/// <reference types="bun" />

import { describe, expect, test } from "bun:test";
import {
  formatZonedDateTime,
  addZonedCalendarInterval,
  getDefaultScheduledSendAt,
  isValidTimeZone,
  toLocalDateTimeInputValue,
  zonedDateTimeToInstant,
} from "../src/time-zone";
import {
  EXPENSE_CATEGORIES,
  formatElapsedSeconds,
  getEffectiveInvoiceStatus,
  getDaysPastDue,
  parseReceiptText,
} from "../src";

describe("shared domain behavior", () => {
  test("exposes the expense category vocabulary", () => {
    expect(EXPENSE_CATEGORIES).toContain("Professional Services");
  });

  test("calculates overdue status at day precision", () => {
    const yesterday = new Date();
    yesterday.setDate(yesterday.getDate() - 1);
    expect(getEffectiveInvoiceStatus("sent", yesterday)).toBe("overdue");
    expect(getEffectiveInvoiceStatus("paid", yesterday)).toBe("paid");
  });

  test("counts calendar days rather than 24-hour blocks across fall DST", () => {
    expect(
      getDaysPastDue(
        "sent",
        "2026-11-01",
        "America/New_York",
        new Date("2026-11-02T17:00:00.000Z"),
      ),
    ).toBe(1);
  });

  test("formats elapsed time", () => {
    expect(formatElapsedSeconds(3_661)).toBe("01:01:01");
  });

  test("extracts receipt totals and line items", () => {
    const receipt = parseReceiptText(
      "Corner Store\nCoffee 3.50\nSubtotal 3.50\nTax 0.31\nTotal 3.81",
    );
    expect(receipt.amount).toBe(3.81);
    expect(receipt.tax).toBe(0.31);
    expect(receipt.items[0]?.name).toBe("Coffee");
  });
});

describe("time-zone helpers", () => {
  test("formats the same instant in the selected IANA time zone", () => {
    const instant = new Date("2026-08-17T16:30:00.000Z");
    expect(formatZonedDateTime(instant, "America/New_York")).toContain(
      "12:30 PM",
    );
    expect(formatZonedDateTime(instant, "America/Los_Angeles")).toContain(
      "9:30 AM",
    );
  });

  test("validates IANA time zones", () => {
    expect(isValidTimeZone("America/New_York")).toBe(true);
    expect(isValidTimeZone("not/a-zone")).toBe(false);
  });

  test("converts Eastern wall time to the correct absolute instant", () => {
    expect(
      zonedDateTimeToInstant(
        "2026-08-17T09:00",
        "America/New_York",
      ).toISOString(),
    ).toBe("2026-08-17T13:00:00.000Z");
  });

  test("rejects nonexistent spring-forward wall times", () => {
    expect(() =>
      zonedDateTimeToInstant("2026-03-08T02:30", "America/New_York"),
    ).toThrow("does not exist");
  });

  test("disambiguates both occurrences of a fall-back wall time", () => {
    expect(
      zonedDateTimeToInstant(
        "2026-11-01T01:30",
        "America/New_York",
        "earlier",
      ).toISOString(),
    ).toBe("2026-11-01T05:30:00.000Z");
    expect(
      zonedDateTimeToInstant(
        "2026-11-01T01:30",
        "America/New_York",
        "later",
      ).toISOString(),
    ).toBe("2026-11-01T06:30:00.000Z");
  });

  test("supports half-hour DST transitions", () => {
    const earlier = zonedDateTimeToInstant(
      "2026-04-05T01:45",
      "Australia/Lord_Howe",
      "earlier",
    );
    const later = zonedDateTimeToInstant(
      "2026-04-05T01:45",
      "Australia/Lord_Howe",
      "later",
    );
    expect(later.getTime() - earlier.getTime()).toBe(30 * 60_000);
  });

  test("preserves Eastern wall time across DST and clamps month end", () => {
    expect(
      addZonedCalendarInterval(
        new Date("2026-03-01T14:00:00.000Z"),
        "weekly",
        "America/New_York",
      ).toISOString(),
    ).toBe("2026-03-08T13:00:00.000Z");
    expect(
      addZonedCalendarInterval(
        new Date("2026-01-31T14:00:00.000Z"),
        "monthly",
        "America/New_York",
      ).toISOString(),
    ).toBe("2026-02-28T14:00:00.000Z");
  });

  test("rounds the default schedule to the next local hour", () => {
    const result = getDefaultScheduledSendAt(new Date(2026, 7, 17, 10, 42, 19));
    expect(toLocalDateTimeInputValue(result)).toBe("2026-08-17T11:00");
  });
});