import { describe, expect, test } from "bun:test";
import {
	INSTANT_WIDGET_LAYOUT_SIZE_TRANSITION,
	isWidgetLayoutCubicBezier,
	toInstantWidgetLayoutSizeUpdate,
	toTimedWidgetLayoutSizeTransition,
	toTimedWidgetLayoutSizeUpdate,
} from "./widget-layout-size-update.js";

describe("widget layout size update", () => {
	test("wraps a host size in the current instant transition contract", () => {
		expect(
			toInstantWidgetLayoutSizeUpdate({ width: 320, height: 240 }),
		).toEqual({
			size: { width: 320, height: 240 },
			transition: {
				kind: "instant",
				durationMs: 0,
			},
		});
	});

	test("shares the zero-duration transition constant", () => {
		expect(
			toInstantWidgetLayoutSizeUpdate({ width: 1, height: 1 }).transition,
		).toBe(INSTANT_WIDGET_LAYOUT_SIZE_TRANSITION);
	});

	test("keeps the existing size update contract instant-only", () => {
		const update = toInstantWidgetLayoutSizeUpdate({ width: 320, height: 240 });

		expect(update.transition.kind).toBe("instant");
	});

	test("wraps a host size in the timed transition contract", () => {
		expect(
			toTimedWidgetLayoutSizeUpdate({
				size: { width: 320, height: 240 },
				durationMs: 180,
				easing: [0.2, 0, 0, 1],
			}),
		).toEqual({
			size: { width: 320, height: 240 },
			transition: {
				kind: "timed",
				durationMs: 180,
				easing: {
					kind: "cubic-bezier",
					points: [0.2, 0, 0, 1],
				},
			},
		});
	});

	test("accepts cubic-bezier y control point overshoot", () => {
		expect(isWidgetLayoutCubicBezier([0.34, -0.2, 0.64, 1.35])).toBe(true);
		expect(
			toTimedWidgetLayoutSizeTransition({
				durationMs: 220,
				easing: [0.34, -0.2, 0.64, 1.35],
			}).easing.points,
		).toEqual([0.34, -0.2, 0.64, 1.35]);
	});

	test("fails closed for non-array cubic-bezier input", () => {
		expect(isWidgetLayoutCubicBezier(null)).toBe(false);
		expect(isWidgetLayoutCubicBezier({ 0: 0.2, 1: 0, 2: 0, 3: 1 })).toBe(false);
		expect(isWidgetLayoutCubicBezier("0.2,0,0,1")).toBe(false);
	});

	test("rejects cubic-bezier x control points outside normalized time", () => {
		expect(isWidgetLayoutCubicBezier([-0.01, 0, 0.5, 1])).toBe(false);
		expect(isWidgetLayoutCubicBezier([0.5, 0, 1.01, 1])).toBe(false);
		expect(() =>
			toTimedWidgetLayoutSizeTransition({
				durationMs: 220,
				easing: [-0.01, 0, 0.5, 1],
			}),
		).toThrow(RangeError);
	});

	test("rejects invalid timed transition duration", () => {
		expect(() =>
			toTimedWidgetLayoutSizeTransition({
				durationMs: 0,
				easing: [0.2, 0, 0, 1],
			}),
		).toThrow(RangeError);
	});
});