network, strict=False)
        except (ValueError, TypeError):
            logger.error(f"add_split_route: invalid network {network!r}")
            return {'success': False, 'error': f'invalid input: network {network!r}'}
        try:
            ipaddress.ip_address(exit_peer)
        except (ValueError, TypeError):
            logger.error(f"add_split_route: invalid exit_peer {exit_peer!r}")
            return {'success': False, 'error': f'invalid input: exit_peer must be an IP, got {exit_peer!r}'}
        if fallback_peer is not None:
            try:
                ipaddress.ip_address(fallback_peer)
            except (ValueError, TypeError):
                return {'success': False, 'error': f'invalid input: fallback_peer must be an IP, got {fallback_peer!r}'}
        try:
            rules = self._load_rules()
            
            split_route = {
                'id': f"split_{len(rules['split_routes']) + 1}",
                'network': network,
                'exit_peer': exit_peer,
                'fallback_peer': fallback_peer,
                'enabled': True,
                'created_at': datetime.now().isoformat()
            }
            
            rules['split_routes'].append(split_route)
            self._save_rules(rules)
            
            # Apply split route
            self._apply_split_route(split_route)
            
            logger.info(f"Added split route for {network}")
            return True
            
        except Exception as e:
            logger.error(f"Failed to add split route: {e}")
            return False
    
    def add_firewall_rule(self, rule_type: str, source: str, destination: str, action: str = 'ACCEPT', port: str = None, protocol: str = 'ALL', port_range: str = None) -> bool:
        """Add firewall rule with protocol and port range support."""
        # Validation
        if rule_type not in ['INPUT', 'OUTPUT', 'FORWARD']:
            logger.error(f"Invalid rule_type: {rule_type}")
            return False
        if not source or not self._validate_cidr(source):
            logger.error(f"Invalid source: {source}")
            return False
        if not destination or not self._validate_cidr(destination):
            logger.error(f"Invalid destination: {destination}")
            return False
        if action not in ['ACCEPT', 'DROP', 'REJECT']:
            logger.error(f"Invalid action: {action}")
            return False
        if protocol not in ['TCP', 'UDP', 'ICMP', 'ALL']:
            logger.error(f"Invalid protocol: {protocol}")
            return False
        if port is not None and port != '':
            try:
                port_num = int(port)
                if not (0 < port_num < 65536):
                    logger.error(f"Invalid port: {port}")
                    return False
            except Exception:
                logger.error(f"Invalid port: {port}")
                return False
        if port_range is not None and port_range != '':
            # Validate port range format (e.g., 1000-2000)
            if not re.match(r'^\d{1,5}-\d{1,5}$', port_range):
                logger.error(f"Invalid port_range: {port_range}")
                return False
        try:
            rules = self._load_rules()
            firewall_rule = {
                'id': f"fw_{len(rules['firewall_rules']) + 1}",
                'rule_type': rule_type,
                'source': source,
                'destination': destination,
                'action': action,
                'port': port,
                'protocol': protocol,
                'port_range': port_range,
                'enabled': True,
                'created_at': datetime.now().isoformat()
            }
            rules['firewall_rules'].append(firewall_rule)
            self._save_rules(rules)
            self._apply_firewall_rule(firewall_rule)
            logger.info(f"Added firewall rule {rule_type} {source} -> {destination} proto={protocol}")
            return True
        except Exception as e:
            logger.error(f"Failed to add firewall rule: {e}")
            return False
    
    def get_routing_status(self) -> Dict:
        """Get routing and gateway status"""
        try:
            rules = self._load_rules()
            
            # Get iptables status
            nat_rules_count = len([r for r in rules['nat_rules'] if r['enabled']])
            firewall_rules_count = len([r for r in rules['firewall_rules'] if r['enabled']])
            peer_routes_count = len([r for r in rules['peer_routes'].values() if r['enabled']])
            exit_nodes_count = len([r for r in rules['exit_nodes'] if r['enabled']])
            
            # Get routing table info
            routing_table = self._get_routing_table()
            
            return {
                'nat_rules_count': nat_rules_count,
                'firewall_rules_count': firewall_rules_count,
                'peer_routes_count': peer_routes_count,
                'exit_nodes_count': exit_nodes_count,
                'bridge_routes_count': len(rules['bridge_routes']),
                'split_routes_count': len(rules['split_routes']),
                'routing_table': routing_table,
                'active_rules': rules
            }
            
        except Exception as e:
            logger.error(f"Failed to get routing status: {e}")
            return {
                'nat_rules_count': 0,
                'firewall_rules_count': 0,
                'peer_routes_count': 0,
                'exit_nodes_count': 0,
                'bridge_routes_count': 0,
                'split_routes_count': 0,
                'routing_table': [],
                'active_rules': {}
            }
    
    def test_routing_connectivity(self, target_ip: str, via_peer: str = None) -> Dict:
        """Test routing connectivity by running ping/traceroute in cell-wireguard."""
        WG = 'cell-wireguard'

        def _exec(cmd):
            result = subprocess.run(
                ['docker', 'exec', WG] + cmd,
                capture_output=True, text=True, timeout=35
            )
            return {
                'success': result.returncode == 0,
                'output': result.stdout,
                'error': result.stderr,
            }

        results = {}
        try:
            results['ping'] = _exec(['ping', '-c', '4', '-W', '3', target_ip])
        except Exception as e:
            results['ping'] = {'success': False, 'output': '', 'error': str(e)}

        try:
            results['traceroute'] = _exec(['traceroute', '-m', '10', '-w', '2', target_ip])
        except Exception as e:
            results['traceroute'] = {'success': False, 'output': '', 'error': str(e)}

        if via_peer:
            try:
                results['peer_route'] = _exec(['ping', '-c', '3', '-W', '3', '-I', via_peer, target_ip])
            except Exception as e:
                results['peer_route'] = {'success': False, 'output': '', 'error': str(e)}

        return results
    
    def get_routing_logs(self, lines: int = 50) -> Dict:
        """Get routing and firewall logs"""
        try:
            logs = {}
            
            # Get iptables logs
            try:
                result = subprocess.run(['dmesg', '|', 'grep', 'iptables'], 
                                      capture_output=True, text=True, timeout=10)
                logs['iptables'] = result.stdout
            except Exception as e:
                logs['iptables'] = f"Error getting iptables logs: {e}"
            
            # Get routing logs
            try:
                result = subprocess.run(['dmesg', '|', 'grep', 'routing'], 
                                      capture_output=True, text=True, timeout=10)
                logs['routing'] = result.stdout
            except Exception as e:
                logs['routing'] = f"Error getting routing logs: {e}"
            
            # Get network interface logs
            try:
                result = subprocess.run(['ip', 'route', 'show'], 
                                      capture_output=True, text=True, timeout=10)
                logs['routes'] = result.stdout
            except Exception as e:
                logs['routes'] = f"Error getting route table: {e}"
            
            return logs
            
        except Exception as e:
            logger.error(f"Failed to get routing logs: {e}")
            return {'error': str(e)}
    
    def remove_firewall_rule(self, rule_id: str) -> bool:
        """Remove a stored firewall rule and delete it from iptables."""
        try:
            rules = self._load_rules()
            rule = next((r for r in rules['firewall_rules'] if r['id'] == rule_id), None)
            if not rule:
                return False
            rules['firewall_rules'] = [r for r in rules['firewall_rules'] if r['id'] != rule_id]
            self._save_rules(rules)
            try:
                cmd = ['iptables', '-D', rule['rule_type'],
                       '-s', rule['source'], '-d', rule['destination']]
                if rule.get('protocol') and rule['protocol'] != 'ALL':
                    cmd += ['-p', rule['protocol'].lower()]
                if rule.get('port'):
                    cmd += ['--dport', str(rule['port'])]
                if rule.get('port_range'):
                    cmd += ['--dport', rule['port_range'].replace('-', ':')]
                cmd += ['-j', rule['action']]
                subprocess.run(cmd, capture_output=True, timeout=10)
            except Exception as e:
                logger.warning(f"iptables -D failed (rule may already be gone): {e}")
            logger.info(f"Removed firewall rule {rule_id}")
            return True
        except Exception as e:
            logger.error(f"Failed to remove firewall rule: {e}")
            return False

    def get_live_iptables(self) -> dict:
        """Return live iptables rules from the WireGuard container."""
        out = {}
        for table in ('filter', 'nat'):
            try:
                r = subprocess.run(
                    ['docker', 'exec', 'cell-wireguard',
                     'iptables', '-t', table, '-L', '-n', '-v', '--line-numbers'],
                    capture_output=True, text=True, timeout=10
                )
                out[table] = r.stdout if r.returncode == 0 else r.stderr
            except Exception as e:
                out[table] = str(e)
        return out

    def get_nat_rules(self):
        """Return all NAT rules."""
        rules = self._load_rules()
        return rules.get('nat_rules', [])

    def get_peer_routes(self):
        """Return all peer routes as a list."""
        rules = self._load_rules()
        # peer_routes is a dict keyed by peer_name
        return list(rules.get('peer_routes', {}).values())

    def get_firewall_rules(self):
        """Return all firewall rules."""
        rules = self._load_rules()
        return rules.get('firewall_rules', [])
    
    def update_peer_ip(self, peer_name: str, new_ip: str) -> bool:
        """Update peer IP in all routes and re-apply them."""
        try:
            rules = self._load_rules()
            updated = False
            if 'peer_routes' in rules and peer_name in rules['peer_routes']:
                rules['peer_routes'][peer_name]['peer_ip'] = new_ip
                self._save_rules(rules)
                self._apply_peer_route(rules['peer_routes'][peer_name])
                updated = True
            # Optionally update exit_nodes, bridge_routes, split_routes if needed
            return updated
        except Exception as e:
            logger.error(f"Failed to update peer IP in routing: {e}")
            return False
    
    def get_status(self) -> Dict[str, Any]:
        """Get routing service status"""
        try:
            routing_status = self.get_routing_status()
            rules = self._load_rules()
            
            # Check if routing service is actually running by testing basic functionality
            is_running = self._is_routing_service_running()
            
            status = {
                'running': is_running,
                'status': 'online' if is_running else 'offline',
                'routing_status': routing_status,
                'nat_rules_count': len(rules.get('nat_rules', [])),
                'peer_routes_count': len(rules.get('peer_routes', {})),
                'exit_nodes_count': len(rules.get('exit_nodes', [])),
                'firewall_rules_count': len(rules.get('firewall_rules', [])),
                'timestamp': datetime.utcnow().isoformat()
            }
            
            return status
        except Exception as e:
            return self.handle_error(e, "get_status")

    def test_connectivity(self) -> Dict[str, Any]:
        """Test routing service connectivity"""
        try:
            # Test basic routing functionality
            routing_test = self._test_routing_functionality()
            
            # Test iptables access
            iptables_test = self._test_iptables_access()
            
            # Test network interfaces
            interfaces_test = self._test_network_interfaces()
            
            # Test routing table access
            routing_table_test = self._test_routing_table_access()
            
            results = {
                'routing_functionality': routing_test,
                'iptables_access': iptables_test,
                'network_interfaces': interfaces_test,
                'routing_table_access': routing_table_test,
                # iptables runs in cell-wireguard, not API container — exclude from success
                'success': routing_test.get('success', False),
                'timestamp': datetime.utcnow().isoformat()
            }
            
            return results
        except Exception as e:
            return self.handle_error(e, "test_connectivity")

    def _test_routing_functionality(self) -> Dict[str, Any]:
        """Test basic routing functionality"""
        try:
            # Test if we can read routing rules
            rules = self._load_rules()
            
            # Test if we can access routing status
            routing_status = self.get_routing_status()
            
            return {
                'success': True,
                'message': 'Routing functionality working',
                'rules_loaded': bool(rules),
                'status_accessible': bool(routing_status)
            }
        except Exception as e:
            return {
                'success': False,
                'message': f'Routing functionality test failed: {str(e)}',
                'error': str(e)
            }

    def _test_iptables_access(self) -> Dict[str, Any]:
        """Test iptables access"""
        try:
            # Test if we can list iptables rules
            result = subprocess.run(['iptables', '-L', '-n'], 
                                  capture_output=True, text=True, timeout=10)
            
            if result.returncode == 0:
                return {
                    'success': True,
                    'message': 'iptables access working',
                    'rules_count': len([line for line in result.stdout.split('\n') if line.strip()])
                }
            else:
                return {
                    'success': False,
                    'message': f'iptables access failed: {result.stderr}',
                    'error': result.stderr
                }
        except FileNotFoundError:
            # System tools not available (development environment)
            return {
                'success': True,
                'message': 'iptables not available (development mode)',
                'rules_count': 0
            }
        except Exception as e:
            return {
                'success': False,
                'message': f'iptables access test failed: {str(e)}',
                'error': str(e)
            }

    def _test_network_interfaces(self) -> Dict[str, Any]:
        """Test network interfaces access"""
        try:
            # Test if we can list network interfaces
            result = subprocess.run(['ip', 'link', 'show'], 
                                  capture_output=True, text=True, timeout=10)
            
            if result.returncode == 0:
                interfaces = [line.strip() for line in result.stdout.split('\n') if line.strip()]
                return {
                    'success': True,
                    'message': 'Network interfaces accessible',
                    'interfaces_count': len(interfaces)
                }
            else:
                return {
                    'success': False,
                    'message': f'Network interfaces access failed: {result.stderr}',
                    'error': result.stderr
                }
        except FileNotFoundError:
            # System tools not available (development environment)
            return {
                'success': True,
                'message': 'Network tools not available (development mode)',
                'interfaces_count': 0
            }
        except Exception as e:
            return {
                'success': False,
                'message': f'Network interfaces test failed: {str(e)}',
                'error': str(e)
            }

    def _test_routing_table_access(self) -> Dict[str, Any]:
        """Test routing table access"""
        try:
            # Test if we can read routing table
            result = subprocess.run(['ip', 'route', 'show'], 
                                  capture_output=True, text=True, timeout=10)
            
            if result.returncode == 0:
                routes = [line.strip() for line in result.stdout.split('\n') if line.strip()]
                return {
                    'success': True,
                    'message': 'Routing table accessible',
                    'routes_count': len(routes)
                }
            else:
                return {
                    'success': False,
                    'message': f'Routing table access failed: {result.stderr}',
                    'error': result.stderr
                }
        except FileNotFoundError:
            # System tools not available (development environment)
            return {
                'success': True,
                'message': 'Routing tools not available (development mode)',
                'routes_count': 0
            }
        except Exception as e:
            return {
                'success': False,
                'message': f'Routing table test failed: {str(e)}',
                'error': str(e)
            }
    
    def _load_rules(self) -> Dict:
        """Load routing rules from file"""
        try:
            with open(self.rules_file, 'r') as f:
                return json.load(f)
        except Exception as e:
            logger.error(f"Failed to load routing rules: {e}")
            return {}
    
    def _save_rules(self, rules: Dict):
        """Save routing rules to file"""
        try:
            with open(self.rules_file, 'w') as f:
                json.dump(rules, f, indent=2)
        except Exception as e:
            logger.error(f"Failed to save routing rules: {e}")
    
    def _apply_nat_rule(self, rule: Dict):
        """Apply NAT rule to iptables, supporting MASQUERADE, SNAT, DNAT, and port forwarding."""
        try:
            if rule.get('nat_type', 'MASQUERADE') == 'MASQUERADE' and rule['masquerade']:
                cmd = [
                    'iptables', '-t', 'nat', '-A', 'POSTROUTING',
                    '-s', rule['source_network'],
                    '-o', rule['target_interface'],
                    '-j', 'MASQUERADE'
                ]
                subprocess.run(cmd, check=True, timeout=10)
                logger.info(f"Applied MASQUERADE NAT rule: {rule['source_network']} -> {rule['target_interface']}")
            elif rule.get('nat_type') == 'DNAT' and rule['internal_ip']:
                # Port forwarding (DNAT)
                cmd = [
                    'iptables', '-t', 'nat', '-A', 'PREROUTING',
                    '-d', rule['source_network'],
                ]
                if rule.get('protocol') and rule['protocol'] != 'ALL':
                    cmd += ['-p', rule['protocol'].lower()]
                if rule.get('external_port'):
                    cmd += ['--dport', str(rule['external_port'])]
                cmd += ['-j', 'DNAT', '--to-destination', f"{rule['internal_ip']}{':' + str(rule['internal_port']) if rule.get('internal_port') else ''}"]
                subprocess.run(cmd, check=True, timeout=10)
                logger.info(f"Applied DNAT rule: {rule['source_network']}:{rule.get('external_port')} -> {rule['internal_ip']}:{rule.get('internal_port')}")
            elif rule.get('nat_type') == 'SNAT' and rule['internal_ip']:
                # 1:1 NAT (SNAT)
                cmd = [
                    'iptables', '-t', 'nat', '-A', 'POSTROUTING',
                    '-s', rule['internal_ip'],
                ]
                if rule.get('protocol') and rule['protocol'] != 'ALL':
                    cmd += ['-p', rule['protocol'].lower()]
                if rule.get('internal_port'):
                    cmd += ['--sport', str(rule['internal_port'])]
                cmd += ['-j', 'SNAT', '--to-source', rule['source_network']]
                subprocess.run(cmd, check=True, timeout=10)
                logger.info(f"Applied SNAT rule: {rule['internal_ip']} -> {rule['source_network']}")
        except Exception as e:
            logger.error(f"Failed to apply NAT rule: {e}")
    
    def _remove_nat_rule(self, rule_id: str):
        """Remove NAT rule from iptables by rule_id comment tag."""
        try:
            # Use -D with the comment tag to remove the specific rule rather than
            # flushing the entire POSTROUTING chain (which would wipe WireGuard MASQUERADE).
            cmd = ['iptables', '-t', 'nat', '-D', 'POSTROUTING',
                   '-m', 'comment', '--comment', rule_id, '-j', 'MASQUERADE']
            result = subprocess.run(cmd, timeout=10)
            if result.returncode != 0:
                # Rule may not exist — not an error
                logger.debug(f"NAT rule {rule_id} not found (already removed?)")
            else:
                logger.info(f"Removed NAT rule: {rule_id}")
        except Exception as e:
            logger.error(f"Failed to remove NAT rule: {e}")
    
    def _apply_peer_route(self, route: Dict):
        """Apply peer routing rule"""
        try:
            # Add route for peer networks
            for network in route['allowed_networks']:
                cmd = [
                    'ip', 'route', 'add', network,
                    'via', route['peer_ip'],
                    'dev', 'wg0'
                ]
                subprocess.run(cmd, check=True, timeout=10)
            
            logger.info(f"Applied peer route for {route['peer_name']}")
            
        except Exception as e:
            logger.error(f"Failed to apply peer route: {e}")
    
    def _remove_peer_route(self, peer_name: str):
        """Remove peer routing rule"""
        try:
            # Remove routes for this peer
            cmd = ['ip', 'route', 'del', 'via', peer_name, 'dev', 'wg0']
            subprocess.run(cmd, check=True, timeout=10)
            
            logger.info(f"Removed peer route for {peer_name}")
            
        except Exception as e:
            logger.error(f"Failed to remove peer route: {e}")
    
    def _apply_exit_node(self, exit_node: Dict):
        """Apply exit node configuration"""
        try:
            # Add default route through exit node
            cmd = [
                'ip', 'route', 'add', 'default',
                'via', exit_node['peer_ip'],
                'dev', 'wg0'
            ]
            subprocess.run(cmd, check=True, timeout=10)
            
            logger.info(f"Applied exit node {exit_node['peer_name']}")
            
        except Exception as e:
            logger.error(f"Failed to apply exit node: {e}")
    
    def _apply_bridge_route(self, route: Dict):
        """Apply bridge routing rule"""
        try:
            # Add forwarding rules for bridge
            for network in route['allowed_networks']:
                cmd = [
                    'iptables', '-A', 'FORWARD',
                    '-s', network,
                    '-d', route['target_peer'],
                    '-j', 'ACCEPT'
                ]
                subprocess.run(cmd, check=True, timeout=10)
            
            logger.info(f"Applied bridge route {route['source_peer']} -> {route['target_peer']}")
            
        except Exception as e:
            logger.error(f"Failed to apply bridge route: {e}")
    
    def _apply_split_route(self, route: Dict):
        """Apply split routing rule"""
        try:
            # Add specific route for network
            cmd = [
                'ip', 'route', 'add', route['network'],
                'via', route['exit_peer'],
                'dev', 'wg0'
            ]
            subprocess.run(cmd, check=True, timeout=10)
            
            logger.info(f"Applied split route for {route['network']}")
            
        except Exception as e:
            logger.error(f"Failed to apply split route: {e}")
    
    def _apply_firewall_rule(self, rule: Dict):
        """Apply firewall rule with protocol and port range support."""
        try:
            cmd = [
                'iptables', '-A', rule['rule_type'],
                '-s', rule['source'],
                '-d', rule['destination']
            ]
            if rule.get('protocol') and rule['protocol'] != 'ALL':
                cmd += ['-p', rule['protocol'].lower()]
            if rule.get('port'):
                cmd += ['--dport', str(rule['port'])]
            if rule.get('port_range'):
                cmd += ['--dport', rule['port_range'].replace('-', ':')]
            cmd += ['-j', rule['action']]
            subprocess.run(cmd, check=True, timeout=10)
            logger.info(f"Applied firewall rule {rule['rule_type']} proto={rule.get('protocol')} port={rule.get('port') or rule.get('port_range')}")
        except Exception as e:
            logger.error(f"Failed to apply firewall rule: {e}")
    
    def _get_routing_table(self) -> List[Dict]:
        """Get host routing table from /proc/1/net/route (host PID namespace)."""
        try:
            return self._parse_proc_net_route('/proc/1/net/route')
        except Exception:
            pass
        # Fallback: WireGuard container routing table
        try:
            result = subprocess.run(
                ['docker', 'exec', 'cell-wireguard', 'ip', 'route', 'show'],
                capture_output=True, text=True, timeout=10,
            )
            if result.returncode == 0:
                routes = []
                for line in result.stdout.strip().split('\n'):
                    if line.strip():
                        routes.append({'route': line.strip(), 'parsed': self._parse_route(line.strip())})
                return routes
        except Exception as e:
            logger.error(f"Failed to get routing table: {e}")
        return []

    def _parse_proc_net_route(self, path: str) -> List[Dict]:
        """Parse /proc/net/route hex table into human-readable routes."""
        import socket, struct
        routes = []
        with open(path) as f:
            lines = f.readlines()[1:]  # skip header
        for line in lines:
            parts = line.strip().split()
            if len(parts) < 8:
                continue
            iface, dest_hex, gw_hex, mask_hex = parts[0], parts[1], parts[2], parts[7]

            def hex_to_ip(h):
                return socket.inet_ntoa(struct.pack('<I', int(h, 16)))

            dest = hex_to_ip(dest_hex)
            gw = hex_to_ip(gw_hex)
            mask = hex_to_ip(mask_hex)
            prefix = bin(struct.unpack('>I', socket.inet_aton(mask))[0]).count('1')

            if dest == '0.0.0.0' and mask == '0.0.0.0':
                dest_str = 'default'
                route_str = f'default via {gw} dev {iface}'
            else:
                dest_str = f'{dest}/{prefix}'
                route_str = f'{dest}/{prefix} dev {iface}' + (f' via {gw}' if gw != '0.0.0.0' else '')

            routes.append({
                'route': route_str,
                'parsed': {'destination': dest_str, 'via': gw if gw != '0.0.0.0' else '', 'dev': iface, 'metric': ''},
            })
        return routes
    
    def _parse_route(self, route_line: str) -> Dict:
        """Parse route line into components"""
        try:
            # Simple route parsing - can be enhanced
            parts = route_line.split()
            parsed = {
                'destination': parts[0] if parts else '',
                'via': '',
                'dev': '',
                'metric': ''
            }
            
            for i, part in enumerate(parts):
                if part == 'via' and i + 1 < len(parts):
                    parsed['via'] = parts[i + 1]
                elif part == 'dev' and i + 1 < len(parts):
                    parsed['dev'] = parts[i + 1]
                elif part == 'metric' and i + 1 < len(parts):
                    parsed['metric'] = parts[i + 1]
            
            return parsed
            
        except Exception as e:
            logger.error(f"Failed to parse route: {e}")
            return {'destination': route_line, 'via': '', 'dev': '', 'metric': ''}
    
    def _is_routing_service_running(self) -> bool:
        """Check if routing service is actually running"""
        # Use internal state tracking instead of system tool checks
        return self._service_running
    
    def start(self) -> bool:
        """Start routing service"""
        try:
            # Set internal state to running
            self._service_running = True
            self._save_service_state()
            
            # Try to enable IP forwarding (may fail in Docker without privileges)
            try:
                subprocess.run(['sysctl', '-w', 'net.ipv4.ip_forward=1'], 
                              check=True, timeout=10)
            except (subprocess.CalledProcessError, FileNotFoundError) as e:
                logger.warning(f"Could not enable IP forwarding: {e}")
                # Continue anyway - service is considered started
            
            # Load existing rules
            rules = self._load_rules()
            
            # Apply all enabled rules (may fail in Docker without privileges)
            try:
                for rule in rules.get('nat_rules', []):
                    if rule.get('enabled', True):
                        self._apply_nat_rule(rule)
                
                for rule in rules.get('firewall_rules', []):
                    if rule.get('enabled', True):
                        self._apply_firewall_rule(rule)
                
                for route in rules.get('peer_routes', {}).values():
                    if route.get('enabled', True):
                        self._apply_peer_route(route)
                
                for exit_node in rules.get('exit_nodes', []):
                    if exit_node.get('enabled', True):
                        self._apply_exit_node(exit_node)
            except Exception as e:
                logger.warning(f"Could not apply routing rules: {e}")
                # Continue anyway - service is considered started
            
            logger.info("Routing service started successfully")
            return True
            
        except Exception as e:
            logger.error(f"Failed to start routing service: {e}")
            self._service_running = False
            self._save_service_state()
            return False
    
    def stop(self) -> bool:
        """Stop routing service (state only — iptables rules are NOT flushed).

        Flushing iptables here would destroy WireGuard MASQUERADE and all peer
        FORWARD rules applied by firewall_manager.  Individual rule removal is
        handled by remove_nat_rule() / remove_firewall_rule().
        """
        try:
            self._service_running = False
            self._save_service_state()
            logger.info("Routing service stopped (state only; iptables untouched)")
            return True
        except Exception as e:
            logger.error(f"Failed to stop routing service: {e}")
            # Even if system commands fail, we consider the service stopped
            self._service_running = False
            self._save_service_state()
            return True  # Return True because the state is now stopped
    
    def restart(self) -> bool:
        """Restart routing service"""
        try:
            self.stop()
            time.sleep(1)  # Brief pause
            return self.start()
        except Exception as e:
            logger.error(f"Failed to restart routing service: {e}")
            return False