From f7c4fd2fedf56d733a87db7077d1d1d88f24bf67 Mon Sep 17 00:00:00 2001
From: lilia <liliakai@gmail.com>
Date: Thu, 14 Jan 2016 14:07:00 -0800
Subject: [PATCH] DRY up event target implementations

Dedupe event target code and make it extensible.

// FREEBIE
---
 Gruntfile.js                      |   1 +
 js/libtextsecure.js               | 202 +++++++++++++-----------------
 libtextsecure/event_target.js     |  79 ++++++++++++
 libtextsecure/message_receiver.js |  61 +--------
 libtextsecure/sync_request.js     |  61 +--------
 5 files changed, 176 insertions(+), 228 deletions(-)
 create mode 100644 libtextsecure/event_target.js

diff --git a/Gruntfile.js b/Gruntfile.js
index ea0ec37ff..576447eb4 100644
--- a/Gruntfile.js
+++ b/Gruntfile.js
@@ -54,6 +54,7 @@ module.exports = function(grunt) {
           'libtextsecure/websocket-resources.js',
           'libtextsecure/helpers.js',
           'libtextsecure/stringview.js',
+          'libtextsecure/event_target.js',
           'libtextsecure/api.js',
           'libtextsecure/account_manager.js',
           'libtextsecure/message_receiver.js',
diff --git a/js/libtextsecure.js b/js/libtextsecure.js
index 79fe86a64..8d0ce4637 100644
--- a/js/libtextsecure.js
+++ b/js/libtextsecure.js
@@ -36181,6 +36181,86 @@ window.textsecure.utils = function() {
     };
 }());
 
+/*
+ * vim: ts=4:sw=4:expandtab
+ *
+ * Implements EventTarget
+ * https://developer.mozilla.org/en-US/docs/Web/API/EventTarget
+ *
+ */
+
+;(function () {
+    'use strict';
+    window.textsecure = window.textsecure || {};
+
+    function EventTarget() {
+    }
+
+    EventTarget.prototype = {
+        constructor: EventTarget,
+        dispatchEvent: function(ev) {
+            if (!(ev instanceof Event)) {
+                throw new Error('Expects an event');
+            }
+            if (this.listeners === null || typeof this.listeners !== 'object') {
+                this.listeners = {};
+            }
+            var listeners = this.listeners[ev.type];
+            if (typeof listeners === 'object') {
+                for (var i=0; i < listeners.length; ++i) {
+                    if (typeof listeners[i] === 'function') {
+                        listeners[i].call(null, ev);
+                    }
+                }
+            }
+        },
+        addEventListener: function(eventName, callback) {
+            if (typeof eventName !== 'string') {
+                throw new Error('First argument expects a string');
+            }
+            if (typeof callback !== 'function') {
+                throw new Error('Second argument expects a function');
+            }
+            if (this.listeners === null || typeof this.listeners !== 'object') {
+                this.listeners = {};
+            }
+            var listeners = this.listeners[eventName];
+            if (typeof listeners !== 'object') {
+                listeners = [];
+            }
+            listeners.push(callback);
+            this.listeners[eventName] = listeners;
+        },
+        removeEventListener: function(eventName, callback) {
+            if (typeof eventName !== 'string') {
+                throw new Error('First argument expects a string');
+            }
+            if (typeof callback !== 'function') {
+                throw new Error('Second argument expects a function');
+            }
+            if (this.listeners === null || typeof this.listeners !== 'object') {
+                this.listeners = {};
+            }
+            var listeners = this.listeners[eventName];
+            for (var i=0; i < listeners.length; ++ i) {
+                if (listeners[i] === callback) {
+                    listeners.splice(i, 1);
+                    return;
+                }
+            }
+            this.listeners[eventName] = listeners;
+        },
+        extend: function(obj) {
+          for (var prop in obj) {
+            this[prop] = obj[prop];
+          }
+          return this;
+        }
+    };
+
+    textsecure.EventTarget = EventTarget;
+}());
+
 /*
  * vim: ts=4:sw=4:expandtab
  */
@@ -36745,7 +36825,9 @@ function MessageReceiver(url, username, password, signalingKey, attachment_serve
     this.number = unencoded[0];
     this.deviceId = unencoded[1];
 }
-MessageReceiver.prototype = {
+
+MessageReceiver.prototype = new textsecure.EventTarget();
+MessageReceiver.prototype.extend({
     constructor: MessageReceiver,
     connect: function() {
         if (this.socket && this.socket.readyState !== WebSocket.CLOSED) {
@@ -37103,63 +37185,8 @@ MessageReceiver.prototype = {
         return Promise.all(promises).then(function() {
             return decrypted;
         });
-    },
-
-    /* Implements EventTarget */
-    dispatchEvent: function(ev) {
-        if (!(ev instanceof Event)) {
-            throw new Error('Expects an event');
-        }
-        if (this.listeners === null || typeof this.listeners !== 'object') {
-            this.listeners = {};
-        }
-        var listeners = this.listeners[ev.type];
-        if (typeof listeners === 'object') {
-            for (var i=0; i < listeners.length; ++i) {
-                if (typeof listeners[i] === 'function') {
-                    listeners[i].call(null, ev);
-                }
-            }
-        }
-    },
-    addEventListener: function(eventName, callback) {
-        if (typeof eventName !== 'string') {
-            throw new Error('First argument expects a string');
-        }
-        if (typeof callback !== 'function') {
-            throw new Error('Second argument expects a function');
-        }
-        if (this.listeners === null || typeof this.listeners !== 'object') {
-            this.listeners = {};
-        }
-        var listeners = this.listeners[eventName];
-        if (typeof listeners !== 'object') {
-            listeners = [];
-        }
-        listeners.push(callback);
-        this.listeners[eventName] = listeners;
-    },
-    removeEventListener: function(eventName, callback) {
-        if (typeof eventName !== 'string') {
-            throw new Error('First argument expects a string');
-        }
-        if (typeof callback !== 'function') {
-            throw new Error('Second argument expects a function');
-        }
-        if (this.listeners === null || typeof this.listeners !== 'object') {
-            this.listeners = {};
-        }
-        var listeners = this.listeners[eventName];
-        for (var i=0; i < listeners.length; ++ i) {
-            if (listeners[i] === callback) {
-                listeners.splice(i, 1);
-                return;
-            }
-        }
-        this.listeners[eventName] = listeners;
     }
-
-};
+});
 
 window.textsecure = window.textsecure || {};
 
@@ -37698,10 +37725,11 @@ textsecure.MessageSender.prototype = {
         sender.sendRequestContactSyncMessage().then(function() {
             sender.sendRequestGroupSyncMessage();
         });
-        this.timeout = setTimout(this.onTimeout.bind(this), 60000);
+        this.timeout = setTimeout(this.onTimeout.bind(this), 60000);
     }
 
-    SyncRequest.prototype = {
+    SyncRequest.prototype = new textsecure.EventTarget();
+    SyncRequest.prototype.extend({
         constructor: SyncRequest,
         onContactSyncComplete: function() {
             this.contactSync = true;
@@ -37726,62 +37754,8 @@ textsecure.MessageSender.prototype = {
             this.receiver.removeEventListener('contactsync', this.oncontact);
             this.receiver.removeEventListener('groupSync', this.ongroup);
             delete this.listeners;
-        },
-
-        /* Implements EventTarget */  /// TODO: Dedupe this same code in MessageReceiver
-        dispatchEvent: function(ev) {
-            if (!(ev instanceof Event)) {
-                throw new Error('Expects an event');
-            }
-            if (this.listeners === null || typeof this.listeners !== 'object') {
-                this.listeners = {};
-            }
-            var listeners = this.listeners[ev.type];
-            if (typeof listeners === 'object') {
-                for (var i=0; i < listeners.length; ++i) {
-                    if (typeof listeners[i] === 'function') {
-                        listeners[i].call(null, ev);
-                    }
-                }
-            }
-        },
-        addEventListener: function(eventName, callback) {
-            if (typeof eventName !== 'string') {
-                throw new Error('First argument expects a string');
-            }
-            if (typeof callback !== 'function') {
-                throw new Error('Second argument expects a function');
-            }
-            if (this.listeners === null || typeof this.listeners !== 'object') {
-                this.listeners = {};
-            }
-            var listeners = this.listeners[eventName];
-            if (typeof listeners !== 'object') {
-                listeners = [];
-            }
-            listeners.push(callback);
-            this.listeners[eventName] = listeners;
-        },
-        removeEventListener: function(eventName, callback) {
-            if (typeof eventName !== 'string') {
-                throw new Error('First argument expects a string');
-            }
-            if (typeof callback !== 'function') {
-                throw new Error('Second argument expects a function');
-            }
-            if (this.listeners === null || typeof this.listeners !== 'object') {
-                this.listeners = {};
-            }
-            var listeners = this.listeners[eventName];
-            for (var i=0; i < listeners.length; ++ i) {
-                if (listeners[i] === callback) {
-                    listeners.splice(i, 1);
-                    return;
-                }
-            }
-            this.listeners[eventName] = listeners;
         }
-    };
+    });
 
     textsecure.SyncRequest = function(sender, receiver) {
         var syncRequest = new SyncRequest(sender, receiver);
diff --git a/libtextsecure/event_target.js b/libtextsecure/event_target.js
new file mode 100644
index 000000000..e3833d631
--- /dev/null
+++ b/libtextsecure/event_target.js
@@ -0,0 +1,79 @@
+/*
+ * vim: ts=4:sw=4:expandtab
+ *
+ * Implements EventTarget
+ * https://developer.mozilla.org/en-US/docs/Web/API/EventTarget
+ *
+ */
+
+;(function () {
+    'use strict';
+    window.textsecure = window.textsecure || {};
+
+    function EventTarget() {
+    }
+
+    EventTarget.prototype = {
+        constructor: EventTarget,
+        dispatchEvent: function(ev) {
+            if (!(ev instanceof Event)) {
+                throw new Error('Expects an event');
+            }
+            if (this.listeners === null || typeof this.listeners !== 'object') {
+                this.listeners = {};
+            }
+            var listeners = this.listeners[ev.type];
+            if (typeof listeners === 'object') {
+                for (var i=0; i < listeners.length; ++i) {
+                    if (typeof listeners[i] === 'function') {
+                        listeners[i].call(null, ev);
+                    }
+                }
+            }
+        },
+        addEventListener: function(eventName, callback) {
+            if (typeof eventName !== 'string') {
+                throw new Error('First argument expects a string');
+            }
+            if (typeof callback !== 'function') {
+                throw new Error('Second argument expects a function');
+            }
+            if (this.listeners === null || typeof this.listeners !== 'object') {
+                this.listeners = {};
+            }
+            var listeners = this.listeners[eventName];
+            if (typeof listeners !== 'object') {
+                listeners = [];
+            }
+            listeners.push(callback);
+            this.listeners[eventName] = listeners;
+        },
+        removeEventListener: function(eventName, callback) {
+            if (typeof eventName !== 'string') {
+                throw new Error('First argument expects a string');
+            }
+            if (typeof callback !== 'function') {
+                throw new Error('Second argument expects a function');
+            }
+            if (this.listeners === null || typeof this.listeners !== 'object') {
+                this.listeners = {};
+            }
+            var listeners = this.listeners[eventName];
+            for (var i=0; i < listeners.length; ++ i) {
+                if (listeners[i] === callback) {
+                    listeners.splice(i, 1);
+                    return;
+                }
+            }
+            this.listeners[eventName] = listeners;
+        },
+        extend: function(obj) {
+          for (var prop in obj) {
+            this[prop] = obj[prop];
+          }
+          return this;
+        }
+    };
+
+    textsecure.EventTarget = EventTarget;
+}());
diff --git a/libtextsecure/message_receiver.js b/libtextsecure/message_receiver.js
index f17a79001..f2612b140 100644
--- a/libtextsecure/message_receiver.js
+++ b/libtextsecure/message_receiver.js
@@ -13,7 +13,9 @@ function MessageReceiver(url, username, password, signalingKey, attachment_serve
     this.number = unencoded[0];
     this.deviceId = unencoded[1];
 }
-MessageReceiver.prototype = {
+
+MessageReceiver.prototype = new textsecure.EventTarget();
+MessageReceiver.prototype.extend({
     constructor: MessageReceiver,
     connect: function() {
         if (this.socket && this.socket.readyState !== WebSocket.CLOSED) {
@@ -371,63 +373,8 @@ MessageReceiver.prototype = {
         return Promise.all(promises).then(function() {
             return decrypted;
         });
-    },
-
-    /* Implements EventTarget */
-    dispatchEvent: function(ev) {
-        if (!(ev instanceof Event)) {
-            throw new Error('Expects an event');
-        }
-        if (this.listeners === null || typeof this.listeners !== 'object') {
-            this.listeners = {};
-        }
-        var listeners = this.listeners[ev.type];
-        if (typeof listeners === 'object') {
-            for (var i=0; i < listeners.length; ++i) {
-                if (typeof listeners[i] === 'function') {
-                    listeners[i].call(null, ev);
-                }
-            }
-        }
-    },
-    addEventListener: function(eventName, callback) {
-        if (typeof eventName !== 'string') {
-            throw new Error('First argument expects a string');
-        }
-        if (typeof callback !== 'function') {
-            throw new Error('Second argument expects a function');
-        }
-        if (this.listeners === null || typeof this.listeners !== 'object') {
-            this.listeners = {};
-        }
-        var listeners = this.listeners[eventName];
-        if (typeof listeners !== 'object') {
-            listeners = [];
-        }
-        listeners.push(callback);
-        this.listeners[eventName] = listeners;
-    },
-    removeEventListener: function(eventName, callback) {
-        if (typeof eventName !== 'string') {
-            throw new Error('First argument expects a string');
-        }
-        if (typeof callback !== 'function') {
-            throw new Error('Second argument expects a function');
-        }
-        if (this.listeners === null || typeof this.listeners !== 'object') {
-            this.listeners = {};
-        }
-        var listeners = this.listeners[eventName];
-        for (var i=0; i < listeners.length; ++ i) {
-            if (listeners[i] === callback) {
-                listeners.splice(i, 1);
-                return;
-            }
-        }
-        this.listeners[eventName] = listeners;
     }
-
-};
+});
 
 window.textsecure = window.textsecure || {};
 
diff --git a/libtextsecure/sync_request.js b/libtextsecure/sync_request.js
index 240eadac0..3d81039b9 100644
--- a/libtextsecure/sync_request.js
+++ b/libtextsecure/sync_request.js
@@ -19,10 +19,11 @@
         sender.sendRequestContactSyncMessage().then(function() {
             sender.sendRequestGroupSyncMessage();
         });
-        this.timeout = setTimout(this.onTimeout.bind(this), 60000);
+        this.timeout = setTimeout(this.onTimeout.bind(this), 60000);
     }
 
-    SyncRequest.prototype = {
+    SyncRequest.prototype = new textsecure.EventTarget();
+    SyncRequest.prototype.extend({
         constructor: SyncRequest,
         onContactSyncComplete: function() {
             this.contactSync = true;
@@ -47,62 +48,8 @@
             this.receiver.removeEventListener('contactsync', this.oncontact);
             this.receiver.removeEventListener('groupSync', this.ongroup);
             delete this.listeners;
-        },
-
-        /* Implements EventTarget */  /// TODO: Dedupe this same code in MessageReceiver
-        dispatchEvent: function(ev) {
-            if (!(ev instanceof Event)) {
-                throw new Error('Expects an event');
-            }
-            if (this.listeners === null || typeof this.listeners !== 'object') {
-                this.listeners = {};
-            }
-            var listeners = this.listeners[ev.type];
-            if (typeof listeners === 'object') {
-                for (var i=0; i < listeners.length; ++i) {
-                    if (typeof listeners[i] === 'function') {
-                        listeners[i].call(null, ev);
-                    }
-                }
-            }
-        },
-        addEventListener: function(eventName, callback) {
-            if (typeof eventName !== 'string') {
-                throw new Error('First argument expects a string');
-            }
-            if (typeof callback !== 'function') {
-                throw new Error('Second argument expects a function');
-            }
-            if (this.listeners === null || typeof this.listeners !== 'object') {
-                this.listeners = {};
-            }
-            var listeners = this.listeners[eventName];
-            if (typeof listeners !== 'object') {
-                listeners = [];
-            }
-            listeners.push(callback);
-            this.listeners[eventName] = listeners;
-        },
-        removeEventListener: function(eventName, callback) {
-            if (typeof eventName !== 'string') {
-                throw new Error('First argument expects a string');
-            }
-            if (typeof callback !== 'function') {
-                throw new Error('Second argument expects a function');
-            }
-            if (this.listeners === null || typeof this.listeners !== 'object') {
-                this.listeners = {};
-            }
-            var listeners = this.listeners[eventName];
-            for (var i=0; i < listeners.length; ++ i) {
-                if (listeners[i] === callback) {
-                    listeners.splice(i, 1);
-                    return;
-                }
-            }
-            this.listeners[eventName] = listeners;
         }
-    };
+    });
 
     textsecure.SyncRequest = function(sender, receiver) {
         var syncRequest = new SyncRequest(sender, receiver);