goog.provide('ol.TileBounds');

goog.require('goog.asserts');
goog.require('goog.math.Box');
goog.require('ol.TileCoord');



/**
 * @constructor
 * @extends {goog.math.Box}
 * @param {number} top Top.
 * @param {number} right Right.
 * @param {number} bottom Bottom.
 * @param {number} left Left.
 */
ol.TileBounds = function(top, right, bottom, left) {

  goog.asserts.assert(top <= bottom);
  goog.asserts.assert(left <= right);

  goog.base(this, top, right, bottom, left);

};
goog.inherits(ol.TileBounds, goog.math.Box);


/**
 * @param {number} z Z.
 * @param {function(this: T, ol.TileCoord): boolean} f Callback.
 * @param {T=} opt_obj The object to be used for the value of 'this' within f.
 * @template T
 */
ol.TileBounds.prototype.forEachTileCoord = function(z, f, opt_obj) {
  var tileCoord = new ol.TileCoord(z, 0, 0);
  var x, y;
  for (x = this.left; x <= this.right; ++x) {
    tileCoord.x = x;
    for (y = this.top; y <= this.bottom; ++y) {
      tileCoord.y = y;
      if (f.call(opt_obj, tileCoord)) {
        return;
      }
      goog.asserts.assert(tileCoord.z == z);
      goog.asserts.assert(tileCoord.x == x);
      goog.asserts.assert(tileCoord.y == y);
    }
  }
};


/**
 * @param {...ol.TileCoord} var_args Tile coordinates.
 * @return {!ol.TileBounds} Bounding tile box.
 */
ol.TileBounds.boundingTileBounds = function(var_args) {
  var tileCoord0 = arguments[0];
  var tileBounds = new ol.TileBounds(tileCoord0.y, tileCoord0.x,
                                     tileCoord0.y, tileCoord0.x);
  var i;
  for (i = 1; i < arguments.length; ++i) {
    var tileCoord = arguments[i];
    goog.asserts.assert(tileCoord.z == tileCoord0.z);
    tileBounds.top = Math.min(tileBounds.top, tileCoord.y);
    tileBounds.right = Math.max(tileBounds.right, tileCoord.x);
    tileBounds.bottom = Math.max(tileBounds.bottom, tileCoord.y);
    tileBounds.left = Math.min(tileBounds.left, tileCoord.x);
  }
  return tileBounds;
};