Allow plugins to inject HTML into notifications before they're shown

Closes #112

Core/Notification/FormNotificationBase.cs

@@ -164,12 +164,15 @@ public virtual void ResumeNotification(){
             }
         }
 
+        protected virtual string GetTweetHTML(TweetNotification tweet){
+            string bodyClasses = browser.Bounds.Contains(PointToClient(Cursor.Position)) ? "td-hover" : string.Empty;
+            return tweet.GenerateHtml(bodyClasses);
+        }
+
         protected virtual void LoadTweet(TweetNotification tweet){
             CurrentUrl = tweet.Url;
             CurrentQuotedTweetUrl = string.Empty; // load from JS
-
-            string bodyClasses = browser.Bounds.Contains(PointToClient(Cursor.Position)) ? "td-hover" : string.Empty;
-            browser.LoadHtml(tweet.GenerateHtml(bodyClasses), "http://tweetdeck.twitter.com/?"+DateTime.Now.Ticks);
+            browser.LoadHtml(GetTweetHTML(tweet), "http://tweetdeck.twitter.com/?"+DateTime.Now.Ticks);
         }
 
         protected virtual void SetNotificationSize(int width, int height){

Core/Notification/FormNotificationMain.cs

@@ -200,6 +200,16 @@ public override void ResumeNotification(){
             }
         }
 
+        protected override string GetTweetHTML(TweetNotification tweet){
+            string html = base.GetTweetHTML(tweet);
+
+            foreach(InjectedHTML injection in plugins.Bridge.NotificationInjections){
+                html = injection.Inject(html);
+            }
+
+            return html;
+        }
+
         protected override void LoadTweet(TweetNotification tweet){
             timerProgress.Stop();
             totalTime = timeLeft = tweet.GetDisplayDuration(Program.UserConfig.NotificationDurationValue);

Plugins/PluginBridge.cs

@@ -1,4 +1,5 @@
 using System;
+using System.Collections.Generic;
 using System.IO;
 using System.Text;
 using TweetDck.Core.Utils;
@@ -13,6 +14,13 @@ private static string SanitizeCacheKey(string key){
 
         private readonly PluginManager manager;
         private readonly TwoKeyDictionary<int, string, string> fileCache = new TwoKeyDictionary<int, string, string>(4, 2);
+        private readonly TwoKeyDictionary<int, string, InjectedHTML> notificationInjections = new TwoKeyDictionary<int,string,InjectedHTML>(4, 1);
+
+        public IEnumerable<InjectedHTML> NotificationInjections{
+            get{
+                return notificationInjections.InnerValues;
+            }
+        }
 
         public PluginBridge(PluginManager manager){
             this.manager = manager;
@@ -20,16 +28,23 @@ public PluginBridge(PluginManager manager){
             this.manager.PluginChangedState += manager_PluginChangedState;
         }
 
+        // Event handlers
+
         private void manager_Reloaded(object sender, PluginErrorEventArgs e){
             fileCache.Clear();
         }
 
         private void manager_PluginChangedState(object sender, PluginChangedStateEventArgs e){
             if (!e.IsEnabled){
-                fileCache.Remove(manager.GetTokenFromPlugin(e.Plugin));
+                int token = manager.GetTokenFromPlugin(e.Plugin);
+
+                fileCache.Remove(token);
+                notificationInjections.Remove(token);
             }
         }
 
+        // Utility methods
+
         private string GetFullPathOrThrow(int token, PluginFolder folder, string path){
             Plugin plugin = manager.GetPluginFromToken(token);
             string fullPath = plugin == null ? string.Empty : plugin.GetFullPathIfSafe(folder, path);
@@ -98,5 +113,13 @@ public string ReadFileRoot(int token, string path){
         public bool CheckFileExistsRoot(int token, string path){
             return File.Exists(GetFullPathOrThrow(token, PluginFolder.Root, path));
         }
+
+        public void InjectIntoNotificationsBefore(int token, string key, string search, string html){
+            notificationInjections[token, key] = new InjectedHTML(InjectedHTML.Position.Before, search, html);
+        }
+
+        public void InjectIntoNotificationsAfter(int token, string key, string search, string html){
+            notificationInjections[token, key] = new InjectedHTML(InjectedHTML.Position.After, search, html);
+        }
     }
 }