canvas-lms/public/javascripts/jquery.instructure_misc_helpers.js

/*
 * Copyright (C) 2011 - present Instructure, Inc.
 *
 * This file is part of Canvas.
 *
 * Canvas is free software: you can redistribute it and/or modify it under
 * the terms of the GNU Affero General Public License as published by the Free
 * Software Foundation, version 3 of the License.
 *
 * Canvas is distributed in the hope that it will be useful, but WITHOUT ANY
 * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
 * A PARTICULAR PURPOSE. See the GNU Affero General Public License for more
 * details.
 *
 * You should have received a copy of the GNU Affero General Public License along
 * with this program. If not, see <http://www.gnu.org/licenses/>.
 */

import INST from './INST'
import I18n from 'i18n!instructure'
import $ from 'jquery'
import htmlEscape from './str/htmlEscape'

  // Return the first value which passes a truth test
  $.detect = function(collection, callback) {
    var result;
    $.each(collection, function(index, value) {
      if (callback.call(value, value, index, collection)) {
        result = value;
        return false; // we found it, break the $.each() loop iteration by returning false
      }
    });
    return result;
  };

  $.encodeToHex = function(str) {
    var hex = "";
    var e = str.length;
    var c = 0;
    var h;
    for (var i = 0; i < str.length; i++) {
      var part = str.charCodeAt(i).toString(16);
      while (part.length < 2) {
        part = "0" + part;
      }
      hex += part;
    }
    return hex;
  };
  $.decodeFromHex = function(str) {
    var r='';
    var i = 0;
    while(i < str.length){
      r += unescape('%'+str.substring(i,i+2));
      i += 2;
    }
    return r;
  };

  // useful for i18n, e.g. t('key', 'pick one: %{select}', {select: $.raw('<select><option>...')})
  // note that raw returns a SafeString object, so you may want to call toString
  // if you're using it elsewhere
  $.raw = function(str) {
    return new htmlEscape.SafeString(str);
  }
  // ensure the jquery html setters don't puke if given a SafeString
  $.each(["html", "append", "prepend"], function(idx, method) {
    var orig = $.fn[method];
    $.fn[method] = function() {
      var args = [].slice.call(arguments);
      for (var i = 0, len = args.length; i < len; i++) {
        if (args[i] instanceof htmlEscape.SafeString)
          args[i] = args[i].toString();
      }
      return orig.apply(this, args);
    }
  });

  $.replaceOneTag = function(text, name, value) {
    if(!text) { return text; }
    name = (name || "").toString();
    value = (value || "").toString().replace(/\s/g, "+");
    var itemExpression = new RegExp("(%7B|{){2}[\\s|%20|\+]*" + name + "[\\s|%20|\+]*(%7D|}){2}", 'g');
    return text.replace(itemExpression, value);
  };
  // backwards compatible with only one tag
  $.replaceTags = function(text, mapping_or_name, maybe_value) {
    if (typeof mapping_or_name == 'object') {
      for (var name in mapping_or_name) {
        text = $.replaceOneTag(text, name, mapping_or_name[name])
      }
      return text;
    } else {
      return $.replaceOneTag(text, mapping_or_name, maybe_value)
    }
  }

  $.underscore = function(string) {
    return (string || "").replace(/([A-Z])/g, "_$1").replace(/^_/, "").toLowerCase();
  };

  $.titleize = function(string) {
    var res = (string || "").replace(/([A-Z])/g, " $1").replace(/_/g, " ").replace(/\s+/, " ").replace(/^\s/, "");
    return $.map(res.split(/\s/), function(word) { return (word[0] || "").toUpperCase() + word.substring(1); }).join(" ");
  };

  $.fileSize = function(bytes) {
    var factor = 1024;
    if(bytes < factor) {
      return parseInt(bytes, 10) + " bytes";
    } else if(bytes < factor * factor) {
      return parseInt(bytes / factor, 10) + "KB";
    } else {
      return (Math.round(10.0 * bytes / factor / factor) / 10.0) + "MB";
    }
  };

  $.toSentence = function(array, options) {
    if (typeof options == 'undefined') {
      options = {};
    } else if (options == 'or') {
      options = {
        two_words_connector: I18n.t('#support.array.or.two_words_connector'),
        last_word_connector: I18n.t('#support.array.or.last_word_connector')
      };
    }

    options = $.extend({
        words_connector: I18n.t('#support.array.words_connector'),
        two_words_connector: I18n.t('#support.array.two_words_connector'),
        last_word_connector: I18n.t('#support.array.last_word_connector')
      }, options);

    switch (array.length) {
      case 0:
        return '';
      case 1:
        return '' + array[0];
      case 2:
        return array[0] + options.two_words_connector + array[1];
      default:
        return array.slice(0, -1).join(options.words_connector) + options.last_word_connector + array[array.length - 1];
    }
  }

  // return query string parameter
  // $.queryParam("name") => qs value or null
  $.queryParam = function(name) {
    name = name.replace(/[\[]/,"\\\[").replace(/[\]]/,"\\\]");
    var regex = new RegExp("[\\?&]"+name+"=([^&#]*)");
    var results = regex.exec(window.location.search);
    if(results == null)
      return results;
    else
      return decodeURIComponent(results[1].replace(/\+/g, " "));
  };

  $.capitalize = function(string) {
    return string.charAt(0).toUpperCase() + string.substring(1).toLowerCase();
  };

  INST.youTubeRegEx = /^https?:\/\/(www\.youtube\.com\/watch.*v(=|\/)|youtu\.be\/)([^&#]*)/;
  $.youTubeID = function(path) {
    var match = path.match(INST.youTubeRegEx);
    if(match && match[match.length - 1]) {
      return match[match.length - 1];
    }
    return null;
  };