Refactor the session resumption code and fix a bug after recent merge.

Split the code into two new methods for the prebind and non-prebind
usecase.

converse.js

@@ -5671,52 +5671,45 @@
             });
         };
 
-        this.initConnection = function () {
-            var rid, sid, jid;
-            if (this.connection && this.connection.connected) {
-                this.setUpXMLLogging();
-                this.onConnected();
-            } else {
-                if (!this.bosh_service_url && ! this.websocket_url) {
-                    throw new Error("initConnection: you must supply a value for either the bosh_service_url or websocket_url or both.");
-                }
-                if (('WebSocket' in window || 'MozWebSocket' in window) && this.websocket_url) {
-                    this.connection = new Strophe.Connection(this.websocket_url);
-                } else if (this.bosh_service_url) {
-                    this.connection = new Strophe.Connection(this.bosh_service_url);
-                } else {
-                    throw new Error("initConnection: this browser does not support websockets and bosh_service_url wasn't specified.");
-                }
-                this.setUpXMLLogging();
-
+        this.attemptPreboundSession = function (tokens) {
+            /* Handle session resumption or initialization when prebind is being used.
+             */
+            var rid = tokens.rid, jid = tokens.jid, sid = tokens.sid;
             if (this.keepalive) {
                 if (!this.jid) {
                     throw new Error("initConnection: when using 'keepalive' with 'prebind, you must supply the JID of the current user.");
                 }
-                    rid = this.session.get('rid');
-                    sid = this.session.get('sid');
-                    jid = this.session.get('jid');
+                if (rid && sid && jid && Strophe.getBareJidFromJid(jid) === Strophe.getBareJidFromJid(this.jid)) {
+                    this.session.save({rid: rid}); // The RID needs to be increased with each request.
+                    return this.connection.attach(jid, sid, rid, this.onConnStatusChanged);
                 }
-                if (this.authentication === PREBIND) {
-                    if (!this.keepalive) {
+            } else { // Not keepalive
                 if (this.jid && this.sid && this.rid) {
-                            this.connection.attach(this.jid, this.sid, this.rid, this.onConnStatusChanged);
+                    return this.connection.attach(this.jid, this.sid, this.rid, this.onConnStatusChanged);
                 } else {
                     throw new Error("initConnection: If you use prebind and not keepalive, "+
                         "then you MUST supply JID, RID and SID values");
                 }
             }
-                    if (rid && sid && jid && Strophe.getBareJidFromJid(jid) === Strophe.getBareJidFromJid(this.jid)) {
-                        this.session.save({rid: rid}); // The RID needs to be increased with each request.
-                        this.connection.attach(jid, sid, rid, this.onConnStatusChanged);
-                    } else if (this.prebind_url) {
+            // We haven't been able to attach yet. Let's see if there
+            // is a prebind_url, otherwise there's nothing with which
+            // we can attach.
+            if (this.prebind_url) {
                 this.startNewBOSHSession();
             } else {
                 delete this.connection;
                 this.emit('noResumeableSession');
             }
-                } else {
-                    // Non-prebind case.
+        };
+
+        this.attemptNonPreboundSession = function (tokens) {
+            /* Handle session resumption or initialization when prebind is not being used.
+             *
+             * Two potential options exist and are handled in this method:
+             *  1. keepalive
+             *  2. auto_login
+             */
+            var rid = tokens.rid, jid = tokens.jid, sid = tokens.sid;
             if (this.keepalive && rid && sid && jid) {
                 this.session.save({rid: rid}); // The RID needs to be increased with each request.
                 this.connection.attach(jid, sid, rid, this.onConnStatusChanged);
@@ -5734,6 +5727,36 @@
                     this.connection.connect(this.jid, this.password, this.onConnStatusChanged);
                 }
             }
+        };
+
+        this.initConnection = function () {
+            var tokens = {};
+            if (this.connection && this.connection.connected) {
+                this.setUpXMLLogging();
+                this.onConnected();
+            } else {
+                if (!this.bosh_service_url && ! this.websocket_url) {
+                    throw new Error("initConnection: you must supply a value for either the bosh_service_url or websocket_url or both.");
+                }
+                if (('WebSocket' in window || 'MozWebSocket' in window) && this.websocket_url) {
+                    this.connection = new Strophe.Connection(this.websocket_url);
+                } else if (this.bosh_service_url) {
+                    this.connection = new Strophe.Connection(this.bosh_service_url);
+                } else {
+                    throw new Error("initConnection: this browser does not support websockets and bosh_service_url wasn't specified.");
+                }
+                this.setUpXMLLogging();
+                if (this.keepalive) {
+                    tokens.rid = this.session.get('rid');
+                    tokens.sid = this.session.get('sid');
+                    tokens.jid = this.session.get('jid');
+                }
+                // We now try to resume or automatically set up a new session.
+                // Otherwise the user will be shown a login form.
+                if (this.authentication === PREBIND) {
+                    this.attemptPreboundSession(tokens);
+                } else {
+                    this.attemptNonPreboundSession(tokens);
                 }
             }
         };