import {  PreviewAutomationClientDisconnectedError,  PreviewAutomationControlInterruptedError,  PreviewAutomationExecutionError,  PreviewAutomationHostNotConnectedError,  PreviewAutomationInvalidSelectorError,  PreviewAutomationMalformedResponseError,  PreviewAutomationNoFocusedOwnerError,  PreviewAutomationRemoteUnavailableError,  PreviewAutomationRequestQueueClosedError,  PreviewAutomationResultTooLargeError,  PreviewAutomationTabNotFoundError,  PreviewAutomationTimeoutError,  PreviewAutomationUnsupportedClientError,  type PreviewAutomationError,  type PreviewAutomationOperation,  type PreviewAutomationOwner,  type PreviewAutomationOwnerIdentity,  type PreviewAutomationRequest,  type PreviewAutomationResponse,  type PreviewTabId,} from "@t3tools/contracts";import * as Context from "effect/Context";import * as Deferred from "effect/Deferred";import * as Effect from "effect/Effect";import * as Layer from "effect/Layer";import * as Option from "effect/Option";import * as Queue from "effect/Queue";import * as Stream from "effect/Stream";import * as SynchronizedRef from "effect/SynchronizedRef"; import * as McpInvocationContext from "./McpInvocationContext.ts"; export interface PreviewAutomationInvokeInput {  readonly scope: McpInvocationContext.McpInvocationScope;  readonly operation: PreviewAutomationOperation;  readonly input: unknown;  readonly tabId?: PreviewTabId;  readonly timeoutMs?: number;} export class PreviewAutomationBroker extends Context.Service<  PreviewAutomationBroker,  {    readonly connect: (      owner: PreviewAutomationOwner,    ) => Effect.Effect<Stream.Stream<PreviewAutomationRequest>>;    readonly reportOwner: (      owner: PreviewAutomationOwner,    ) => Effect.Effect<void, PreviewAutomationError>;    readonly clearOwner: (owner: PreviewAutomationOwnerIdentity) => Effect.Effect<void>;    readonly respond: (      response: PreviewAutomationResponse,    ) => Effect.Effect<void, PreviewAutomationError>;    readonly invoke: <A = unknown>(      request: PreviewAutomationInvokeInput,    ) => Effect.Effect<A, PreviewAutomationError>;  }>()("t3/mcp/PreviewAutomationBroker") {} interface ClientConnection {  readonly clientId: string;  readonly queue: Queue.Queue<PreviewAutomationRequest>;} interface PendingRequest {  readonly queue: ClientConnection["queue"];  readonly deferred: Deferred.Deferred<unknown, PreviewAutomationError>;  readonly context: PreviewAutomationRequestErrorContext;} interface PreviewAutomationRequestErrorContext {  readonly operation: PreviewAutomationOperation;  readonly environmentId: McpInvocationContext.McpInvocationScope["environmentId"];  readonly threadId: McpInvocationContext.McpInvocationScope["threadId"];  readonly providerSessionId: string;  readonly providerInstanceId: McpInvocationContext.McpInvocationScope["providerInstanceId"];  readonly clientId: string;  readonly requestId: string;  readonly tabId?: PreviewTabId;  readonly timeoutMs: number;  readonly selectorKind?: "locator" | "selector";  readonly selectorLength?: number;} interface BrokerState {  readonly clients: ReadonlyMap<string, ClientConnection>;  readonly owners: ReadonlyMap<string, PreviewAutomationOwner>;  readonly pending: ReadonlyMap<string, PendingRequest>;  readonly requestSequence: number;} const selectorDiagnosticsFromInput = (  input: unknown,): Pick<PreviewAutomationRequestErrorContext, "selectorKind" | "selectorLength"> => {  if (typeof input !== "object" || input === null) return {};  if ("locator" in input && typeof input.locator === "string") {    return { selectorKind: "locator", selectorLength: input.locator.length };  }  if ("selector" in input && typeof input.selector === "string") {    return { selectorKind: "selector", selectorLength: input.selector.length };  }  return {};}; type RemoteDetailKind = "null" | "array" | "object" | "string" | "number" | "boolean"; function remoteDetailKind(detail: unknown): RemoteDetailKind {  if (detail === null) return "null";  if (Array.isArray(detail)) return "array";  switch (typeof detail) {    case "string":      return "string";    case "number":      return "number";    case "boolean":      return "boolean";    default:      return "object";  }} const classifyResponseError = (  context: PreviewAutomationRequestErrorContext,  error: NonNullable<PreviewAutomationResponse["error"]>,): PreviewAutomationError => {  const remoteDiagnostics = {    remoteTag: error._tag,    remoteMessageLength: error.message.length,    ...(error.detail === undefined ? {} : { remoteDetailKind: remoteDetailKind(error.detail) }),    cause: error,  };  switch (error._tag) {    case "PreviewAutomationNoFocusedOwnerError":      return new PreviewAutomationNoFocusedOwnerError({        ...context,        ...remoteDiagnostics,      });    case "PreviewAutomationUnsupportedClientError":      return new PreviewAutomationUnsupportedClientError({        ...context,        ...remoteDiagnostics,      });    case "PreviewAutomationTabNotFoundError":      return new PreviewAutomationTabNotFoundError({        ...context,        ...remoteDiagnostics,      });    case "PreviewAutomationTimeoutError":      return new PreviewAutomationTimeoutError({        ...context,        ...remoteDiagnostics,      });    case "PreviewAutomationControlInterruptedError":      return new PreviewAutomationControlInterruptedError({        ...context,        ...remoteDiagnostics,      });    case "PreviewAutomationInvalidSelectorError": {      return new PreviewAutomationInvalidSelectorError({        ...context,        ...remoteDiagnostics,      });    }    case "PreviewAutomationResultTooLargeError": {      const detail =        typeof error.detail === "object" && error.detail !== null ? error.detail : undefined;      const maximumBytes =        detail &&        "maximumBytes" in detail &&        typeof detail.maximumBytes === "number" &&        Number.isInteger(detail.maximumBytes) &&        detail.maximumBytes > 0          ? detail.maximumBytes          : undefined;      return new PreviewAutomationResultTooLargeError({        ...context,        ...remoteDiagnostics,        ...(maximumBytes === undefined ? {} : { maximumBytes }),      });    }    case "PreviewAutomationUnavailableError":      return new PreviewAutomationRemoteUnavailableError({        ...context,        ...remoteDiagnostics,      });    default:      return new PreviewAutomationExecutionError({        ...context,        ...remoteDiagnostics,      });  }}; export const make = Effect.gen(function* PreviewAutomationBrokerMake() {  const state = yield* SynchronizedRef.make<BrokerState>({    clients: new Map(),    owners: new Map(),    pending: new Map(),    requestSequence: 0,  });   const disconnect = Effect.fn("PreviewAutomationBroker.disconnect")(function* (    clientId: string,    queue: ClientConnection["queue"],  ) {    const toFail = yield* SynchronizedRef.modify(state, (current) => {      const clients = new Map(current.clients);      const owners = new Map(current.owners);      const pending = new Map(current.pending);      const disconnected: PendingRequest[] = [];      if (current.clients.get(clientId)?.queue === queue) {        clients.delete(clientId);        owners.delete(clientId);      }      for (const [requestId, entry] of pending) {        if (entry.queue === queue) {          pending.delete(requestId);          disconnected.push(entry);        }      }      return [disconnected, { ...current, clients, owners, pending }] as const;    });    yield* Effect.forEach(      toFail,      ({ deferred, context }) =>        Deferred.fail(deferred, new PreviewAutomationClientDisconnectedError(context)),      { discard: true },    );    yield* Queue.shutdown(queue);  });   const connect: PreviewAutomationBroker["Service"]["connect"] = Effect.fn(    "PreviewAutomationBroker.connect",  )(function* (owner) {    const clientId = owner.clientId;    const queue = yield* Queue.unbounded<import("@t3tools/contracts").PreviewAutomationRequest>();    const previous = yield* SynchronizedRef.modify(state, (current) => {      const clients = new Map(current.clients);      const owners = new Map(current.owners);      const existingOwner = current.owners.get(clientId);      clients.set(clientId, { clientId, queue });      owners.set(        clientId,        existingOwner?.environmentId === owner.environmentId &&          existingOwner.threadId === owner.threadId          ? { ...existingOwner, supportsAutomation: owner.supportsAutomation }          : owner,      );      return [current.clients.get(clientId), { ...current, clients, owners }] as const;    });    if (previous) yield* disconnect(clientId, previous.queue);    return Stream.fromQueue(queue).pipe(Stream.ensuring(disconnect(clientId, queue)));  });   const reportOwner: PreviewAutomationBroker["Service"]["reportOwner"] = Effect.fn(    "PreviewAutomationBroker.reportOwner",  )(function* (owner) {    yield* SynchronizedRef.update(state, (current) => {      const owners = new Map(current.owners);      owners.set(owner.clientId, owner);      return { ...current, owners };    });  });   const clearOwner: PreviewAutomationBroker["Service"]["clearOwner"] = Effect.fn(    "PreviewAutomationBroker.clearOwner",  )(function* (owner) {    yield* SynchronizedRef.update(state, (current) => {      const currentOwner = current.owners.get(owner.clientId);      if (        !currentOwner ||        currentOwner.environmentId !== owner.environmentId ||        currentOwner.threadId !== owner.threadId      ) {        return current;      }      const owners = new Map(current.owners);      owners.delete(owner.clientId);      return { ...current, owners };    });  });   const respond: PreviewAutomationBroker["Service"]["respond"] = Effect.fn(    "PreviewAutomationBroker.respond",  )(function* (response) {    const pending = yield* SynchronizedRef.modify(state, (current) => {      const entry = current.pending.get(response.requestId);      if (!entry) return [undefined, current] as const;      const next = new Map(current.pending);      next.delete(response.requestId);      return [entry, { ...current, pending: next }] as const;    });    if (!pending) return;    if (response.ok) {      yield* Deferred.succeed(pending.deferred, response.result);    } else {      yield* Deferred.fail(        pending.deferred,        response.error          ? classifyResponseError(pending.context, response.error)          : new PreviewAutomationMalformedResponseError(pending.context),      );    }  });   const invoke = Effect.fn("PreviewAutomationBroker.invoke")(function* <A = unknown>(    input: Parameters<PreviewAutomationBroker["Service"]["invoke"]>[0],  ): Effect.fn.Return<A, PreviewAutomationError> {    const current = yield* SynchronizedRef.get(state);    const candidates = Array.from(current.owners.values())      .filter(        (owner) =>          owner.environmentId === input.scope.environmentId &&          owner.threadId === input.scope.threadId &&          owner.supportsAutomation,      )      .sort((left, right) => right.focusedAt.localeCompare(left.focusedAt));    const owner = candidates.find((candidate) => current.clients.has(candidate.clientId));    if (!owner) {      const disconnectedOwner = candidates[0];      if (disconnectedOwner) {        return yield* new PreviewAutomationHostNotConnectedError({          operation: input.operation,          environmentId: input.scope.environmentId,          threadId: input.scope.threadId,          providerSessionId: input.scope.providerSessionId,          providerInstanceId: input.scope.providerInstanceId,          clientId: disconnectedOwner.clientId,        });      }      return yield* new PreviewAutomationNoFocusedOwnerError({        operation: input.operation,        environmentId: input.scope.environmentId,        threadId: input.scope.threadId,        providerSessionId: input.scope.providerSessionId,        providerInstanceId: input.scope.providerInstanceId,      });    }    const connection = current.clients.get(owner.clientId);    if (!connection) {      return yield* new PreviewAutomationHostNotConnectedError({        operation: input.operation,        environmentId: input.scope.environmentId,        threadId: input.scope.threadId,        providerSessionId: input.scope.providerSessionId,        providerInstanceId: input.scope.providerInstanceId,        clientId: owner.clientId,      });    }    const timeoutMs = input.timeoutMs ?? 15_000;    const deferred = yield* Deferred.make<unknown, PreviewAutomationError>();    const [requestId, requestContext] = yield* SynchronizedRef.modify(state, (next) => {      const requestId = `preview-${next.requestSequence}`;      const tabId = input.tabId ?? owner.tabId ?? undefined;      const selectorDiagnostics = selectorDiagnosticsFromInput(input.input);      const context: PreviewAutomationRequestErrorContext = {        operation: input.operation,        environmentId: input.scope.environmentId,        threadId: input.scope.threadId,        providerSessionId: input.scope.providerSessionId,        providerInstanceId: input.scope.providerInstanceId,        clientId: owner.clientId,        requestId,        ...(tabId === undefined ? {} : { tabId }),        timeoutMs,        ...selectorDiagnostics,      };      const pending = new Map(next.pending);      pending.set(requestId, { queue: connection.queue, deferred, context });      return [        [requestId, context] as const,        { ...next, pending, requestSequence: next.requestSequence + 1 },      ] as const;    });    const removePending = SynchronizedRef.update(state, (next) => {      if (!next.pending.has(requestId)) return next;      const pending = new Map(next.pending);      pending.delete(requestId);      return { ...next, pending };    });    const awaitResponse = Effect.fn("PreviewAutomationBroker.awaitResponse")(function* () {      const offered = yield* Queue.offer(connection.queue, {        requestId,        threadId: input.scope.threadId,        tabId: requestContext.tabId,        operation: input.operation,        input: input.input,        timeoutMs,      });      if (!offered) {        const completion = yield* Deferred.poll(deferred);        if (Option.isSome(completion)) {          return (yield* completion.value) as A;        }        return yield* new PreviewAutomationRequestQueueClosedError(requestContext);      }      const result = yield* Deferred.await(deferred).pipe(Effect.timeoutOption(timeoutMs));      return yield* Option.match(result, {        onNone: () => Effect.fail(new PreviewAutomationTimeoutError(requestContext)),        onSome: (value) => Effect.succeed(value as A),      });    });    return yield* awaitResponse().pipe(Effect.ensuring(removePending));  });   return PreviewAutomationBroker.of({ connect, reportOwner, clearOwner, respond, invoke });}).pipe(Effect.withSpan("PreviewAutomationBroker.make")); export const layer = Layer.effect(PreviewAutomationBroker, make);