file.js

// @since 20160221
// singleton inspiration: http://www.dofactory.com/javascript/singleton-design-pattern
var bbsengine = (function () {
    var instance;
 
    function createinstance() 
    {
      return {
        // @since 20160219
        intervals: [],
        visibilityhandler: false,
        // @since 20181021
        currentmemberid: null,
        // @since 20191026
        topbarupdateinterval: 3000,
        // @since 20140210
        logentry: function(message) 
        {
          if (typeof console == "object")
          {
            console.log(message);
          }
          return;
        },
        // @since 20140822
        endswith: function (str, suffix)
        {
          return str.indexOf(suffix, str.length - suffix.length) !== -1;
        },
        appendurlparameter: function (url, param)
        {
          // http://stackoverflow.com/questions/8737615/append-a-param-onto-the-current-url
          var seperator = (url.indexOf("?")===-1)?"?":"&",
              newParam = seperator + param;
          newUrl = url.replace(newParam,"");
          newUrl += newParam;
          return newUrl;
        },
        // http://stackoverflow.com/questions/736513/how-do-i-parse-a-url-into-hostname-and-path-in-javascript
        // @since 20150915
        getlocation: function(href)
        {
          var l = document.createElement("a");
          l.href = href;
          return l;
        },

        initvisibilityeventhandler: function()
        {
          // @see https://developer.mozilla.org/en-US/docs/Web/API/Page_Visibility_API
          var hidden, visibilityChange; 
          if (typeof document.hidden !== "undefined") { // Opera 12.10 and Firefox 18 and later support 
            hidden = "hidden";
            visibilityChange = "visibilitychange";
          } else if (typeof document.mozHidden !== "undefined") {
            hidden = "mozHidden";
            visibilityChange = "mozvisibilitychange";
          } else if (typeof document.msHidden !== "undefined") {
            hidden = "msHidden";
            visibilityChange = "msvisibilitychange";
          } else if (typeof document.webkitHidden !== "undefined") {
            hidden = "webkitHidden";
            visibilityChange = "webkitvisibilitychange";
          }
          // If the page is hidden, stop the intervals
          // if the page is shown, restart the intervals
          function handleVisibilityChange() 
          {
//            instance.logentry("handlevisibilitychange.100: called");
            if (document[hidden])
            {
              be.cancelintervals();
            } 
            else 
            {
              be.restartintervals();
            }
          }

          if (typeof document.addEventListener === "undefined" || typeof hidden === "undefined") 
          {
            instance.logentry("This site requires a browser, such as Google Chrome or Firefox, that supports the Page Visibility API.");
          } 
          else 
          {
            // Handle page visibility change   
            document.addEventListener(visibilityChange, handleVisibilityChange, false);
          }
        },
        
        addinterval: function(interval, note, func)
        {
          if (interval === null || interval < 100)
          {
            instance.logentry("addinterval.100: "+note+": invalid interval");
            return;
          }
          id = setInterval(func, interval);
          this.intervals.push([id, interval, func, note]);
          instance.logentry("addinterval.110: id="+id+" interval="+interval+" note="+note);
          if (this.visibilityhandler === false)
          {
//            instance.logentry("init visibility event handler");
            this.initvisibilityeventhandler();
            this.visibilityhandler = true;
          }
          return;
        },
        cancelintervals: function() {
          logentry = instance.logentry;
          logentry("canceling intervals");
          this.intervals.forEach(function (item, index, arr) {
            id = item[0];
            clearInterval(id);
//            logentry("cancelintervals.100: id="+id);
          });
          return;
        },
        restartintervals: function() {
          logentry = instance.logentry;
          logentry("restarting intervals");
          this.intervals.forEach(function (item, index, arr) {
            oldid = item[0];
            interval = item[1];
            func = item[2];
            note = item[3];
            id = setInterval(func, interval);
            logentry("id="+id+" interval="+interval+" note="+note);
            arr[index][0] = id;
          });
          return;
        },
        settopbarupdateinterval: function(interval) {
          this.topbarupdateinterval = interval;
        },
        gettopbarupdateinterval: function() {
          return this.topbarupdateinterval || 5000;
        },
        // from http://mediocredeveloper.com/wp/?p=55
        hashcode: function(str) {
          // instance.logentry("hashcode.100: s="+JSON.stringify(typeof s));
          if (typeof str  !== "string")
          {
            instance.logentry("hashcode passed a non-string");
            return -1;
          }
          var hash = 0;
          if (str.length === 0) return hash;
          for (i = 0; i < str.length; i++) {
            ch = str.charCodeAt(i);
            hash = ((hash << 5)-hash) + ch;
            hash = hash & hash; // Convert to 32bit integer
          }
          // it would be nice if this could be unsigned
          hash = Math.abs(hash);
          hash = hash.toString(16);
          return hash;
        },
        // @since 20180916
        updatetopbaritem: function(label, selector, url) {
          // be.logentry("updatetopbaritem.100: running");
          if (selector === undefined || selector.length === 0) {
            // be.logentry("updatetopbaritem: "+label+" selector is undefined");
            return;
          }
          // be.logentry("updatetopbaritem: url="+url);

          $.ajax({
            type: "GET",
            dataType: "jsonp",
            url: url,
            error: function(xhr, type, exception) {
              var err = "textStatus="+JSON.stringify(xhr) + ' type=' + type + " exception="+JSON.stringify(exception);
              be.logentry("updatetopbaritem.error: "+ err);
            }, /* end 'error' */
            success: function(payload) {
              var oldfragment = selector;
              var fragment = null;

              var a = selector.clone();
              var b = a.wrap("<div>");
              var c = b.parent();
              var d = c.html();
              oldfragment = d;
              // be.logentry("label: " + label);
              if (oldfragment === undefined)
              {
                be.logentry("updatetopbaritem.success.100: oldfragment is undefined");
                return;
              }
              fragment = payload.fragment.trim();

              if (fragment != oldfragment) {
                be.logentry("fragment="+JSON.stringify(fragment));
                be.logentry("oldfragment="+JSON.stringify(oldfragment));
                be.logentry("updatetopbar.success.100: fragment != oldfragment. updating");
                selector.fadeOut({
                  duration: 350,
                  complete: function(data) {
                    // be.logentry("updatetopbar.fadeout.complete: oldfragment="+JSON.stringify(oldfragment));
                    
                    selector.replaceWith(fragment);
                    selector.fadeIn(500);
                    
                    oldfragment = fragment;
                  }
                });
              } /* oldfragment != fragment */
            } /* end 'success' */
          }); /* .ajax */

        }, /* updatetopbaritem */
        getcurrentmemberid: function () {
          return $.ajax({
            type: "GET",
            dataType: "jsonp",
            url: "//engine.zoidtechnologies.com/getvar-currentmemberid?callback=?",
            error: function(xhr, type, exception) {
              var err = "xhr="+JSON.stringify(xhr) + " type="+type+" exception="+exception;
              be.logentry("getcurrentmemberid.error: "+ err);
              return null;
            }, /* end 'error' */
            success: function(payload) {
//              be.logentry("payload.currentmemberid="+JSON.stringify(payload.currentmemberid));
              return payload.currentmemberid;
            } /* end 'success' */
          }); /* .ajax */
        },
        async function gettopbarupdateinterval() {
          be.logentry("gettopbarinterval async");
          return $.ajax({
            type: "GET",
            dataType: "jsonp",
            url: "//engine.zoidtechnologies.com/getvar-topbarupdateinterval?callback=?",
/*
            error: function(xhr, type, exception) {
              var err = "xhr="+JSON.stringify(xhr) + " type="+type+" exception="+exception;
              be.logentry("gettopbarupdateinterval.error: "+ err);
              return null;
            }, // end error
            success: function(payload) {
//              be.logentry("payload.topbarupdateinterval="+JSON.stringify(payload.topbarupdateinterval));
              return payload.topbarupdateinterval;
            } // end success
*/
          }); /* .ajax */
        }
      };
    }
    return {
        getinstance: function () {
            if (!instance) {
                instance = createinstance();
                instance.getcurrentmemberid().done(function (r) { instance.currentmemberid = r.currentmemberid; });
//                instance.currentmemberid = await instance.getcurrentmemberid();
                instance.topbarupdateinterval = await instance.gettopbarupdateinterval();
/*
                instance.gettopbarupdateinterval()
                  .done(function (r) {
                    instance.logentry("done event for gettopbarupdateinterval(). r.topbarupdateinterval="+JSON.stringify(r.topbarupdateinterval));
                    instance.topbarupdateinterval = r.topbarupdateinterval;
                  });
*/
            }
            instance.logentry("instance.topbarupdateinterval="+JSON.stringify(instance.topbarupdateinterval));
            return instance;
        }
    };
})();

function getbbsengine() {
//  console.log("getbbsengine called");
  return bbsengine.getinstance();
}