import { Container } from 'pixi.js';
import { describe, expect, it } from 'vitest';
import { TextPool } from '../../src/ui/textPool';

describe('a pool of texts', () => {
  it('makes a text for each wanted string, in their order', () => {
    const layer = new Container();
    const shown = new TextPool(layer).show(['0', '1', '2']);
    expect(shown.map((t) => t.text)).toEqual(['0', '1', '2']);
    expect(layer.children).toHaveLength(3);
  });

  it('keeps a text on the string it shows, so a pan sets only the new one', () => {
    const pool = new TextPool(new Container());
    const [, one, two] = pool.show(['0', '1', '2']);
    const before = pool.changes;
    const shown = pool.show(['1', '2', '3']);
    expect(shown[0]).toBe(one);
    expect(shown[1]).toBe(two);
    expect(shown.map((t) => t.text)).toEqual(['1', '2', '3']);
    expect(pool.changes - before).toBe(1);
  });

  it('hides the texts not wanted and makes no more than it needs', () => {
    const layer = new Container();
    const pool = new TextPool(layer);
    pool.show(['a', 'b', 'c']);
    const [kept] = pool.show(['b']);
    expect(kept!.text).toBe('b');
    expect(layer.children.filter((t) => t.visible)).toEqual([kept]);
    pool.show(['x', 'y', 'z']);
    expect(layer.children).toHaveLength(3);
    expect(layer.children.every((t) => t.visible)).toBe(true);
  });

  it('gives a string wanted twice two texts', () => {
    const pool = new TextPool(new Container());
    pool.show(['…', '…']);
    const shown = pool.show(['…', '…']);
    expect(new Set(shown).size).toBe(2);
    expect(pool.changes).toBe(2);
  });
});