text: // Copyright 2006 The Closure Library Authors. All Rights Reserved.
  //
  // 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
  //
  //      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.
  
  /**
   * @fileoverview Client positioning class.
   *
   */
  
  goog.provide('goog.positioning.ViewportPosition');
  
  goog.require('goog.math.Box');
  goog.require('goog.math.Coordinate');
  goog.require('goog.math.Size');
  goog.require('goog.positioning.AbstractPosition');
  
  
  
  /**
   * Encapsulates a popup position where the popup is positioned according to
   * coordinates relative to the  element's viewport (page). This calculates the
   * correct position to use even if the element is relatively positioned to some
   * other element.
   *
   * @param {number|goog.math.Coordinate} arg1 Left position or coordinate.
   * @param {number=} opt_arg2 Top position.
   * @constructor
   * @extends {goog.positioning.AbstractPosition}
   */
  goog.positioning.ViewportPosition = function(arg1, opt_arg2) {
    this.coordinate = arg1 instanceof goog.math.Coordinate ? arg1 :
          new goog.math.Coordinate(/** @type {number} */ (arg1), opt_arg2);
  };
  goog.inherits(goog.positioning.ViewportPosition,
                goog.positioning.AbstractPosition);
  
  
  /**
   * Repositions the popup according to the current state
   *
   * @param {Element} element The DOM element of the popup.
   * @param {goog.positioning.Corner} popupCorner The corner of the popup
   *     element that that should be positioned adjacent to the anchorElement.
   * @param {goog.math.Box=} opt_margin A margin specified in pixels.
   * @param {goog.math.Size=} opt_preferredSize Preferred size of the element.
   */
  goog.positioning.ViewportPosition.prototype.reposition = function(
      element, popupCorner, opt_margin, opt_preferredSize) {
    goog.positioning.positionAtAnchor(
        goog.style.getClientViewportElement(element),
        goog.positioning.Corner.TOP_LEFT, element, popupCorner,
        this.coordinate, opt_margin, null, opt_preferredSize);
  };
  