/*
 * Copyright 2012, Mozilla Foundation and contributors
 *
 * 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.
 */

'use strict';

/**
 * Fake a console for IE9
 */
if (typeof window !== 'undefined' && window.console == null) {
  window.console = {};
}
'debug,log,warn,error,trace,group,groupEnd'.split(',').forEach(function(f) {
  if (typeof window !== 'undefined' && !window.console[f]) {
    window.console[f] = function() {};
  }
});

/**
 * Fake Element.classList for IE9
 * Based on https://gist.github.com/1381839 by Devon Govett
 */
if (typeof document !== 'undefined' && typeof HTMLElement !== 'undefined' &&
        !('classList' in document.documentElement) && Object.defineProperty) {
  Object.defineProperty(HTMLElement.prototype, 'classList', {
    get: function() {
      var self = this;
      function update(fn) {
        return function(value) {
          var classes = self.className.split(/\s+/);
          var index = classes.indexOf(value);
          fn(classes, index, value);
          self.className = classes.join(' ');
        };
      }

      var ret = {
        add: update(function(classes, index, value) {
          ~index || classes.push(value);
        }),
        remove: update(function(classes, index) {
          ~index && classes.splice(index, 1);
        }),
        toggle: update(function(classes, index, value) {
          ~index ? classes.splice(index, 1) : classes.push(value);
        }),
        contains: function(value) {
          return !!~self.className.split(/\s+/).indexOf(value);
        },
        item: function(i) {
          return self.className.split(/\s+/)[i] || null;
        }
      };

      Object.defineProperty(ret, 'length', {
        get: function() {
          return self.className.split(/\s+/).length;
        }
      });

      return ret;
    }
  });
}

/**
 * Array.find
 * https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/find
 */
if (!Array.prototype.find) {
  Object.defineProperty(Array.prototype, 'find', {
    enumerable: false,
    configurable: true,
    writable: true,
    value: function(predicate) {
      if (this == null) {
        throw new TypeError('Array.prototype.find called on null or undefined');
      }
      if (typeof predicate !== 'function') {
        throw new TypeError('predicate must be a function');
      }
      var list = Object(this);
      var length = list.length >>> 0;
      var thisArg = arguments[1];
      var value;

      for (var i = 0; i < length; i++) {
        if (i in list) {
          value = list[i];
          if (predicate.call(thisArg, value, i, list)) {
            return value;
          }
        }
      }
      return undefined;
    }
  });
}

/**
 * String.prototype.trimLeft is non-standard, but it works in Firefox,
 * Chrome and Opera. It's easiest to create a shim here.
 */
if (!String.prototype.trimLeft) {
  String.prototype.trimLeft = function() {
    return String(this).replace(/\s*$/, '');
  };
}

/**
 * Polyfil taken from
 * https://developer.mozilla.org/en-US/docs/JavaScript/Reference/Global_Objects/Function/bind
 */
if (!Function.prototype.bind) {
  Function.prototype.bind = function(oThis) {
    if (typeof this !== 'function') {
      // closest thing possible to the ECMAScript 5 internal IsCallable function
      throw new TypeError('Function.prototype.bind - what is trying to be bound is not callable');
    }

    var aArgs = Array.prototype.slice.call(arguments, 1),
        fToBind = this,
        fNOP = function () {},
        fBound = function () {
          return fToBind.apply(this instanceof fNOP && oThis
                                 ? this
                                 : oThis,
                               aArgs.concat(Array.prototype.slice.call(arguments)));
        };

    fNOP.prototype = this.prototype;
    fBound.prototype = new fNOP();
    return fBound;
  };
}
