| 1 | import type { TabMeta } from "./types"; |
| 2 | |
| 3 | export function activeLeaseBlockedTab(tabMetas: TabMeta[], activeTabId: string | null | undefined): TabMeta | undefined { |
| 4 | if (!activeTabId) return undefined; |
| 5 | const active = tabMetas.find((tab) => tab.id === activeTabId); |
| 6 | return active && !active.remote && active.runtime?.issue?.code === "session_lease_held" ? active : undefined; |
| 7 | } |
| 8 | |
| 9 | export function seedActiveTabMetaList(current: TabMeta[], tab: TabMeta): TabMeta[] { |
| 10 | const seeded = { ...tab, historicalSource: tab.historicalSource, active: true }; |
| 11 | let found = false; |
| 12 | const next = current.map((existing) => { |
| 13 | if (existing.id === tab.id) { |
| 14 | found = true; |
| 15 | return { ...existing, ...seeded }; |
| 16 | } |
| 17 | return existing.active ? { ...existing, active: false } : existing; |
| 18 | }); |
| 19 | return found ? next : [...next, seeded]; |
| 20 | } |
| 21 | |
| 22 | export const TAB_META_VISIBLE_FALLBACK_MS = 15_000; |
| 23 | export const TAB_META_HIDDEN_FALLBACK_MS = 60_000; |
| 24 | export const TAB_META_MAX_IN_FLIGHT = 2; |
| 25 | |
| 26 | export type BoundedRefreshResult<T> = { |
| 27 | value: T; |
| 28 | latest: boolean; |
| 29 | coalesced: boolean; |
| 30 | }; |
| 31 | |
| 32 | export type BoundedRefreshOptions = { |
| 33 | /** |
| 34 | * Mutation-sensitive refresh: never treat a pre-mutation in-flight request |
| 35 | * as authoritative. When saturated, queue a trailing load that starts after |
| 36 | * a slot frees instead of applying the joined pre-mutation snapshot. |
| 37 | */ |
| 38 | invalidate?: boolean; |
| 39 | }; |
| 40 | |
| 41 | export function createBoundedRefreshCoordinator<T>(maxInFlight: number) { |
| 42 | if (!Number.isInteger(maxInFlight) || maxInFlight < 1) { |
| 43 | throw new Error("maxInFlight must be a positive integer"); |
| 44 | } |
| 45 | let sequence = 0; |
| 46 | let generation = 0; |
| 47 | const inFlight: Array<{ sequence: number; generation: number; promise: Promise<T> }> = []; |
| 48 | let trailing: { |
| 49 | load: () => Promise<T>; |
| 50 | waiters: Array<{ |
| 51 | resolve: (result: BoundedRefreshResult<T>) => void; |
| 52 | reject: (reason?: unknown) => void; |
| 53 | }>; |
| 54 | } | null = null; |
| 55 | |
| 56 | const settleEntry = (entry: { sequence: number; generation: number; promise: Promise<T> }) => { |
| 57 | const index = inFlight.indexOf(entry); |
| 58 | if (index >= 0) inFlight.splice(index, 1); |
| 59 | pumpTrailing(); |
| 60 | }; |
| 61 | |
| 62 | const startEntry = (load: () => Promise<T>) => { |
| 63 | const entry = { |
| 64 | sequence: ++sequence, |
| 65 | generation, |
| 66 | promise: Promise.resolve().then(load), |
| 67 | }; |
| 68 | inFlight.push(entry); |
| 69 | void entry.promise.then( |
| 70 | () => settleEntry(entry), |
| 71 | () => settleEntry(entry), |
| 72 | ); |
| 73 | return entry; |
| 74 | }; |
| 75 | |
| 76 | const resultFor = ( |
| 77 | entry: { sequence: number; generation: number }, |
| 78 | value: T, |
| 79 | coalesced: boolean, |
| 80 | ): BoundedRefreshResult<T> => ({ |
| 81 | value, |
| 82 | latest: entry.sequence === sequence && entry.generation === generation, |
| 83 | coalesced, |
| 84 | }); |
| 85 | |
| 86 | const queueTrailing = (load: () => Promise<T>): Promise<BoundedRefreshResult<T>> => { |
| 87 | if (!trailing) { |
| 88 | trailing = { load, waiters: [] }; |
| 89 | } else { |
| 90 | trailing.load = load; |
| 91 | } |
| 92 | return new Promise<BoundedRefreshResult<T>>((resolve, reject) => { |
| 93 | trailing!.waiters.push({ resolve, reject }); |
| 94 | pumpTrailing(); |
| 95 | }); |
| 96 | }; |
| 97 | |
| 98 | function pumpTrailing() { |
| 99 | if (!trailing || inFlight.length >= maxInFlight) return; |
| 100 | const job = trailing; |
| 101 | trailing = null; |
| 102 | const entry = startEntry(job.load); |
| 103 | void entry.promise.then( |
| 104 | (value) => { |
| 105 | const result = resultFor(entry, value, false); |
| 106 | for (const waiter of job.waiters) waiter.resolve(result); |
| 107 | }, |
| 108 | (reason) => { |
| 109 | for (const waiter of job.waiters) waiter.reject(reason); |
| 110 | }, |
| 111 | ); |
| 112 | } |
| 113 | |
| 114 | return { |
| 115 | run(load: () => Promise<T>, options?: BoundedRefreshOptions): Promise<BoundedRefreshResult<T>> { |
| 116 | if (options?.invalidate) { |
| 117 | generation += 1; |
| 118 | // Mutation-sensitive callers must not join a pre-mutation request. |
| 119 | if (inFlight.length >= maxInFlight) { |
| 120 | return queueTrailing(load); |
| 121 | } |
| 122 | const entry = startEntry(load); |
| 123 | return entry.promise.then((value) => resultFor(entry, value, false)); |
| 124 | } |
| 125 | |
| 126 | let entry = inFlight.length >= maxInFlight ? inFlight[inFlight.length - 1] : undefined; |
| 127 | const coalesced = entry !== undefined; |
| 128 | if (!entry) { |
| 129 | entry = startEntry(load); |
| 130 | } |
| 131 | const selected = entry; |
| 132 | return selected.promise.then((value) => resultFor(selected, value, coalesced)); |
| 133 | }, |
| 134 | }; |
| 135 | } |
| 136 | |
| 137 | const TAB_META_EVENT_KINDS = new Set([ |
| 138 | "turn_started", |
| 139 | "turn_done", |
| 140 | "retrying", |
| 141 | "approval_request", |
| 142 | "ask_request", |
| 143 | ]); |
| 144 | |
| 145 | export function tabMetaFallbackDelay(visibility: DocumentVisibilityState): number { |
| 146 | return visibility === "hidden" ? TAB_META_HIDDEN_FALLBACK_MS : TAB_META_VISIBLE_FALLBACK_MS; |
| 147 | } |
| 148 | |
| 149 | export function shouldRefreshTabMetaForEvent(kind: string): boolean { |
| 150 | return TAB_META_EVENT_KINDS.has(kind); |
| 151 | } |
| 152 | |
| 153 | export function sameTabMetaLists(current: readonly TabMeta[], next: readonly TabMeta[]): boolean { |
| 154 | if (current === next) return true; |
| 155 | if (current.length !== next.length) return false; |
| 156 | for (let index = 0; index < current.length; index += 1) { |
| 157 | if (JSON.stringify(current[index]) !== JSON.stringify(next[index])) return false; |
| 158 | } |
| 159 | return true; |
| 160 | } |
| 161 |