/**
 * Тесты редьюсера тач-ввода: вся таблица переходов.
 * tap → pixelToPoint; pending/commit/cancel/перенос по контракту.
 */
import { describe, expect, it } from 'vitest';
import type { Point } from '@go-learn/core';
import { computeGeometry, pointToPixel } from './geometry.js';
import type { InputEvent, InputState } from './input.js';
import { reduceInput } from './input.js';

const geo = computeGeometry(9, 450, false);
const IDLE: InputState = { pending: null };

function tap(point: Point): InputEvent {
  const { x, y } = pointToPixel(geo, point);
  return { type: 'tap', px: x, py: y };
}

const A: Point = { x: 3, y: 3 };
const B: Point = { x: 5, y: 6 };

describe('reduceInput: tap', () => {
  it('тап при pending=null → pending=точка, commit=null', () => {
    const result = reduceInput(IDLE, tap(A), geo);
    expect(result.commit).toBeNull();
    expect(result.state.pending).toEqual(A);
  });

  it('повторный тап по той же точке → commit=точка, pending=null', () => {
    const result = reduceInput({ pending: A }, tap(A), geo);
    expect(result.commit).toEqual(A);
    expect(result.state.pending).toBeNull();
  });

  it('тап по другой точке → перенос pending, commit=null', () => {
    const result = reduceInput({ pending: A }, tap(B), geo);
    expect(result.commit).toBeNull();
    expect(result.state.pending).toEqual(B);
  });

  it('тап мимо доски → состояние не меняется, commit=null', () => {
    const miss: InputEvent = { type: 'tap', px: -20, py: 450 + 20 };
    const fromIdle = reduceInput(IDLE, miss, geo);
    expect(fromIdle.state).toBe(IDLE);
    expect(fromIdle.commit).toBeNull();
    const withPending: InputState = { pending: A };
    const fromPending = reduceInput(withPending, miss, geo);
    expect(fromPending.state).toBe(withPending);
    expect(fromPending.commit).toBeNull();
  });
});

describe('reduceInput: confirm', () => {
  it('confirm при pending → commit=pending, pending=null', () => {
    const result = reduceInput({ pending: A }, { type: 'confirm' }, geo);
    expect(result.commit).toEqual(A);
    expect(result.state.pending).toBeNull();
  });

  it('confirm без pending → commit=null, pending=null', () => {
    const result = reduceInput(IDLE, { type: 'confirm' }, geo);
    expect(result.commit).toBeNull();
    expect(result.state.pending).toBeNull();
  });
});

describe('reduceInput: cancel', () => {
  it('cancel при pending → сброс, commit=null', () => {
    const result = reduceInput({ pending: A }, { type: 'cancel' }, geo);
    expect(result.commit).toBeNull();
    expect(result.state.pending).toBeNull();
  });

  it('cancel без pending → commit=null, pending=null', () => {
    const result = reduceInput(IDLE, { type: 'cancel' }, geo);
    expect(result.commit).toBeNull();
    expect(result.state.pending).toBeNull();
  });
});