/*! jquery.hub - v0.5.0 - 2013-02-14
* https://github.com/JamesMGreene/jquery.hub
* Copyright (c) 2013 James M. Greene; Licensed MIT */
/*global OpenAjax*/
// questionable if should be plugin  https://github.com/cowboy/talks/blob/master/jquery-plugin-authoring.js
(function($) {
  "use strict";
  
  var hubOptions = {},
      readylist = null;

  $.hub = function(options) {
    if (options.ready === false) {
      // http://api.jquery.com/category/deferred-object/
      readylist = $.Deferred();
      hubOptions.ready = false;
    }
    if (options.ready) {
      if (readylist) {
          // execute any callbacks that were added
          readylist.resolve();
      }
    }
    return hubOptions;
  };


  /**
  * From: http://stackoverflow.com/questions/105034/how-to-create-a-guid-uuid-in-javascript/2117523#2117523
  */
  $.hub.guid = function() {
    return "xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxx".replace(/[xy]/g, function(c) {
      var r = Math.random() * 16 | 0,
          v = (c === "x" ? r : (r & 0x3 | 0x8));

      return v.toString(16);
    });
  };

  $.hub.message = function(body, options) {
    var message = {},
        messageOptions = options || {};

    message.body = body;
    message.timestamp = (new Date()).getTime();
    message.messageId = $.hub.guid();
    message.formatVersion = messageOptions.formatVersion || "0";

    return message;
  };

  $.hub.subscribe = function(channel, callback, scope, subscriberData, filter) {
    var callbackProxy = callback,
        filterProxy = filter;

    if (scope) {
      callbackProxy = $.proxy(callback, scope);
    }
    if (filter && hubOptions.stringify) {
      filterProxy = function(channel, message) {
        return filter(channel, JSON.parse(message));
      };
    }
    return OpenAjax.hub.subscribe(channel /*name*/,
      function(channel, message) { callbackProxy(channel, (hubOptions.stringify ? JSON.parse(message) : message)); },
      null,  /* null scope because of $.proxy */
      subscriberData,
      filterProxy);
  };

  $.hub.unsubscribe = function(subscription) {
    OpenAjax.hub.unsubscribe(subscription);
  };

  var _publish = function(channel, message) {
    try {
      if (hubOptions.stringify) {
        message = JSON.stringify(message);
      }
      OpenAjax.hub.publish(channel /*name*/, message /*data*/);
    }
    catch (e) {
      // Eat it
    }
  };

  $.hub.publish = function(channel, message) {
    if (readylist) {
      // add a callback to be executed when the deferred is resolved
      readylist.done(function() {
          _publish(channel, message);
      });
    }
    else {
      _publish(channel, message);
    }
  };

  $.hub.createVersionFilter = function(version) {
    var major, minor;

    version = /(\d+)\.?(\d+)?\.?(\d+)?/.exec(version);
    major = parseInt( version[1], 10 ) || 0;
    minor = parseInt( version[2], 10 ) || 0;

    var filter = function(channel, message) {
      var messageVersion = /(\d+)\.?(\d+)?\.?(\d+)?/.exec((message ? message.formatVersion : "")),
          messageMajor = parseInt(messageVersion[1], 10) || 0,
          messageMinor = parseInt(messageVersion[2], 10) || 0;
      return (major === messageMajor && (minor ? minor === messageMinor : true));
    };

    return filter;
  };

  $.hub.createIdempotentFilter = function() {
    var messageIds = {};
    var filter = function(channel, message) {
      if (message && message.messageId) {
        if (messageIds[message.messageId]) {
          return false;
        }
        else {
          messageIds[message.messageId] = message.timestamp;
        }
      }

      return true;
    };

    return filter;
  };

  $.hub.reply = function(message, replyMessage) {
    if (message && replyMessage && message.replyTo) {
      replyMessage.correlationId = message.messageId;
      $.hub.publish(message.replyTo, replyMessage);
      return true;
    }

    return false;
  };

  $.hub.requestReply = function(channel, message, callback) {
    var replyChannel = $.hub.guid(),
        subscription = $.hub.subscribe(replyChannel, function(channel, message) {
          callback(channel, message);
          $.hub.unsubscribe(subscription);
        });

    message.replyTo = replyChannel;
    $.hub.publish(channel, message);
  };

  // exposed for automated testing purposes
  $.hub._reset = function() {
    hubOptions.ready = true;
    hubOptions.stringify = true;
    readylist = null;
    if (OpenAjax.hub.reinit) {
      OpenAjax.hub.reinit();
    }
  };

  // before returning, initialize the hubOptions
  $.hub._reset();

})(jQuery);