import { describe, it, expect } from "vitest";
import { buildDuplicatePrefill, toDateInputValue } from "@/lib/duplicate-po";
import type { DuplicateSourcePo } from "@/lib/duplicate-po";

// A Prisma Decimal stand-in: just needs a toNumber().
const dec = (n: number) => ({ toNumber: () => n });

function makeSource(overrides: Partial<DuplicateSourcePo> = {}): DuplicateSourcePo {
  return {
    title: "Spare parts for HNR1",
    vesselId: "vsl_1",
    accountId: "acc_1",
    companyId: "co_1",
    vendorId: "ven_1",
    projectCode: "Haldia Reach",
    placeOfDelivery: "Pelagia — Cochin yard",
    dateRequired: new Date("2026-07-15T00:00:00.000Z"),
    piQuotationNo: "INV-001",
    piQuotationDate: new Date("2026-06-01T00:00:00.000Z"),
    requisitionNo: "REQ-42",
    requisitionDate: new Date("2026-05-20T00:00:00.000Z"),
    terms: [{ category: "Delivery", text: "Within 4 to 5 days" }],
    lineItems: [
      {
        name: "Gasket",
        description: "Rubber gasket",
        quantity: dec(3),
        unit: "pc",
        size: "M",
        unitPrice: dec(120.5),
        gstRate: dec(0.18),
        productId: "prod_1",
        accountId: null,
      },
    ],
    ...overrides,
  };
}

describe("buildDuplicatePrefill", () => {
  it("copies the editable order fields onto the new draft", () => {
    const r = buildDuplicatePrefill(makeSource());
    expect(r.initialTitle).toBe("Spare parts for HNR1");
    expect(r.initialVesselId).toBe("vsl_1");
    expect(r.initialAccountId).toBe("acc_1");
    expect(r.initialCompanyId).toBe("co_1");
    expect(r.initialVendorId).toBe("ven_1");
    expect(r.initialProjectCode).toBe("Haldia Reach");
    expect(r.initialPlaceOfDelivery).toBe("Pelagia — Cochin yard");
    expect(r.initialPiQuotationNo).toBe("INV-001");
    expect(r.initialRequisitionNo).toBe("REQ-42");
  });

  it("formats dates as yyyy-MM-dd for native date inputs", () => {
    const r = buildDuplicatePrefill(makeSource());
    expect(r.initialDateRequired).toBe("2026-07-15");
    expect(r.initialPiQuotationDate).toBe("2026-06-01");
    expect(r.initialRequisitionDate).toBe("2026-05-20");
  });

  it("maps line items to the editor shape, converting Decimals to numbers", () => {
    const r = buildDuplicatePrefill(makeSource());
    expect(r.initialLineItems).toEqual([
      {
        name: "Gasket",
        description: "Rubber gasket",
        quantity: 3,
        unit: "pc",
        size: "M",
        unitPrice: 120.5,
        gstRate: 0.18,
        productId: "prod_1",
        accountId: undefined,
      },
    ]);
  });

  it("enables per-item accounting codes only when a line item carries one", () => {
    expect(buildDuplicatePrefill(makeSource()).initialMultiAccount).toBe(false);
    const multi = makeSource({
      lineItems: [
        { name: "A", quantity: dec(1), unit: "pc", unitPrice: dec(10), accountId: "acc_2" },
      ],
    });
    const r = buildDuplicatePrefill(multi);
    expect(r.initialMultiAccount).toBe(true);
    expect(r.initialLineItems[0].accountId).toBe("acc_2");
  });

  it("defaults a missing gstRate to 0.18", () => {
    const src = makeSource({
      lineItems: [{ name: "A", quantity: dec(2), unit: "pc", unitPrice: dec(5) }],
    });
    expect(buildDuplicatePrefill(src).initialLineItems[0].gstRate).toBe(0.18);
  });

  it("uses the saved terms snapshot when present", () => {
    const r = buildDuplicatePrefill(makeSource());
    expect(r.initialTerms).toEqual([{ category: "Delivery", text: "Within 4 to 5 days" }]);
  });

  it("falls back to legacy tc* terms when no JSON snapshot exists", () => {
    const src = makeSource({
      terms: null,
      tcDelivery: "Next day",
      tcPaymentTerms: "Net 15",
    });
    const r = buildDuplicatePrefill(src);
    expect(r.initialTerms).toEqual(
      expect.arrayContaining([
        { category: "Delivery", text: "Next day" },
        { category: "Payment Terms", text: "Net 15" },
      ])
    );
  });

  it("normalises absent optional fields to undefined/null", () => {
    const src = makeSource({
      companyId: null,
      vendorId: null,
      projectCode: null,
      placeOfDelivery: null,
      dateRequired: null,
      piQuotationNo: null,
      piQuotationDate: null,
      requisitionNo: null,
      requisitionDate: null,
    });
    const r = buildDuplicatePrefill(src);
    expect(r.initialCompanyId).toBeUndefined();
    expect(r.initialVendorId).toBeUndefined();
    expect(r.initialDateRequired).toBeUndefined();
    expect(r.initialPiQuotationNo).toBeUndefined();
    expect(r.initialProjectCode).toBeNull();
    expect(r.initialPlaceOfDelivery).toBeNull();
  });
});

describe("toDateInputValue", () => {
  it("returns yyyy-MM-dd for a date and undefined for null", () => {
    expect(toDateInputValue(new Date("2026-01-09T12:00:00.000Z"))).toBe("2026-01-09");
    expect(toDateInputValue(null)).toBeUndefined();
    expect(toDateInputValue(undefined)).toBeUndefined();
  });
});