import * as Arr from "effect/Array";import type { OrchestrationShellSnapshot, OrchestrationShellStreamEvent } from "@t3tools/contracts"; /** * Reduce a single shell stream event into an existing snapshot, returning a new * snapshot with the event's changes applied. This is a pure reducer that both * web and mobile can use to keep their local shell snapshot in sync. * * Returns the original snapshot reference unchanged if the event is not * recognized (forward-compatible). */export function applyShellStreamEvent(  snapshot: OrchestrationShellSnapshot,  event: OrchestrationShellStreamEvent,): OrchestrationShellSnapshot {  if (event.sequence <= snapshot.snapshotSequence) return snapshot;   switch (event.kind) {    case "project-upserted": {      const projects = snapshot.projects.some((p) => p.id === event.project.id)        ? Arr.map(snapshot.projects, (p) => (p.id === event.project.id ? event.project : p))        : Arr.append(snapshot.projects, event.project);      return { ...snapshot, projects, snapshotSequence: event.sequence };    }    case "project-removed":      return {        ...snapshot,        projects: Arr.filter(snapshot.projects, (p) => p.id !== event.projectId),        snapshotSequence: event.sequence,      };    case "thread-upserted": {      const threads = snapshot.threads.some((t) => t.id === event.thread.id)        ? Arr.map(snapshot.threads, (t) => (t.id === event.thread.id ? event.thread : t))        : Arr.append(snapshot.threads, event.thread);      return { ...snapshot, threads, snapshotSequence: event.sequence };    }    case "thread-removed":      return {        ...snapshot,        threads: Arr.filter(snapshot.threads, (t) => t.id !== event.threadId),        snapshotSequence: event.sequence,      };    default:      return snapshot;  }}