import {
	formatBytes,
	formatClock,
	formatCount,
	formatDuration,
	formatMicros,
	formatPercent,
	formatRate,
	formatTime,
} from "@/lib/format";

test("formatTime renders unix seconds in the given locale and zone", () => {
	// 2024-01-01T00:00:00Z; ICU emits U+202F before AM/PM in recent Node.
	expect(formatTime(1704067200, "en-US", "UTC").replace(/\u202f/g, " ")).toBe("Jan 1, 2024, 12:00:00 AM");
});

test("formatClock states the time of day alone, for a stamp read against now", () => {
	expect(formatClock(Date.UTC(2026, 0, 1, 14, 5) / 1000, "en-GB", "UTC")).toBe("14:05");
	expect(formatClock(Date.UTC(2026, 0, 1, 9, 30) / 1000, "en-GB", "UTC")).toBe("09:30");
	// No date: the caller places it against now, and a date would be noise.
	expect(formatClock(Date.UTC(2026, 0, 1, 14, 5) / 1000, "en-GB", "UTC")).not.toMatch(/2026/);
});

test("formatCount groups thousands", () => {
	expect(formatCount(0)).toBe("0");
	expect(formatCount(999)).toBe("999");
	expect(formatCount(18432)).toBe("18,432");
	expect(formatCount(1_234_567)).toBe("1,234,567");
});

test("formatPercent always carries two decimals, rounded half up", () => {
	expect(formatPercent(0)).toBe("0.00%");
	expect(formatPercent(1)).toBe("100.00%");
	expect(formatPercent(0.1544)).toBe("15.44%");
	expect(formatPercent(0.154)).toBe("15.40%");
	// A stored 15.435 sits just under the half; it still rounds up.
	expect(formatPercent(0.15435)).toBe("15.44%");
	expect(formatPercent(0.15434)).toBe("15.43%");
	expect(formatPercent(0.005)).toBe("0.50%");
	expect(formatPercent(0.00005)).toBe("0.01%");
	expect(formatPercent(0.00004)).toBe("0.00%");
});

test("formatRate carries one decimal, rounded half up", () => {
	expect(formatRate(12.84)).toBe("12.8");
	expect(formatRate(12.85)).toBe("12.9");
	expect(formatRate(5)).toBe("5.0");
	expect(formatRate(0)).toBe("0.0");
});

test("formatBytes humanizes with binary units", () => {
	expect(formatBytes(0)).toBe("0 B");
	expect(formatBytes(1023)).toBe("1023 B");
	expect(formatBytes(1024)).toBe("1.0 KiB");
	expect(formatBytes(1536)).toBe("1.5 KiB");
	expect(formatBytes(5 * 1024 * 1024)).toBe("5.0 MiB");
	expect(formatBytes(3 * 1024 * 1024 * 1024)).toBe("3.0 GiB");
	expect(formatBytes(2 * 1024 ** 4)).toBe("2.0 TiB");
});

test("formatDuration is the two largest nonzero units, unpadded", () => {
	expect(formatDuration(45)).toBe("45s");
	expect(formatDuration(60)).toBe("1m");
	expect(formatDuration(725)).toBe("12m 5s");
	expect(formatDuration(3600)).toBe("1h");
	expect(formatDuration(3600 * 4 + 60 * 12 + 30)).toBe("4h 12m");
	expect(formatDuration(86400 * 6 + 3600 * 4)).toBe("6d 4h");
	// The two largest that are nonzero, whatever sits between them.
	expect(formatDuration(86400 * 6 + 5)).toBe("6d 5s");
	expect(formatDuration(86400 * 6)).toBe("6d");
	expect(formatDuration(86400 * 400)).toBe("400d");
	// Never "06d 4h" or "6d 04h".
	expect(formatDuration(86400 * 6 + 3600 * 4)).not.toMatch(/0\d/);
});

test("formatDuration reads under a second as such, skew included", () => {
	expect(formatDuration(0)).toBe("<1s");
	expect(formatDuration(0.9)).toBe("<1s");
	expect(formatDuration(-5)).toBe("<1s");
});

test("formatMicros renders milliseconds with one decimal", () => {
	expect(formatMicros(0)).toBe("0.0 ms");
	expect(formatMicros(1234)).toBe("1.2 ms");
	expect(formatMicros(999)).toBe("1.0 ms");
	expect(formatMicros(2_500_000)).toBe("2500.0 ms");
});

/**
 * The contract's teeth, as far as a text scan can bite: no source outside this
 * module calls a number-formatting API. A bare `{count}` in JSX is invisible to
 * this scan and is caught in review; the scan closes the door on the four ways
 * a competing rule would be written. `datetime-local` zero-padding in
 * `activity/datetime.ts` is a wire grammar, not a display rule, and is the one
 * allowed `padStart`. Identifiers, configured values and preset labels are not
 * quantities at all and are exempt by the header rule, so the scan never sees
 * them.
 */
test("no source file outside format.ts calls a number-formatting API", () => {
	const sources = import.meta.glob<string>("../**/*.{ts,tsx}", { query: "?raw", import: "default", eager: true });
	const offenders: string[] = [];
	for (const [path, text] of Object.entries(sources)) {
		if (/\.test\.tsx?$/.test(path) || /(^|\/)format\.ts$/.test(path)) continue;
		for (const pattern of [/\.toFixed\(/, /\.toLocaleString\(/, /Intl\.NumberFormat/]) {
			if (pattern.test(text)) offenders.push(`${path}: ${pattern.source}`);
		}
		if (/\.padStart\(/.test(text) && !path.endsWith("/activity/datetime.ts")) offenders.push(`${path}: padStart`);
	}
	expect(Object.keys(sources).length).toBeGreaterThan(50);
	expect(offenders).toEqual([]);
});