feat(chat): extract shared stream-engine helpers

surfsense_web/lib/chat/stream-engine/helpers.ts

@@ -0,0 +1,154 @@
+import { z } from "zod";
+import type { MentionedDocumentInfo } from "@/atoms/chat/mentioned-documents.atom";
+import type { ToolUIGate } from "@/lib/chat/streaming-state";
+
+/**
+ * Every tool call renders a card. The sentinel ``"all"`` matches every tool
+ * — the legacy ``BASE_TOOLS_WITH_UI`` allowlist was dropped so unknown tool
+ * calls route through the generic ``ToolFallback``. Persisted payload size
+ * stays bounded because the backend's ``format_thinking_step`` summarisation
+ * and the ``result_length``-only default for unknown tools keep the JSON
+ * from ballooning.
+ */
+export const TOOLS_WITH_UI_ALL: ToolUIGate = "all";
+
+export const TURN_CANCELLING_INITIAL_DELAY_MS = 200;
+export const TURN_CANCELLING_BACKOFF_FACTOR = 2;
+export const TURN_CANCELLING_MAX_DELAY_MS = 1500;
+export const RECENT_CANCEL_WINDOW_MS = 5_000;
+
+export function sleep(ms: number): Promise<void> {
+	return new Promise((resolve) => setTimeout(resolve, ms));
+}
+
+export function computeFallbackTurnCancellingRetryDelay(attempt: number): number {
+	const safeAttempt = Math.max(1, attempt);
+	const raw =
+		TURN_CANCELLING_INITIAL_DELAY_MS * TURN_CANCELLING_BACKOFF_FACTOR ** (safeAttempt - 1);
+	return Math.min(raw, TURN_CANCELLING_MAX_DELAY_MS);
+}
+
+/**
+ * Generate a synthetic ``toolCallId`` for an action_request that has no
+ * matching streamed tool-call card (HITL-blocked subagent calls don't surface
+ * as tool-call events). Suffixes a counter when the base id is already taken
+ * — sequential interrupts for the same tool name otherwise collide on
+ * ``interrupt-${name}-${i}`` and crash assistant-ui with a duplicate-key error.
+ */
+export function freshSynthToolCallId(
+	toolCallIndices: Map<string, number>,
+	toolName: string,
+	index: number
+): string {
+	const base = `interrupt-${toolName}-${index}`;
+	if (!toolCallIndices.has(base)) return base;
+	let n = 1;
+	while (toolCallIndices.has(`${base}-${n}`)) n++;
+	return `${base}-${n}`;
+}
+
+/**
+ * Pair each ``action_request`` to a unique pending tool-call card, preserving
+ * order so ``decisions[i]`` lines up with ``action_requests[i]`` on the wire.
+ *
+ * Same-name bundles (e.g. three ``create_jira_issue``) used to collapse onto
+ * one card because the matcher keyed by name; this consumes each card via the
+ * ``claimed`` set and walks forward in DOM order.
+ */
+export function pairBundleToolCallIds(
+	toolCallIndices: Map<string, number>,
+	contentParts: Array<{
+		type: string;
+		toolName?: string;
+		result?: unknown;
+	}>,
+	actionRequests: ReadonlyArray<{ name: string }>
+): Array<string | null> {
+	const claimed = new Set<string>();
+	const paired: Array<string | null> = [];
+	for (const action of actionRequests) {
+		let matched: string | null = null;
+		for (const [tcId, idx] of toolCallIndices) {
+			if (claimed.has(tcId)) continue;
+			const part = contentParts[idx];
+			if (!part || part.type !== "tool-call" || part.toolName !== action.name) continue;
+			const result = part.result as Record<string, unknown> | undefined | null;
+			if (result == null || (result.__interrupt__ === true && !result.__decided__)) {
+				matched = tcId;
+				claimed.add(tcId);
+				break;
+			}
+		}
+		paired.push(matched);
+	}
+	return paired;
+}
+
+/**
+ * Zod schema for mentioned document info (for type-safe parsing).
+ *
+ * ``kind`` defaults to ``"doc"`` so messages persisted before folder
+ * mentions existed deserialise unchanged.
+ */
+const MentionedDocumentInfoSchema = z.object({
+	id: z.number(),
+	title: z.string(),
+	document_type: z.string().optional(),
+	kind: z
+		.union([z.literal("doc"), z.literal("folder"), z.literal("connector"), z.literal("thread")])
+		.optional()
+		.default("doc"),
+	connector_type: z.string().optional(),
+	account_name: z.string().optional(),
+});
+
+const MentionedDocumentsPartSchema = z.object({
+	type: z.literal("mentioned-documents"),
+	documents: z.array(MentionedDocumentInfoSchema),
+});
+
+/**
+ * Extract mentioned documents from message content (type-safe with Zod).
+ */
+export function extractMentionedDocuments(content: unknown): MentionedDocumentInfo[] {
+	if (!Array.isArray(content)) return [];
+
+	for (const part of content) {
+		const result = MentionedDocumentsPartSchema.safeParse(part);
+		if (result.success) {
+			return result.data.documents.map<MentionedDocumentInfo>((doc) => {
+				if (doc.kind === "connector") {
+					return {
+						id: doc.id,
+						title: doc.title,
+						kind: "connector",
+						connector_type: doc.connector_type ?? doc.document_type ?? "UNKNOWN",
+						account_name: doc.account_name ?? doc.title,
+					};
+				}
+				if (doc.kind === "folder") {
+					return {
+						id: doc.id,
+						title: doc.title,
+						kind: "folder",
+					};
+				}
+				if (doc.kind === "thread") {
+					return {
+						id: doc.id,
+						title: doc.title,
+						kind: "thread",
+					};
+				}
+				return {
+					id: doc.id,
+					title: doc.title,
+					document_type: doc.document_type ?? "UNKNOWN",
+					kind: "doc",
+				};
+			});
+		}
+	}
+
+	return [];
+}