refactor: Refactor message handlers into dedicated modules

src/main/web-server/handlers/messageHandlers/cadenza.ts

@@ -0,0 +1,108 @@
+/**
+ * Cadenza domain WebSocket message handlers.
+ *
+ * Extracted from WebSocketMessageHandler.ts. Handles: cadenza.
+ */
+
+import {
+	CADENZA_OPS,
+	CADENZA_VIEW_TYPES,
+	CADENZA_COLORS,
+	type CadenzaPayload,
+	type CadenzaOp,
+	type CadenzaViewType,
+	type CadenzaColor,
+} from '../../../../shared/cadenza-types';
+import type { WebClient, WebClientMessage, MessageHandlerContext } from './types';
+
+/**
+ * Handle cadenza - open/update/close a small agent-driven cadenza view.
+ * Validates the op/id/viewType/color, then hands a typed payload to the
+ * renderer via the cadenzaView callback (the `remote:cadenza` channel).
+ */
+export function handleCadenza(
+	ctx: MessageHandlerContext,
+	client: WebClient,
+	message: WebClientMessage
+): void {
+	const op = typeof message.op === 'string' ? (message.op as CadenzaOp) : undefined;
+	const id = typeof message.id === 'string' ? message.id : '';
+
+	const sendResult = (success: boolean, error?: string) => {
+		ctx.send(client, {
+			type: 'cadenza_result',
+			success,
+			error,
+			requestId: message.requestId,
+		});
+	};
+
+	if (!op || !CADENZA_OPS.includes(op)) {
+		sendResult(false, `Invalid or missing op. Must be one of: ${CADENZA_OPS.join(', ')}`);
+		return;
+	}
+	if (!id) {
+		sendResult(false, 'Missing cadenza id');
+		return;
+	}
+
+	let viewType: CadenzaViewType | undefined;
+	const rawViewType = typeof message.viewType === 'string' ? message.viewType : undefined;
+	if (rawViewType !== undefined) {
+		if (!CADENZA_VIEW_TYPES.includes(rawViewType as CadenzaViewType)) {
+			sendResult(
+				false,
+				`Invalid viewType: ${rawViewType}. Must be one of: ${CADENZA_VIEW_TYPES.join(', ')}`
+			);
+			return;
+		}
+		viewType = rawViewType as CadenzaViewType;
+	}
+	if (op === 'open' && !viewType) {
+		sendResult(false, `op 'open' requires a viewType (${CADENZA_VIEW_TYPES.join(' | ')})`);
+		return;
+	}
+
+	let color: CadenzaColor | undefined;
+	const rawColor = typeof message.color === 'string' ? message.color : undefined;
+	if (rawColor !== undefined) {
+		if (!CADENZA_COLORS.includes(rawColor as CadenzaColor)) {
+			sendResult(false, `Invalid color: ${rawColor}. Must be one of: ${CADENZA_COLORS.join(', ')}`);
+			return;
+		}
+		color = rawColor as CadenzaColor;
+	}
+
+	// Decision buttons: keep only well-formed { label, value } string pairs.
+	const options = Array.isArray(message.options)
+		? (message.options as unknown[]).filter(
+				(o): o is { label: string; value: string } =>
+					!!o &&
+					typeof o === 'object' &&
+					typeof (o as { label?: unknown }).label === 'string' &&
+					typeof (o as { value?: unknown }).value === 'string'
+			)
+		: undefined;
+
+	const payload: CadenzaPayload = {
+		op,
+		id,
+		viewType,
+		title: typeof message.title === 'string' ? message.title : undefined,
+		body: typeof message.body === 'string' ? message.body : undefined,
+		path: typeof message.path === 'string' ? message.path : undefined,
+		options: options && options.length > 0 ? options : undefined,
+		color,
+		sessionId: typeof message.sessionId === 'string' ? message.sessionId : undefined,
+	};
+
+	if (!ctx.callbacks.cadenzaView) {
+		sendResult(false, 'Cadenza views not configured');
+		return;
+	}
+
+	ctx.callbacks
+		.cadenzaView(payload)
+		.then((success) => sendResult(success, success ? undefined : 'Failed to update cadenza view'))
+		.catch((error) => sendResult(false, `Failed to update cadenza view: ${error.message}`));
+}