import { describe, it, expect } from "vitest";
import {
  formatZAR,
  formatDateLong,
  addDays,
  quoteSubtotal,
  vatAmount,
  poSubtotal,
  QUOTE_VALID_DAYS,
  effectiveQuoteDate,
  effectiveValidityDays,
} from "./format";

describe("formatZAR", () => {
  it("formats whole numbers with 2 decimals", () => {
    expect(formatZAR(1234)).toBe("R 1 234.00");
  });
  it("groups thousands with spaces (en-ZA style)", () => {
    expect(formatZAR(1234567.89)).toBe("R 1 234 567.89");
  });
  it("handles zero", () => {
    expect(formatZAR(0)).toBe("R 0.00");
  });
  it("handles small decimals", () => {
    expect(formatZAR(99.5)).toBe("R 99.50");
  });
  it("returns R 0.00 for non-finite numbers", () => {
    expect(formatZAR(NaN)).toBe("R 0.00");
    expect(formatZAR(Infinity)).toBe("R 0.00");
  });
  it("matches the existing sample PDF format", () => {
    // From Quote-CNL-Q009638: Subtotal R 737.06, VAT R 110.56, Total R 847.62
    expect(formatZAR(737.06)).toBe("R 737.06");
    expect(formatZAR(110.56)).toBe("R 110.56");
    expect(formatZAR(847.62)).toBe("R 847.62");
  });
});

describe("formatDateLong", () => {
  it("formats ISO date to '22 June 2026' style", () => {
    expect(formatDateLong("2026-06-22T00:00:00Z")).toBe("22 June 2026");
  });
  it("returns empty string for empty input", () => {
    expect(formatDateLong("")).toBe("");
  });
  it("returns the original string for unparseable input", () => {
    expect(formatDateLong("not-a-date")).toBe("not-a-date");
  });
});

describe("addDays", () => {
  it("adds exactly N days, preserving the calendar date", () => {
    expect(addDays("2026-06-22T00:00:00Z", 30)).toBe(
      "2026-07-22T00:00:00.000Z"
    );
  });
  it("handles month rollover", () => {
    expect(addDays("2026-01-31T00:00:00Z", 1)).toBe(
      "2026-02-01T00:00:00.000Z"
    );
  });
  it("QUOTE_VALID_DAYS is 30 (matches sample PDF)", () => {
    expect(QUOTE_VALID_DAYS).toBe(30);
  });
});

describe("quoteSubtotal", () => {
  it("sums qty * selling_price", () => {
    expect(quoteSubtotal([{ quantity: 1, selling_price: 648.7 }])).toBeCloseTo(648.7);
    expect(
      quoteSubtotal([
        { quantity: 1, selling_price: 648.7 },
        { quantity: 1, selling_price: 88.36 },
      ])
    ).toBeCloseTo(737.06);
  });
  it("returns 0 for empty array", () => {
    expect(quoteSubtotal([])).toBe(0);
  });
});

describe("vatAmount", () => {
  it("computes 15% VAT, rounded to 2dp", () => {
    expect(vatAmount(737.06)).toBe(110.56);
  });
  it("returns 0 for 0 subtotal", () => {
    expect(vatAmount(0)).toBe(0);
  });
});

describe("effectiveQuoteDate", () => {
  it("prefers quote_date when set", () => {
    expect(
      effectiveQuoteDate({
        quote_date: "2026-06-01T00:00:00.000Z",
        created: "2026-06-22T13:40:00.000Z",
      })
    ).toBe("2026-06-01T00:00:00.000Z");
  });
  it("falls back to created when quote_date is empty", () => {
    expect(
      effectiveQuoteDate({
        quote_date: "",
        created: "2026-06-22T13:40:00.000Z",
      })
    ).toBe("2026-06-22T13:40:00.000Z");
  });
  it("returns empty string when both are empty", () => {
    expect(effectiveQuoteDate({ quote_date: "", created: "" })).toBe("");
  });
});

describe("effectiveValidityDays", () => {
  it("uses quote.validity_days when set to a number", () => {
    expect(effectiveValidityDays({ validity_days: 60 })).toBe(60);
  });
  it("falls back to QUOTE_VALID_DAYS (30) when null", () => {
    expect(effectiveValidityDays({ validity_days: null })).toBe(QUOTE_VALID_DAYS);
  });
  it("falls back to QUOTE_VALID_DAYS (30) when undefined", () => {
    expect(effectiveValidityDays({})).toBe(QUOTE_VALID_DAYS);
  });
  // PB defaults an unset number field to 0 (not null). Pre-fix every
  // quote shipped with validity_days=0, which the original `??`
  // passed through and produced a "Valid until: today" PDF.
  it("falls back to QUOTE_VALID_DAYS (30) when 0 (PocketBase default)", () => {
    expect(effectiveValidityDays({ validity_days: 0 })).toBe(QUOTE_VALID_DAYS);
  });
  it("falls back to QUOTE_VALID_DAYS (30) when negative", () => {
    // Defensive — no real path writes this, but a misconfigured
    // input shouldn't ever produce a pre-date expiry.
    expect(effectiveValidityDays({ validity_days: -7 })).toBe(QUOTE_VALID_DAYS);
  });
});

describe("poSubtotal", () => {
  it("sums order_qty × cost_price when order_qty is set", () => {
    expect(poSubtotal([{ order_qty: 3, quantity: 1, cost_price: 100 }])).toBe(300);
  });
  it("falls back to quantity when order_qty is missing", () => {
    expect(poSubtotal([{ quantity: 4, cost_price: 50 }])).toBe(200);
  });
  it("falls back to quantity when order_qty is 0 (blank treated as missing)", () => {
    expect(poSubtotal([{ order_qty: 0, quantity: 2, cost_price: 75 }])).toBe(150);
  });
  it("sums across multiple items", () => {
    expect(poSubtotal([
      { order_qty: 3, quantity: 1, cost_price: 100 },
      { order_qty: 5, quantity: 1, cost_price: 40 },
    ])).toBe(500);
  });
  it("rounds to 2 decimal places (avoids floating-point dust)", () => {
    expect(poSubtotal([
      { quantity: 3, cost_price: 33.33 },
      { quantity: 3, cost_price: 33.33 },
      { quantity: 3, cost_price: 33.34 },
    ])).toBe(300);
  });
  it("returns 0 for an empty array", () => {
    expect(poSubtotal([])).toBe(0);
  });
  it("treats non-numeric cost_price as 0", () => {
    expect(poSubtotal([{ quantity: 5, cost_price: NaN }])).toBe(0);
  });
});