/**
 * 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.
 */

var App = require('app');

App.DataNodeComponentView = App.HostComponentView.extend(App.Decommissionable, {

  componentForCheckDecommission: 'NAMENODE',

  /**
   * Get component decommission status from server
   * @returns {$.ajax}
   */
  getDNDecommissionStatus: function () {
    // always get datanode decommission statue from active namenode (if NN HA enabled)
    var hdfs = App.HDFSService.find().objectAt(0);
    var activeNNHostName = (!hdfs.get('snameNode') && hdfs.get('activeNameNode')) ? hdfs.get('activeNameNode.hostName') : hdfs.get('nameNode.hostName');
    return App.ajax.send({
      name: 'host.host_component.decommission_status_datanode',
      sender: this,
      data: {
        hostName: activeNNHostName,
        componentName: this.get('componentForCheckDecommission')
      },
      success: 'getDNDecommissionStatusSuccessCallback',
      error: 'getDNDecommissionStatusErrorCallback'
    });
  },

  /**
   * Set received value or null to <code>decommissionedStatusObject</code>
   * @param {Object} response
   * @returns {Object|null}
   */
  getDNDecommissionStatusSuccessCallback: function (response) {
    var statusObject = Em.get(response, 'metrics.dfs.namenode');
    if (!Em.isNone(statusObject)) {
      this.computeStatus(statusObject);
      return statusObject;
    }
    return null;
  },

  /**
   * Set null to <code>decommissionedStatusObject</code> if server returns error
   * @returns {null}
   */
  getDNDecommissionStatusErrorCallback: function () {
    this.set('decommissionedStatusObject', null);
    return null;
  },

  /**
   * load Recommission/Decommission status from adminState of each live node
   */
  loadComponentDecommissionStatus: function () {
    return this.getDNDecommissionStatus();
  },

  setDesiredAdminState: function (desired_admin_state) {
    this.setStatusAs(desired_admin_state);
  },

  /**
   * compute and set decommission state by namenode metrics
   * @param curObj
   */
  computeStatus: function (curObj) {
    var hostName = this.get('content.hostName');

    if (curObj) {
      var liveNodesJson = App.parseJSON(curObj.LiveNodes);
      // HDP-2 stack
      if (liveNodesJson && liveNodesJson[hostName]) {
        switch (liveNodesJson[hostName].adminState) {
          case "In Service":
            this.setStatusAs('INSERVICE');
            break;
          case "Decommission In Progress":
            this.setStatusAs('DECOMMISSIONING');
            break;
          case "Decommissioned":
            this.setStatusAs('DECOMMISSIONED');
            break;
        }
      } else {
        // if namenode is down, get desired_admin_state to decide if the user had issued a decommission
        this.getDesiredAdminState();
      }
    }
  }
});
