const { suggestInvoiceExpenseType } = require("../../../src/services/invoiceExpenseClassification");

const enabledTypes = [
  { id: "train-type", code: "travel_train", enabled: true },
  { id: "hotel-type", code: "travel_hotel", enabled: true },
  { id: "meal-type", code: "business_client_meal", enabled: true },
];

function invoiceWithCategory(documentCategory, extra = {}) {
  return { ocr_result: { result_json: { documentCategory } }, ...extra };
}

describe("invoice expense classification", () => {
  it("suggests the enabled train type from a recognized electronic train ticket", () => {
    expect(suggestInvoiceExpenseType(invoiceWithCategory("electronic_train_ticket"), enabledTypes))
      .toEqual({ expenseTypeId: "train-type", source: "document_category" });
  });

  it.each(["vat_invoice", "full_vat_invoice", "unknown", null])(
    "does not guess an expense type from category %s, seller, filename or amount",
    (category) => {
      expect(suggestInvoiceExpenseType(invoiceWithCategory(category, {
        seller_name: "合成酒店餐饮公司",
        original_name: "办公用品.pdf",
        total_amount: "100.00",
      }), enabledTypes)).toBeNull();
    },
  );

  it("does not substitute another enabled type when the matching type is disabled", () => {
    const expenseTypes = enabledTypes.map((type) => ({ ...type, enabled: type.code !== "travel_train" }));
    expect(suggestInvoiceExpenseType(invoiceWithCategory("electronic_train_ticket"), expenseTypes)).toBeNull();
  });

  it("does not substitute the first enabled type when the matching type is absent", () => {
    expect(suggestInvoiceExpenseType(invoiceWithCategory("electronic_train_ticket"), enabledTypes.slice(1)))
      .toBeNull();
  });

  it("does not infer from the historical provider or generic upload type", () => {
    expect(suggestInvoiceExpenseType({ ocr_provider: "tencent", ocr_type: "vat" }, enabledTypes)).toBeNull();
  });

  it("does not infer from client-facing category fields instead of persisted OCR metadata", () => {
    expect(suggestInvoiceExpenseType({ documentCategory: "electronic_train_ticket" }, enabledTypes)).toBeNull();
  });

  it("does not mutate invoice data or expense types", () => {
    const invoice = invoiceWithCategory("electronic_train_ticket");
    const before = JSON.stringify({ invoice, enabledTypes });
    suggestInvoiceExpenseType(invoice, enabledTypes);
    expect(JSON.stringify({ invoice, enabledTypes })).toBe(before);
  });
});