chrome-extensions-samples/apps/samples/gdrive/js/util.js

/*
Copyright 2012 Google Inc.

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.

Author: Eric Bidelman (ericbidelman@chromium.org)
*/

var Util = Util || {};

// Combines two JSON objects in one.
Util.merge = function(obj1, obj2) {
  var obj = {};

  for (var x in obj1) {
    if (obj1.hasOwnProperty(x)) {
      obj[x] = obj1[x];
    }
  }

  for (var x in obj2) {
    if (obj2.hasOwnProperty(x)) {
      obj[x] = obj2[x];
    }
  }

  return obj;
};

/**
 * Turns a NodeList into an array.
 *
 * @param {NodeList} list The array-like object.
 * @return {Array} The NodeList as an array.
 */
Util.toArray = function(list) {
  return Array.prototype.slice.call(list || [], 0);
};

/**
 * Urlencodes a JSON object of key/value query parameters.
 * @param {Object} parameters Key value pairs representing URL parameters.
 * @return {string} query parameters concatenated together.
 */
Util.stringify = function(parameters) {
  var params = [];
  for(var p in parameters) {
    params.push(encodeURIComponent(p) + '=' +
                encodeURIComponent(parameters[p]));
  }
  return params.join('&');
};

/**
 * Creates a JSON object of key/value pairs
 * @param {string} paramStr A string of Url query parmeters.
 *    For example: max-results=5&startindex=2&showfolders=true
 * @return {Object} The query parameters as key/value pairs.
 */
Util.unstringify = function(paramStr) {
  var parts = paramStr.split('&');

  var params = {};
  for (var i = 0, pair; pair = parts[i]; ++i) {
    var param = pair.split('=');
    params[decodeURIComponent(param[0])] = decodeURIComponent(param[1]);
  }
  return params;
};

/**
 * Utility for formatting a date string.
 * @param {string} msg The date in UTC format. Example: 2010-04-01T08:00:00Z.
 * @return {string} The date formated as mm/dd/yy. Example: 04/01/10.
 */
Util.formatDate = function(dateStr) {
  var date = new Date(dateStr.split('T')[0]);
  return [date.getMonth() + 1, date.getDate(),
          date.getFullYear().toString().substring(2)].join('/');
};

/**
 * Utility for formatting a Date object as a string in ISO 8601 format using UTC.
 * @param {Date} d The date to format.
 * @return {string} The formated date string in ISO 8601 format.
 */
Util.ISODateString = function(d) {
 var pad = function(n) {
   return n < 10 ? '0' + n : n;
 };
 return d.getUTCFullYear() + '-'
        + pad(d.getUTCMonth() + 1) + '-'
        + pad(d.getUTCDate()) + 'T'
        + pad(d.getUTCHours()) + ':'
        + pad(d.getUTCMinutes()) + ':'
        + pad(d.getUTCSeconds());// + 'Z'
};

/** 
 * Formats a string with the given parameters. The string to format must have
 * placeholders that correspond to the index of the arguments passed and surrounded 
 * by curly braces (e.g. 'Some {0} string {1}').
 *
 * @param {string} var_args The string to be formatted should be the first 
 *     argument followed by the variables to inject into the string
 * @return {string} The string with the specified parameters injected
 */
Util.format = function(var_args) {
  var args = Array.prototype.slice.call(arguments, 1);
  return var_args.replace(/\{(\d+)\}/g, function(m, i) {
    return args[i];
  });
};

Util.sortByDate = function(a, b) {
  if (a.updatedDateFull < b.updatedDateFull) {
    return 1;
  }
  if (a.updatedDateFull > b.updatedDateFull) {
    return -1;
  }
  return 0;
}

Util.sortByTitle = function(a, b) {
  if (a.title < b.title) {
    return 1;
  }
  if (a.title > b.title) {
    return -1;
  }
  return 0;
}