1 files changed, 92 insertions, 0 deletions
diff --git a/webapp/stores/reaction_store.jsx b/webapp/stores/reaction_store.jsx
new file mode 100644
index 000000000..166569e3d
--- /dev/null
+++ b/webapp/stores/reaction_store.jsx
@@ -0,0 +1,92 @@
+// Copyright (c) 2016 Mattermost, Inc. All Rights Reserved.
+// See License.txt for license information.
+
+import AppDispatcher from '../dispatcher/app_dispatcher.jsx';
+import Constants from 'utils/constants.jsx';
+import EventEmitter from 'events';
+
+const ActionTypes = Constants.ActionTypes;
+
+const CHANGE_EVENT = 'changed';
+
+class ReactionStore extends EventEmitter {
+    constructor() {
+        super();
+
+        this.dispatchToken = AppDispatcher.register(this.handleEventPayload.bind(this));
+
+        this.reactions = new Map();
+
+        this.setMaxListeners(600);
+    }
+
+    addChangeListener(postId, callback) {
+        this.on(CHANGE_EVENT + postId, callback);
+    }
+
+    removeChangeListener(postId, callback) {
+        this.removeListener(CHANGE_EVENT + postId, callback);
+    }
+
+    emitChange(postId) {
+        this.emit(CHANGE_EVENT + postId, postId);
+    }
+
+    setReactions(postId, reactions) {
+        this.reactions.set(postId, reactions);
+    }
+
+    addReaction(postId, reaction) {
+        const reactions = [];
+
+        for (const existing of this.getReactions(postId)) {
+            // make sure not to add duplicates
+            if (existing.user_id !== reaction.user_id || existing.post_id !== reaction.post_id ||
+                existing.emoji_name !== reaction.emoji_name) {
+                reactions.push(existing);
+            }
+        }
+
+        reactions.push(reaction);
+
+        this.setReactions(postId, reactions);
+    }
+
+    removeReaction(postId, reaction) {
+        const reactions = [];
+
+        for (const existing of this.getReactions(postId)) {
+            if (existing.user_id !== reaction.user_id || existing.post_id !== reaction.post_id ||
+                existing.emoji_name !== reaction.emoji_name) {
+                reactions.push(existing);
+            }
+        }
+
+        this.setReactions(postId, reactions);
+    }
+
+    getReactions(postId) {
+        return this.reactions.get(postId) || [];
+    }
+
+    handleEventPayload(payload) {
+        const action = payload.action;
+
+        switch (action.type) {
+        case ActionTypes.RECEIVED_REACTIONS:
+            this.setReactions(action.postId, action.reactions);
+            this.emitChange(action.postId);
+            break;
+        case ActionTypes.ADDED_REACTION:
+            this.addReaction(action.postId, action.reaction);
+            this.emitChange(action.postId);
+            break;
+        case ActionTypes.REMOVED_REACTION:
+            this.removeReaction(action.postId, action.reaction);
+            this.emitChange(action.postId);
+            break;
+        }
+    }
+}
+
+export default new ReactionStore();
+\ No newline at end of file