// 用真实引擎（Player/Level）测量跳跃水平距离，核对求解器的物理近似是否可信
const handlers = {};
const addL = (t, fn) => { (handlers[t] = handlers[t] || []).push(fn); };
globalThis.addEventListener = addL;
globalThis.window = { addEventListener: addL };
const key = (t, c) => (handlers[t] || []).forEach(fn => fn({ code: c, preventDefault() { }, repeat: false }));

const { Level } = await import('../js/level.js');
const { Player } = await import('../js/player.js');
const { Input } = await import('../js/input.js');

// 一块 40 格长的平地，右端断开
const flat = {
  id: 'test', name: 'T', type: 'jump', width: 44,
  grid: (() => {
    const rows = [];
    rows.push('#'.repeat(44));
    for (let i = 0; i < 16; i++) rows.push('#' + '.'.repeat(42) + '#');
    rows.push('#' + '#'.repeat(42) + '#');                     // 整条实心平台
    rows.push('#'.repeat(44));
    return rows;
  })(),
};

function measure(djFrame) {
  const L = new Level(flat);
  const P = new Player(L);
  P.x = 8 * 32; P.y = 16 * 32 - P.h;   // 站在 row17 平台上（平台行 17）
  P.vx = 0; P.vy = 0; P.grounded = true; P.jumps = 0;
  const x0 = P.x;
  key('keydown', 'ArrowRight');
  key('keydown', 'ShiftLeft');
  let f = 0, landed = -1, released = false;
  for (let i = 0; i < 200; i++) {
    f++;
    // 二段跳需要先松开再按下（跨帧），否则不算一次新的按下
    if (djFrame && f === djFrame) { key('keyup', 'ShiftLeft'); released = true; }
    if (released && f === djFrame + 1) { key('keydown', 'ShiftLeft'); released = false; }
    L.update(1, P, null);
    P.update(1);
    Input.endFrame();
    if (i > 2 && P.grounded) { landed = P.x; break; }
    if (P.dead) break;
  }
  key('keyup', 'ArrowRight'); key('keyup', 'ShiftLeft');
  Input.endFrame();
  return { dist: landed >= 0 ? landed - x0 : null, f };
}

console.log('真实引擎跳跃水平距离（起跳点 x 到落点 x，单位 px / 格）');
for (const dj of [0, 6, 12, 18, 24, 30]) {
  const r = measure(dj);
  console.log(`  二段跳时机=${String(dj).padStart(2)} 帧 -> ${r.dist === null ? '未落地' : r.dist.toFixed(1) + 'px = ' + (r.dist / 32).toFixed(2) + ' 格 (' + r.f + ' 帧)'}`);
}