Rewrite detection of newly loaded messages

Closes #240

app/Resources/Tracker/bootstrap.js

@@ -64,9 +64,11 @@
 			let action = null;
 			
 			if (!DISCORD.hasMoreMessages()) {
+				console.debug("[DHT] Reached first message.");
 				action = SETTINGS.afterFirstMsg;
 			}
 			if (isNoAction(action) && !anyNewMessages) {
+				console.debug("[DHT] No new messages.");
 				action = SETTINGS.afterSavedMsg;
 			}
 			

app/Resources/Tracker/scripts/discord.js

@@ -28,46 +28,11 @@ class DISCORD {
 	 * Calls the provided function with a list of messages whenever the currently loaded messages change.
 	 */
 	static setupMessageCallback(callback) {
-		let skipsLeft = 0;
-		let waitForCleanup = false;
 		const previousMessages = new Set();
 		
-		const timer = window.setInterval(() => {
-			if (skipsLeft > 0) {
-				--skipsLeft;
-				return;
-			}
-			
-			const view = this.getMessageOuterElement();
-			
-			if (!view) {
-				skipsLeft = 2;
-				return;
-			}
-			
-			const anyMessage = DOM.queryReactClass("message", this.getMessageOuterElement());
-			const messageCount = anyMessage ? anyMessage.parentElement.children.length : 0;
-			
-			if (messageCount > 300) {
-				if (waitForCleanup) {
-					return;
-				}
-				
-				skipsLeft = 3;
-				waitForCleanup = true;
-				
-				window.setTimeout(() => {
-					const view = this.getMessageScrollerElement();
-					// noinspection JSUnusedGlobalSymbols
-					view.scrollTop = view.scrollHeight / 2;
-				}, 1);
-			}
-			else {
-				waitForCleanup = false;
-			}
-			
-			const messages = this.getMessages();
-			const hasChanged = messages.some(message => !previousMessages.has(message.id)) || !this.hasMoreMessages();
+		const onMessageElementsChanged = function() {
+			const messages = DISCORD.getMessages();
+			const hasChanged = messages.some(message => !previousMessages.has(message.id)) || !DISCORD.hasMoreMessages();
 			
 			if (!hasChanged) {
 				return;
@@ -79,24 +44,74 @@ class DISCORD {
 			}
 			
 			callback(messages);
-		}, 200);
+		};
 		
-		window.DHT_ON_UNLOAD.push(() => window.clearInterval(timer));
+		let debounceTimer;
+		
+		/**
+		 * Do not trigger the callback too often due to autoscrolling.
+		 */
+		const onMessageElementsChangedLater = function() {
+			window.clearTimeout(debounceTimer);
+			debounceTimer = window.setTimeout(onMessageElementsChanged, 200);
+		};
+		
+		const observer = new MutationObserver(function () {
+			onMessageElementsChangedLater();
+		});
+		
+		let skipsLeft = 0;
+		let observedElement = null;
+		
+		const observerTimer = window.setInterval(() => {
+			if (skipsLeft > 0) {
+				--skipsLeft;
+				return;
+			}
+			
+			const view = this.getMessageOuterElement();
+			
+			if (!view) {
+				skipsLeft = 1;
+				return;
+			}
+			
+			if (observedElement !== null && observedElement.isConnected) {
+				return;
+			}
+			
+			observedElement = view.querySelector("[data-list-id='chat-messages']");
+			
+			if (observedElement) {
+				console.debug("[DHT] Observed message container.");
+				observer.observe(observedElement, { childList: true });
+				onMessageElementsChangedLater();
+			}
+		}, 400);
+		
+		window.DHT_ON_UNLOAD.push(() => {
+			observer.disconnect();
+			observedElement = null;
+			window.clearInterval(observerTimer);
+		});
 	}
 	
 	/**
-	 * Returns the property object of a message element.
-	 * @returns { null | { message: DiscordMessage, channel: Object } }
+	 * Returns the message from a message element.
+	 * @returns { null | DiscordMessage } }
 	 */
-	static getMessageElementProps(ele) {
+	static getMessageFromElement(ele) {
 		const props = DOM.getReactProps(ele);
 		
-		if (props.children && props.children.length) {
-			for (let i = 3; i < props.children.length; i++) {
-				const childProps = props.children[i].props;
+		if (props && Array.isArray(props.children)) {
+			for (const child of props.children) {
+				if (!(child instanceof Object)) {
+					continue;
+				}
 				
-				if (childProps && "message" in childProps && "channel" in childProps) {
-					return childProps;
+				const childProps = child.props;
+				if (childProps instanceof Object && "message" in childProps) {
+					return childProps.message;
 				}
 			}
 		}
@@ -113,10 +128,10 @@ class DISCORD {
 			
 			for (const ele of this.getMessageElements()) {
 				try {
-					const props = this.getMessageElementProps(ele);
+					const message = this.getMessageFromElement(ele);
 					
-					if (props != null) {
-						messages.push(props.message);
+					if (message != null) {
+						messages.push(message);
 					}
 				} catch (e) {
 					console.error("[DHT] Error extracing message data, skipping it.", e, ele, DOM.tryGetReactProps(ele));
@@ -137,7 +152,7 @@ class DISCORD {
 	 */
 	static getSelectedChannel() {
 		try {
-			let obj;
+			let obj = null;
 			
 			try {
 				for (const child of DOM.getReactProps(DOM.queryReactClass("chatContent")).children) {
@@ -148,15 +163,6 @@ class DISCORD {
 				}
 			} catch (e) {
 				console.error("[DHT] Error retrieving selected channel from 'chatContent' element.", e);
-				
-				for (const ele of this.getMessageElements()) {
-					const props = this.getMessageElementProps(ele);
-					
-					if (props != null) {
-						obj = props.channel;
-						break;
-					}
-				}
 			}
 			
 			if (!obj || typeof obj.id !== "string") {

app/Server/Server.csproj

@@ -11,7 +11,7 @@
   </ItemGroup>
   
   <ItemGroup>
-    <PackageReference Include="Microsoft.Data.Sqlite" Version="7.0.9" />
+    <PackageReference Include="Microsoft.Data.Sqlite" Version="8.0.0" />
   </ItemGroup>
   
   <ItemGroup>