/**
 * 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.MainAlertInstancesController = Em.Controller.extend({

  name: 'mainAlertInstancesController',

  /**
   * Are alertInstances loaded
   * @type {boolean}
   */
  isLoaded: false,

  /**
   * A flag to reload alert instances table every 10 seconds
   * @type {boolean}
   */
  reload: false,

  /**
   * Causes automatic updates of content if set to true
   * @type {boolean}
   */
  isUpdating: false,

  /**
   * Times for alert instances updater
   * Used in <code>scheduleUpdate</code>
   * @type {number|null}
   */
  updateTimer: null,

  /**
   * @type {string|null} sourceName - hostName or alertDefinitionId
   */
  sourceName: null,

  /**
   * @type {string|null} sourceType - 'HOST'|'ALERT_DEFINITION'
   */
  sourceType: null,

  /**
   * Load alert instances from server (all, for selected host, for selected alert definition)
   * @returns {$.ajax}
   * @method fetchAlertInstances
   */
  fetchAlertInstances: function () {
    var sourceType = this.get('sourceType'),
      sourceName = this.get('sourceName'),
      ajaxData = {
        sender: this,
        success: 'getAlertInstancesSuccessCallback',
        error: 'getAlertInstancesErrorCallback'
      };

    switch (sourceType) {
      case 'HOST':
        $.extend(ajaxData, {
          name: 'alerts.instances.by_host',
          data: {
            hostName: sourceName
          }
        });
        break;

      case 'ALERT_DEFINITION':
        $.extend(ajaxData, {
          name: 'alerts.instances.by_definition',
          data: {
            definitionId: sourceName
          }
        });
        break;

      default:
        $.extend(ajaxData, {
          name: 'alerts.instances'
        });
        break;
    }

    return App.ajax.send(ajaxData);
  },

  /**
   * Pseudo for <code>fetchAlertInstances</code>
   * Used to get all alert instances
   * @method loadAlertInstances
   */
  loadAlertInstances: function () {
    this.set('isLoaded', false);
    this.set('sourceType', null);
    this.set('sourceName', null);
    this.fetchAlertInstances();
  },

  /**
   * Pseudo for <code>fetchAlertInstances</code>
   * Used to get alert instances for some host
   * @param {string} hostName
   * @method loadAlertInstancesByHost
   */
  loadAlertInstancesByHost: function (hostName) {
    this.set('isLoaded', false);
    this.set('sourceType', 'HOST');
    this.set('sourceName', hostName);
    this.fetchAlertInstances();
  },

  /**
   * Pseudo for <code>fetchAlertInstances</code>
   * Used to get alert instances for some alert definition
   * @param {string} definitionId
   * @method loadAlertInstancesByAlertDefinition
   */
  loadAlertInstancesByAlertDefinition: function (definitionId) {
    this.set('isLoaded', false);
    this.set('sourceType', 'ALERT_DEFINITION');
    this.set('sourceName', definitionId);
    this.fetchAlertInstances();
  },

  scheduleUpdate: function () {
    var self = this;
    if (this.get('isUpdating')) {
      this.set('updateTimer', setTimeout(function () {
        self.fetchAlertInstances();
        self.scheduleUpdate();
      }, App.get('alertInstancesUpdateInterval')));
    }
    else {
      clearTimeout(this.get('updateTimer'));
    }
  }.observes('isUpdating'),

  /**
   * Success-callback for alert instances request
   * @param {object} json
   * @method getAlertInstancesSuccessCallback
   */
  getAlertInstancesSuccessCallback: function (json) {
    App.alertInstanceMapper.map(json);
    this.set('isLoaded', true);
    this.set('reload', !this.get('reload'));
  },

  /**
   * Error-callback for alert instances request
   * @method getAlertInstancesErrorCallback
   */
  getAlertInstancesErrorCallback: function () {
    this.set('isLoaded', true);
  }

});
