#!/usr/bin/env python3
"""
WebDAV Server CLI Management Tool
Command-line interface for managing users, permissions, and server configuration
"""

import sys
import asyncio
import argparse
from pathlib import Path
from getpass import getpass
from datetime import datetime
import sqlite3

# Import from main application
from main import Database, Config


class WebDAVCLI:
    """Command-line interface for WebDAV server management"""
    
    def __init__(self):
        self.db = Database(Config.DB_PATH)
    
    # ========================================================================
    # User Management
    # ========================================================================
    
    async def create_user(self, username: str, password: str = None, 
                         email: str = None, role: str = 'user'):
        """Create a new user"""
        if not password:
            password = getpass(f"Enter password for {username}: ")
            password_confirm = getpass("Confirm password: ")
            
            if password != password_confirm:
                print("❌ Passwords do not match!")
                return False
        
        if len(password) < Config.PASSWORD_MIN_LENGTH:
            print(f"❌ Password must be at least {Config.PASSWORD_MIN_LENGTH} characters!")
            return False
        
        try:
            user_id = await self.db.create_user(username, password, email, role)
            print(f"✅ User created successfully!")
            print(f"   ID: {user_id}")
            print(f"   Username: {username}")
            print(f"   Email: {email or 'N/A'}")
            print(f"   Role: {role}")
            return True
        except Exception as e:
            print(f"❌ Error creating user: {e}")
            return False
    
    async def list_users(self):
        """List all users"""
        conn = self.db.get_connection()
        cursor = conn.cursor()
        cursor.execute('SELECT id, username, email, role, is_active, created_at, last_login FROM users')
        users = cursor.fetchall()
        conn.close()
        
        if not users:
            print("No users found.")
            return
        
        print(f"\n{'ID':<5} {'Username':<20} {'Email':<30} {'Role':<10} {'Active':<8} {'Created':<20}")
        print("=" * 100)
        
        for user in users:
            active = "✓" if user['is_active'] else "✗"
            created = user['created_at'][:19] if user['created_at'] else 'N/A'
            email = user['email'] or 'N/A'
            
            print(f"{user['id']:<5} {user['username']:<20} {email:<30} {user['role']:<10} {active:<8} {created:<20}")
    
    async def delete_user(self, username: str, force: bool = False):
        """Delete a user"""
        if not force:
            confirm = input(f"Are you sure you want to delete user '{username}'? (yes/no): ")
            if confirm.lower() != 'yes':
                print("Deletion cancelled.")
                return False
        
        try:
            conn = self.db.get_connection()
            cursor = conn.cursor()
            cursor.execute('DELETE FROM users WHERE username = ?', (username,))
            deleted = cursor.rowcount > 0
            conn.commit()
            conn.close()
            
            if deleted:
                # Remove user directory
                user_dir = Path(Config.WEBDAV_ROOT) / 'users' / username
                if user_dir.exists():
                    import shutil
                    shutil.rmtree(user_dir)
                
                print(f"✅ User '{username}' deleted successfully!")
                return True
            else:
                print(f"❌ User '{username}' not found!")
                return False
        
        except Exception as e:
            print(f"❌ Error deleting user: {e}")
            return False
    
    async def change_password(self, username: str, new_password: str = None):
        """Change user password"""
        if not new_password:
            new_password = getpass(f"Enter new password for {username}: ")
            password_confirm = getpass("Confirm new password: ")
            
            if new_password != password_confirm:
                print("❌ Passwords do not match!")
                return False
        
        if len(new_password) < Config.PASSWORD_MIN_LENGTH:
            print(f"❌ Password must be at least {Config.PASSWORD_MIN_LENGTH} characters!")
            return False
        
        try:
            import hashlib
            import secrets
            
            salt = secrets.token_hex(16)
            password_hash = hashlib.pbkdf2_hmac('sha256', new_password.encode(), salt.encode(), 100000).hex()
            
            conn = self.db.get_connection()
            cursor = conn.cursor()
            cursor.execute('UPDATE users SET password_hash = ?, salt = ? WHERE username = ?',
                          (password_hash, salt, username))
            updated = cursor.rowcount > 0
            conn.commit()
            conn.close()
            
            if updated:
                print(f"✅ Password changed successfully for user '{username}'!")
                return True
            else:
                print(f"❌ User '{username}' not found!")
                return False
        
        except Exception as e:
            print(f"❌ Error changing password: {e}")
            return False
    
    async def activate_user(self, username: str, active: bool = True):
        """Activate or deactivate a user"""
        try:
            conn = self.db.get_connection()
            cursor = conn.cursor()
            cursor.execute('UPDATE users SET is_active = ? WHERE username = ?',
                          (1 if active else 0, username))
            updated = cursor.rowcount > 0
            conn.commit()
            conn.close()
            
            if updated:
                status = "activated" if active else "deactivated"
                print(f"✅ User '{username}' {status} successfully!")
                return True
            else:
                print(f"❌ User '{username}' not found!")
                return False
        
        except Exception as e:
            print(f"❌ Error updating user: {e}")
            return False
    
    # ========================================================================
    # Lock Management
    # ========================================================================
    
    async def list_locks(self):
        """List all active locks"""
        conn = self.db.get_connection()
        cursor = conn.cursor()
        cursor.execute('''
            SELECT l.lock_token, l.resource_path, l.lock_type, l.lock_scope,
                   l.created_at, l.timeout_seconds, u.username
            FROM locks l
            LEFT JOIN users u ON l.user_id = u.id
            WHERE datetime(l.created_at, '+' || l.timeout_seconds || ' seconds') > datetime('now')
        ''')
        locks = cursor.fetchall()
        conn.close()
        
        if not locks:
            print("No active locks found.")
            return
        
        print(f"\n{'Resource':<40} {'Type':<10} {'Scope':<12} {'Owner':<15} {'Created':<20}")
        print("=" * 100)
        
        for lock in locks:
            created = lock['created_at'][:19] if lock['created_at'] else 'N/A'
            owner = lock['username'] or 'Unknown'
            
            print(f"{lock['resource_path']:<40} {lock['lock_type']:<10} {lock['lock_scope']:<12} {owner:<15} {created:<20}")
    
    async def remove_lock(self, resource_path: str):
        """Remove a lock from a resource"""
        try:
            conn = self.db.get_connection()
            cursor = conn.cursor()
            cursor.execute('DELETE FROM locks WHERE resource_path = ?', (resource_path,))
            deleted = cursor.rowcount > 0
            conn.commit()
            conn.close()
            
            if deleted:
                print(f"✅ Lock removed from '{resource_path}'!")
                return True
            else:
                print(f"❌ No lock found on '{resource_path}'!")
                return False
        
        except Exception as e:
            print(f"❌ Error removing lock: {e}")
            return False
    
    # ========================================================================
    # Statistics and Info
    # ========================================================================
    
    async def show_stats(self):
        """Show server statistics"""
        conn = self.db.get_connection()
        cursor = conn.cursor()
        
        # User statistics
        cursor.execute('SELECT COUNT(*) as total, SUM(is_active) as active FROM users')
        user_stats = cursor.fetchone()
        
        # Lock statistics
        cursor.execute('''
            SELECT COUNT(*) as total FROM locks
            WHERE datetime(created_at, '+' || timeout_seconds || ' seconds') > datetime('now')
        ''')
        lock_stats = cursor.fetchone()
        
        # Session statistics
        cursor.execute('''
            SELECT COUNT(*) as total FROM sessions
            WHERE datetime(expires_at) > datetime('now')
        ''')
        session_stats = cursor.fetchone()
        
        # Properties statistics
        cursor.execute('SELECT COUNT(*) as total FROM properties')
        prop_stats = cursor.fetchone()
        
        conn.close()
        
        # Storage statistics
        webdav_root = Path(Config.WEBDAV_ROOT)
        if webdav_root.exists():
            total_size = sum(f.stat().st_size for f in webdav_root.rglob('*') if f.is_file())
            total_files = sum(1 for f in webdav_root.rglob('*') if f.is_file())
        else:
            total_size = 0
            total_files = 0
        
        print("\n" + "=" * 60)
        print("WebDAV Server Statistics")
        print("=" * 60)
        print(f"\n📊 Users:")
        print(f"   Total: {user_stats['total']}")
        print(f"   Active: {user_stats['active']}")
        print(f"   Inactive: {user_stats['total'] - user_stats['active']}")
        
        print(f"\n🔒 Locks:")
        print(f"   Active: {lock_stats['total']}")
        
        print(f"\n🔑 Sessions:")
        print(f"   Active: {session_stats['total']}")
        
        print(f"\n📝 Properties:")
        print(f"   Total: {prop_stats['total']}")
        
        print(f"\n💾 Storage:")
        print(f"   Total files: {total_files:,}")
        print(f"   Total size: {total_size:,} bytes ({total_size / 1024 / 1024:.2f} MB)")
        
        print("\n" + "=" * 60)
    
    async def clear_cache(self):
        """Clear authentication cache"""
        print("⚠️  This requires the server to be running with cache management enabled.")
        print("Cache statistics are only available via server admin interface.")
        print("\nTo clear cache:")
        print("1. Stop the server")
        print("2. Restart the server (cache is in-memory only)")
        print("\nOr use the admin API if enabled:")
        print("  curl -X POST http://localhost:8080/admin/cache/clear")
    
    # ========================================================================
    # Database Management
    # ========================================================================
    
    async def backup_database(self, output_path: str = None):
        """Backup the database"""
        if not output_path:
            timestamp = datetime.now().strftime('%Y%m%d_%H%M%S')
            output_path = f"./backups/webdav_backup_{timestamp}.db"
        
        try:
            import shutil
            Path(output_path).parent.mkdir(parents=True, exist_ok=True)
            shutil.copy2(Config.DB_PATH, output_path)
            print(f"✅ Database backed up to: {output_path}")
            return True
        except Exception as e:
            print(f"❌ Error backing up database: {e}")
            return False
    
    async def restore_database(self, backup_path: str):
        """Restore database from backup"""
        if not Path(backup_path).exists():
            print(f"❌ Backup file not found: {backup_path}")
            return False
        
        confirm = input("⚠️  This will overwrite the current database. Continue? (yes/no): ")
        if confirm.lower() != 'yes':
            print("Restore cancelled.")
            return False
        
        try:
            import shutil
            shutil.copy2(backup_path, Config.DB_PATH)
            print(f"✅ Database restored from: {backup_path}")
            return True
        except Exception as e:
            print(f"❌ Error restoring database: {e}")
            return False


# ============================================================================
# CLI Command Handlers
# ============================================================================

async def main():
    """Main CLI entry point"""
    parser = argparse.ArgumentParser(
        description='WebDAV Server Management CLI',
        formatter_class=argparse.RawDescriptionHelpFormatter,
        epilog="""
Examples:
  %(prog)s user create john --email john@example.com
  %(prog)s user list
  %(prog)s user delete john
  %(prog)s user password john
  %(prog)s lock list
  %(prog)s stats
  %(prog)s backup
        """
    )
    
    subparsers = parser.add_subparsers(dest='command', help='Available commands')
    
    # User commands
    user_parser = subparsers.add_parser('user', help='User management')
    user_subparsers = user_parser.add_subparsers(dest='user_command')
    
    # Create user
    create_parser = user_subparsers.add_parser('create', help='Create a new user')
    create_parser.add_argument('username', help='Username')
    create_parser.add_argument('--password', help='Password (will prompt if not provided)')
    create_parser.add_argument('--email', help='Email address')
    create_parser.add_argument('--role', default='user', choices=['user', 'admin'], help='User role')
    
    # List users
    user_subparsers.add_parser('list', help='List all users')
    
    # Delete user
    delete_parser = user_subparsers.add_parser('delete', help='Delete a user')
    delete_parser.add_argument('username', help='Username to delete')
    delete_parser.add_argument('--force', action='store_true', help='Skip confirmation')
    
    # Change password
    password_parser = user_subparsers.add_parser('password', help='Change user password')
    password_parser.add_argument('username', help='Username')
    password_parser.add_argument('--new-password', help='New password (will prompt if not provided)')
    
    # Activate/deactivate user
    activate_parser = user_subparsers.add_parser('activate', help='Activate a user')
    activate_parser.add_argument('username', help='Username')
    
    deactivate_parser = user_subparsers.add_parser('deactivate', help='Deactivate a user')
    deactivate_parser.add_argument('username', help='Username')
    
    # Lock commands
    lock_parser = subparsers.add_parser('lock', help='Lock management')
    lock_subparsers = lock_parser.add_subparsers(dest='lock_command')
    
    lock_subparsers.add_parser('list', help='List all active locks')
    
    remove_parser = lock_subparsers.add_parser('remove', help='Remove a lock')
    remove_parser.add_argument('resource', help='Resource path')
    
    # Statistics
    subparsers.add_parser('stats', help='Show server statistics')
    
    # Backup
    backup_parser = subparsers.add_parser('backup', help='Backup database')
    backup_parser.add_argument('--output', help='Output path for backup')
    
    # Restore
    restore_parser = subparsers.add_parser('restore', help='Restore database from backup')
    restore_parser.add_argument('backup', help='Path to backup file')
    
    args = parser.parse_args()
    
    if not args.command:
        parser.print_help()
        return
    
    cli = WebDAVCLI()
    
    # Execute command
    try:
        if args.command == 'user':
            if args.user_command == 'create':
                await cli.create_user(args.username, args.password, args.email, args.role)
            elif args.user_command == 'list':
                await cli.list_users()
            elif args.user_command == 'delete':
                await cli.delete_user(args.username, args.force)
            elif args.user_command == 'password':
                await cli.change_password(args.username, getattr(args, 'new_password', None))
            elif args.user_command == 'activate':
                await cli.activate_user(args.username, True)
            elif args.user_command == 'deactivate':
                await cli.activate_user(args.username, False)
            else:
                user_parser.print_help()
        
        elif args.command == 'lock':
            if args.lock_command == 'list':
                await cli.list_locks()
            elif args.lock_command == 'remove':
                await cli.remove_lock(args.resource)
            else:
                lock_parser.print_help()
        
        elif args.command == 'stats':
            await cli.show_stats()
        
        elif args.command == 'backup':
            await cli.backup_database(args.output)
        
        elif args.command == 'restore':
            await cli.restore_database(args.backup)
    
    except KeyboardInterrupt:
        print("\n\nOperation cancelled.")
        sys.exit(1)
    except Exception as e:
        print(f"\n❌ Error: {e}")
        sys.exit(1)


if __name__ == '__main__':
    asyncio.run(main())