import { afterEach, beforeEach, describe, expect, it, vi } from 'vitest';
import { PalmRejector } from './palm';

const ev = (type: string, pointerType: string, extra: Partial<PointerEvent> = {}) =>
	({ type, pointerType, pointerId: pointerType === 'pen' ? 1 : 2, width: 10, height: 10, ...extra }) as PointerEvent;
const touch = (extra: Partial<PointerEvent> = {}) => ev('pointerdown', 'touch', extra);

describe('palm rejection', () => {
	beforeEach(() => vi.useFakeTimers());
	afterEach(() => vi.useRealTimers());

	/** Pen writes a stroke, hovers, then leaves range; `ms` later a finger lands. */
	function afterPen(ms: number, { leave = true } = {}) {
		const palm = new PalmRejector();
		for (const t of ['pointermove', 'pointerdown', 'pointermove', 'pointerup', 'pointermove']) palm.track(ev(t, 'pen'));
		if (leave) palm.track(ev('pointerleave', 'pen'));
		vi.advanceTimersByTime(ms);
		return palm;
	}

	it('accepts fingers before any pen is used', () => {
		const palm = new PalmRejector();
		expect(palm.penSeen).toBe(false);
		expect(palm.evaluate(touch(), 'draw').accept).toBe(true);
	});

	it('rejects every touch while the pen is down', () => {
		const palm = new PalmRejector();
		palm.track(ev('pointerdown', 'pen'));
		vi.advanceTimersByTime(1000);
		expect(palm.evaluate(touch(), 'navigate').accept).toBe(false);
		expect(palm.evaluate(touch(), 'draw').accept).toBe(false);
	});

	it('lets fingers navigate between pen strokes but not draw', () => {
		const palm = afterPen(300);
		expect(palm.penSeen).toBe(true);
		expect(palm.evaluate(touch(), 'navigate').accept).toBe(true);
		expect(palm.evaluate(touch(), 'draw')).toEqual({ accept: false, reason: 'pen session active' });
	});

	it('lets fingers navigate while the pen hovers, but not draw', () => {
		const palm = afterPen(6000, { leave: false });
		expect(palm.evaluate(touch(), 'navigate').accept).toBe(true);
		expect(palm.evaluate(touch(), 'draw')).toEqual({ accept: false, reason: 'pen hovering' });
	});

	it('still rejects palms and touches right after the pen', () => {
		expect(afterPen(50).evaluate(touch(), 'navigate').accept).toBe(false);
		expect(afterPen(300).evaluate(touch({ width: 60, height: 60 }), 'navigate').accept).toBe(false);
	});

	it('allows finger ink again once the pen session ends', () => {
		expect(afterPen(5100).evaluate(touch(), 'draw').accept).toBe(true);
	});
});