<%#
 Copyright 2013-2021 the original author or authors from the JHipster project.

 This file is part of the JHipster project, see https://www.jhipster.tech/
 for more information.

 Licensed under the Apache License, Version 2.0 (the "License");
 you may not use this file except in compliance with the License.
 You may obtain a copy of the License at

      https://www.apache.org/licenses/LICENSE-2.0

 Unless required by applicable law or agreed to in writing, software
 distributed under the License is distributed on an "AS IS" BASIS,
 WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 See the License for the specific language governing permissions and
 limitations under the License.
-%>
package <%= packageName %>.web.rest;

import <%= packageName %>.web.rest.vm.RouteVM;

import java.util.ArrayList;
import java.util.List;

import org.springframework.cloud.client.discovery.DiscoveryClient;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.cloud.gateway.route.Route;
import org.springframework.cloud.gateway.route.RouteLocator;
import reactor.core.publisher.Flux;
import org.springframework.http.*;
import org.springframework.security.access.annotation.Secured;
import <%= packageName %>.security.AuthoritiesConstants;
import org.springframework.web.bind.annotation.*;

/**
 * REST controller for managing Gateway configuration.
 */
@RestController
@RequestMapping("/api/gateway")
public class GatewayResource {

    private final RouteLocator routeLocator;

    private final DiscoveryClient discoveryClient;

    @Value("${spring.application.name}")
    private String appName;

    public GatewayResource(RouteLocator routeLocator, DiscoveryClient discoveryClient) {
        this.routeLocator = routeLocator;
        this.discoveryClient = discoveryClient;
    }

    /**
     * {@code GET  /routes} : get the active routes.
     *
     * @return the {@link ResponseEntity} with status {@code 200 (OK)} and with body the list of routes.
     */
    @GetMapping("/routes")
    @Secured(AuthoritiesConstants.ADMIN)
    public ResponseEntity<List<RouteVM>> activeRoutes() {
        Flux<Route> routes = routeLocator.getRoutes();
        List<RouteVM> routeVMs = new ArrayList<>();
        routes.subscribe(route -> {
            RouteVM routeVM = new RouteVM();
            // Manipulate strings to make Gateway routes look like Zuul's
            String predicate = route.getPredicate().toString();
            String path = predicate.substring(predicate.indexOf("[") + 1, predicate.indexOf("]"));
            routeVM.setPath(path);
            String serviceId = route.getId().substring(route.getId().indexOf("_") + 1).toLowerCase();
            routeVM.setServiceId(serviceId);
            // Exclude gateway app from routes
            if (!serviceId.equalsIgnoreCase(appName)) {
                routeVM.setServiceInstances(discoveryClient.getInstances(serviceId));
                routeVMs.add(routeVM);
            }
        });
        return ResponseEntity.ok(routeVMs);
    }
}
