package org.apache.helix.ui.resource;

/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you 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
 *
 *   http://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.
 */

import org.apache.helix.model.ExternalView;
import org.apache.helix.model.IdealState;
import org.apache.helix.tools.ClusterSetup;
import org.apache.helix.ui.api.ClusterSpec;
import org.apache.helix.ui.api.D3ResourceCoCentricCircle;
import org.apache.helix.ui.api.InstanceSpec;
import org.apache.helix.ui.api.ResourceStateSpec;
import org.apache.helix.ui.util.ClientCache;
import org.apache.helix.ui.util.DataCache;

import javax.ws.rs.*;
import javax.ws.rs.core.MediaType;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

@Path("/visualizer")
public class VisualizerResource {
  private final ClientCache clientCache;
  private final DataCache dataCache;

  public VisualizerResource(ClientCache clientCache, DataCache dataCache) {
    this.clientCache = clientCache;
    this.dataCache = dataCache;
  }

  @GET
  @Path("/{zkAddress}/{clusterName}/{resourceName}")
  @Produces(MediaType.APPLICATION_JSON)
  public D3ResourceCoCentricCircle getD3HelixResource(
          @PathParam("zkAddress") String zkAddress,
          @PathParam("clusterName") String clusterName,
          @PathParam("resourceName") String resourceName) throws Exception {
    ClusterSetup clusterSetup = clientCache.get(zkAddress).getClusterSetup();

    IdealState idealState
            = clusterSetup.getClusterManagementTool().getResourceIdealState(clusterName, resourceName);
    ExternalView externalView
            = clusterSetup.getClusterManagementTool().getResourceExternalView(clusterName, resourceName);
    if (idealState == null) {
      throw new NotFoundException("No resource ideal state for " + resourceName);
    }

    // Instances in active cluster
    List<InstanceSpec> instanceSpecs = dataCache.getInstanceCache().get(new ClusterSpec(zkAddress, clusterName));
    Map<String, InstanceSpec> instanceSpecMap = new HashMap<String, InstanceSpec>(instanceSpecs.size());
    for (InstanceSpec instanceSpec : instanceSpecs) {
      instanceSpecMap.put(instanceSpec.getInstanceName(), instanceSpec);
    }

    return D3ResourceCoCentricCircle.fromResourceStateSpec(
            new ResourceStateSpec(resourceName, idealState, externalView, instanceSpecMap));
  }
}