SoundGame/web/dungeon/game.js

/**
 * 《回声地窟》—— 纯音频听声辨位 Roguelike（按 docs/design/16-dungeon.md 实现；
 * 台词 id 见 16-dungeon-voice-ids.md，125 句 ×2 性别，无 NPC——怪物不说话）。
 *
 * 你是盲眼探窟者：单击=声波脉冲，回声"看"地形（正前距离 4 档 × 材质、左右侧
 * 墙/开口，全部预 pan 资产 + setTimeout + volume 调度，引擎外零实时节点——
 * playtest 虚拟时钟可逐项断言）；按住=前进（450ms 起、每格 0.5s、撞墙停无伤）；
 * 左右滑=转身；双击=免费重发脉冲；上滑=状态链；下滑=菜单（三件套不豁免）。
 *
 * 状态机：TITLE / DRILL / EXPLORE / BATTLE / DESCEND / SETTLE + MENU 挂起 overlay。
 * 7 层地窟程序生成：mulberry32((seed ^ (floor*0x9E3779B9))>>>0) 每层独立子种子，
 * 房间→L 型走廊（链式生成树）→起点/楼梯（BFS 最远房心）→宝物→怪（BFS≥3 安全区），
 * 教学局 L1 叠加硬约束（正前 2 格内墙 / 门怪 / 房内金币），拒绝采样保证可复现。
 * 战斗：缠斗/绕位/Boss 三档，前摇 1.2s 内双击格挡（面对 ×0.2 / 背后 ×1.0），
 * 逃跑长按必成挨一下（真话），Boss 拒绝；每 4 杀 atkLv+1。
 * 元进度"遗产"5 项（金币自动购置，死亡不清档）：行囊药/体魄/护符/回声强化/武器。
 * 死亡归因真话律：die_cause_* / die_adv_* 按 lastHit（击杀者/背刺/未格挡）与
 * run.parries 真实选择；卡关三级提示 60/120/180s（不报答案，L3 只带方向）。
 *
 * 豁免 E1-E4：单击=脉冲、长按=前进/左右滑=转身（E2）、对局期
 * setRateBoostEnabled(false)（E3，EXPLORE/BATTLE/DRILL/DESCEND，TITLE/MENU/SETTLE
 * 恢复 true）、战斗菜单=暂停（E4）。longpressend 仅作停走信号，不开 immediateTap。
 */

import { Game } from '../engine/game.js';
import { Guide } from '../engine/guide.js';
import { vibrate } from '../engine/haptics.js';

// ================================ 常量表 ================================

/** 绝对方位：DIR_ORDER 顺时针（右转 = idx+1，左转 = idx-1，N→W 为逆时针 ✓）。 */
const DIR_ORDER = ['N', 'E', 'S', 'W'];
const DIR_VEC = { N: { dx: 0, dy: -1 }, E: { dx: 1, dy: 0 }, S: { dx: 0, dy: 1 }, W: { dx: -1, dy: 0 } };
const DIR_KEY = { N: 'n', E: 'e', S: 's', W: 'w' };

/** 相对方位（战斗/脚步共用）：0 前 / 1 右 / 2 后 / 3 左。 */
const REL = { FRONT: 0, RIGHT: 1, BEHIND: 2, LEFT: 3 };

const PULSE_CD = 1200;          // 脉冲冷却（§3.1）
const TEL_WINDOW = 1200;        // 敌方攻击前摇 = 格挡窗口（§7.2）
const WALK_STEP_MS = 500;       // 长按每格耗时（§2.1）
const STUCK_LEVELS = [60000, 120000, 180000]; // 卡关三级（§10.3）
const NAV_REPEAT_MS = 60000;    // L3 带路重复周期
const NAV_MIN_GAP_MS = 1500;    // 同向导航句最小间隔（R2 D1-3：短窗不重复，保险丝友好）
const DENSITY_STEP = 12;        // 主路径内容密度下限（R2 D0-3①）：每 ≤12 格必有遭遇
const AMB_AFTER_MS = 20000;     // 探索呼吸层（R2 D0-3②）：静默超 20s 播环境垫
const AMB_VOLUME = 0.35;

/** 回声编码（§3.1）：正前距离 4 档 → 延迟 / 音量。 */
const ECHO_DELAY = [0, 250, 500, 800, 1100];
const ECHO_VOL = [0, 0.9, 0.7, 0.5, 0.35];
const SIDE_AT = 350;            // 侧向回声延后
const MAT_TAIL_AT = 120;        // 材质尾音跟在回声到达后

/** 敌型表（§7.2/§8.1；def 全 0，cls=脚步/前摇音色类，gold=掉落）。 */
const MOBS = {
  bat:     { hp: 4,  atk: 0, def: 0, cls: 'small', gold: 3,  start: 'btl_bat' },
  rat:     { hp: 6,  atk: 1, def: 0, cls: 'small', gold: 5,  start: 'btl_rat' },
  mush:    { hp: 8,  atk: 2, def: 0, cls: 'bug',   gold: 8,  start: 'btl_mush' },
  crab:    { hp: 20, atk: 3, def: 0, cls: 'heavy', gold: 50, start: 'btl_crab', boss: true, mover: true, half: 'btl_half_crab' },
  crawler: { hp: 10, atk: 2, def: 0, cls: 'bug',   gold: 10, start: 'btl_crawler', mover: true },
  spider:  { hp: 12, atk: 3, def: 0, cls: 'bug',   gold: 12, start: 'btl_spider' },
  leech:   { hp: 26, atk: 4, def: 0, cls: 'heavy', gold: 80, start: 'btl_leech', boss: true, mover: true, half: 'btl_half_leech' },
  guard:   { hp: 16, atk: 4, def: 0, cls: 'heavy', gold: 15, start: 'btl_guard', mover: true },
  king:    { hp: 36, atk: 5, def: 0, cls: 'heavy', gold: 0,  start: 'btl_king', boss: true, mover: true, half: 'btl_half_king' },
};

/** 层规格（§6.2）：尺寸 / 怪物（型×数）/ 宝物 / 窟主 / 终局。 */
const FLOOR_SPECS = {
  1: { size: 7,  mobs: { bat: 2 },                    items: ['coin'], drill: true },
  2: { size: 7,  mobs: { rat: 3 },                    items: ['coin', 'potion'] },
  3: { size: 9,  mobs: { mush: 3, crab: 1 },          items: ['coin', 'weapon1'], boss: 'crab' },
  4: { size: 9,  mobs: { crawler: 2, spider: 2 },     items: ['coin', 'armor1'] },
  5: { size: 11, mobs: { spider: 3, crawler: 2 },     items: ['coin', 'potion'] },
  6: { size: 11, mobs: { spider: 2, crawler: 2, leech: 1 }, items: ['coin', 'weapon2'], boss: 'leech' },
  7: { size: 11, mobs: { guard: 3, king: 1 },         items: ['coin'], final: true },
};

/** 元进度遗产（§7.4）：按价格升序自动购置（金币累计，死亡不清档）。 */
const LEGACIES = [
  { id: 'potion', price: 90, voice: 'unlock_potion' },
  { id: 'vigor', price: 150, voice: 'unlock_vigor' },
  { id: 'veil', price: 220, voice: 'unlock_veil' },
  { id: 'echo', price: 300, voice: 'unlock_echo' },
  { id: 'blade', price: 450, voice: 'unlock_blade' },
];

const MENU_ITEMS = ['sys_menu_resume', 'sys_menu_save', 'sys_menu_help', 'sys_menu_restart'];
const TITLE_MENU = ['sys_menu_help', 'sys_menu_resume']; // §2.3：标题/结算菜单（帮助/返回两项）

const HP_BAND_TEXT = { 1: '毫发无损', 2: '受了点伤', 3: '伤势不轻', 4: '命悬一线' };

const SAVE_KEY = 'soundgame.progress.dungeon';
const AUTH_KEY = 'soundgame.auth';

const PREWARM_SFX = [
  'sfx/pulse', 'sfx/echo_1', 'sfx/echo_2', 'sfx/echo_3', 'sfx/echo_4',
  'sfx/mat_stone', 'sfx/mat_door', 'sfx/mat_stair', 'sfx/mat_water',
  'sfx/side_wall_l', 'sfx/side_wall_r', 'sfx/side_open_l', 'sfx/side_open_r',
  'sfx/step_own', 'sfx/step_turn', 'sfx/bump',
  'sfx/coin', 'sfx/potion', 'sfx/gear', 'sfx/stairs_down',
  'sfx/mob_step_small_l', 'sfx/mob_step_small_c', 'sfx/mob_step_small_r',
  'sfx/mob_step_bug_l', 'sfx/mob_step_bug_c', 'sfx/mob_step_bug_r',
  'sfx/mob_step_heavy_l', 'sfx/mob_step_heavy_c', 'sfx/mob_step_heavy_r',
  'sfx/tel_small', 'sfx/tel_small_l', 'sfx/tel_small_r',
  'sfx/tel_bug', 'sfx/tel_bug_l', 'sfx/tel_bug_r',
  'sfx/tel_heavy', 'sfx/tel_heavy_l', 'sfx/tel_heavy_r',
  'sfx/atk_swing', 'sfx/atk_hit', 'sfx/parry', 'sfx/hurt', 'sfx/enemy_die', 'sfx/levelup',
  'sfx/amb_cave', 'sfx/turn_tick', // R2：探索呼吸层垫（D0-3②）+ 战斗回合确认音（D1-6）
];

// ================================ 工具 ================================

const key = (x, y) => x + ',' + y;
const range = (a, b) => { const r = []; const s = a <= b ? 1 : -1; for (let i = a; a <= b ? i <= b : i >= b; i += s) r.push(i); return r; };

// ================================ 主类 ================================

export class DungeonGame extends Game {
  constructor(audio, root, opts = {}) {
    super(audio, root);
    this.guide = new Guide(audio); // guide='off' 时全部 API 静默 no-op 且零定时器
    this._fixedSeed = opts.seed != null ? opts.seed : null; // playtest 注入（仅首个新周目生效）
    this.state = 'boot';       // TITLE / DRILL / EXPLORE / BATTLE / DESCEND / SETTLE
    this.menuOpen = false;     // MENU = 挂起 overlay（记录返回态 menuFrom）
    this.menuFrom = null;
    this._session = 0;         // 会话令牌：状态大跳转作废旧计时器
    this._timers = [];
    this.meta = this._defaultMeta();
    this.run = null;
    this._floor = null;
    this._battle = null;
    this._drill = null;
    this._walk = null;
    this._pulseAt = -1e9;
    this._lastHit = null;      // 归因真话律依据（击杀者/背刺/未格挡）
    this._lastEcho = null;     // 最近一次脉冲回声（双击重发一致性断言用）
    this._onStairs = false;
    this._stairsSpokenFloor = 0;
    this._dangerFloorDone = false;
    this._menuPause = null;
    this._menuItems = MENU_ITEMS;
    this._menuIdx = 0;
    this._stuck = { lastAct: 0, shown: new Set(), nav: false, lastFire: 0, pending: [] };
    this._stuckArmed = false;
    this._lastAmbAt = 0;       // 探索呼吸层上次播放时刻（R2 D0-3②）
    this._navLastDir = null;   // 导航模式上次播的方向（同向短窗节流，R2 D1-3）
    this._navLastAt = 0;
    this._titleChain = [];
  }

  _defaultMeta() {
    return { gold: 0, unlocks: [], bestFloor: 0, runs: 0, kills: 0, drillDone: false, pending: [] };
  }

  // ---------------- 派生数值（§8.1） ----------------

  _has(id) { return this.meta.unlocks.includes(id); }
  _maxHp() { return 20 + (this._has('vigor') ? 6 : 0); }
  _playerAtk() { return 2 + this.run.atkLv + this.run.weapon; }
  _armor() { return this.run.armor; }
  _hpBand(hp, max) {
    const r = hp / max;
    if (r > 0.75) return 1;
    if (r > 0.5) return 2;
    if (r > 0.25) return 3;
    return 4;
  }
  _goldBand(gold) { return gold < 50 ? 1 : gold <= 200 ? 2 : gold <= 600 ? 3 : 4; }

  // ================================ 地窟生成（§6） ================================

  /** seed 派生公式（§6.1，逐字照设计）：每层独立子种子。 */
  _floorSeedOf(seed, floor) {
    return (seed ^ (floor * 0x9E3779B9)) >>> 0;
  }

  _mulberry32(a) {
    return function () {
      a |= 0; a = (a + 0x6D2B79F5) | 0;
      let t = Math.imul(a ^ (a >>> 15), 1 | a);
      t = (t + Math.imul(t ^ (t >>> 7), 61 | t)) ^ t;
      return ((t ^ (t >>> 14)) >>> 0) / 4294967296;
    };
  }

  _bfs(grid, start) {
    const S = grid.length;
    const dist = Array.from({ length: S }, () => new Array(S).fill(-1));
    const q = [[start.x, start.y]];
    dist[start.y][start.x] = 0;
    while (q.length) {
      const [x, y] = q.shift();
      for (const d of Object.values(DIR_VEC)) {
        const nx = x + d.dx, ny = y + d.dy;
        if (nx < 0 || ny < 0 || nx >= S || ny >= S || grid[ny][nx] !== 1 || dist[ny][nx] >= 0) continue;
        dist[ny][nx] = dist[y][x] + 1;
        q.push([nx, ny]);
      }
    }
    return dist;
  }

  /**
   * 生成一层：外层拒绝采样（教学局 L1 硬约束优先于随机，§6.1 注），
   * 内层全走子种子 rng → 同 seed 两次构造逐格相等（§12.2）。
   * 走廊 = 相邻房间两两 L 型连通（链式 = 生成树，§6.1 ③ 的等价实现）。
   */
  _generateFloor(seed, floor) {
    const spec = FLOOR_SPECS[floor];
    const base = this._mulberry32(this._floorSeedOf(seed, floor));
    for (let attempt = 0; attempt < 80; attempt++) {
      const rng = this._mulberry32((base() * 4294967296) >>> 0);
      const f = this._tryGenFloor(rng, floor, spec);
      if (f) return f;
    }
    throw new Error(`dungeon: floor ${floor} generation failed (seed=${seed})`);
  }

  _tryGenFloor(rng, floor, spec) {
    const S = spec.size;
    const grid = Array.from({ length: S }, () => new Array(S).fill(0));
    const rooms = [];
    if (spec.drill) rooms.push({ x: 2, y: 2, w: 3, h: 3 }); // 教学房固定：起点恒 (3,3)
    const want = 3 + Math.floor(rng() * 4); // 3..6 间（§6.1 ②）
    for (let guard = 0; rooms.length < want && guard < 300; guard++) {
      const w = 2 + Math.floor(rng() * 2);            // 2..3
      const h = 2 + Math.floor(rng() * 3);            // 2..4
      const x = Math.floor(rng() * (S - w + 1));
      const y = Math.floor(rng() * (S - h + 1));
      if (rooms.some((r) => x < r.x + r.w && r.x < x + w && y < r.y + r.h && r.y < y + h)) continue; // 不重叠
      rooms.push({ x, y, w, h });
    }
    if (rooms.length < 3) return null;
    for (const r of rooms) {
      for (let yy = r.y; yy < r.y + r.h; yy++) for (let xx = r.x; xx < r.x + r.w; xx++) grid[yy][xx] = 1;
    }
    const centerOf = (r) => ({ x: r.x + (r.w >> 1), y: r.y + (r.h >> 1) });
    const carve = (x, y) => { if (x >= 0 && y >= 0 && x < S && y < S) grid[y][x] = 1; };
    for (let i = 1; i < rooms.length; i++) { // L 型走廊链式连通（§6.1 ③）
      const a = centerOf(rooms[i - 1]);
      const b = centerOf(rooms[i]);
      if (rng() < 0.5) {
        for (const x of range(a.x, b.x)) carve(x, a.y);
        for (const y of range(a.y, b.y)) carve(b.x, y);
      } else {
        for (const y of range(a.y, b.y)) carve(a.x, y);
        for (const x of range(a.x, b.x)) carve(x, b.y);
      }
    }
    const start = spec.drill ? { x: 3, y: 3 } : centerOf(rooms[0]);
    if (spec.drill) {
      carve(5, 3); // 东侧走道：D4 长按前进 ≥2 格后撞边界 bump
      carve(3, 5); // 南门：教学怪把门（D8 走向它触发战斗）
      if (grid[1][3] !== 0) return null; // 约束①：起点正前 2 格内有墙（D1 回声演示）
      if (grid[2][3] !== 1 || grid[4][3] !== 1) return null;
    }
    const dist = this._bfs(grid, start);
    const floorCells = [];
    for (let y = 0; y < S; y++) for (let x = 0; x < S; x++) {
      if (grid[y][x] === 1) {
        if (dist[y][x] < 0) return null; // 连通性不变式
        floorCells.push({ x, y, d: dist[y][x] });
      }
    }
    // 楼梯 = BFS 距起点最远房间中心（§6.1 ④）；终局层无楼梯，王座=最远房心
    let far = null, farD = -1;
    for (const r of rooms) {
      const c = centerOf(r);
      if (dist[c.y][c.x] > farD) { farD = dist[c.y][c.x]; far = c; }
    }
    const stairs = spec.final ? null : { x: far.x, y: far.y };
    const throne = spec.final ? { x: far.x, y: far.y } : null;
    // 宝物撒入房间格（§6.1 ⑤）
    const items = new Map();
    const occupied = new Set([key(start.x, start.y)]);
    if (stairs) occupied.add(key(stairs.x, stairs.y));
    if (throne) occupied.add(key(throne.x, throne.y));
    for (const it of spec.items) {
      let placed = null;
      for (let g2 = 0; g2 < 120 && !placed; g2++) {
        let c;
        if (spec.drill && it === 'coin') {
          // 约束③：教学金币固定在起点房内（拾取体验）
          const cells = [];
          for (let yy = 2; yy <= 4; yy++) for (let xx = 2; xx <= 4; xx++) {
            if (!(xx === 3 && yy === 3) && grid[yy][xx] === 1) cells.push({ x: xx, y: yy });
          }
          if (!cells.length) return null;
          c = cells[Math.floor(rng() * cells.length)];
        } else {
          const room = rooms[Math.floor(rng() * rooms.length)];
          c = { x: room.x + Math.floor(rng() * room.w), y: room.y + Math.floor(rng() * room.h) };
        }
        if (grid[c.y]?.[c.x] !== 1 || dist[c.y][c.x] < 1 || occupied.has(key(c.x, c.y))) continue;
        placed = c;
      }
      if (!placed) return null;
      occupied.add(key(placed.x, placed.y));
      items.set(key(placed.x, placed.y), it === 'coin'
        ? { type: 'coin', gold: 10 + Math.floor(rng() * 21) } // 堆 10-30 金（§7.4 经济核算）
        : { type: it });
    }
    // 怪物：窟主守楼梯格 / 终局王座；普通怪 BFS ≥3 安全区（教学局非门怪 ≥4，
    // 避免 D4/D8 演练路径撞上第二只怪）
    const mobs = [];
    const mobTypes = [];
    for (const [type, n] of Object.entries(spec.mobs)) for (let i = 0; i < n; i++) mobTypes.push(type);
    for (let i = mobTypes.length - 1; i > 0; i--) {
      const j = Math.floor(rng() * (i + 1));
      [mobTypes[i], mobTypes[j]] = [mobTypes[j], mobTypes[i]];
    }
    let doorBatPlaced = false;
    const minMobDist = spec.drill ? 4 : 3;
    for (const type of mobTypes) {
      const ms = MOBS[type];
      let cell = null;
      let isDoorBat = false;
      if (ms.boss) cell = spec.final ? { ...throne } : { ...stairs };
      else if (spec.drill && type === 'bat' && !doorBatPlaced) { cell = { x: 3, y: 5 }; isDoorBat = true; doorBatPlaced = true; }
      if (!cell) {
        for (let g3 = 0; g3 < 150 && !cell; g3++) {
          const c = floorCells[Math.floor(rng() * floorCells.length)];
          if (c.d < minMobDist || occupied.has(key(c.x, c.y))) continue;
          cell = { x: c.x, y: c.y };
        }
        if (!cell) return null;
      }
      occupied.add(key(cell.x, cell.y));
      mobs.push({ type, x: cell.x, y: cell.y, hp: ms.hp, maxHp: ms.hp, drill: isDoorBat });
    }
    this._fillMainPathDensity(spec, { grid, dist, start, stairs, throne, mobs, occupied, rng, minMobDist });
    return { floor, size: S, grid, rooms, start, stairs, throne, items, mobs, dist };
  }

  /**
   * 主路径内容密度下限（R2 D0-3①）：start→楼梯（终局层=王座）的最短路上每
   * ≤ DENSITY_STEP 格必有内容遭遇（怪/宝/楼梯/起点）。生成后沿 BFS 距离梯度
   * 回溯最短路，最长连续无内容段超限 → 段中点补一只本层已有的普通怪型
   * （结构性密度，不加新怪种；教学局补的仍是 ATK0 蝠）。确定性：只用同一 rng。
   */
  _fillMainPathDensity(spec, ctx) {
    const { grid, dist, start, stairs, throne, mobs, occupied, rng, minMobDist } = ctx;
    const goal = spec.final ? throne : stairs;
    if (!goal) return;
    const S = grid.length;
    const path = [{ x: goal.x, y: goal.y }];
    let cur = { x: goal.x, y: goal.y };
    while (cur.x !== start.x || cur.y !== start.y) { // 距离梯度回溯 = 最短路（固定扫描序，确定）
      for (const d of Object.values(DIR_VEC)) {
        const nx = cur.x + d.dx, ny = cur.y + d.dy;
        if (nx < 0 || ny < 0 || nx >= S || ny >= S || grid[ny][nx] !== 1 || dist[ny][nx] !== dist[cur.y][cur.x] - 1) continue;
        cur = { x: nx, y: ny };
        break;
      }
      path.push(cur);
    }
    const extraTypes = Object.keys(spec.mobs).filter((t) => !MOBS[t].boss);
    for (let round = 0; round < 8 && extraTypes.length; round++) {
      let bestA = -1, bestLen = 0, runA = 0;
      for (let i = 0; i <= path.length; i++) {
        const filled = i < path.length && occupied.has(key(path[i].x, path[i].y));
        if (!filled) continue; // 段在内容格（或路径尽头）闭合
        if (i - runA > bestLen) { bestLen = i - runA; bestA = runA; }
        runA = i + 1;
      }
      if (bestLen <= DENSITY_STEP) return; // 密度达标
      let mid = bestA + (bestLen >> 1);
      while (mid < path.length - 1 && dist[path[mid].y][path[mid].x] < minMobDist) mid++; // 安全区内偏后
      const cell = path[mid];
      if (dist[cell.y][cell.x] < minMobDist || occupied.has(key(cell.x, cell.y))) return; // 放不下：保底放弃
      const type = extraTypes[round % extraTypes.length];
      const ms = MOBS[type];
      occupied.add(key(cell.x, cell.y));
      mobs.push({ type, x: cell.x, y: cell.y, hp: ms.hp, maxHp: ms.hp, drill: false });
    }
  }

  /** 进入/重生成一层（下潜、读档重放共用）；已拾宝物与已清窟主按 run 过滤。 */
  _enterFloor(floor) {
    const r = this.run;
    r.floor = floor;
    this._floor = this._generateFloor(r.seed, floor);
    r.pos = { ...this._floor.start };
    r.face = 'N';
    r.veilUsedFloor = false;
    this._dangerFloorDone = false;
    this._pulseAt = -1e9;
    this._onStairs = false;
    this._stairsSpokenFloor = 0;
    for (const k of r.looted) this._floor.items.delete(k);
    if (FLOOR_SPECS[floor].boss && r.cleared.includes(floor)) {
      this._floor.mobs = this._floor.mobs.filter((m) => !MOBS[m.type].boss);
    }
  }

  // ================================ 生命周期 ================================

  start() {
    this.audio.prewarm(PREWARM_SFX);
    const save = this._loadSave();
    if (save) {
      this.meta = { ...this._defaultMeta(), ...save.meta, unlocks: [...(save.meta?.unlocks || [])], pending: [...(save.meta?.pending || [])] };
      if (save.run) {
        this.run = { ...save.run, pos: { x: save.run.pos[0], y: save.run.pos[1] } };
      }
    }
    this._enterTitle();
  }

  stop() {
    this._session++;
    this._clearTimers();
    this._stopWalk();
    this.audio.stopAll();
  }

  _goHome() {
    this.stop();
    window.location.href = '../';
  }

  // ---------------- TITLE（§2.3） ----------------

  _enterTitle() {
    this._session++;
    this._clearTimers();
    this._stopWalk();
    this._battle = null;
    this.menuOpen = false;
    this.menuFrom = null;
    this.state = 'TITLE';
    this.audio.stopVoice();
    this.audio.setRateBoostEnabled(true); // E3：非对局恢复长按快进
    this.audio.play('bgm/menu');
    this.guide.state('menu');
    this._titleChain = this.run ? ['voice/sys_continue_ask'] : [];
    if (this._titleChain.length) this._speak(this._titleChain);
  }

  _titleUpChain() {
    const ids = ['voice/meta_gold_' + this._goldBand(this.meta.gold)];
    const best = this.meta.bestFloor;
    ids.push(best < 3 ? 'voice/st_best_1' : best < 6 ? 'voice/st_best_2' : 'voice/st_best_3');
    if (this.meta.unlocks.length === 0) ids.push('voice/unlock_none');
    else for (const u of this.meta.unlocks) ids.push('voice/unlock_' + u);
    return ids;
  }

  _onTitleGesture(g) {
    if (g === 'tap') {
      if (this.run) this._resumeRun();
      else this._newRunFlow();
    } else if (g === 'right') {
      this._newRunFlow(); // 重掷新周目（meta 保留，§2.3）
    } else if (g === 'doubletap') {
      const chain = this._titleChain.length ? this._titleChain : this._titleUpChain();
      this._speak(chain); // 重听 continue_ask / 元进度播报
    } else if (g === 'up') {
      this._titleChain = this._titleUpChain();
      this._speak(this._titleChain);
    } else if (g === 'down') {
      this._openMenu();
    } else {
      this.guide.error({ voice: 'gd_invalid', onceKey: 'dungeon_invalid' }); // error 震 + full 档纠错
    }
  }

  // ---------------- 新周目 / 继续（§4.2、§11） ----------------

  _newRunFlow() {
    this._session++;
    this._clearTimers();
    this._stopWalk();
    this._battle = null;
    this._drill = null;
    this.menuOpen = false;
    this.audio.stopVoice();
    const seed = this._fixedSeed != null ? this._fixedSeed : Math.floor(Math.random() * 1e9);
    this._fixedSeed = null;
    this.run = {
      seed, floor: 1, pos: { x: 0, y: 0 }, face: 'N',
      hp: this._maxHp(), atkLv: 0,
      weapon: this._has('blade') ? 1 : 0, armor: 0,
      potion: this._has('potion') ? 1 : 0,
      veilUsedFloor: false, killsRun: 0, looted: [], cleared: [],
      parries: 0, flees: 0, gold: 0,
    };
    this._lastHit = null;
    this._enterFloor(1);
    this._save();
    const ids = ['voice/sys_new_run'];
    if (this.meta.pending.length) {
      ids.push('voice/unlock_lead');
      for (const u of this.meta.pending) ids.push('voice/unlock_' + u);
    }
    this._speakGuarded(ids, () => {
      this.meta.pending = [];
      this._save();
      if (!this.meta.drillDone) this._enterDrill();
      else this._resumeExplore(this._recapChain()); // 新周目直落探索也带局面复述（P3）
    }, 20000);
  }

  _restartRun(seed) { // 菜单"重新开始本周目"：同 seed 重置
    this.run = null;
    this._fixedSeed = seed;
    this._newRunFlow();
  }

  _recapChain() { // 局面复述（§11）：层 → 血量 → 面朝 → 威胁（金币只在显式上滑状态链）
    return ['voice/st_floor_' + this.run.floor,
      'voice/st_hp_' + this._hpBand(this.run.hp, this._maxHp()),
      'voice/st_face_' + DIR_KEY[this.run.face],
      'voice/st_threat_' + this._threatKey()];
  }

  _resumeRun() {
    const saved = { pos: { ...this.run.pos }, face: this.run.face, veil: this.run.veilUsedFloor };
    this._enterFloor(this.run.floor); // 重放该层 seed 生成（§11）
    this.run.pos = saved.pos;
    this.run.face = saved.face;
    this.run.veilUsedFloor = saved.veil;
    this._resumeExplore(this._recapChain());
  }

  // ================================ 状态接入 ================================

  /** 进入探索态（DRILL 完成后 / 战斗后 / 读档后共用）。chain = 前置语音链（可空）。 */
  _resumeExplore(chain) {
    this.state = 'EXPLORE';
    this._session++;
    this._clearTimers();
    this.menuOpen = false;
    this.audio.play('bgm/explore');
    this.audio.setRateBoostEnabled(false); // E3 豁免
    this.guide.state('explore');
    this._startMobs();
    this._stuck.lastAct = performance.now();
    this._lastAmbAt = performance.now(); // 呼吸层从进入探索起算静默（R2 D0-3②）
    this._stuckArm();
    this._armExploreWatchdog();
    if (chain && chain.length) this._speak(chain);
  }

  // ---------------- 手势总入口 ----------------

  onGesture(g) {
    this.guide.disarm(); // 任何手势复位向导看门狗（off 档 no-op）
    if (g === 'longpressend') { this._stopWalk(); return; } // 仅停走信号，不承载第二语义
    if (this.menuOpen) { this._onMenuGesture(g); return; }
    this._stuck.pending.length = 0; // 玩家操作即作废未播的卡关提示（§10.3）
    switch (this.state) {
      case 'TITLE': this._onTitleGesture(g); break;
      case 'DRILL': this._onDrillGesture(g); break;
      case 'EXPLORE': this._onExploreGesture(g); break;
      case 'BATTLE': this._onBattleGesture(g); break;
      case 'SETTLE': this._onSettleGesture(g); break;
      default: break; // DESCEND 演出窗口：不收手势
    }
    // 探索静止看门狗：每个手势后仍在探索态则重新武装（[10s, 25s] 两级）
    if (this.state === 'EXPLORE' && !this.menuOpen) this._armExploreWatchdog();
    if (this.state === 'EXPLORE' && !this.menuOpen) this._stuck.lastAct = performance.now();
  }

  // ================================ 探索态（§2.1） ================================

  _onExploreGesture(g) {
    if (g === 'tap') {
      if (this._onStairs && this._stairsUsable()) { this._descend(false); return; }
      this._pulse();
    } else if (g === 'doubletap') {
      this._pulse(); // 免费重发脉冲（同受 1.2s 冷却闸，§3.1）
    } else if (g === 'left') {
      this._turn(-1);
    } else if (g === 'right') {
      this._turn(1);
    } else if (g === 'up') {
      this._speakStatus();
    } else if (g === 'down') {
      this._openMenu();
    } else if (g === 'longpress') {
      this._startWalk();
    }
  }

  _stairsUsable() {
    const spec = FLOOR_SPECS[this.run.floor];
    if (!this._floor.stairs || !this._onStairs) return false;
    if (spec.boss && !this.run.cleared.includes(this.run.floor)) return false; // 窟主未清
    return true;
  }

  _turn(d) {
    const i = DIR_ORDER.indexOf(this.run.face);
    this.run.face = DIR_ORDER[(i + d + 4) % 4];
    this.audio.play('sfx/step_turn'); // swipe 震由 gesture.js 内置，不重复
  }

  /** 声波脉冲（§3.1）：全部预生成资产 + setTimeout + volume，可被虚拟时钟断言。 */
  _pulse() {
    const now = performance.now();
    if (now - this._pulseAt < PULSE_CD) { vibrate('error'); return null; } // 冷却期：仅 error 震
    this._pulseAt = now;
    this.audio.play('sfx/pulse', { volume: 0.8 });
    const s = this._session;
    const f = this._echoScan(this.run.pos.x, this.run.pos.y, this.run.face);
    const band = f.dist <= 1 ? 1 : f.dist === 2 ? 2 : f.dist <= 4 ? 3 : 4;
    const delay = ECHO_DELAY[band];
    const vol = ECHO_VOL[band];
    this._after(delay, () => { if (s === this._session) this.audio.play('sfx/echo_' + band, { volume: vol }); });
    this._after(delay + MAT_TAIL_AT, () => { if (s === this._session) this.audio.play('sfx/mat_' + f.mat, { volume: 0.8 }); });
    const L = this._sideScan(-1);
    const R = this._sideScan(1);
    this._after(SIDE_AT, () => {
      if (s !== this._session) return;
      this.audio.play('sfx/side_' + L.kind + '_l', { volume: this._sideVol(L) });
      this.audio.play('sfx/side_' + R.kind + '_r', { volume: this._sideVol(R) });
    });
    this._lastEcho = { band, dist: f.dist, mat: f.mat, left: L.kind, right: R.kind, delay, vol };
    return this._lastEcho;
  }

  /** 正前扫描：最近反射体决定距离与材质（楼梯=铁梯；身后方向永不进入扫描）。
   *  R2 D0-2：站在楼梯格上脉冲 → 贴身铁器回声（教学「铁器=楼梯」的兑现：
   *  R1 live 165 脉冲 0 次 mat_stair，连站在楼梯上都报石墙）。 */
  _echoScan(x, y, face) {
    const st = this._floor.stairs;
    if (st && x === st.x && y === st.y) return { dist: 1, mat: 'stair' };
    const d = DIR_VEC[face];
    const S = this._floor.size;
    for (let i = 1; i <= S * 2; i++) {
      const cx = x + d.dx * i, cy = y + d.dy * i;
      if (cx < 0 || cy < 0 || cx >= S || cy >= S || this._floor.grid[cy][cx] === 0) return { dist: i, mat: 'stone' };
      if (st && cx === st.x && cy === st.y) return { dist: i, mat: 'stair' };
      // 木门/水地形当前生成器不产出；材质表保留（mat_door/mat_water 供未来层）
    }
    return { dist: S * 2, mat: 'stone' };
  }

  /**
   * 侧向扫描（side = -1 左 / 1 右）：开口（第一格可通行=能走进去）/墙（闷，含距离），
   * 身后不报。R2 D0-2 重接 grid 单源：R1 旧实现把「整条侧射线到边界全通」才判
   * 开口——房间/走廊地型下恒为假，40+ 脉冲 side_open 0 次、明明能走的方向报墙。
   * 设计 §3.1 口径：侧向 2 档（墙=闷 / 开口=空旷回灵），开一格就是开口。
   */
  _sideScan(side) {
    const fi = DIR_ORDER.indexOf(this.run.face);
    const d = DIR_VEC[DIR_ORDER[(fi + side + 4) % 4]];
    const S = this._floor.size;
    let x = this.run.pos.x, y = this.run.pos.y;
    for (let i = 1; i <= S; i++) {
      x += d.dx; y += d.dy;
      if (x < 0 || y < 0 || x >= S || y >= S || this._floor.grid[y][x] === 0) {
        return { kind: 'wall', dist: i };
      }
      if (i === 1) return { kind: 'open', dist: 1 }; // 侧向第一格是地板 = 开口（真话）
    }
    return { kind: 'open', dist: S };
  }

  /** 侧向音量：回声强化解锁后按远近换 2 组资产音量（§7.4 unlock_echo）。 */
  _sideVol(s) {
    if (this._has('echo')) return s.dist <= 1 ? 0.8 : 0.45;
    return 0.6;
  }

  // ---------------- 长按前进（§2.1：450ms 起、每格 0.5s、撞墙停无伤） ----------------

  _startWalk() {
    if (this._walk || this.state !== 'EXPLORE' && this.state !== 'DRILL') return;
    if (this.menuOpen) return;
    this._walk = { steps: 0, bumped: false };
    this._walkStep();
  }

  _stopWalk() { this._walk = null; }

  _walkStep() {
    if (!this._walk) return;
    const s = this._session;
    const d = DIR_VEC[this.run.face];
    const nx = this.run.pos.x + d.dx;
    const ny = this.run.pos.y + d.dy;
    const S = this._floor.size;
    if (nx < 0 || ny < 0 || nx >= S || ny >= S || this._floor.grid[ny][nx] !== 1) {
      this.audio.play('sfx/bump'); // 撞墙：无伤自动停（§2.1）
      this._walk.bumped = true;
      this._afterWalkDrill();
      this._stopWalk();
      return;
    }
    this.run.pos = { x: nx, y: ny };
    this._walk.steps++;
    this.audio.play('sfx/step_own', { volume: 0.7 });
    vibrate('swipe');
    // 导航模式（卡关 L3）：每步播方向
    if (this._stuck.nav && this.state === 'EXPLORE') this._navSpeakStep();
    // 踏格判定：怪 → 遭遇；宝物 → 拾取；楼梯 → 提示/锁
    const mob = this._floor.mobs.find((m) => m.x === nx && m.y === ny);
    if (mob) { this._encounter(mob); return; } // _encounter 内部停走（session 令牌）
    const k = key(nx, ny);
    const item = this._floor.items.get(k);
    if (item) this._pickup(item, k);
    this._onStairCell(nx, ny);
    this._afterWalkDrill();
    this._after(WALK_STEP_MS, () => { if (s === this._session && this._walk) this._walkStep(); });
  }

  _afterWalkDrill() {
    const d = this._drill;
    if (!d || d.step !== 4 || !this._walk) return;
    if (this._walk.steps >= 2 || this._walk.bumped) this._drillPass(); // §5 D4：≥2 格（撞墙也算过）
  }

  _onStairCell(x, y) {
    const st = this._floor.stairs;
    if (!st || st.x !== x || st.y !== y) { this._onStairs = false; return; }
    this._onStairs = true;
    this._progress(); // 踏上楼梯格 = 进展事件（§10.3）
    const spec = FLOOR_SPECS[this.run.floor];
    if (spec.boss && !this.run.cleared.includes(this.run.floor)) {
      this._speak(['voice/evt_stairs_lock']);
      return;
    }
    if (this._stairsSpokenFloor !== this.run.floor) {
      this._stairsSpokenFloor = this.run.floor;
      this._speak(['voice/tut_stairs_on']); // 楼梯就在脚下。单击，下潜。
    }
  }

  // ---------------- 拾取（§6.2/§7.4） ----------------

  _pickup(item, k) {
    if (item.type === 'coin') {
      this.meta.gold += item.gold; // 金币实时入元进度（死亡不清档）
      this.run.gold += item.gold;
      this._floor.items.delete(k);
      this.run.looted.push(k);
      this.audio.play('sfx/coin');
      vibrate('pickup');
      const band = item.gold < 16 ? 1 : item.gold < 24 ? 2 : 3;
      this._speak(['voice/evt_coin_' + band]);
      this._progress();
      this._save();
    } else if (item.type === 'potion') {
      if (this.run.potion >= 1) {
        this._speak(['voice/evt_potion_full']); // 腰带满：药留在原地
        return;
      }
      this.run.potion = 1;
      this._floor.items.delete(k);
      this.run.looted.push(k);
      this.audio.play('sfx/potion');
      vibrate('pickup');
      this._speak(['voice/evt_potion']);
      this._progress();
      this._save();
    } else if (item.type === 'weapon1' || item.type === 'weapon2') {
      const lvl = item.type === 'weapon1' ? 1 : 2;
      if (this.run.weapon >= lvl) return; // 已有更优：留在原地
      this.run.weapon = lvl;
      this._floor.items.delete(k);
      this.run.looted.push(k);
      this.audio.play('sfx/gear');
      vibrate('pickup');
      this._speak(['voice/evt_weapon']);
      this._progress();
      this._save();
    } else if (item.type === 'armor1') {
      if (this.run.armor >= 1) return;
      this.run.armor = 1;
      this._floor.items.delete(k);
      this.run.looted.push(k);
      this.audio.play('sfx/gear');
      vibrate('pickup');
      this._speak(['voice/evt_armor']);
      this._progress();
      this._save();
    }
  }

  // ---------------- 状态播报（§2.1/§2.2/§3.2） ----------------

  _threatKey() {
    let left = 0, right = 0;
    const fi = DIR_ORDER.indexOf(this.run.face);
    for (const m of this._floor.mobs) {
      const dx = m.x - this.run.pos.x, dy = m.y - this.run.pos.y;
      if (Math.abs(dx) + Math.abs(dy) > 5) continue;
      const dirIdx = dx > 0 ? 1 : dx < 0 ? 3 : dy > 0 ? 2 : 0;
      const rel = (dirIdx - fi + 4) % 4;
      if (rel === REL.LEFT) left++;
      else if (rel === REL.RIGHT) right++;
      // 前方/身后不报（同回声降维，§3.2）
    }
    return left && right ? 'both' : left ? 'left' : right ? 'right' : 'none';
  }

  _speakStatus() { // 上滑：层 → 血量 → 金币 → 面朝 → 威胁（5 段链）
    const band = this._hpBand(this.run.hp, this._maxHp());
    if (band === 4) vibrate('warning');
    this._speak(['voice/st_floor_' + this.run.floor,
      'voice/st_hp_' + band,
      'voice/st_gold_' + this._goldBand(this.meta.gold),
      'voice/st_face_' + DIR_KEY[this.run.face],
      'voice/st_threat_' + this._threatKey()]);
  }

  // ================================ 怪物游走与遭遇（§7.1） ================================

  _startMobs() {
    for (const m of this._floor.mobs) {
      if (MOBS[m.type].boss) continue; // 窟主守楼梯格，不游走
      this._mobLoop(m);
    }
  }

  _mobLoop(m) {
    const s = this._session;
    this._after(1500 + Math.floor(Math.random() * 1000), () => {
      if (s !== this._session) return;
      if (this.state === 'EXPLORE' && !this.menuOpen) this._mobStep(m);
      this._mobLoop(m);
    });
  }

  _mobStep(m) {
    const S = this._floor.size;
    const opts = [];
    for (const d of Object.values(DIR_VEC)) {
      const nx = m.x + d.dx, ny = m.y + d.dy;
      if (nx >= 0 && ny >= 0 && nx < S && ny < S && this._floor.grid[ny][nx] === 1) opts.push({ x: nx, y: ny });
    }
    if (!opts.length) return;
    const into = opts.find((c) => c.x === this.run.pos.x && c.y === this.run.pos.y);
    if (into) { this._encounter(m); return; } // 怪走进你格
    const c = opts[Math.floor(Math.random() * opts.length)];
    m.x = c.x; m.y = c.y;
    this._mobStepSound(m.type, m.x, m.y);
    // R2 D1-3：相邻即开战（互视/贴身必扑）——杜绝 R1 live L3 蘑菇「贴身绕圈、
    // 堵格不开战」的软封锁；脚步+心跳预警在前，贴身必然接战（报名=它在面前）。
    if (Math.abs(m.x - this.run.pos.x) + Math.abs(m.y - this.run.pos.y) === 1) this._encounter(m);
  }

  /** 脚步报位（§7.1）：pan 按相对方位、音量按距离档；背后=中央资产音量减半。 */
  _mobStepSound(type, x, y) {
    const dx = x - this.run.pos.x, dy = y - this.run.pos.y;
    const dist = Math.abs(dx) + Math.abs(dy);
    if (dist > 8) return; // 更远不播
    const fi = DIR_ORDER.indexOf(this.run.face);
    const dirIdx = dx > 0 ? 1 : dx < 0 ? 3 : dy > 0 ? 2 : 0;
    const rel = (dirIdx - fi + 4) % 4;
    const pan = rel === REL.LEFT ? 'l' : rel === REL.RIGHT ? 'r' : 'c';
    let vol = dist <= 2 ? 0.9 : dist <= 4 ? 0.6 : 0.35;
    if (rel === REL.BEHIND) vol *= 0.5;
    this.audio.play('sfx/mob_step_' + MOBS[type].cls + '_' + pan, { volume: vol });
    if (dist <= 2) vibrate('heartbeat'); // 威胁前置预警窗（方法论 L2）
  }

  /** 遭遇（明雷 §7.1）：播报名即=它在面前（自动面对），BATTLE 三档。 */
  _encounter(mob) {
    this._stopWalk();
    const ms = MOBS[mob.type];
    this._floor.mobs = this._floor.mobs.filter((m) => m !== mob);
    this._session++;
    this._clearTimers();
    this._walk = null;
    this.state = 'BATTLE';
    this._battle = {
      type: mob.type, spec: ms, hp: mob.hp, maxHp: ms.hp, atk: ms.atk, def: ms.def,
      cls: ms.cls, boss: !!ms.boss, mover: !!ms.mover, cell: { x: mob.x, y: mob.y },
      bearing: DIR_ORDER.indexOf(this.run.face), moveN: 0, phase2: false,
      state: 'intro', windowEnd: 0, parry: false, noTurnSaid: false,
      drill: !!(this._drill && this._drill.step === 8),
      drillMob: !!mob.drill,
    };
    this.audio.play(ms.boss ? 'bgm/boss' : 'bgm/battle', { fadeMs: 400 });
    this.guide.state('battle');
    this._speakGuarded(['voice/' + ms.start], () => {
      if (this._battle?.drill) {
        // 教学战（§5 D8）：先由教学怪出手，练格挡
        this._speakGuarded(['voice/tut_parry'], () => this._enemyTurn(), 8000);
      } else {
        this._playerTurn();
      }
    }, 10000);
  }

  // ================================ 战斗（§7） ================================

  _battleRel() {
    return (this._battle.bearing - DIR_ORDER.indexOf(this.run.face) + 4) % 4;
  }

  _playerTurn() {
    const b = this._battle;
    if (!b) return;
    b.state = 'player';
    b.parry = false;
    this.guide.turn({ haptic: true }); // turn earcon + confirm 震（§10.2）
    this.guide.watchdog({
      arm: true, at: [15000, 30000], say: ['gd_turn', null],
      cond: () => this.state === 'BATTLE' && this._battle === b && b.state === 'player' && !this.menuOpen,
      onEscalate: (n) => { // R2 D1-6：15s 无操作播合成回执音（standard 档没有 gd_turn 语音也有"还到你"的确认）
        if (n === 1 && this.state === 'BATTLE' && !this.menuOpen) this.audio.play('sfx/turn_tick', { volume: 0.7 });
      },
    });
  }

  _onBattleGesture(g) {
    const b = this._battle;
    if (!b) return;
    if (b.state === 'player') {
      if (g === 'tap') this._swing();
      else if (g === 'doubletap') vibrate('error'); // 窗口外双击：error 震不生效（§7.2）
      else if (g === 'left') this._battleTurnG(-1);
      else if (g === 'right') this._battleTurnG(1);
      else if (g === 'longpress') this._flee();
      else if (g === 'up') this._speakBattleStatus();
      else if (g === 'down') this._openMenu();
    } else if (b.state === 'telegraph') {
      if (g === 'doubletap' && performance.now() <= b.windowEnd) {
        b.parry = true; // 面对与否在结算时按实际方位判（§7.2）；
        // parries 只在结算判成"面对且格挡成功"时计数（归因真话律：背对双击没挡下）
        this.audio.play('sfx/parry');
        vibrate('confirm');
      } else if (g === 'down') {
        this._openMenu(); // E4：战斗任意时刻可暂停——前摇内开菜单 → 冻结剩余窗口
      } else {
        vibrate('error'); // 窗口内做错手势 / 窗口已过：留在窗口不生效
      }
    }
    // 其他状态（intro/enemyMove/busy）：手势忽略
  }

  _swing() {
    const b = this._battle;
    b.state = 'busy';
    this.audio.play('sfx/atk_swing');
    if (this._battleRel() !== REL.FRONT) {
      // 挥空（归因真话，§2.2）：它不在你面前
      this._speakGuarded(['voice/btl_swish'], () => this._enemyTurn(), 6000);
      return;
    }
    this.audio.play('sfx/atk_hit');
    const dmg = Math.max(0, this._playerAtk() - b.def);
    b.hp -= dmg;
    if (b.hp <= 0) { this._victory(); return; }
    this._halfCheck(() => this._enemyTurn());
  }

  _halfCheck(next) {
    const b = this._battle;
    if (!b.phase2 && b.spec.half && b.hp <= b.maxHp / 2) {
      b.phase2 = true;
      b.atk += 1; // 半血 ATK+1（§7.2；王 5→6）
      this.guide.state('danger');
      vibrate('warning');
      this._speakGuarded(['voice/' + b.spec.half], next, 8000);
      return;
    }
    next();
  }

  /** 转身（战斗）：只对绕位怪/Boss 有意义；缠斗怪纠错（每场 1 次，§7.2）。 */
  _battleTurnG(d) {
    const b = this._battle;
    if (!b.mover) {
      vibrate('error');
      if (!b.noTurnSaid) {
        b.noTurnSaid = true;
        this._speakGuarded(['voice/btl_no_turn'], () => {}, 5000);
      }
      return;
    }
    const i = DIR_ORDER.indexOf(this.run.face);
    this.run.face = DIR_ORDER[(i + d + 4) % 4];
    this.audio.play('sfx/step_turn');
  }

  _speakBattleStatus() { // §2.2：我方血量档 → 敌方阶段 →（绕位/Boss）方位
    const b = this._battle;
    const band = this._hpBand(this.run.hp, this._maxHp());
    if (band === 4) vibrate('warning');
    const ids = ['voice/st_hp_' + band];
    if (b.spec.half && b.hp <= b.maxHp / 2) ids.push('voice/' + b.spec.half);
    if (b.mover) {
      const rel = this._battleRel();
      if (rel === REL.BEHIND) ids.push('voice/btl_behind');
      else if (rel === REL.LEFT) ids.push('voice/st_threat_left');
      else if (rel === REL.RIGHT) ids.push('voice/st_threat_right');
      // 正面：脚步/前摇音已报位，不占台词预算
    }
    this._speak(ids);
  }

  /** 长按=尝试逃跑（§7.3）：普通/绕位必成挨一下；Boss 拒绝。 */
  _flee() {
    const b = this._battle;
    if (b.boss) {
      vibrate('error');
      this._speakGuarded(['voice/btl_flee_boss'], () => this._playerTurn(), 5000);
      return;
    }
    b.state = 'busy';
    this.run.flees++;
    let dmg = Math.max(0, b.atk - this._armor()); // 撤退挨一下：真实账目，无格挡
    if (dmg > 0) {
      if (this._applyVeil()) dmg = Math.floor(dmg / 2);
      this.run.hp -= dmg;
      this.audio.play('sfx/hurt');
      vibrate('hit');
    }
    this._lastHit = { type: b.type, boss: b.boss, behind: false, parried: false, unparried: true, flee: true };
    if (this.run.hp <= 0) { this._die(); return; }
    const afterFlee = () => {
      this._battle = null;
      const restored = { type: b.type, x: b.cell.x, y: b.cell.y, hp: b.hp, maxHp: b.maxHp, drill: b.drillMob };
      this._floor.mobs.push(restored); // 怪留原格
      if (this._drill?.bat) this._drill.bat = restored;
      this._progress();
      this._save();
      if (this._drill) {
        this.state = 'DRILL';
        this.audio.play('bgm/explore', { fadeMs: 400 }); // R2 D1-4：教学战逃跑同样回探索曲
        if (this._drill.step === 8) this._drillApproach();
        return;
      }
      this._resumeExplore();
    };
    // 归因真话律：ATK0 怪（L1 蝠）根本没碰到你，「被抓了一下」是假话 → 静默脱战
    if (dmg > 0) this._speakGuarded(['voice/btl_flee'], afterFlee, 8000);
    else afterFlee();
  }

  /** 敌方回合：绕位怪每 2 回合移动（脚步报新方位）→ 攻击前摇 1.2s → 结算。 */
  _enemyTurn() {
    const b = this._battle;
    if (!b) return;
    b.state = 'enemyMove';
    b.parry = false;
    b.moveN++;
    if (b.mover && b.moveN % 2 === 0) {
      const seq = [REL.RIGHT, REL.BEHIND, REL.LEFT]; // 每 2 回合换位（确定性轮换）
      const rel = seq[(b.moveN / 2 - 1) % seq.length];
      b.bearing = (DIR_ORDER.indexOf(this.run.face) + rel) % 4;
      // 脚步报新方位（§7.2 绕位怪先移动）：pan 按相对方位，背后=中央资产音量减半
      const pan = rel === REL.LEFT ? 'l' : rel === REL.RIGHT ? 'r' : 'c';
      const vol = rel === REL.BEHIND ? 0.45 : 0.9;
      this.audio.play('sfx/mob_step_' + b.cls + '_' + pan, { volume: vol });
    }
    this._telegraph();
  }

  _telegraph() {
    const b = this._battle;
    b.state = 'telegraph';
    b.windowEnd = performance.now() + TEL_WINDOW;
    const rel = this._battleRel();
    const pan = rel === REL.LEFT ? '_l' : rel === REL.RIGHT ? '_r' : '';
    this.audio.play('sfx/tel_' + b.cls + pan);
    vibrate('beat'); // "格挡窗口已开"通道标识
    const s = this._session;
    this._after(TEL_WINDOW, () => {
      if (s === this._session && this._battle === b && b.state === 'telegraph') this._enemyResolve();
    });
  }

  _applyVeil() { // 护符：每层首次受击减半（§7.4）
    if (this._has('veil') && !this.run.veilUsedFloor) {
      this.run.veilUsedFloor = true;
      return true;
    }
    return false;
  }

  _enemyResolve() {
    const b = this._battle;
    b.state = 'resolve';
    const rel = this._battleRel();
    const facing = rel === REL.FRONT;
    const behind = rel === REL.BEHIND;
    let dmg = Math.max(0, b.atk - this._armor());
    const parried = b.parry && facing; // 面对攻击源 ×0.2，未面对 ×1.0（§2.2）
    if (parried) this.run.parries++; // 全程格挡数（§11）：只计真正挡下的（面对+窗口内）
    if (parried) dmg = Math.floor(dmg * 0.2);
    if (dmg > 0 && this._applyVeil()) dmg = Math.floor(dmg / 2);
    this.run.hp -= dmg;
    this._lastHit = { type: b.type, boss: b.boss, behind, parried, unparried: !parried, flee: false };
    if (!parried) {
      if (dmg > 0) {
        this.audio.play('sfx/hurt');
        vibrate('hit');
      }
    }
    if (this.run.hp <= 0) { this._die(); return; }
    if (b.drill) { // 教学战（§5 D8）：格挡成/败都继续 → 攻击教学
      const ids = [parried ? 'voice/tut_parry_ok' : 'voice/tut_parry_miss', 'voice/tut_attack'];
      this._speakGuarded(ids, () => this._playerTurn(), 12000);
      return;
    }
    this._dangerCheck();
    const drank = this._autoPotion();
    const ids = [];
    if (parried) ids.push('voice/btl_parried'); // 格挡成功（减伤 80%，§9.3 B 组 trigger）
    if (behind) ids.push('voice/btl_behind'); // 背后挨刀归因真话（§7.2）
    if (drank) ids.push('voice/st_hp_' + this._hpBand(this.run.hp, this._maxHp()));
    if (ids.length) this._speakGuarded(ids, () => this._playerTurn(), 8000);
    else this._playerTurn();
  }

  _dangerCheck() { // danger 签名：每层首次 ≤25% + Boss 半血（§10.1）
    if (!this._dangerFloorDone && this._hpBand(this.run.hp, this._maxHp()) === 4) {
      this._dangerFloorDone = true;
      this.guide.state('danger');
      vibrate('warning');
    }
  }

  _autoPotion() { // HP≤25% 且腰带有力 → 自动喝（§7.2）
    if (this.run.hp > 0 && this._hpBand(this.run.hp, this._maxHp()) === 4 && this.run.potion > 0) {
      this.run.potion = 0;
      this.run.hp = Math.min(this._maxHp(), this.run.hp + Math.ceil(this._maxHp() * 0.4));
      this.audio.play('sfx/potion');
      vibrate('pickup');
      return true;
    }
    return false;
  }

  _victory() {
    const b = this._battle;
    this.audio.play('sfx/enemy_die');
    vibrate('success');
    this.run.killsRun++;
    this.meta.kills++;
    const atkBefore = this.run.atkLv;
    if (this.run.killsRun % 4 === 0 && this.run.atkLv < 4) this.run.atkLv++;
    const justLeveled = this.run.atkLv > atkBefore;
    this.meta.gold += b.spec.gold; // 金币实时入元进度
    this.run.gold += b.spec.gold;
    if (b.spec.gold > 0) this.audio.play('sfx/coin');
    if (b.boss) this.run.cleared.push(this.run.floor);
    this._progress();
    this._save();
    if (b.type === 'king') { this._settleWin(); return; } // 终 Boss = 通关
    const lootBand = b.spec.gold < 6 ? 1 : b.spec.gold < 20 ? 2 : 3;
    const ids = b.drill ? ['voice/tut_kill', 'voice/btl_loot_' + lootBand] : ['voice/btl_kill', 'voice/btl_loot_' + lootBand];
    if (justLeveled) ids.push('voice/btl_lvup');
    this._speakGuarded(ids, () => {
      this._battle = null;
      if (this._drill && this._drill.step === 8) {
        // R2 D1-4：教学战胜利回教学也必须切回探索曲（R1 转写 t=35.8 起战斗鼓点
        // 泡全程的根因之一——bgm/explore 此前只在菜单关闭路径恢复）
        this.state = 'DRILL';
        this.audio.play('bgm/explore', { fadeMs: 400 });
        this._drillAdvance(9);
        return;
      }
      if (this._drill) { // D9 途中遇怪等：战后回教学态继续（否则状态卡在探索、drillDone 丢失）
        this.state = 'DRILL';
        this.audio.play('bgm/explore', { fadeMs: 400 });
        this._drillWatchdog(this._drill.step);
        return;
      }
      this._resumeExplore();
    }, 12000);
  }

  // ================================ 死亡 / 通关结算（§11/§12.7） ================================

  _buyUnlocks() {
    const bought = [];
    for (const l of LEGACIES) {
      if (this.meta.unlocks.includes(l.id)) continue;
      if (this.meta.gold >= l.price) {
        this.meta.gold -= l.price;
        this.meta.unlocks.push(l.id);
        bought.push(l.id);
      } else break; // 按价格升序，买不起即止
    }
    return bought;
  }

  _die() {
    const info = this._lastHit || { type: '?', boss: false, behind: false, unparried: true, parried: false };
    // 归因真话律（§11/§12 失败即不通过项）：句必须与真实死因对应
    const cause = info.behind ? 3 : (info.boss && info.unparried ? 2 : 1);
    const adv = info.behind ? 3 : (this.run.parries === 0 ? 1 : (this.run.flees === 0 ? 2 : 1));
    this._deathInfo = { cause, adv, lastHit: { ...info }, parries: this.run.parries, flees: this.run.flees };
    this._battle = null;
    this._stopWalk();
    this.state = 'SETTLE';
    this._session++;
    this._clearTimers();
    this.audio.setRateBoostEnabled(true); // E3：结算恢复
    this.audio.play('bgm/menu', { volume: 0.5 });
    this.guide.state('settle');
    vibrate('hit');
    this.meta.bestFloor = Math.max(this.meta.bestFloor, this.run.floor);
    this.meta.runs++;
    const newUnlocks = this._buyUnlocks();
    this.meta.pending.push(...newUnlocks); // 下一局开场播报（§7.4）
    const floorN = this.run.floor;
    // R2 D1-5：金币档与 TITLE 同一分档函数、同一本账（meta.gold，遗产购置后）。
    // R1 live：SETTLE 用 run 金币自设阈值报 meta_gold_3，TITLE 用 _goldBand(meta.gold)
    // 报 meta_gold_2——同一句 id 两套口径，「这趟」的账对不上。
    const goldBand = this._goldBand(this.meta.gold);
    this.run = null; // 死亡清 run 不清 meta
    this._save();
    this._settleChain = ['voice/die_intro', 'voice/die_cause_' + cause, 'voice/die_adv_' + adv,
      'voice/st_floor_' + floorN, 'voice/meta_gold_' + goldBand, 'voice/settle_stronger', 'voice/settle_again'];
    this._speakGuarded(this._settleChain, () => {}, 30000);
  }

  _settleWin() {
    this._battle = null;
    this._stopWalk();
    this.state = 'SETTLE';
    this._session++;
    this._clearTimers();
    this.audio.setRateBoostEnabled(true);
    this.audio.play('bgm/menu', { volume: 0.5 });
    this.guide.state('settle');
    vibrate('success');
    this.meta.bestFloor = Math.max(this.meta.bestFloor, 7);
    this.meta.runs++;
    const bought = this._buyUnlocks();
    const goldBand = this._goldBand(this.meta.gold); // R2 D1-5：与 TITLE 同函数同账本
    const ids = ['voice/settle_win_1', 'voice/settle_win_2', 'voice/meta_gold_' + goldBand];
    if (bought.length) for (const u of bought) ids.push('voice/unlock_' + u);
    ids.push('voice/settle_again');
    this.run = null;
    this._save();
    this._settleChain = ids; // SETTLE 双击=重听结算链（§2.3）
    this._speakGuarded(ids, () => {}, 30000);
  }

  _onSettleGesture(g) {
    if (g === 'tap') {
      this._enterTitle();
    } else if (g === 'doubletap') {
      this._speak(this._settleChain && this._settleChain.length
        ? this._settleChain : ['voice/settle_again']); // 重听结算链（重听入口）
    } else if (g === 'up') {
      this._speak(this._titleUpChain()); // 重听元进度段
    } else if (g === 'down') {
      this._openMenu();
    } else {
      this.guide.error({ voice: 'gd_invalid', onceKey: 'dungeon_invalid' });
    }
  }

  // ================================ 下潜（§4.2 DESCEND） ================================

  _descend(fromDrill) {
    this.state = 'DESCEND';
    this._session++;
    this._clearTimers();
    this._stopWalk();
    this.audio.play('sfx/stairs_down');
    this._speakGuarded(['voice/evt_descend'], () => {
      const next = this.run.floor + 1;
      this._enterFloor(next);
      if (fromDrill) {
        this.meta.drillDone = true;
        this._drill = null;
      }
      this._save();
      const ids = fromDrill ? ['voice/tut_done', 'voice/st_floor_' + next] : ['voice/st_floor_' + next];
      this._speakGuarded(ids, () => this._resumeExplore(), 8000);
    }, 8000);
  }

  // ================================ 演练教学 DRILL（§5） ================================

  _enterDrill() {
    this.state = 'DRILL';
    this._session++;
    this._clearTimers();
    this.audio.play('bgm/explore');
    this.audio.setRateBoostEnabled(false); // E3 豁免（教学=对局）
    this.guide.state('explore');
    this._drill = {
      step: -1, fails: 0, upDone: false, menuDone: false, turnedL: false, turnedR: false,
      bat: null, stairsSpoken: false,
    };
    this._drillEnter(0);
  }

  _drillWatchdog(step) {
    this.guide.watchdog({
      arm: true, at: [8000], say: [null], // 教学句不重播：纯 nudge（§10.2）
      cond: () => this.state === 'DRILL' && this._drill?.step === step,
    });
  }

  _drillEnter(step) {
    const d = this._drill;
    d.step = step;
    d.fails = 0;
    if (step === 0) {
      this._speakGuarded(['voice/intro_1', 'voice/intro_2', 'voice/tut_d0'], () => this._drillWatchdog(0), 20000);
    } else if (step === 1) {
      // D1 首次脉冲等待：旁白表为「—」，仍挂教学看门狗（§10.2 每步等待 [8s] 纯 nudge）
      this._drillWatchdog(1);
    } else if (step === 2) {
      this._speakGuarded(['voice/tut_front_rule'], () => this._drillWatchdog(2), 8000);
    } else if (step === 3) {
      this._speakGuarded(['voice/tut_side_rule'], () => this._drillWatchdog(3), 8000);
    } else if (step === 4) {
      // 自动面向东侧走道（走道 2 格 + 撞边界），保证"按住走 ≥2 格"可达成
      while (this.run.face !== 'E') this._turn(1);
      this._speakGuarded(['voice/tut_walk'], () => this._drillWatchdog(4), 8000);
    } else if (step === 5) {
      this._speakGuarded(['voice/tut_turn'], () => this._drillWatchdog(5), 8000);
    } else if (step === 6) {
      this._speakGuarded(['voice/tut_replay'], () => this._drillWatchdog(6), 8000);
    } else if (step === 7) {
      this._speakGuarded(['voice/tut_status', 'voice/tut_menu'], () => this._drillWatchdog(7), 12000);
    } else if (step === 8) {
      this._drillEnter8();
    } else if (step === 9) {
      this._speakGuarded(['voice/tut_stairs'], () => this._drillWatchdog9(), 8000);
    }
  }

  /** D9 看门狗（R2 D1-2）：8s nudge、30s 升级播楼梯暗示（铁器回声提示）。
   *  R1 live：D9 是唯一要求自行寻路的步骤，静置 72s 零事件零兜底——它是
   *  教学链里唯一没有救援出口的一步。 */
  _drillWatchdog9() {
    this.guide.watchdog({
      arm: true, at: [8000, 30000], say: [null, 'stair_hint_a'],
      cond: () => this.state === 'DRILL' && this._drill?.step === 9,
    });
  }

  _drillEnter8() {
    const d = this._drill;
    const bat = this._floor.mobs.find((m) => m.drill) || this._floor.mobs.find((m) => m.type === 'bat');
    if (!bat) { this._drillAdvance(9); return; } // 边界：门怪已亡（乱走触发过）→ 自动过
    d.bat = bat;
    while (this.run.face !== this._dominantDirTo(bat.x, bat.y)) this._turn(1); // 遭遇自动面对语义
    this._speakGuarded(['voice/tut_mob'], () => {
      this._drillWatchdog(8);
      this._drillApproach(); // 兜底：教学怪主动扑来，绝不等死
    }, 8000);
  }

  _dominantDirTo(tx, ty) {
    const dx = tx - this.run.pos.x, dy = ty - this.run.pos.y;
    if (Math.abs(dx) >= Math.abs(dy)) return dx >= 0 ? 'E' : 'W';
    return dy >= 0 ? 'S' : 'N';
  }

  _stepTowards(m, target) {
    const S = this._floor.size;
    const cand = [];
    for (const dd of Object.values(DIR_VEC)) {
      const nx = m.x + dd.dx, ny = m.y + dd.dy;
      if (nx < 0 || ny < 0 || nx >= S || ny >= S || this._floor.grid[ny][nx] !== 1) continue;
      cand.push({ x: nx, y: ny, d: Math.abs(nx - target.x) + Math.abs(ny - target.y) });
    }
    cand.sort((a, b) => a.d - b.d);
    return cand[0] || null;
  }

  _drillApproach() { // 教学怪每 1.2s 向玩家逼近一步，走进玩家格即触发战斗
    const s = this._session;
    this._after(1200, () => {
      if (s !== this._session) return;
      const d = this._drill;
      if (!d || d.step !== 8 || this.state !== 'DRILL' || this.menuOpen) return;
      const bat = d.bat;
      if (!bat || !this._floor.mobs.includes(bat)) return;
      const step = this._stepTowards(bat, this.run.pos);
      if (step) {
        if (step.x === this.run.pos.x && step.y === this.run.pos.y) { this._encounter(bat); return; }
        bat.x = step.x; bat.y = step.y;
        this._mobStepSound('bat', bat.x, bat.y);
      }
      this._drillApproach();
    });
  }

  _drillWrong() {
    const d = this._drill;
    if (!d) return;
    d.fails++;
    vibrate('error');
    if (d.fails >= 2) this._drillPass(); // 做错 ≤2 次后自动演示通过，不卡流程（§5）
  }

  _drillPass() {
    const d = this._drill;
    if (!d) return;
    d.fails = 0;
    this._drillAdvance(d.step + 1);
  }

  _drillAdvance(step) {
    if (step > 9) { this._drillDone(); return; }
    this._drillEnter(step);
  }

  _drillDone() { // 兜底：D9 未走楼梯而步数耗尽（极少见）——按跳过处理
    this.meta.drillDone = true;
    this._drill = null;
    this.guide.disarm(); // R2 D0-1：教学收尾注销全部教学再调度器（看门狗等）
    this._speakGuarded(['voice/tut_skip'], () => this._resumeExplore(), 8000);
  }

  _drillSkip() { // 下滑跳过教学（§5）：标志存进度，二周目不再进 DRILL
    this.meta.drillDone = true;
    this._drill = null;
    this._stopWalk();
    this._save();
    this.guide.disarm(); // R2 D0-1：同上，收尾即注销教学态挂件
    this._speakGuarded(['voice/tut_skip'], () => this._resumeExplore(), 8000);
  }

  _onDrillGesture(g) {
    const d = this._drill;
    if (!d) { this._onExploreGesture(g); return; }
    // D7 的下滑是"开菜单"教学动作本身；其余步骤下滑=跳过教学（§5）
    if (g === 'down' && d.step !== 7) { this._drillSkip(); return; }
    if (g === 'longpressend') return;
    switch (d.step) {
      case 0:
      case 2:
      case 3:
        if (g === 'tap') this._drillPass();
        else this._drillWrong();
        break;
      case 1: // 首次脉冲（FTUE 首输入点，≈t+15s）
        if (g === 'tap') {
          this._pulse();
          // 反馈句与下一步指令句串行（R2 D0-1：同 tick 双 play 会在引擎
          // _load 竞态下互相顶号——反馈句并入推进链，播完或 8s 兜底再进下一步）
          this._speakGuarded(['voice/tut_echo_come'], () => this._drillPass(), 8000);
        } else this._drillWrong();
        break;
      case 4: // 长按走（_walkStep 钩子里判定通过）
        if (g !== 'longpress') this._drillWrong();
        else this._startWalk();
        break;
      case 5: // 左滑+右滑各 1
        if (g === 'left') { d.turnedL = true; this._turn(-1); }
        else if (g === 'right') { d.turnedR = true; this._turn(1); }
        else { this._drillWrong(); break; }
        if (d.turnedL && d.turnedR) this._drillPass();
        break;
      case 6: // 双击重发（免费）
        if (g === 'doubletap') {
          this._pulse();
          // 同 D1：反馈句并入推进链，绝不与下一步旁白同 tick 双 play（D0-1）
          this._speakGuarded(['voice/tut_echo_come'], () => this._drillPass(), 8000);
        } else this._drillWrong();
        break;
      case 7: // 上滑状态 + 下滑开菜单再关（下滑已被跳过占用，关菜单用菜单内下滑）
        if (g === 'up') { d.upDone = true; this._speakStatus(); }
        else if (g === 'down') { this._openMenu(); break; }
        else { this._drillWrong(); break; }
        if (d.upDone && d.menuDone) this._drillPass();
        break;
      case 8: // 走向教学怪触发战斗（战斗内流程见 _encounter/_victory）
        if (g === 'longpress') this._startWalk();
        else if (g === 'tap') this._pulse();
        else if (g === 'up') this._speakStatus(); // 状态键 D7 已教：教学后可用（§4.3）
        else this._drillWrong();
        break;
      case 9: // 脉冲听铁器回声 → 自行走到楼梯 → 踏上后单击下潜
        if (g === 'tap') {
          if (this._onStairs && this._stairsSpokenFloor === this.run.floor) this._descend(true);
          else this._pulse();
        } else if (g === 'doubletap') this._pulse();
        else if (g === 'left') this._turn(-1);
        else if (g === 'right') this._turn(1);
        else if (g === 'up') this._speakStatus();
        else if (g === 'longpress') this._startWalk();
        // R2 D1-2：D9 每次操作后重挂看门狗（onGesture 的 disarm 会清掉它，
        // 而 D9 的脉冲/转身/走位不推进步骤——不重挂等于看门狗只在静置时活 8s）
        if (this.state === 'DRILL' && this._drill?.step === 9) this._drillWatchdog9();
        break;
      default:
        break;
    }
  }

  // ================================ 模态菜单（§2.4/§5.2 全球约定） ================================

  _openMenu() {
    if (this.menuOpen) return;
    this.menuFrom = this.state;
    this.menuOpen = true;
    this._menuItems = (this.state === 'TITLE' || this.state === 'SETTLE') ? TITLE_MENU : MENU_ITEMS;
    this._menuIdx = 0;
    this._session++;
    this._clearTimers();
    this._stopWalk();
    this._menuPause = null;
    if (this.menuFrom === 'BATTLE' && this._battle?.state === 'telegraph') {
      this._menuPause = { remain: Math.max(0, this._battle.windowEnd - performance.now()) };
    }
    this.audio.setRateBoostEnabled(true); // E3：菜单恢复快进
    this.audio.play('bgm/menu');
    this.guide.state('menu');
    this._speak(['voice/sys_menu', 'voice/' + this._menuItems[0]]);
  }

  _closeMenu() {
    this.menuOpen = false;
    const from = this.menuFrom;
    this.menuFrom = null;
    // R2 D1-1：关闭回执。R1 live 证据——打开有 menu 签名+sys_menu，关闭零反馈，
    // 盲手玩家只能靠下滑在开/关之间盲赌（「3 次下滑关不掉」实为关了又被下次
    // 下滑重开）。关闭补状态签名 earcon：回到哪个状态就报哪个签名。
    this.guide.state(from === 'BATTLE' ? 'battle'
      : from === 'SETTLE' ? 'settle'
        : (from === 'TITLE' ? 'menu' : 'explore'));
    if (from === 'BATTLE' && this._battle) {
      this.state = 'BATTLE';
      this.audio.play(this._battle.boss ? 'bgm/boss' : 'bgm/battle', { fadeMs: 400 });
      this.audio.setRateBoostEnabled(false);
      if (this._menuPause != null) { // 前摇暂停续播（剩余窗口）
        const b = this._battle;
        const remain = this._menuPause.remain;
        this._menuPause = null;
        b.windowEnd = performance.now() + remain;
        const s = this._session;
        this._after(remain, () => {
          if (s === this._session && this._battle === b && b.state === 'telegraph') this._enemyResolve();
        });
      } else {
        this._playerTurn();
      }
      return;
    }
    if (from === 'DRILL' && this._drill) {
      this.state = 'DRILL';
      this.audio.play('bgm/explore');
      this.audio.setRateBoostEnabled(false);
      const d = this._drill;
      if (d.step === 7) {
        d.menuDone = true;
        if (d.upDone) this._drillPass();
      }
      if (d.step === 8) this._drillApproach(); // 菜单期间逼近暂停过 → 恢复重挂
      return;
    }
    this.state = from || 'EXPLORE';
    if (from === 'EXPLORE') {
      this.audio.play('bgm/explore');
      this.audio.setRateBoostEnabled(false);
      this._startMobs();
      this._stuck.lastAct = performance.now();
      this._lastAmbAt = performance.now();
      this._stuckArm();
    } else {
      this.audio.play('bgm/menu'); // TITLE / SETTLE
    }
  }

  _onMenuGesture(g) {
    const items = this._menuItems;
    if (g === 'tap' || g === 'right') {
      this._menuIdx = (this._menuIdx + 1) % items.length; // 单击循环切项（每切播项名）
      this.audio.play('voice/' + items[this._menuIdx]);
    } else if (g === 'left') {
      this._menuIdx = (this._menuIdx + items.length - 1) % items.length;
      this.audio.play('voice/' + items[this._menuIdx]);
    } else if (g === 'doubletap') {
      this._menuExec(items[this._menuIdx]);
    } else if (g === 'up') {
      this._speak(['voice/help_explore', 'voice/help_battle', 'voice/settings_hint']);
    } else if (g === 'down') {
      this._closeMenu(); // 下滑=关闭
    }
  }

  _menuExec(item) {
    if (item === 'sys_menu_resume') {
      this._closeMenu();
    } else if (item === 'sys_menu_save') {
      this._save();
      this._speakGuarded(['voice/sys_saved'], () => this._goHome(), 4000);
    } else if (item === 'sys_menu_help') {
      this._speak(['voice/help_explore', 'voice/help_battle', 'voice/settings_hint']);
    } else if (item === 'sys_menu_restart') {
      const seed = this.run ? this.run.seed : null;
      this.menuOpen = false;
      this.menuFrom = null;
      if (seed != null) this._restartRun(seed);
      else this._closeMenu();
    }
  }

  // ================================ 卡关三级提示（§10.3） ================================

  _progress() { // 进展事件：拾取/战斗胜利/踏上楼梯格/击败窟主/下潜 → 重置分级
    this._stuck.shown.clear();
    this._stuck.nav = false;
    this._navLastDir = null;
    this._stuck.lastAct = performance.now();
  }

  _stuckArm() {
    if (this._stuckArmed) return;
    this._stuckArmed = true;
    const s = this._session;
    const loop = () => {
      if (s !== this._session) { this._stuckArmed = false; return; }
      if (this.state === 'EXPLORE' && !this.menuOpen) {
        this._stuckCheck();
        this._ambBreath();
      }
      this._after(5000, loop);
    };
    this._after(5000, loop);
  }

  /** 探索呼吸层（R2 D0-3②）：静默超 20s（无手势、无人声）播一段洞穴环境垫，
   *  消灭 R1 转写「教学后 350s 零人声零事件」的真空体感。游戏级定时器，
   *  guide=off 契约不受影响（off 只静向导层；环境垫是内容层）。 */
  _ambBreath() {
    const now = performance.now();
    if (now - this._lastAmbAt < AMB_AFTER_MS) return;
    if (now - this._stuck.lastAct < AMB_AFTER_MS) return; // 玩家仍在操作 = 不算静默
    if (this.audio.isVoicePlaying()) return; // 有人声就不垫
    this._lastAmbAt = now;
    this.audio.play('sfx/amb_cave', { volume: AMB_VOLUME });
  }

  _stuckCheck() {
    this._stuckFlush();
    const now = performance.now();
    const idle = now - this._stuck.lastAct;
    if (this._stuck.nav) {
      if (now - this._stuck.lastFire >= NAV_REPEAT_MS) this._stuckFire(3);
      return;
    }
    if (this._stuck.pending.length) return; // 待播中：等声道空出，不重复入队
    if (idle >= STUCK_LEVELS[2] && !this._stuck.shown.has('L3')) this._stuckFire(3);
    else if (idle >= STUCK_LEVELS[1] && !this._stuck.shown.has('L2')) this._stuckFire(2);
    else if (idle >= STUCK_LEVELS[0] && !this._stuck.shown.has('L1')) this._stuckFire(1);
  }

  _stuckStairDir() { // 楼梯（终局层=王座）绝对方位（与上滑面朝句同坐标系，自洽）
    const st = this._floor.stairs || this._floor.throne;
    if (!st) return 'e';
    const dx = st.x - this.run.pos.x, dy = st.y - this.run.pos.y;
    if (Math.abs(dx) >= Math.abs(dy)) return dx >= 0 ? 'e' : 'w';
    return dy >= 0 ? 's' : 'n';
  }

  _stuckFire(level) {
    this._stuck.lastFire = performance.now();
    vibrate('warning');
    let ids = [];
    if (level === 1) {
      const spec = FLOOR_SPECS[this.run.floor];
      const bossAlive = (spec.boss && !this.run.cleared.includes(this.run.floor)) || !!spec.final;
      // 终局层无楼梯（目标是王座上的窟中之王）→ 用「大东西守着」句，不说铁器
      ids = [bossAlive ? 'voice/stair_hint_b' : 'voice/stair_hint_a'];
    } else if (level === 2) {
      ids = ['voice/stair_dir_' + this._stuckStairDir()];
    } else {
      // 终局层目标是王座（stairs 为 null 时回退 throne，与 L2 明示同口径）
      const st = this._floor.stairs || this._floor.throne;
      if (st && st.x === this.run.pos.x && st.y === this.run.pos.y) {
        ids = ['voice/nav_done'];
      } else {
        ids = this._navRouteVoices();
      }
    }
    if (this.audio.isVoicePlaying()) {
      this._stuck.pending.push({ level, ids }); // 语音在播 → 入待播队列（escape round2 礼仪）
      // 未播级别不计入 shown：玩家操作作废后，下段静默期可重新触发（§10.3）
    } else {
      this._stuckSpoken(level, ids);
    }
  }

  _stuckSpoken(level, ids) { // 真正播出才算"已提示"（入队被作废的不算，§10.3）
    if (!ids.length) return;
    if (level === 3) {
      if (ids[0] === 'voice/nav_done') { this._progress(); return; }
      this._stuck.nav = true; // L3 带路：进入导航模式，每步播方向，抵达播 nav_done
    } else {
      this._stuck.shown.add('L' + level);
    }
    this._speak(ids);
  }

  /**
   * 带路第一步方向（R2 D1-3 导航目标格校验）：沿最短路（从目标反向 BFS）的
   * 第一步给方向，不再按直线差值指墙（R1 live：nav_n 咬定北边而北边实测撞墙）。
   * @returns {'N'|'E'|'S'|'W'|null} null = 不可达/已抵达
   */
  _navFirstStepDir(target) {
    if (!target) return null;
    if (target.x === this.run.pos.x && target.y === this.run.pos.y) return null;
    const dist = this._bfs(this._floor.grid, target);
    const d0 = dist[this.run.pos.y][this.run.pos.x];
    if (d0 < 0) return null;
    const S = this._floor.size;
    for (const [dir, dv] of Object.entries(DIR_VEC)) {
      const nx = this.run.pos.x + dv.dx, ny = this.run.pos.y + dv.dy;
      if (nx < 0 || ny < 0 || nx >= S || ny >= S || this._floor.grid[ny][nx] !== 1) continue;
      if (dist[ny][nx] === d0 - 1) return dir;
    }
    return null;
  }

  _navRouteVoices() { // L3 触发时的带路（R2：只报最短路第一步，后续每步校正）
    const st = this._floor.stairs || this._floor.throne;
    const dir = this._navFirstStepDir(st);
    if (!dir) return [];
    this._navLastDir = dir; // 首报计入节流：步行第一步同向不再重复
    this._navLastAt = performance.now();
    return ['voice/nav_' + DIR_KEY[dir]];
  }

  _navSpeakStep() { // 导航模式：按最短路逐步校正方向；抵达播 nav_done（终局层指向王座）
    const st = this._floor.stairs || this._floor.throne;
    if (!st) return;
    if (st.x === this.run.pos.x && st.y === this.run.pos.y) {
      this._speak(['voice/nav_done']);
      this._progress();
      return;
    }
    const dir = this._navFirstStepDir(st);
    if (!dir) return;
    const now = performance.now();
    // R2：同向短窗不重复（导航句既是反馈也是保险丝计数——500ms/步连报同向
    // 会撞引擎风暴熔断，且对玩家是噪声；改向立即播，同向 ≥1.5s 提醒一次）
    if (dir === this._navLastDir && now - this._navLastAt < NAV_MIN_GAP_MS) return;
    this._navLastDir = dir;
    this._navLastAt = now;
    this._speak(['voice/nav_' + DIR_KEY[dir]]);
  }

  _stuckFlush() {
    if (!this._stuck.pending.length) return;
    if (this.audio.isVoicePlaying()) return;
    const { level, ids } = this._stuck.pending.shift();
    this._stuckSpoken(level, ids);
  }

  _stuckDiscardPending() { // 玩家操作即作废未播级别（§10.3）
    this._stuck.pending.length = 0;
  }

  // ================================ 向导看门狗（§10.2） ================================

  _armExploreWatchdog() {
    this.guide.watchdog({
      arm: true, at: [10000, 25000], say: ['gd_pulse', null],
      cond: () => this.state === 'EXPLORE' && !this.menuOpen,
    });
  }

  // ================================ 语音链 / 计时器基础设施 ================================

  _speak(ids, onDone) { // 串行链：自然播完才接下一句；被顶掉/打断则整条作废
    if (!ids.length) { if (onDone) onDone(); return; }
    const s = this._session;
    const [head, ...rest] = ids;
    this.audio.play(head, {
      onComplete: () => {
        if (s !== this._session) return;
        this._speak(rest, onDone);
      },
    });
  }

  _speakGuarded(ids, onDone, guardMs = 10000) { // 播完或超时先到先触发，流程绝不卡死
    const s = this._session;
    let fired = false;
    const fire = () => {
      if (fired || s !== this._session) return;
      fired = true;
      if (onDone) onDone();
    };
    this._speak(ids, fire);
    this._after(guardMs, fire);
  }

  _after(ms, fn) {
    const s = this._session;
    const id = setTimeout(() => {
      this._timers = this._timers.filter((t) => t !== id);
      if (s === this._session) fn();
    }, ms);
    this._timers.push(id);
    return id;
  }

  _clearTimers() {
    for (const id of this._timers) clearTimeout(id);
    this._timers = [];
    this._stuckArmed = false;
  }

  // ================================ 存档（§11） ================================

  _summary() {
    const n = this.meta.unlocks.length;
    if (!this.run) return `深处归来 · 金币${this.meta.gold} · 遗产${n}/5`;
    const band = this._hpBand(this.run.hp, this._maxHp());
    return `第${this.run.floor}层 · ${HP_BAND_TEXT[band]} · 金币${this.meta.gold} · 遗产${n}/5`;
  }

  _save() {
    const r = this.run;
    const data = {
      schema: 1,
      game: 'dungeon',
      updatedAt: new Date().toISOString(),
      summary: this._summary(),
      meta: {
        gold: this.meta.gold, unlocks: [...this.meta.unlocks], bestFloor: this.meta.bestFloor,
        runs: this.meta.runs, kills: this.meta.kills, drillDone: this.meta.drillDone,
        pending: [...this.meta.pending],
      },
      run: r ? {
        seed: r.seed, floor: r.floor, pos: [r.pos.x, r.pos.y], face: r.face,
        hp: r.hp, atkLv: r.atkLv, weapon: r.weapon, armor: r.armor, potion: r.potion,
        veilUsedFloor: r.veilUsedFloor, killsRun: r.killsRun, looted: [...r.looted],
        cleared: [...r.cleared], parries: r.parries, flees: r.flees, gold: r.gold,
      } : null,
    };
    try { localStorage.setItem(SAVE_KEY, JSON.stringify(data)); } catch (_) { /* 隐私模式 */ }
    try {
      const auth = JSON.parse(localStorage.getItem(AUTH_KEY));
      if (!auth || !auth.token) return;
      fetch('/api/progress', {
        method: 'PUT',
        headers: { 'Content-Type': 'application/json', 'Authorization': 'Bearer ' + auth.token },
        body: JSON.stringify({ game: 'dungeon', data }),
      }).catch(() => { /* 离线静默 */ });
    } catch (_) { /* 静默 */ }
  }

  _loadSave() {
    try {
      const data = JSON.parse(localStorage.getItem(SAVE_KEY));
      if (!data || data.schema !== 1 || !data.meta) return null;
      return data;
    } catch (_) {
      return null;
    }
  }
}