// 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.
 *
 * @author eae@google.com (Emil A Eklund)
 */

goog.provide('goog.positioning.ViewportPosition');

goog.require('goog.math.Coordinate');
goog.require('goog.positioning');
goog.require('goog.positioning.AbstractPosition');
goog.require('goog.positioning.Corner');
goog.require('goog.style');



/**
 * 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.
 * @override
 */
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);
};
