/**
 * Author: David Valera Melendez
 * Email: david@valera-melendez.de
 * Created: March 2025
 */
import { Injectable, CanActivate, ExecutionContext } from '@nestjs/common';
import { Reflector } from '@nestjs/core';
import { Role } from '../constants/role.enum';

/**
 * RolesGuard checks if the user has the required roles for a route.
 * Supports enums, strings, and can be extended for role hierarchies.
 */
@Injectable()
export class RolesGuard implements CanActivate {
  constructor(private reflector: Reflector) {}

  canActivate(context: ExecutionContext): boolean {
    const requiredRoles = this.reflector.getAllAndOverride<(Role | string)[]>('roles', [
      context.getHandler(),
      context.getClass(),
    ]);
    if (!requiredRoles || requiredRoles.length === 0) {
      return true;
    }
    const { user } = context.switchToHttp().getRequest();
    if (!user || !user.roles) return false;
    // Support for enums and strings, and future role hierarchies
    return user.roles.some((userRole: string) =>
      requiredRoles.includes(userRole as Role)
    );
  }
}