import { describe, it, expect } from "vitest";
import { lineNet } from "../utils/money";

describe("lineNet (per-item discounted net)", () => {
  it("returns qty × unit_price when there is no discount", () => {
    expect(lineNet(2, 1000, 0)).toBe(2000);
  });

  it("applies a percentage discount to the line net", () => {
    expect(lineNet(2, 1000, 10)).toBe(1800);
  });

  it("treats a 100% discount as zero", () => {
    expect(lineNet(3, 500, 100)).toBe(0);
  });

  it("treats null/undefined/NaN discount as no discount", () => {
    expect(lineNet(2, 1000, null)).toBe(2000);
    expect(lineNet(2, 1000, undefined)).toBe(2000);
    expect(lineNet(2, 1000, NaN)).toBe(2000);
  });
});