Main logic implemented

.tool-versions

@@ -0,0 +1,2 @@
+nodejs 22.14.0
+pnpm 8.15.4

injected.js

@@ -1,8 +1,12 @@
+const EMOJI_TARGET = "❤"; // Acting like ❤️ on Whatsapp
+
 (function () {
 	console.log("WhatsApp Heart Favorites script - Candidate Test");
 
 	// Initialize WhatsApp Store access
 	function initializeWAStore() {
+		window.Store = null;
+
 		// Wait for WhatsApp to initialize its modules
 		const storeCheckInterval = setInterval(() => {
 			if (window.Store) {
@@ -14,6 +18,10 @@
 
 			if (typeof window.require === "function") {
 				try {
+					if (!window.require("WAWebCollections").Reactions._models?.length) {
+						console.log("Not injected. Still not defined");
+						return;
+					}
 					// Load the essential modules
 					window.Store = Object.assign({}, window.require("WAWebCollections"));
 					window.Store.Cmd = window.require("WAWebCmd").Cmd;
@@ -30,9 +38,8 @@
 
 	// Set up listeners for heart reactions
 	function setupReactionListener() {
-    // TODO: Implement the reaction listener here
 		//
-    // CANDIDATE TASK: Write code that will star a message when you react to it with a heart emoji
+		// CANDIDATE TASK: Write code that will star a message when you react to it with a heart emoji ✅
 		//
 		// Hints:
 		// 1. You'll need to listen for reaction events using Store.Reactions
@@ -48,7 +55,27 @@
 		// require("WAWebCmd") or any other module name. This will show you available methods,
 		// _events, and other properties that might be helpful for this task.
 
-    console.log("Reaction listener needs to be implemented");
+		Store.Reactions._models.forEach((model) => {
+			model.reactions._events.add = [
+				...model.reactions._events.add,
+				{
+					callback: async (...args) => {
+						if (args[0].__x_aggregateEmoji === EMOJI_TARGET) {
+							const msgKey = args[1].parent.__x_id._serialized;
+							const msg = Store.Msg.get(msgKey);
+							const chat = await Store.Chat.find(msg.id.remote);
+							const messageHasStar = msg.__x_star;
+
+							if (!messageHasStar) {
+								Store.Cmd.sendStarMsgs(chat, [msg], false);
+							} else {
+								Store.Cmd.sendUnstarMsgs(chat, [msg], false);
+							}
+						}
+					},
+				},
+			];
+		});
 	}
 
 	// Initialize