// server/sim/simdata.js — data access + normalisation layer for the simulation.
//
// The sim never reads raw JSON records directly: every chess / enemy / token record is normalised once into an
// engine "def" (cached, frozen input is never mutated). Sources, in order:
//   1. an injected data object (Battle opts.data: `{ chess, enemies, tokens, stages, waves }` maps or getters)
//   2. the default source:
//        Node    — `server/data.js → getData()` (data/*.json generated by tools/build-data.mjs) with a research JSON
//                  fallback (docs/research/03-operators.json, 05-enemies.json, 05-maps.json), loaded by ./nodeData.js
//                  so the sim and its tests work before/without generated data;
//        browser — whatever the page injected with `setSimData(data)` (the fetched /data/*.json, DESIGN §14).
// Both the research record shapes and the build-data shapes (docs/DATA.md) are accepted.
//
// Operator loadouts (DESIGN §16, DATA.md §2.2): `getChess(id, { skillIndex, moduleId })` resolves the def of a chess
// with the selected skill (def.skill / its blackboard / trigger) and — elite only — module (stats = statsBase + attr,
// trait, talents); `getToken(id, owner, ownerLoadout)` the owner-loadout variant of a summon. Pure helpers for the
// match / UI (implemented in shared/loadoutRecord.js, re-exported here): resolveLoadout, loadoutRecord (the resolved
// chess record), composeStats / composeTalents. (Which choices a player may make is shared/protocol.js
// loadoutOptions / checkLoadout.)
// 补位 stand-ins (DATA.md §18): `getChess(id, { standIn: true })` = the def of a NORMAL chess fielded as its official
// stand-in (shared/standIn.js standInRecord over data/backups.json: the chess's ids, bonds, 特质, tier; the stand-in's
// body, skill `backup.skillIndex` and module `backup.uniEquipId` — any other skill / module choice is ignored), with
// `def.standInFor` = the replaced operator's charId and `def.charId` = the stand-in's (content/index.js looks its kit
// up by that charId). A PRESET / DIY chess, or a source without backups.json, gives the chess's own def instead.
// 自选 picks (DATA.md §18): `getChess(slotId, { diy: { charId, skillIndex, uniEquipId } })` = the def of a DIY slot (its
// `_a` / `_b` id) filled with that operator (shared/diy.js diyRecordOf: the slot's tier / price / status, no 特质, the
// pick's derived bonds, the operator's body, skill and module — a prototype's locked ones), with `def.diyFor` = the
// slot's base id, `def.charId` = the operator (its kit, content/index.js kitOf), `def.loadout.diy` = the checked pick and
// `def.tokenOwner` = the key of its summons' variants (data/backups.json `tokens`, read by getToken); null for an illegal
// pick.
// Potential (潜能 1–6, 0.2.2 — the player's 干员调配 setting; shared/potential.js): a loadout's `potential` composes the
// chess / 自选 record at it (`def.loadout.potential`; full potential 6 is the default and the data's own) and the
// summons' variants at their owner's potential (getToken / getDiyToken: talents, a 自选 summon's deploy limit / count).
// A 补位 stand-in and a prototype 自选 pick have no potential.
//
// This module is pure ESM shared with browsers (served at /sim/): no Node API is imported here. Under Node the default
// loader (./nodeData.js) is imported dynamically at module evaluation; browsers never load it.
//   setSimData(data)  inject the full game data object ({ chess, enemies, tokens, stages, waves, bonds, items, … });
//                     it becomes the default source (no research fallback) and `getSimData()` (the browser stand-in of
//                     server/data.js getData() used by sim/content/support serves it).
//   getSimData()      the injected data (browser) or the generated data (Node), or null.

import { resolveRecordLoadout, composeStats, composeTalents, loadoutRecord } from '../../shared/loadoutRecord.js';
import { atPotential, isPotential, POTENTIAL_DEFAULT, cultivateMul } from '../../shared/potential.js';
import { standInRecord } from '../../shared/standIn.js';
import { diyRecordOf, diyTokenOwner } from '../../shared/diy.js';
import { normHitArea } from './body.js';

// ---------------------------------------------------------------------------------------------------------------
// generic helpers

/** Flatten an Arknights blackboard `[{key,value,valueStr}]` (or a plain object) into `{ key: value }`. */
export function flattenBlackboard(bb) {
  if (!bb) return {};
  if (!Array.isArray(bb)) return { ...bb };
  const out = {};
  for (const e of bb) {
    if (!e || e.key == null) continue;
    const v = e.valueStr != null && e.valueStr !== '' && (e.value === 0 || e.value == null) ? e.valueStr : e.value;
    out[e.key] = v;
  }
  return out;
}

const num = (v, d = 0) => (typeof v === 'number' && Number.isFinite(v) ? v : (typeof v === 'string' && v.trim() !== '' && Number.isFinite(+v) ? +v : d));

/**
 * Is an items.json record a shop item — what the 调度中心 item slot, the 道具补给 / 机密商店 cards and the "random
 * item" pools (pool_equip_normal …) draw from: a normal EQUIP item with a tier, neither hidden by the official shop
 * table (`hideInShop`: the Arts) nor one of the effect-only items build-data marks `shopExcluded` (the special
 * 维式重锤 of 维多利亚 / 洛洛, 突变细胞 — tools/build-data.mjs SHOP_EXCLUDED_ITEMS).
 */
export function isShopItem(it) {
  return !!it && typeof it === 'object' && !it.isGolden && !it.hideInShop && !it.shopExcluded && it.itemType === 'EQUIP' && Number.isInteger(it.tier);
}

function toArrayOfPairs(grid) {
  if (!Array.isArray(grid)) return null;
  const out = [];
  for (const p of grid) {
    if (Array.isArray(p) && p.length >= 2) out.push([num(p[0]), num(p[1])]);
    else if (p && typeof p === 'object' && ('row' in p || 'r' in p)) out.push([num(p.row ?? p.r), num(p.col ?? p.c)]);
  }
  return out;
}

export function normDmgType(v, fallback = 'phys') {
  if (v == null) return fallback;
  const s = String(Array.isArray(v) ? v[0] : v).toUpperCase();
  if (s.startsWith('PHYS')) return 'phys';
  if (s.startsWith('MAG') || s === 'ARTS') return 'arts';
  if (s === 'HEAL' || s === 'HEALING') return 'heal';
  if (s === 'TRUE' || s === 'REAL' || s === 'PURE') return 'true';
  if (s === 'NO_DAMAGE' || s === 'NONE' || s === 'NO') return 'none';
  if (s.startsWith('ELEM')) return 'true';
  return fallback;
}

export function normSpType(v) {
  const s = String(v ?? '').toUpperCase();
  if (s.includes('TIME')) return 'time';
  if (s.includes('ATTACK')) return 'attack';
  if (s.includes('DAMAGE') || s.includes('HURT')) return 'hurt';
  return 'none';
}

export function normTriggerRule(v) {
  const s = String(v ?? 'DEFAULT').toUpperCase();
  if (s === 'ALWAYS' || s === 'SP_FULL') return 'SP_FULL';
  if (s.startsWith('CUSTOM_RANGE')) return 'CUSTOM_RANGE';
  return s;
}

// ---------------------------------------------------------------------------------------------------------------
// def normalisers

/** Normalise the skill part of a chess/token record. Returns null when there is no skill. */
export function normalizeSkill(rec) {
  const s = rec && (rec.skill ?? null);
  if (!s || typeof s !== 'object') return null;
  const bb = s.bb ? { ...s.bb } : flattenBlackboard(s.blackboard);
  const trig = s.trigger ?? rec.skillTrigger ?? {};
  let rule = normTriggerRule(typeof trig === 'string' ? trig : trig.rule);
  const matchedBy = typeof trig === 'object' ? String(trig.matchedBy ?? '') : '';
  const skillIndex = s.skillIndex ?? s.index ?? null;
  const skillType = String(s.skillType ?? s.type ?? 'MANUAL').toUpperCase();
  // Class rows (profession / subprofession, research-shaped records carry `matchedBy`) apply to every MANUAL skill of the
  // class and never to an AUTO one (PRTS 卫戍协议/帮助 技能策略; tools/build-data.mjs resolveTrigger does the same for data).
  if (/^(profession|subProfession)/.test(matchedBy) && skillType !== 'MANUAL') rule = 'DEFAULT';
  const trigGrid = toArrayOfPairs((typeof trig === 'object' && (trig.customRangeGrid ?? trig.rangeGrid ?? trig.grid)) || rec.skillTriggerCustomRangeGrid);
  if (/^skcom_withdraw/.test(String(s.skillId ?? s.id ?? ''))) return null;
  const durRaw = s.duration ?? bb.duration ?? 0;
  return {
    id: s.skillId ?? s.id ?? 'skill',
    name: s.name ?? '',
    index: skillIndex,
    skillType,
    durationType: String(s.durationType ?? 'NONE').toUpperCase(),
    duration: num(durRaw, 0),
    spType: normSpType(s.spType),
    spCost: Math.max(0, num(s.spCost, 0)),
    initSp: Math.max(0, num(s.initSp, 0)),
    maxCharges: Math.max(1, num(s.maxChargeTime ?? s.maxCharges ?? s.charges, 1)),
    rangeGrid: toArrayOfPairs(s.rangeGrid),
    // `allies` (data: an ally row, tools/build-data.mjs TRIGGER_ALLY_RULES — 黍 S3) — skills.js `trigger.allies`
    trigger: typeof trig === 'object' && trig.allies === true ? { rule, grid: trigGrid, allies: true } : { rule, grid: trigGrid },
    kind: s.kind ?? null,
    bb,
    description: s.description ?? s.desc ?? '',
  };
}

function normStats(st) {
  st = st || {};
  return {
    maxHp: Math.max(1, num(st.maxHp ?? st.hp, 1000)),
    atk: Math.max(0, num(st.atk, 0)),
    def: Math.max(0, num(st.def, 0)),
    res: Math.max(0, num(st.magicResistance ?? st.res ?? st.resistance, 0)),
    aspd: num(st.attackSpeed ?? st.aspd, 100) || 100,
    bat: Math.max(0.05, num(st.baseAttackTime ?? st.bat, 1)),
    blockCnt: Math.max(0, num(st.blockCnt ?? st.block, 1)),
    cost: Math.max(0, num(st.cost, 10)),
    respawnTime: Math.max(0, num(st.respawnTime ?? st.redeploy, 70)),
    spRecovery: num(st.spRecoveryPerSec ?? st.spRecovery, 1),
    tauntLevel: num(st.tauntLevel ?? st.taunt, 0),
    massLevel: num(st.massLevel ?? st.mass, 0),
    hpRecoveryPerSec: num(st.hpRecoveryPerSec, 0),
    moveSpeed: num(st.moveSpeed, 1),
  };
}

/** Normalise a chess record (research 03 shape or data/chess.json shape) into an OpDef. */
export function normalizeChess(rec) {
  const id = rec.chessId ?? rec.id;
  const golden = !!(rec.isGolden ?? rec.golden ?? /_b$/.test(String(id)));
  const baseId = rec.baseChessId ?? rec.baseId ?? String(id).replace(/_b$/, '_a');
  const skill = normalizeSkill(rec);
  const talents = (rec.talents ?? []).map((t) => ({
    name: t.name ?? '',
    description: t.description ?? t.desc ?? '',
    bb: t.bb ? { ...t.bb } : flattenBlackboard(t.blackboard),
    bbStr: t.bbStr ? { ...t.bbStr } : {},
    rangeGrid: toArrayOfPairs(t.rangeGrid),
    tokenKey: t.tokenKey ?? null,
  }));
  return {
    type: 'chess',
    id,
    baseId,
    golden,
    name: rec.name ?? id,
    charId: rec.charId ?? null,
    tier: num(rec.tier, 1),
    rarity: num(rec.rarity, 4),
    profession: String(rec.profession ?? 'WARRIOR').toUpperCase(),
    subProf: rec.subProfessionId ?? rec.subProfession ?? rec.subProf ?? null,
    position: String(rec.position ?? 'MELEE').toUpperCase(),
    bonds: [...(rec.bondIds ?? rec.bonds ?? [])],
    stats: normStats(rec.stats),
    rangeGrid: toArrayOfPairs(rec.rangeGrid ?? rec.range?.grid) ?? [[0, 0], [0, 1]],
    dmgType: rec.dmgType ? normDmgType(rec.dmgType) : null,
    attackKind: rec.attackKind ?? null,
    projectile: rec.projectile ?? null,
    canHitFly: rec.canHitFly ?? null,
    targetPriority: rec.targetPriority ?? null,
    splashRadius: rec.splashRadius ?? null,
    trait: typeof rec.trait === 'string' ? rec.trait : (rec.trait?.desc ?? rec.traitText ?? ''),
    traitBb: rec.traitBb ?? (rec.trait && typeof rec.trait === 'object' ? { ...(rec.trait.bb || {}) } : flattenBlackboard(rec.traitBlackboard)),
    immune: immuneSet(rec.immunities ?? rec.immune),
    skill,
    talents,
    tokens: rec.tokens ?? [],
    spine: rec.assets?.spine ?? rec.spine ?? rec.charId ?? null,
    avatar: rec.assets?.avatar ?? rec.avatar ?? rec.charId ?? null,
    // a 补位 stand-in (shared/standIn.js): the replaced operator's charId — `charId` is the stand-in's (absent otherwise)
    ...(rec.standInFor ? { standInFor: rec.standInFor } : null),
    // a 自选 piece (shared/diy.js): the slot's base id — `charId` is the operator's (absent otherwise)
    ...(rec.diyFor ? { diyFor: rec.diyFor } : null),
    raw: rec,
  };
}

// ---------------------------------------------------------------------------------------------------------------
// operator loadouts (DESIGN §16): selected skill + module of a chess
//
// A loadout `{ skillIndex, moduleId }` (also accepted: `{ skill, module }`, the client's per-browser shape) is resolved
// against a data/chess.json record: `skillIndex` must be the index of one of `rec.skills` (the skills unlocked at the
// record's status), `moduleId` 'none' or the uniEquipId of one of `rec.modules` (golden chess only). Anything else —
// missing, unknown, not unlocked at this record (a tier-1/2 normal chess has no S3) — falls back to the default.
// Research-shaped records (no `skills` list) always resolve to their single skill.

/** Resolve a loadout against a chess record (shared/loadoutRecord.js resolveRecordLoadout). */
export const resolveLoadout = resolveRecordLoadout;
export { composeStats, composeTalents, loadoutRecord };

/** Cache key suffix of a resolved non-default loadout ('' for the default). */
export function loadoutKey(lo) {
  return lo && !lo.isDefault ? `|s${lo.skillIndex}|m${lo.moduleId ?? ''}${lo.potentialIsDefault === false ? `|p${lo.potential}` : ''}` : '';
}

/** Build an immunity Set from an object `{stun:true,…}` or an array `['stun', 'feared']`. */
export function immuneSet(v, extra = null) {
  const out = new Set();
  const add = (k) => out.add(String(k).replace(/Immune$/, '').toLowerCase());
  if (Array.isArray(v)) v.forEach(add);
  else if (v && typeof v === 'object') for (const k of Object.keys(v)) if (v[k]) add(k);
  if (Array.isArray(extra)) extra.forEach(add);
  return out;
}

/** data/enemies.json `attackAnim` → { dur, hit } (hit null = none: half the clip), or null when malformed / absent. */
function normAttackAnim(a) {
  const dur = Number(a?.dur);
  if (!(Number.isFinite(dur) && dur > 0)) return null;
  const hit = Number(a.hit);
  return { dur, hit: a.hit != null && Number.isFinite(hit) ? Math.min(dur, Math.max(0, hit)) : null };
}

/** Normalise an enemy record (research 05 shape or data/enemies.json shape) into an EnemyDef. */
export function normalizeEnemy(key, e) {
  const st = e.stats ?? e;
  const range = num(st.rangeRadius ?? st.range, 0);
  const applyWay = String(e.applyWay ?? st.applyWay ?? (range > 0 ? 'RANGED' : 'MELEE')).toUpperCase();
  let dmgType = normDmgType(st.dmgType ?? e.dmgType ?? e.dmg, 'phys');
  if (applyWay === 'NONE') dmgType = 'none';
  const immune = immuneSet(st.immunities ?? e.immune ?? e.immunities, st.otherImmunities ?? e.otherImmunities);
  const extra = e.extra ?? {};
  return {
    type: 'enemy',
    id: key,
    key,
    name: e.name ?? key,
    rank: String(e.rank ?? 'NORMAL').toUpperCase(),
    maxHp: Math.max(1, num(st.maxHp ?? st.hp, 1000)),
    atk: Math.max(0, num(st.atk, 0)),
    def: Math.max(0, num(st.def, 0)),
    res: Math.max(0, num(st.res ?? st.magicResistance, 0)),
    aspd: num(st.aspd ?? st.attackSpeed, 100) || 100,
    bat: Math.max(0.1, num(st.bat ?? st.baseAttackTime, 2)),
    rangeRadius: range > 0 ? range : 0,
    moveSpeed: Math.max(0, num(st.moveSpeed ?? st.spd, 1)),
    massLevel: num(st.massLevel ?? st.mass, 1),
    lpr: num(st.lpr ?? e.lpr ?? e.lifePointReduce, 1),
    motion: String(st.motion ?? e.motion ?? 'WALK').toUpperCase() === 'FLY' ? 'FLY' : 'WALK',
    applyWay,
    dmgType,
    immune,
    tauntLevel: num(st.tauntLevel ?? extra.tauntLevel ?? e.tauntLevel, 0),
    blockCnt: Math.max(1, num(st.blockCnt ?? e.blockCnt ?? extra.blockCnt, 1)),
    epResistance: num(st.elementRes ?? extra.epResistance ?? e.epResistance, 0),
    epDamageResistance: num(st.elementDmgRes ?? extra.epDamageResistance ?? e.epDamageResistance, 0),
    hpRecoveryPerSec: num(st.hpRecoveryPerSec ?? extra.hpRecoveryPerSec ?? e.hpRecoveryPerSec, 0),
    notCountInTotal: !!(e.notCountInTotal),
    hitArea: normHitArea(e.hitArea),   // huge units only (body.js); null = a point
    staticBody: !!e.staticBody,        // 静态刚体: pushes / pulls never move it (Battle._displaceable)
    attackAnim: normAttackAnim(e.attackAnim),   // its attack clip { dur, hit } (ai.js attackStand); null = none known
    attackMoves: !!e.attackMoves,      // 「不停止移动」: never stops to attack (ai.js attackStand)
    tags: e.tags ?? [],
    abilities: e.abilities ?? [],
    skills: e.skills ?? [],
    talent: e.talents?.bb ?? e.talent ?? {},
    spine: e.spine ?? key,
    avatar: e.iconId ?? e.avatar ?? key,
    raw: e,
  };
}

/** Normalise a token record (+ optional owner-specific variant: `t.variants[ownerChessId]`). */
export function normalizeToken(id, t0, ownerChessId = null, variantOverride = null) {
  const variant = variantOverride ?? (ownerChessId && t0.variants ? t0.variants[ownerChessId] : null);
  const t = variant ? { ...t0, ...variant } : t0;
  const skill = normalizeSkill(t);
  const traitText = typeof t.trait === 'string' ? t.trait : (t.trait?.desc ?? '');
  const desc = String(t.description ?? t.desc ?? traitText ?? '');
  const stats = normStats(t.stats ?? {});
  const ak = t.attackKind ? String(t.attackKind).toLowerCase() : null;
  return {
    type: 'token',
    id,
    baseId: id,
    golden: false,
    name: t.name ?? id,
    charId: id,
    tier: num(t.tier, 1),
    rarity: 1,
    profession: String(t.profession ?? 'TOKEN').toUpperCase(),
    subProf: t.subProfessionId ?? t.subProf ?? null,
    position: String(t.position ?? 'MELEE').toUpperCase(),
    bonds: [],
    stats,
    rangeGrid: toArrayOfPairs(t.rangeGrid) ?? [[0, 0], [0, 1]],
    dmgType: t.dmgType ? normDmgType(t.dmgType) : (/法术/.test(desc) ? 'arts' : /真实/.test(desc) ? 'true' : /恢复|治疗/.test(desc) ? 'heal' : 'phys'),
    attackKind: ak,
    projectile: t.projectile ?? null,
    canHitFly: t.canHitFly ?? null,
    targetPriority: t.targetPriority ?? null,
    untargetable: t.untargetable ?? /不会受到攻击|不会成为/.test(desc),
    // abnormal effects held from the start (tokens.json `abnormal`, PRTS summon pages): 'healFree' 禁疗, 'isolated' 孤立
    abnormal: Array.isArray(t0.abnormal) ? t0.abnormal.filter((x) => typeof x === 'string') : [],
    immune: immuneSet(t.immunities),
    trait: desc,
    traitBb: t.trait && typeof t.trait === 'object' ? { ...(t.trait.bb || {}) } : {},
    skill,
    // chess/token records carry a talent array; enemy-shaped records (炎佑 enemy_9012_acloon) one `{ bb, bbStr }` object
    talents: (Array.isArray(t.talents) ? t.talents : t.talents && typeof t.talents === 'object' ? [t.talents] : [])
      .filter((x) => x && typeof x === 'object')
      .map((x) => ({ name: x.name ?? '', description: x.desc ?? x.description ?? '', bb: x.bb ? { ...x.bb } : flattenBlackboard(x.blackboard), bbStr: x.bbStr ? { ...x.bbStr } : {}, rangeGrid: toArrayOfPairs(x.rangeGrid), tokenKey: x.tokenKey ?? null })),
    tokens: [],
    count: num(t.count, 1),
    // how the owner (with its loadout) produces this token: ⊆ ['talent','skill','display'] (data variant / bySkill);
    // [] or ['display'] = the owner does not produce it; null = unknown (no owner variant)
    sources: variant && Array.isArray(t.sources) ? [...t.sources] : null,
    spine: t.spine ?? t.assets?.spine ?? id,
    avatar: t.avatar ?? t.assets?.avatar ?? id,
    raw: t0,
  };
}

// ---------------------------------------------------------------------------------------------------------------
// stage / route / wave helpers

/** Accepts a stage entry and returns a sim-ready stage `{ id, rows (bottom-first strings), legend, devices }`. */
export function normalizeStage(id, s) {
  if (!s) return null;
  if (s._norm) return s;
  let rows = s.rows ?? s.grid ?? null;
  if (!rows && Array.isArray(s.rowsTopDown)) rows = [...s.rowsTopDown].reverse().map((l) => String(l).replace(/^\s*\d+\s/, ''));
  const devices = (s.devices ?? []).map((d) => ({
    key: d.key ?? d.id,
    name: d.name ?? d.key,
    row: num(d.row ?? (Array.isArray(d.pos) ? d.pos[0] : d.pos?.row), -1),
    col: num(d.col ?? (Array.isArray(d.pos) ? d.pos[1] : d.pos?.col), -1),
    dir: d.dir ?? 'UP',
    hidden: !!d.hidden,
    active: d.active !== false,
    role: d.role ?? null,
    stats: d.stats ?? null,
    raw: d,
  }));
  return { _norm: true, id: s.id ?? s.stageId ?? id, name: s.name ?? id, rows, legend: s.legend ?? s.tiles ?? null, devices, special: s.special ?? null, raw: s };
}

function pairOf(v) {
  if (Array.isArray(v)) return [num(v[0]), num(v[1])];
  if (v && typeof v === 'object') return [num(v.row ?? v.r), num(v.col ?? v.c)];
  return null;
}

/** Normalise a route (research `{m,s,e,cp}` or data `{motion,start,end,checkpoints}`) into a RouteSpec. */
export function normalizeRoute(r) {
  if (!r) return null;
  const m = String(r.motion ?? r.m ?? 'W').toUpperCase();
  const motion = m.startsWith('F') ? 'FLY' : 'WALK';
  const start = pairOf(r.start ?? r.s ?? r.startPosition);
  const end = pairOf(r.end ?? r.e ?? r.endPosition);
  const cps = [];
  if (Array.isArray(r.steps) && r.steps.length) {
    for (const st of r.steps) {
      const t = String(st.t ?? st.type ?? 'move').toUpperCase();
      cps.push({ type: normCpType(t), pos: pairOf(st.p ?? st.pos) ?? [0, 0], time: num(st.s ?? st.time, 0) });
    }
    return { motion, start, end, checkpoints: cps };
  }
  for (const cp of r.checkpoints ?? r.cp ?? []) {
    if (Array.isArray(cp) && typeof cp[0] === 'number') {
      cps.push({ type: 'MOVE', pos: [num(cp[0]), num(cp[1])], time: 0 });
    } else if (Array.isArray(cp)) {
      const [type, a, b, t] = cp;
      cps.push({ type: normCpType(type), pos: [num(a), num(b)], time: num(t, 0) });
    } else if (cp && typeof cp === 'object') {
      cps.push({ type: normCpType(cp.type), pos: pairOf(cp.pos ?? cp.position ?? [cp.row, cp.col]) ?? [0, 0], time: num(cp.time ?? cp.t, 0) });
    }
  }
  return { motion, start, end, checkpoints: cps };
}

function normCpType(t) {
  const s = String(t ?? 'MOVE').toUpperCase();
  if (s.includes('DISAPPEAR')) return 'DISAPPEAR';
  if (s.includes('APPEAR')) return 'APPEAR';
  if (s.includes('WAIT')) return 'WAIT';
  return 'MOVE';
}

/**
 * Convert a wave template (research roundLevels entry or data/waves.json entry) into `{ routes, spawns }`.
 * Research actions: `{ key, n, pre, int, route }` inside waves[].fragments[].actions (times are cumulative:
 * wave.preDelay + fragment.preDelay + action.pre).
 */
export function spawnsFromTemplate(tpl, { mods = null, tag = undefined } = {}) {
  if (!tpl) return { routes: [], spawns: [] };
  const routes = (tpl.routes ?? []).map(normalizeRoute);
  const spawns = [];
  if (Array.isArray(tpl.spawns)) {
    for (const s of tpl.spawns) {
      if (s.action && String(s.action).toUpperCase() !== 'SPAWN') continue; // non-spawn actions are content's job
      const key = s.enemyKey ?? s.key;
      if (!key) continue;
      const sp = {
        time: num(s.time ?? s.t, 0), enemyKey: key, routeIndex: num(s.routeIndex ?? s.route, 0),
        count: Math.max(1, num(s.count ?? s.n, 1)), interval: num(s.interval ?? s.int, 0),
        mods: s.mods ?? mods ?? undefined, tag: s.tag ?? tag, bounty: s.bounty, sourcePlayerId: s.sourcePlayerId,
      };
      if (s.unharmful || sp.tag === 'part') sp.countInTotal = false;
      if (s.hidden) sp.hidden = true;
      if (s.group != null) sp.group = s.group;
      spawns.push(sp);
    }
  } else {
    let waveT = 0;
    for (const w of tpl.waves ?? []) {
      waveT += num(w.preDelay, 0);
      let fragT = waveT;
      let fragEnd = fragT;
      for (const f of w.fragments ?? []) {
        fragT += num(f.preDelay, 0);
        for (const a of f.actions ?? []) {
          const key = a.key ?? a.enemyKey;
          if (!key || !String(key).startsWith('enemy_')) continue;
          const n = Math.max(1, num(a.n ?? a.count, 1));
          const t0 = fragT + num(a.pre ?? a.preDelay, 0);
          const iv = num(a.int ?? a.interval, 0);
          spawns.push({ time: t0, enemyKey: key, routeIndex: num(a.route ?? a.routeIndex, 0), count: n, interval: iv, mods: mods ?? undefined, tag });
          fragEnd = Math.max(fragEnd, t0 + iv * (n - 1));
        }
      }
      waveT = Math.max(waveT, fragEnd) + num(w.postDelay, 0);
    }
  }
  return { routes, spawns, maxPlayTime: tpl.maxPlayTime ?? tpl.timeLimit ?? null, overrides: tpl.overrides ?? null, extraRoutes: (tpl.extraRoutes ?? []).map(normalizeRoute) };
}

// ---------------------------------------------------------------------------------------------------------------
// data sources

const IS_NODE = typeof process !== 'undefined' && !!(process && process.versions && process.versions.node);

/** Node default loader (./nodeData.js) or null in browsers. */
let nodeLoader = null;
/** Raw generated data (Node: data/*.json) or the data injected with setSimData (browser). */
let generatedCache = null;
/** Raw research maps (Node only; loaded lazily). */
let researchCache = null;
let injected = false;

if (IS_NODE) {
  try {
    nodeLoader = await import('./nodeData.js');
    generatedCache = await nodeLoader.loadGenerated();
  } catch {
    nodeLoader = null;
  }
}

function loadResearch() {
  if (researchCache) return researchCache;
  researchCache = nodeLoader ? nodeLoader.loadResearch() : { chess: {}, enemies: {}, tokens: {}, stages: {}, waves: {} };
  return researchCache;
}

function asMap(v, idKey) {
  if (!v) return null;
  if (Array.isArray(v)) {
    const m = {};
    for (const x of v) if (x && x[idKey] != null) m[x[idKey]] = x;
    return m;
  }
  // Allow wrapper objects like { chess: {...} } or { enemies: {...} }
  return v;
}

function unwrap(v, key) {
  if (v && typeof v === 'object' && !Array.isArray(v) && v[key] && typeof v[key] === 'object' && Object.keys(v).length <= 4) return v[key];
  return v;
}

/**
 * Deep-freeze a normalised def (chess / enemy / token). Defs are cached and shared by every unit of every battle in
 * the process: a kit or content module that mutated one (`bb.x = …`, `def.rangeGrid.push(…)`) would silently change
 * later battles and break determinism. Frozen, such a write throws inside the (guarded) content code instead.
 * `raw` (the source record) and Sets (immunities) are left as they are.
 */
export function freezeDef(d) {
  if (!d || typeof d !== 'object' || Object.isFrozen(d)) return d;
  Object.freeze(d);
  for (const k of Object.keys(d)) {
    if (k === 'raw') continue;
    const v = d[k];
    if (v && typeof v === 'object' && !(v instanceof Set) && !(v instanceof Map)) freezeDef(v);
  }
  return d;
}

/**
 * A DataSource resolves ids to normalised defs. `raw` is `{ chess, enemies, tokens, stages, waves, backups? }`
 * (`backups` = data/backups.json `{ units, diy }`, the 补位 stand-ins: getChess(id, { standIn: true })).
 */
export class DataSource {
  constructor(raw = {}, fallback = null) {
    this.raw = {
      chess: asMap(unwrap(raw.chess, 'chess'), 'chessId') ?? {},
      enemies: asMap(unwrap(raw.enemies, 'enemies'), 'key') ?? {},
      tokens: asMap(unwrap(raw.tokens, 'tokens'), 'tokenId') ?? {},
      stages: asMap(unwrap(raw.stages, 'stages'), 'id') ?? {},
      waves: asMap(unwrap(raw.waves, 'waves'), 'id') ?? {},
      backups: raw.backups && typeof raw.backups === 'object' && raw.backups.units ? raw.backups : null,
      effects: raw.effects && typeof raw.effects === 'object' ? raw.effects : null,
    };
    this.fallback = fallback;
    this._chess = new Map();
    this._enemy = new Map();
    this._token = new Map();
    this._stage = new Map();
  }

  rawChess(id) { return this.raw.chess[id] ?? this.fallback?.rawChess(id) ?? null; }
  rawEnemy(key) {
    return this.raw.enemies[key] ?? this.raw.enemies['enemy_' + key] ?? this.raw.enemies[String(key).replace(/^enemy_/, '')] ?? this.fallback?.rawEnemy(key) ?? null;
  }
  /** A token record: data/tokens.json, else the 自选 picks' summons (data/backups.json `tokens`). */
  rawToken(id) { return this.raw.tokens[id] ?? this.fallback?.rawToken(id) ?? this.rawBackups()?.tokens?.[id] ?? null; }
  rawStage(id) { return this.raw.stages[id] ?? this.fallback?.rawStage(id) ?? null; }
  rawWave(id) { return this.raw.waves[id] ?? this.fallback?.rawWave(id) ?? null; }
  /** data/backups.json (`{ units, diy }`) of this source or its fallback, or null. */
  rawBackups() { return this.raw.backups ?? (typeof this.fallback?.rawBackups === 'function' ? this.fallback.rawBackups() : null); }
  /** A data/effects.json record of this source, its fallback, or the default game data (Node / the injected data). */
  rawEffect(id) {
    const own = this.raw.effects && Object.prototype.hasOwnProperty.call(this.raw.effects, id) ? this.raw.effects[id] : null;
    if (own) return own;
    if (typeof this.fallback?.rawEffect === 'function') return this.fallback.rawEffect(id);
    const fx = generatedCache && generatedCache.effects;
    return fx && Object.prototype.hasOwnProperty.call(fx, id) ? fx[id] : null;
  }
  /**
   * The 练度 (自持有) multipliers of tier `cultivate` (0–3): ATK / DEF / max HP from the effects.json CHAR_MAP record's
   * char_attribute_mul (shared/potential.js cultivateMul), or null.
   * @param {number} cultivate
   */
  cultivateMul(cultivate) { return cultivateMul((id) => this.rawEffect(id), cultivate); }

  /**
   * Chess def for the default loadout, or for `loadout` `{ skillIndex, moduleId }` (DESIGN §16; resolved with
   * resolveLoadout — illegal choices fall back to the default). `def.loadout` = the resolved loadout (null for records
   * without skill choices); `def.id` is always the chess id. Defs are cached per (id, resolved loadout).
   * `loadout.standIn === true`: the 补位 def of the chess (getStandIn) — its skill and module are the chess's backup
   * selection whatever `skillIndex` / `moduleId` say; a chess without a stand-in (PRESET, DIY, no backups data) gives
   * its own def for that loadout. `loadout.diy` (`{ charId, skillIndex, uniEquipId }`): the 自选 def of a DIY slot
   * (getDiy; null when the pick is not legal for that slot). `loadout.potential` (1–6): the record at that potential
   * (loadoutRecord; not for a stand-in).
   */
  getChess(id, loadout = null) {
    if (loadout && loadout.diy && typeof loadout.diy === 'object') return this.getDiy(id, loadout.diy, loadout.potential);
    if (loadout && loadout.standIn === true) {
      const sd = this.getStandIn(id);
      if (sd) return sd;
    }
    if (loadout == null && this._chess.has(id)) return this._chess.get(id);
    const r = this.rawChess(id);
    const lo = r ? resolveLoadout(r, loadout) : null;
    const key = id + loadoutKey(lo);
    if (this._chess.has(key)) return this._chess.get(key);
    let d = null;
    if (r) {
      d = normalizeChess({ chessId: id, ...loadoutRecord(r, lo) });
      d.loadout = lo;
      freezeDef(d);
    }
    this._chess.set(key, d);
    return d;
  }
  /**
   * The 补位 def of chess `id` (DATA.md §18): shared/standIn.js standInRecord of its record over rawBackups(), normalised
   * — `def.id` / `baseId` / `golden` / `tier` / `bonds` / `raw.garrisonIds` of the chess, every combat field of the
   * stand-in at the chess's status, `def.charId` the stand-in's, `def.standInFor` the replaced operator's charId,
   * `def.loadout` the backup selection (`isDefault`, `standIn: true`). Null for a chess without a stand-in (PRESET,
   * DIY) or when the data lacks it. Cached per id.
   */
  getStandIn(id) {
    const key = `${id}|standIn`;
    if (this._chess.has(key)) return this._chess.get(key);
    const r = this.rawChess(id);
    const rec = r ? standInRecord(r, this.rawBackups()) : null;
    let d = null;
    if (rec) {
      d = normalizeChess({ ...rec, chessId: id });
      d.loadout = { ...resolveLoadout(rec, null), standIn: true };
      freezeDef(d);
    }
    this._chess.set(key, d);
    return d;
  }
  /**
   * The 自选 def of DIY slot `id` (its `_a` or `_b` record) filled with `pick` (DATA.md §18): shared/diy.js diyRecordOf
   * over this source (chess records, backups.json), normalised — `def.id` / `baseId` / `golden` / `tier` / `bonds` (the
   * pick's derived ones) of the slot, every combat field of the operator at the slot's status with the pick's skill and
   * module, `def.charId` the operator's, `def.diyFor` the slot's base id, `def.loadout` = the selection (`isDefault`) with
   * `diy` = the checked pick, `def.tokenOwner` = its summons' variant key (shared/diy.js diyTokenOwner). Null for an
   * illegal pick (not a pick of the slot's tier, a prototype off its locked skill, an unknown skill or module — checkDiyPick)
   * or when the data lacks it. An owned pick is composed at `potential` (1–6, default 6; shared/diy.js diyRecordOf —
   * `def.loadout.potential`, its summons' variants follow); a prototype has none. Cached per (id, pick, potential).
   * @param {string} id
   * @param {{ charId?: string, skillIndex?: number|null, uniEquipId?: string|null }} pick
   * @param {number|null} [potential]
   */
  getDiy(id, pick, potential = null) {
    const pot = isPotential(potential) ? potential : POTENTIAL_DEFAULT;
    const key = `${id}|diy|${pick?.charId ?? ''}|${pick?.skillIndex ?? ''}|${pick?.uniEquipId ?? ''}|p${pot}`;
    if (this._chess.has(key)) return this._chess.get(key);
    const r = this.rawChess(id);
    const rec = r && r.isDiy ? diyRecordOf(r, pick, this, { potential: pot }) : null;
    let d = null;
    if (rec) {
      d = normalizeChess({ ...rec, chessId: id });
      const own = rec.diyProto ? POTENTIAL_DEFAULT : pot;
      d.loadout = {
        ...resolveLoadout(rec, null), potential: own, potentialIsDefault: own === POTENTIAL_DEFAULT,
        diy: { charId: rec.charId, skillIndex: rec.skill.index, uniEquipId: rec.module?.id ?? null },
      };
      d.tokenOwner = diyTokenOwner(rec.charId, rec.status);
      freezeDef(d);
    }
    this._chess.set(key, d);
    return d;
  }
  getEnemy(key) {
    if (this._enemy.has(key)) return this._enemy.get(key);
    const r = this.rawEnemy(key);
    const k = String(key).startsWith('enemy_') ? key : 'enemy_' + key;
    const d = r ? freezeDef(normalizeEnemy(k, r)) : null;
    this._enemy.set(key, d);
    return d;
  }
  /**
   * Token def; `ownerChessId` selects owner-specific stats when the data has them, `ownerLoadout` (`{ skillIndex,
   * moduleId }`, e.g. the owner def's `loadout`) the owner's selected skill / module: `variants[owner].bySkill[i]`
   * (token skill of that slot, count, sources) and `.byModule[id]` (module token attributes, trait, talents).
   * `def.sources` / `def.count` are those of the owner's loadout (a hand piece exists only when `sources` has more
   * than 'display'; PlayerState / the kits' skill summons read them from here).
   */
  getToken(id, ownerChessId = null, ownerLoadout = null) {
    if (ownerChessId && ownerLoadout && ownerLoadout.diy && typeof ownerLoadout.diy === 'object') return this.getDiyToken(id, ownerChessId, ownerLoadout.diy, ownerLoadout.potential);
    const olo = ownerChessId && ownerLoadout ? resolveLoadout(this.rawChess(ownerChessId), ownerLoadout) : null;
    const ck = id + '|' + (ownerChessId ?? '') + loadoutKey(olo);
    if (this._token.has(ck)) return this._token.get(ck);
    let r = this.rawToken(id);
    if (r && ownerChessId && !r.variants) {
      // research shape: byOwner[chessId] holds the owner-specific token record
      const byOwner = r.byOwner?.[ownerChessId] ?? r.statsByOwner?.[ownerChessId];
      if (byOwner) r = { ...r, ...(byOwner.stats ? byOwner : { stats: byOwner }) };
    }
    if (!r && ownerChessId) {
      // look inside the owner chess record
      const owner = this.rawChess(ownerChessId);
      const t = (owner?.tokens ?? []).find((x) => x && typeof x === 'object' && (x.tokenId ?? x.id) === id);
      if (t) r = t;
    }
    let owner = ownerChessId;
    if (r && r.variants && owner && !r.variants[owner]) {
      // fall back to the normal/golden sibling variant, then any variant
      const alt = String(owner).replace(/_b$/, '_a');
      owner = r.variants[alt] ? alt : null;
    }
    if (r && r.variants && !owner) owner = Object.keys(r.variants)[0] ?? null;
    let variant = r && r.variants && owner ? r.variants[owner] ?? null : null;
    // the owner's potential (0.2.2): the variant's talents (and counts) at it — before the skill / module parts merge
    if (variant && olo && olo.potentialIsDefault === false) variant = atPotential(variant, olo.potential);
    if (variant && olo && !olo.isDefault) {
      if (!olo.skillIsDefault && variant.bySkill && variant.bySkill[olo.skillIndex]) variant = { ...variant, ...variant.bySkill[olo.skillIndex] };
      if (!olo.moduleIsDefault && variant.byModule && variant.byModule[olo.moduleId]) variant = { ...variant, ...variant.byModule[olo.moduleId] };
    }
    const d = r ? freezeDef(normalizeToken(id, r, owner, variant)) : null;
    this._token.set(ck, d);
    return d;
  }
  /**
   * Token def of a summon of a 自选 piece: its record (data/backups.json `tokens`) with the variant of the owner form
   * (`<charId>@<statusKey of the slot record>`, shared/diy.js diyTokenOwner) and the pick as the owner's loadout —
   * `bySkill[skillIndex]` (the token skill / count / sources of that skill), `byModule[uniEquipId]` (module token
   * attributes, trait, talents), as getToken does for a chess owner's loadout. A token without a variant of that form
   * gets the record's defaults (`sources` null).
   * @param {string} id token id
   * @param {string} slotId the owner's DIY slot record id (`_a` / `_b`)
   * @param {{ charId?: string, skillIndex?: number|null, uniEquipId?: string|null }} pick the owner def's `loadout.diy`
   * @param {number|null} [potential] the owner's potential (its `loadout.potential`; default 6): the variant at it
   */
  getDiyToken(id, slotId, pick, potential = null) {
    const slot = this.rawChess(slotId);
    const owner = slot && typeof pick?.charId === 'string' ? diyTokenOwner(pick.charId, slot.status) : null;
    const pot = isPotential(potential) ? potential : POTENTIAL_DEFAULT;
    const ck = `${id}|diy|${owner ?? ''}|${pick?.skillIndex ?? ''}|${pick?.uniEquipId ?? ''}|p${pot}`;
    if (this._token.has(ck)) return this._token.get(ck);
    const r = this.rawToken(id);
    let variant = r && r.variants && owner ? r.variants[owner] ?? null : null;
    if (variant) variant = atPotential(variant, pot);
    if (variant) {
      const si = pick.skillIndex;
      if (Number.isInteger(si) && variant.bySkill && variant.bySkill[si]) variant = { ...variant, ...variant.bySkill[si] };
      const mid = pick.uniEquipId;
      if (typeof mid === 'string' && variant.byModule && variant.byModule[mid]) variant = { ...variant, ...variant.byModule[mid] };
    }
    const d = r ? freezeDef(normalizeToken(id, r, owner, variant)) : null;
    this._token.set(ck, d);
    return d;
  }
  getStage(id) {
    if (this._stage.has(id)) return this._stage.get(id);
    const d = normalizeStage(id, this.rawStage(id));
    this._stage.set(id, d);
    return d;
  }
  getWave(id) { return this.rawWave(id); }
  chessIds() {
    const s = new Set(Object.keys(this.raw.chess));
    if (this.fallback) for (const k of this.fallback.chessIds()) s.add(k);
    return [...s];
  }
  stageIds() {
    const s = new Set(Object.keys(this.raw.stages));
    if (this.fallback) for (const k of this.fallback.stageIds()) s.add(k);
    return [...s];
  }
  waveIds() {
    const s = new Set(Object.keys(this.raw.waves));
    if (this.fallback) for (const k of this.fallback.waveIds()) s.add(k);
    return [...s];
  }
}

let defaultSource = null;
let researchSource = null;

/** Research-only data source (Node: docs/research JSON; browsers: empty). Used as fallback and by tests. */
export function getResearchSource() {
  if (!researchSource) researchSource = new DataSource(loadResearch());
  return researchSource;
}

/** Whether generated (or injected) data with chess records is available. */
export function hasGeneratedData() {
  const g = generatedCache;
  return !!(g && g.chess && Object.keys(unwrap(g.chess, 'chess') || {}).length > 0);
}

/**
 * Default data source. Node: generated data with the research fallback. Browser: the data injected with setSimData
 * (no fallback: server and client battles must resolve every id identically), empty before that.
 */
export function getDefaultSource() {
  if (!defaultSource) defaultSource = injected || !nodeLoader ? new DataSource(generatedCache ?? {}, null) : new DataSource(generatedCache ?? {}, getResearchSource());
  return defaultSource;
}

/**
 * Inject the game data (browser: the fetched /data/*.json as `{ chess, enemies, tokens, stages, waves, bonds, items,
 * garrisons, bands, effects, … }`). It becomes the default source and the `getSimData()` object. Returns the new
 * default DataSource.
 * @param {object} data
 */
export function setSimData(data) {
  generatedCache = data && typeof data === 'object' ? data : null;
  injected = true;
  defaultSource = null;
  return getDefaultSource();
}

/** The raw data object behind the default source (injected or generated), or null. */
export function getSimData() {
  return generatedCache;
}

/** Reset caches (tests / hot reload after data regeneration). Node reloads data/*.json; browsers keep the injection. */
export async function reloadDataSources() {
  if (nodeLoader && !injected) generatedCache = await nodeLoader.reloadGenerated();
  defaultSource = null;
}

/** Build a DataSource from an injected object (maps or a DataSource instance). */
export function toDataSource(data) {
  if (!data) return getDefaultSource();
  if (data instanceof DataSource) return data;
  if (typeof data.getChess === 'function' && typeof data.getEnemy === 'function') return data;
  return new DataSource(data, getDefaultSource());
}

/**
 * Per-battle data view resolving operator loadouts from the battle's PlayerBattleInput units (DESIGN §16): `getChess(id)`
 * and `getToken(id, ownerChessId)` without an explicit loadout use the loadout the inputs give that chess id (an
 * operator entry without `skillIndex` / `moduleId` = the default). Everything else is the underlying source (prototype
 * delegation: caches stay shared). Within one field a chess id has one loadout per player (loadouts are per base chess);
 * when two players of a multi-player field give the same chess id different loadouts the first one wins for id-only
 * lookups (`view.loadoutConflicts` lists them) — callers that pass the unit's own loadout (`getChess(id, { skillIndex,
 * moduleId })`, `getToken(id, owner, ownerDef.loadout)`) are always exact. Returns `ds` itself when no unit carries a
 * loadout, and an existing view unchanged (`isLoadoutView`). Used by spec.js createBattleFromSpec and by
 * content/index.js installContent (every Battle, however constructed). An entry with `standIn: true` (补位) maps its
 * chess id to the stand-in def (`getChess(id, { standIn: true })`) the same way, and one with `diy` (自选: `{ charId,
 * skillIndex, uniEquipId }`) to its 自选 def (`getChess(id, { diy })`); a `potential` (1–6) rides along (0.2.2).
 * @param {object} ds DataSource
 * @param {object[]} players PlayerBattleInput[] (spec players)
 */
export function withUnitLoadouts(ds, players) {
  if (!ds || typeof ds.getChess !== 'function' || isLoadoutView(ds)) return ds;
  const map = new Map();
  const conflicts = new Set();
  let any = false;
  for (const p of Array.isArray(players) ? players : []) {
    for (const u of (p && Array.isArray(p.units) ? p.units : [])) {
      if (!u || u.kind === 'token' || typeof u.chessId !== 'string') continue;
      const diy = u.diy && typeof u.diy === 'object' ? u.diy : null;
      const pot = u.standIn !== true && isPotential(u.potential) ? u.potential : null;
      if (u.skillIndex != null || u.moduleId != null || u.standIn === true || diy || pot != null) any = true;
      const lo = { skillIndex: u.skillIndex ?? null, moduleId: u.moduleId ?? null };
      if (u.standIn === true) lo.standIn = true;
      if (diy) lo.diy = diy;
      if (pot != null) lo.potential = pot;
      const prev = map.get(u.chessId);
      if (!prev) map.set(u.chessId, lo);
      else if (prev.skillIndex !== lo.skillIndex || prev.moduleId !== lo.moduleId || !!prev.standIn !== !!lo.standIn
        || (prev.potential ?? null) !== (lo.potential ?? null)
        || JSON.stringify(prev.diy ?? null) !== JSON.stringify(lo.diy ?? null)) conflicts.add(u.chessId);
    }
  }
  if (!any) return ds;
  const view = Object.create(ds);
  view.getChess = (id, loadout = null) => ds.getChess(id, loadout ?? map.get(id) ?? null);
  if (typeof ds.getToken === 'function') {
    view.getToken = (id, owner = null, ownerLoadout = null) => ds.getToken(id, owner, ownerLoadout ?? (owner != null ? map.get(owner) ?? null : null));
  }
  view.loadoutConflicts = [...conflicts];
  return view;
}

/** Whether `ds` is a per-battle loadout view (withUnitLoadouts). */
export function isLoadoutView(ds) {
  return !!ds && typeof ds === 'object' && Object.prototype.hasOwnProperty.call(ds, 'loadoutConflicts');
}