server/client: refactor command input

Keep happy path on the left and try to return as early
as we can to help the reader understand the logic better

The function is too large to be able to quickly scan an if / else
chain and see the function return at the end

server/client.ts

@@ -465,46 +465,54 @@ class Client {
 		const cmd = args?.shift()?.toLowerCase() || "";
 
 		const irc = target.network.irc;
-		let connected = irc && irc.connection && irc.connection.connected;
+		const connected = irc?.connected;
 
-		if (inputs.userInputs.has(cmd)) {
-			const plugin = inputs.userInputs.get(cmd);
-
-			if (!plugin) {
-				// should be a no-op
-				throw new Error(`Plugin ${cmd} not found`);
-			}
-
-			if (typeof plugin.input === "function" && (connected || plugin.allowDisconnected)) {
-				connected = true;
-				plugin.input.apply(client, [target.network, target.chan, cmd, args]);
-			}
-		} else if (inputs.pluginCommands.has(cmd)) {
-			const plugin = inputs.pluginCommands.get(cmd);
-
-			if (typeof plugin.input === "function" && (connected || plugin.allowDisconnected)) {
-				connected = true;
-				plugin.input(
-					new PublicClient(client, plugin.packageInfo),
-					{network: target.network, chan: target.chan},
-					cmd,
-					args
-				);
-			}
-		} else if (connected) {
-			// TODO: fix
-			irc!.raw(text);
-		}
-
-		if (!connected) {
+		const emitFailureDisconnected = () => {
 			target.chan.pushMessage(
 				this,
 				new Msg({
 					type: MessageType.ERROR,
 					text: "You are not connected to the IRC network, unable to send your command.",
 				})
 			);
+		};
+
+		const plugin = inputs.userInputs.get(cmd);
+
+		if (plugin) {
+			if (!connected && !plugin.allowDisconnected) {
+				emitFailureDisconnected();
+				return;
+			}
+
+			plugin.input.apply(client, [target.network, target.chan, cmd, args]);
+			return;
+		}
+
+		const extPlugin = inputs.pluginCommands.get(cmd);
+
+		if (extPlugin) {
+			if (!connected && !extPlugin.allowDisconnected) {
+				emitFailureDisconnected();
+				return;
+			}
+
+			extPlugin.input(
+				new PublicClient(client, extPlugin.packageInfo),
+				{network: target.network, chan: target.chan},
+				cmd,
+				args
+			);
+			return;
 		}
+
+		if (!connected) {
+			emitFailureDisconnected();
+			return;
+		}
+
+		// TODO: fix
+		irc!.raw(text);
 	}
 
 	compileCustomHighlights() {