text: /*global define*/
  define([
          '../Core/defaultValue',
          '../Core/defined',
          '../Core/defineProperties',
          '../Core/DeveloperError',
          '../Core/Event',
          '../Core/ReferenceFrame',
          '../Core/TimeIntervalCollection',
          './PositionProperty',
          './Property'
      ], function(
          defaultValue,
          defined,
          defineProperties,
          DeveloperError,
          Event,
          ReferenceFrame,
          TimeIntervalCollection,
          PositionProperty,
          Property) {
      "use strict";
  
      /**
       * A {@link TimeIntervalCollectionProperty} which is also a {@link PositionProperty}.
       *
       * @alias TimeIntervalCollectionPositionProperty
       * @constructor
       *
       * @param {ReferenceFrame} [referenceFrame=ReferenceFrame.FIXED] The reference frame in which the position is defined.
       */
      var TimeIntervalCollectionPositionProperty = function(referenceFrame) {
          this._definitionChanged = new Event();
          this._intervals = new TimeIntervalCollection();
          this._intervals.changedEvent.addEventListener(TimeIntervalCollectionPositionProperty.prototype._intervalsChanged, this);
          this._referenceFrame = defaultValue(referenceFrame, ReferenceFrame.FIXED);
      };
  
      defineProperties(TimeIntervalCollectionPositionProperty.prototype, {
          /**
           * Gets a value indicating if this property is constant.  A property is considered
           * constant if getValue always returns the same result for the current definition.
           * @memberof TimeIntervalCollectionPositionProperty.prototype
           *
           * @type {Boolean}
           * @readonly
           */
          isConstant : {
              get : function() {
                  return this._intervals.isEmpty;
              }
          },
          /**
           * Gets the event that is raised whenever the definition of this property changes.
           * The definition is considered to have changed if a call to getValue would return
           * a different result for the same time.
           * @memberof TimeIntervalCollectionPositionProperty.prototype
           *
           * @type {Event}
           * @readonly
           */
          definitionChanged : {
              get : function() {
                  return this._definitionChanged;
              }
          },
          /**
           * Gets the interval collection.
           * @memberof TimeIntervalCollectionPositionProperty.prototype
           * @type {TimeIntervalCollection}
           */
          intervals : {
              get : function() {
                  return this._intervals;
              }
          },
          /**
           * Gets the reference frame in which the position is defined.
           * @memberof TimeIntervalCollectionPositionProperty.prototype
           * @type {ReferenceFrame}
           * @default ReferenceFrame.FIXED;
           */
          referenceFrame : {
              get : function() {
                  return this._referenceFrame;
              }
          }
      });
  
      /**
       * Gets the value of the property at the provided time in the fixed frame.
       *
       * @param {JulianDate} time The time for which to retrieve the value.
       * @param {Object} [result] The object to store the value into, if omitted, a new instance is created and returned.
       * @returns {Object} The modified result parameter or a new instance if the result parameter was not supplied.
       */
      TimeIntervalCollectionPositionProperty.prototype.getValue = function(time, result) {
          return this.getValueInReferenceFrame(time, ReferenceFrame.FIXED, result);
      };
  
      /**
       * Gets the value of the property at the provided time and in the provided reference frame.
       *
       * @param {JulianDate} time The time for which to retrieve the value.
       * @param {ReferenceFrame} referenceFrame The desired referenceFrame of the result.
       * @param {Cartesian3} [result] The object to store the value into, if omitted, a new instance is created and returned.
       * @returns {Cartesian3} The modified result parameter or a new instance if the result parameter was not supplied.
       */
      TimeIntervalCollectionPositionProperty.prototype.getValueInReferenceFrame = function(time, referenceFrame, result) {
          //>>includeStart('debug', pragmas.debug);
          if (!defined(time)) {
              throw new DeveloperError('time is required.');
          }
          if (!defined(referenceFrame)) {
              throw new DeveloperError('referenceFrame is required.');
          }
          //>>includeEnd('debug');
  
          var position = this._intervals.findDataForIntervalContainingDate(time);
          if (defined(position)) {
              return PositionProperty.convertToReferenceFrame(time, position, this._referenceFrame, referenceFrame, result);
          }
          return undefined;
      };
  
      /**
       * Compares this property to the provided property and returns
       * <code>true</code> if they are equal, <code>false</code> otherwise.
       *
       * @param {Property} [other] The other property.
       * @returns {Boolean} <code>true</code> if left and right are equal, <code>false</code> otherwise.
       */
      TimeIntervalCollectionPositionProperty.prototype.equals = function(other) {
          return this === other || //
                 (other instanceof TimeIntervalCollectionPositionProperty && //
                  this._intervals.equals(other._intervals, Property.equals) && //
                  this._referenceFrame === other._referenceFrame);
      };
  
      /**
       * @private
       */
      TimeIntervalCollectionPositionProperty.prototype._intervalsChanged = function() {
          this._definitionChanged.raiseEvent(this);
      };
  
      return TimeIntervalCollectionPositionProperty;
  });