1/**
2 * The subagent roster for one turn, and the compact label the mobile composer
3 * pill renders for it.
4 *
5 * Scoped to a run rather than the whole thread: a thread accumulates every
6 * subagent it ever spawned, while the pill and its sheet answer "what is this
7 * turn doing right now". Statuses come from the v2 projection directly, so
8 * this stays a pure fold over `runs` and `subagents`.
9 */
10import * as DateTime from "effect/DateTime";
11import type { OrchestrationV2Subagent, OrchestrationV2ThreadProjection } from "@t3tools/contracts";
12import { copySorted } from "@t3tools/shared/Array";
13
14import { isActiveSubagentStatus, isTerminalSubagentStatus } from "./subagentRuntime.ts";
15import { resolveActiveThreadRun } from "./threadWorkflows.ts";
16
17type Projection = OrchestrationV2ThreadProjection;
18type Subagent = OrchestrationV2Subagent;
19type RunId = Projection["runs"][number]["id"];
20
21export interface ThreadTurnSubagents {
22 /** The run the roster belongs to: the active one, else the most recent one that spawned agents. */
23 readonly runId: RunId | null;
24 readonly turnActive: boolean;
25 /** Spawn order: startedAt, falling back to updatedAt for agents that never started. */
26 readonly subagents: ReadonlyArray<Subagent>;
27 readonly liveCount: number;
28 readonly settledCount: number;
29}
30
31export interface SubagentPillSegment {
32 readonly label: string;
33 readonly accessibilityLabel: string;
34}
35
36function orderKey(subagent: Subagent): number {
37 return DateTime.toEpochMillis(subagent.startedAt ?? subagent.updatedAt);
38}
39
40/** null when the thread has never spawned a subagent. */
41export function deriveThreadTurnSubagents(
42 projection: Pick<Projection, "runs" | "subagents">,
43): ThreadTurnSubagents | null {
44 if (projection.subagents.length === 0) return null;
45 const activeRun = resolveActiveThreadRun(projection);
46 // With no live run the newest roster is still worth showing: a turn that
47 // just finished leaves results the user has not read yet.
48 const latestUpdated = projection.subagents.reduce((latest, subagent) =>
49 DateTime.toEpochMillis(subagent.updatedAt) > DateTime.toEpochMillis(latest.updatedAt)
50 ? subagent
51 : latest,
52 );
53 const runId = activeRun?.id ?? latestUpdated.runId;
54 const subagents = copySorted(
55 projection.subagents.filter((subagent) => subagent.runId === runId),
56 (left, right) => orderKey(left) - orderKey(right) || left.id.localeCompare(right.id),
57 );
58 if (subagents.length === 0) return null;
59
60 let liveCount = 0;
61 let settledCount = 0;
62 for (const subagent of subagents) {
63 if (isActiveSubagentStatus(subagent.status)) liveCount += 1;
64 else if (isTerminalSubagentStatus(subagent.status)) settledCount += 1;
65 }
66 return { runId, turnActive: activeRun !== null, subagents, liveCount, settledCount };
67}
68
69/**
70 * What the pill's agents segment says, or null while it should stay hidden.
71 * The segment is for work in flight: once the turn settles it goes away
72 * rather than leaving a stale count above the composer.
73 */
74export function resolveSubagentPillSegment(
75 turn: ThreadTurnSubagents | null,
76): SubagentPillSegment | null {
77 if (turn === null) return null;
78 if (!turn.turnActive && turn.liveCount === 0) return null;
79 const total = turn.subagents.length;
80 if (turn.liveCount > 0) {
81 return {
82 label: `${turn.liveCount}/${total}`,
83 accessibilityLabel: `${turn.liveCount} of ${total} agents working`,
84 };
85 }
86 return {
87 label: `${total} done`,
88 accessibilityLabel: `${total} ${total === 1 ? "agent" : "agents"} done`,
89 };
90}