const { enqueueIntegrationEvent } = require('./outbox');

const ERP_JOURNAL_EVENT_TYPES = Object.freeze(['erp.journal.export', 'erp.reimbursement.paid']);
const REIMBURSEMENT_JOURNAL_DEDUPE_PREFIX = 'reimbursement';
const TRAVEL_ORDER_JOURNAL_DEDUPE_PREFIX = 'travel_order';

function toDateOnly(value) {
  if (!value) {
    return null;
  }
  try {
    return new Date(value).toISOString().slice(0, 10);
  } catch {
    return null;
  }
}

function toIsoString(value) {
  if (!value) {
    return null;
  }
  try {
    return new Date(value).toISOString();
  } catch {
    return null;
  }
}

function resolveReimbursementLegalEntityCode(reimbursement) {
  return reimbursement?.owner?.legal_entity?.code ?? reimbursement?.submitter?.legal_entity?.code ?? null;
}

function resolveTravelRequestLegalEntityCode(travelOrder) {
  return travelOrder?.travel_request?.legal_entity?.code ?? null;
}

function resolveTravelRequestCostCenterCode(travelOrder) {
  return travelOrder?.travel_request?.cost_center?.code ?? null;
}

function resolveTravelRequestBudgetPoolCode(travelOrder) {
  return travelOrder?.travel_request?.budget_pool?.code ?? null;
}

function buildReimbursementJournalPayload(input) {
  const reimbursement = input?.reimbursement ?? {};
  const occurredAt =
    toIsoString(reimbursement.paid_at) ??
    (reimbursement.payment_date ? `${toDateOnly(reimbursement.payment_date)}T00:00:00.000Z` : null);

  return {
    journalType: 'reimbursement_paid',
    sourceEventName: 'reimbursement.paid',
    entityType: 'reimbursement_form',
    entityId: reimbursement.id,
    documentNo: reimbursement.form_number ?? null,
    currencyCode: 'CNY',
    totalAmount: reimbursement.total_amount?.toString?.() ?? null,
    occurredAt,
    paymentVoucherNo: reimbursement.payment_voucher_no ?? null,
    paymentDate: toDateOnly(reimbursement.payment_date),
    dimensions: {
      departmentId: reimbursement.department_id ?? null,
      ownerEmployeeId: reimbursement.owner_id ?? null,
      submitterEmployeeId: reimbursement.submitter_id ?? null,
      legalEntityCode: resolveReimbursementLegalEntityCode(reimbursement),
      costCenterCode: null,
    },
    reimbursementId: reimbursement.id,
    formNumber: reimbursement.form_number ?? null,
  };
}

function buildTravelOrderPaymentJournalPayload(input) {
  const travelOrder = input?.travelOrder ?? {};
  const travelRequest = travelOrder?.travel_request ?? {};
  const occurredAt =
    toIsoString(travelOrder.paid_at) ??
    (travelOrder.payment_date ? `${toDateOnly(travelOrder.payment_date)}T00:00:00.000Z` : null) ??
    toIsoString(travelOrder.updated_at) ??
    toIsoString(travelOrder.created_at);

  return {
    journalType: 'travel_order_payment',
    sourceEventName: 'travel_order.paid',
    entityType: 'travel_order',
    entityId: travelOrder.id ?? null,
    documentNo: travelOrder.external_order_no ?? null,
    currencyCode: travelOrder.currency ?? 'CNY',
    totalAmount: travelOrder.amount?.toString?.() ?? null,
    occurredAt,
    paymentVoucherNo: travelOrder.payment_voucher_no ?? null,
    paymentDate: toDateOnly(travelOrder.payment_date),
    paymentChannel: travelOrder.payment_channel ?? null,
    dimensions: {
      departmentId: travelOrder.department_id ?? travelRequest.department_id ?? null,
      employeeId: travelOrder.employee_id ?? null,
      applicantEmployeeId: travelRequest.applicant_employee_id ?? null,
      submitterEmployeeId: travelRequest.submitter_id ?? null,
      legalEntityCode: resolveTravelRequestLegalEntityCode(travelOrder),
      costCenterCode: resolveTravelRequestCostCenterCode(travelOrder),
      budgetPoolCode: resolveTravelRequestBudgetPoolCode(travelOrder),
    },
    references: {
      travelOrderId: travelOrder.id ?? null,
      travelRequestId: travelOrder.travel_request_id ?? null,
      requestNo: travelRequest.request_no ?? null,
      externalOrderNo: travelOrder.external_order_no ?? null,
      source: travelOrder.source ?? null,
      linkedReimbursementId: travelOrder.linked_reimbursement_id ?? null,
    },
  };
}

function buildReimbursementJournalDedupeKey(reimbursementId) {
  return `${REIMBURSEMENT_JOURNAL_DEDUPE_PREFIX}:${reimbursementId}:paid`;
}

function buildTravelOrderPaymentJournalDedupeKey(travelOrderId) {
  return `${TRAVEL_ORDER_JOURNAL_DEDUPE_PREFIX}:${travelOrderId}:paid`;
}

async function enqueueReimbursementJournalExport(prisma, config, input) {
  const payload = input?.payload ?? buildReimbursementJournalPayload({ reimbursement: input?.reimbursement });

  const enqueued = await enqueueIntegrationEvent(prisma, {
    eventType: 'erp.journal.export',
    payload,
    dedupeKey: buildReimbursementJournalDedupeKey(payload.entityId),
    maxAttempts: config.integrationOutboxMaxAttempts,
    actorId: input?.actorId ?? null,
    requeueOnFailure: true,
  });

  return {
    ...enqueued,
    eventType: 'erp.journal.export',
    payload,
  };
}

async function enqueueTravelOrderPaymentJournalExport(prisma, config, input) {
  const payload = input?.payload ?? buildTravelOrderPaymentJournalPayload({ travelOrder: input?.travelOrder });

  const enqueued = await enqueueIntegrationEvent(prisma, {
    eventType: 'erp.journal.export',
    payload,
    dedupeKey: buildTravelOrderPaymentJournalDedupeKey(payload.entityId),
    maxAttempts: config.integrationOutboxMaxAttempts,
    actorId: input?.actorId ?? null,
    requeueOnFailure: true,
  });

  return {
    ...enqueued,
    eventType: 'erp.journal.export',
    payload,
  };
}

function mapIntegrationBinding(record) {
  if (!record) {
    return null;
  }

  return {
    id: record.id,
    provider: record.provider,
    entityType: record.entity_type,
    localId: record.local_id,
    externalId: record.external_id ?? null,
    externalCode: record.external_code ?? null,
    lastSyncedAt: record.last_synced_at?.toISOString?.() ?? null,
  };
}

function mapIntegrationOutboxState(record) {
  if (!record) {
    return null;
  }

  return {
    id: record.id,
    eventType: record.event_type,
    status: record.status,
    lastError: record.last_error ?? null,
    processedAt: record.processed_at?.toISOString?.() ?? null,
    updatedAt: record.updated_at?.toISOString?.() ?? null,
  };
}

async function findLatestReimbursementJournalOutbox(prisma, reimbursementId) {
  const current = await prisma.integrationOutbox.findFirst({
    where: {
      event_type: 'erp.journal.export',
      dedupe_key: buildReimbursementJournalDedupeKey(reimbursementId),
    },
    orderBy: { updated_at: 'desc' },
  });

  if (current) {
    return current;
  }

  return prisma.integrationOutbox.findFirst({
    where: {
      event_type: 'erp.reimbursement.paid',
      dedupe_key: reimbursementId,
    },
    orderBy: { updated_at: 'desc' },
  });
}

async function findLatestTravelOrderPaymentJournalOutbox(prisma, travelOrderId) {
  return prisma.integrationOutbox.findFirst({
    where: {
      event_type: 'erp.journal.export',
      dedupe_key: buildTravelOrderPaymentJournalDedupeKey(travelOrderId),
    },
    orderBy: { updated_at: 'desc' },
  });
}

async function buildReimbursementJournalPreview(prisma, reimbursement) {
  const [binding, outbox] = await Promise.all([
    prisma.integrationBinding.findUnique({
      where: {
        provider_entity_type_local_id: {
          provider: 'erp',
          entity_type: 'reimbursement_journal',
          local_id: reimbursement.id,
        },
      },
    }),
    findLatestReimbursementJournalOutbox(prisma, reimbursement.id),
  ]);

  const journal = buildReimbursementJournalPayload({ reimbursement });
  const exportState = {
    externalId: binding?.external_id ?? null,
    lastOutboxId: outbox?.id ?? null,
    lastOutboxStatus: outbox?.status ?? null,
    lastError: outbox?.last_error ?? null,
    exportedAt: binding?.last_synced_at?.toISOString?.() ?? outbox?.processed_at?.toISOString?.() ?? null,
  };

  return {
    journal,
    exportState,
    binding: mapIntegrationBinding(binding),
    outbox: mapIntegrationOutboxState(outbox),
  };
}

async function buildTravelOrderPaymentJournalPreview(prisma, travelOrderInput) {
  const travelOrder = travelOrderInput?.travel_request
    ? travelOrderInput
    : await prisma.travelOrder.findUnique({
        where: { id: travelOrderInput.id },
        select: {
          id: true,
          source: true,
          external_order_no: true,
          employee_id: true,
          department_id: true,
          linked_reimbursement_id: true,
          travel_request_id: true,
          amount: true,
          currency: true,
          payment_voucher_no: true,
          payment_date: true,
          payment_channel: true,
          paid_at: true,
          created_at: true,
          updated_at: true,
          travel_request: {
            select: {
              id: true,
              request_no: true,
              department_id: true,
              applicant_employee_id: true,
              submitter_id: true,
              legal_entity: { select: { code: true } },
              cost_center: { select: { code: true } },
              budget_pool: { select: { code: true } },
            },
          },
        },
      });

  if (!travelOrder) {
    return {
      journal: null,
      exportState: {
        externalId: null,
        lastOutboxId: null,
        lastOutboxStatus: null,
        lastError: null,
        exportedAt: null,
      },
      binding: null,
      outbox: null,
    };
  }

  const [binding, outbox] = await Promise.all([
    prisma.integrationBinding.findUnique({
      where: {
        provider_entity_type_local_id: {
          provider: 'erp',
          entity_type: 'travel_order_payment_journal',
          local_id: travelOrder.id,
        },
      },
    }),
    findLatestTravelOrderPaymentJournalOutbox(prisma, travelOrder.id),
  ]);

  const journal = buildTravelOrderPaymentJournalPayload({ travelOrder });
  const exportState = {
    externalId: binding?.external_id ?? null,
    lastOutboxId: outbox?.id ?? null,
    lastOutboxStatus: outbox?.status ?? null,
    lastError: outbox?.last_error ?? null,
    exportedAt: binding?.last_synced_at?.toISOString?.() ?? outbox?.processed_at?.toISOString?.() ?? null,
  };

  return {
    journal,
    exportState,
    binding: mapIntegrationBinding(binding),
    outbox: mapIntegrationOutboxState(outbox),
  };
}

module.exports = {
  ERP_JOURNAL_EVENT_TYPES,
  buildReimbursementJournalDedupeKey,
  buildReimbursementJournalPayload,
  buildReimbursementJournalPreview,
  buildTravelOrderPaymentJournalDedupeKey,
  buildTravelOrderPaymentJournalPayload,
  buildTravelOrderPaymentJournalPreview,
  enqueueReimbursementJournalExport,
  enqueueTravelOrderPaymentJournalExport,
  findLatestReimbursementJournalOutbox,
  findLatestTravelOrderPaymentJournalOutbox,
};