import {
  IPC_CHANNELS,
  addThreadEventSchema,
  addParticipantSchema,
  createThreadSchema,
  listParticipantsSchema,
  listSubscriptionsSchema,
  listSubscribedThreadsSchema,
  listThreadEventsSchema,
  listThreadWaitStatesSchema,
  listThreadsSchema,
  removeParticipantSchema,
  resolveThreadWaitStateSchema,
  setThreadWaitStateSchema,
  subscribeThreadSchema,
  threadGetterSchema,
  unsubscribeThreadSchema,
} from "@shared/contracts";
import type { RegisterCoreHandlersDependencies } from "./ipc-core-common";
import { fail, ok } from "./ipc-core-common";

export function registerThreadHandlers({ registerHandle, db, ensureCompanyExists, publishDomainChanged, emitEvent }: RegisterCoreHandlersDependencies) {
  registerHandle(IPC_CHANNELS.createThread, async (_event, payload) => {
    const input = createThreadSchema.parse(payload);
    const companyError = ensureCompanyExists(input.companyId);
    if (companyError) return companyError;
    const thread = db.createThread({
      companyId: input.companyId,
      title: input.title,
      type: input.type,
      relatedEntityType: input.relatedEntityType ?? null,
      relatedEntityId: input.relatedEntityId ?? null,
    });
    publishDomainChanged();
    return ok(thread);
  });

  registerHandle(IPC_CHANNELS.listThreads, async (_event, payload) => {
    const input = listThreadsSchema.parse(payload);
    const companyError = ensureCompanyExists(input.companyId);
    if (companyError) return companyError;
    const threads = db.listThreads({
      companyId: input.companyId,
      type: input.type,
      relatedEntityType: input.relatedEntityType,
      relatedEntityId: input.relatedEntityId,
      limit: input.limit,
      offset: input.offset,
    });
    return ok(threads);
  });

  registerHandle(IPC_CHANNELS.getThread, async (_event, payload) => {
    const input = threadGetterSchema.parse(payload);
    const companyError = ensureCompanyExists(input.companyId);
    if (companyError) return companyError;
    const thread = db.getThread(input.threadId, input.companyId);
    if (!thread) return fail("THREAD_NOT_FOUND", "Thread not found");
    return ok(thread);
  });

  registerHandle(IPC_CHANNELS.addThreadEvent, async (_event, payload) => {
    const input = addThreadEventSchema.parse(payload);
    const companyError = ensureCompanyExists(input.companyId);
    if (companyError) return companyError;
    const event = db.addThreadEvent({
      threadId: input.threadId,
      actorId: input.actorId,
      actorType: input.actorType,
      eventType: input.eventType,
      body: input.body,
      metadataJson: input.metadataJson,
    });
    publishDomainChanged();
    return ok(event);
  });

  registerHandle(IPC_CHANNELS.listThreadEvents, async (_event, payload) => {
    const input = listThreadEventsSchema.parse(payload);
    const companyError = ensureCompanyExists(input.companyId);
    if (companyError) return companyError;
    const events = db.listThreadEvents(input.threadId, input.companyId, {
      limit: input.limit,
      offset: input.offset,
    });
    return ok(events);
  });

  registerHandle(IPC_CHANNELS.setThreadWaitState, async (_event, payload) => {
    const input = setThreadWaitStateSchema.parse(payload);
    const companyError = ensureCompanyExists(input.companyId);
    if (companyError) return companyError;
    const waitState = db.setThreadWaitState({
      threadId: input.threadId,
      companyId: input.companyId,
      waitingFor: input.waitingFor,
      relatedApprovalId: input.relatedApprovalId ?? null,
      reason: input.reason,
    });
    publishDomainChanged();
    emitEvent({
      type: "thread-wait-state-updated",
      threadId: input.threadId,
      companyId: input.companyId,
      waitStateId: waitState.id,
      action: "created",
    });
    return ok(waitState);
  });

  registerHandle(IPC_CHANNELS.resolveThreadWaitState, async (_event, payload) => {
    const input = resolveThreadWaitStateSchema.parse(payload);
    const companyError = ensureCompanyExists(input.companyId);
    if (companyError) return companyError;

    // Query the wait state before resolving to capture its threadId for the event
    const waitStates = db.listThreadWaitStates(input.companyId);
    const target = waitStates.find((ws) => ws.id === input.waitStateId);
    if (!target) return fail("THREAD_WAIT_STATE_NOT_FOUND", "Wait state not found");

    db.resolveThreadWaitState(input.waitStateId, input.companyId);
    publishDomainChanged();
    emitEvent({
      type: "thread-wait-state-updated",
      threadId: target.threadId,
      companyId: input.companyId,
      waitStateId: input.waitStateId,
      action: "resolved",
    });
    return ok(true);
  });

  registerHandle(IPC_CHANNELS.listThreadWaitStates, async (_event, payload) => {
    const input = listThreadWaitStatesSchema.parse(payload);
    const companyError = ensureCompanyExists(input.companyId);
    if (companyError) return companyError;
    const waitStates = db.listThreadWaitStates(input.companyId, { resolvedOnly: input.resolvedOnly });
    return ok(waitStates);
  });

  registerHandle(IPC_CHANNELS.listParticipants, async (_event, payload) => {
    const input = listParticipantsSchema.parse(payload);
    const thread = db.getThread(input.threadId, input.companyId);
    if (!thread) return fail("THREAD_NOT_FOUND", "Thread not found in this company");
    const participants = db.listParticipants(input.threadId);
    return ok(participants);
  });

  registerHandle(IPC_CHANNELS.addParticipant, async (_event, payload) => {
    const input = addParticipantSchema.parse(payload);
    const thread = db.getThread(input.threadId, input.companyId);
    if (!thread) return fail("THREAD_NOT_FOUND", "Thread not found in this company");
    const participant = db.addParticipant({
      threadId: input.threadId,
      participantId: input.participantId,
      participantType: input.participantType,
      role: input.role,
    });
    publishDomainChanged();
    return ok(participant);
  });

  registerHandle(IPC_CHANNELS.removeParticipant, async (_event, payload) => {
    const input = removeParticipantSchema.parse(payload);
    const thread = db.getThread(input.threadId, input.companyId);
    if (!thread) return fail("THREAD_NOT_FOUND", "Thread not found in this company");
    db.removeParticipant(input.threadId, input.participantId);
    publishDomainChanged();
    return ok(true);
  });

  registerHandle(IPC_CHANNELS.subscribeThread, async (_event, payload) => {
    const input = subscribeThreadSchema.parse(payload);
    const thread = db.getThread(input.threadId, input.companyId);
    if (!thread) return fail("THREAD_NOT_FOUND", "Thread not found in this company");
    const subscription = db.subscribe({
      threadId: input.threadId,
      subscriberId: input.subscriberId,
      subscriberType: input.subscriberType,
      notifyOn: input.notifyOn,
    });
    publishDomainChanged();
    return ok(subscription);
  });

  registerHandle(IPC_CHANNELS.unsubscribeThread, async (_event, payload) => {
    const input = unsubscribeThreadSchema.parse(payload);
    const thread = db.getThread(input.threadId, input.companyId);
    if (!thread) return fail("THREAD_NOT_FOUND", "Thread not found in this company");
    db.unsubscribe(input.threadId, input.subscriberId);
    publishDomainChanged();
    return ok(true);
  });

  registerHandle(IPC_CHANNELS.listSubscriptions, async (_event, payload) => {
    const input = listSubscriptionsSchema.parse(payload);
    const thread = db.getThread(input.threadId, input.companyId);
    if (!thread) return fail("THREAD_NOT_FOUND", "Thread not found in this company");
    const subscriptions = db.listSubscriptions(input.threadId);
    return ok(subscriptions);
  });

  registerHandle(IPC_CHANNELS.listSubscribedThreads, async (_event, payload) => {
    const input = listSubscribedThreadsSchema.parse(payload);
    const threads = db.listSubscribedThreads(input.subscriberId, input.companyId);
    return ok(threads);
  });
}