"""
Admin routes and functionality for Outline VPN
"""
import os
import json
import psutil
import zipfile
from datetime import datetime
from flask import jsonify, request, send_file, flash, redirect, url_for
from flask_login import login_required, current_user
from . import app
from .models import User, UserRole, SystemHealth, AuditLog, Alert
from .services import backup_service, monitoring_service

def admin_required(f):
    """Decorator to require admin role for routes"""
    @wraps(f)
    def decorated_function(*args, **kwargs):
        if not current_user.is_authenticated or current_user.role != UserRole.ADMIN:
            flash('You need administrator privileges to access this page.')
            return redirect(url_for('dashboard'))
        return f(*args, **kwargs)
    return decorated_function

@app.route('/admin')
@login_required
@admin_required
def admin_dashboard():
    """Admin dashboard view"""
    system_health = monitoring_service.get_system_health()
    active_alerts = Alert.query.filter_by(status='active').order_by(Alert.created_at.desc()).all()
    audit_logs = AuditLog.query.order_by(AuditLog.timestamp.desc()).limit(50).all()
    
    return render_template('admin.html',
                         system_health=system_health,
                         active_alerts=active_alerts,
                         audit_logs=audit_logs)

@app.route('/api/system-health')
@login_required
@admin_required
def get_system_health():
    """Get real-time system health metrics"""
    return jsonify(monitoring_service.get_system_health())

@app.route('/api/update-server-config', methods=['POST'])
@login_required
@admin_required
def update_server_config():
    """Update server configuration"""
    try:
        config = request.get_json()
        backup_service.backup_config('pre_update')  # Create backup before updating
        
        # Update configuration
        current_config = ServerConfig.query.first()
        for key, value in config.items():
            setattr(current_config, key, value)
        
        db.session.commit()
        
        # Log the change
        AuditLog.create(
            user_id=current_user.id,
            action='update_config',
            details='Server configuration updated'
        )
        
        # Restart required services
        monitoring_service.restart_services()
        
        return jsonify({'status': 'success'})
    except Exception as e:
        return jsonify({'status': 'error', 'message': str(e)}), 500

@app.route('/api/create-backup')
@login_required
@admin_required
def create_backup():
    """Create a backup of server configuration"""
    try:
        include_user_data = request.args.get('include_user_data', 'false') == 'true'
        backup_path = backup_service.create_backup(include_user_data)
        
        # Log the backup creation
        AuditLog.create(
            user_id=current_user.id,
            action='create_backup',
            details=f'Backup created: {os.path.basename(backup_path)}'
        )
        
        return send_file(
            backup_path,
            as_attachment=True,
            download_name=f'outline_backup_{datetime.now().strftime("%Y%m%d_%H%M%S")}.zip'
        )
    except Exception as e:
        flash(f'Error creating backup: {str(e)}', 'error')
        return redirect(url_for('admin_dashboard'))

@app.route('/api/restore-config', methods=['POST'])
@login_required
@admin_required
def restore_config():
    """Restore server configuration from backup"""
    try:
        if 'backup_file' not in request.files:
            flash('No backup file provided', 'error')
            return redirect(url_for('admin_dashboard'))
        
        backup_file = request.files['backup_file']
        if backup_file.filename == '':
            flash('No backup file selected', 'error')
            return redirect(url_for('admin_dashboard'))
        
        # Create backup of current configuration
        backup_service.backup_config('pre_restore')
        
        # Restore from backup
        backup_service.restore_from_backup(backup_file)
        
        # Log the restore
        AuditLog.create(
            user_id=current_user.id,
            action='restore_config',
            details=f'Configuration restored from {backup_file.filename}'
        )
        
        flash('Configuration restored successfully', 'success')
        return redirect(url_for('admin_dashboard'))
    except Exception as e:
        flash(f'Error restoring configuration: {str(e)}', 'error')
        return redirect(url_for('admin_dashboard'))

@app.route('/api/export-audit-log')
@login_required
@admin_required
def export_audit_log():
    """Export audit log in specified format"""
    format = request.args.get('format', 'csv')
    logs = AuditLog.query.order_by(AuditLog.timestamp.desc()).all()
    
    if format == 'csv':
        output = io.StringIO()
        writer = csv.writer(output)
        writer.writerow(['Timestamp', 'User', 'Action', 'Details'])
        for log in logs:
            writer.writerow([
                log.timestamp.strftime('%Y-%m-%d %H:%M:%S'),
                log.user.username,
                log.action,
                log.details
            ])
        
        return Response(
            output.getvalue(),
            mimetype='text/csv',
            headers={'Content-Disposition': 'attachment; filename=audit_log.csv'}
        )
    elif format == 'json':
        return jsonify([{
            'timestamp': log.timestamp.strftime('%Y-%m-%d %H:%M:%S'),
            'user': log.user.username,
            'action': log.action,
            'details': log.details
        } for log in logs])