// This self-contained factory also runs in the browser's QA context. It only
// subscribes to committed state; it never writes the game stores.
function createWeaponEvidenceRecorder(store, options = {}) {
  const capacity = options.capacity ?? 50_000;
  const clock = options.clock ?? Date.now;
  const initial = store.getState();
  const baselineEventId = initial.combatEvents?.at(-1)?.id ?? 0;
  let lastEventId = baselineEventId;
  let stopped = false;
  const events = [], gaps = [], mobSamples = [], auraSamples = [], errors = [];
  const signatures = new Map();
  let auraSignature = null;
  let discardedEvents = 0, discardedStates = 0;
  const retain = (array, entry, event = false) => {
    if (array.length < capacity) array.push(entry);
    else if (event) discardedEvents += 1;
    else discardedStates += 1;
  };
  const observe = (state) => {
    if (stopped) return;
    try {
      const fresh = (state.combatEvents ?? []).filter((event) => event.id > lastEventId);
      for (const event of fresh) {
        if (event.id > lastEventId + 1) gaps.push({ afterId: lastEventId, beforeId: event.id });
        retain(events, { ...event }, true);
        lastEventId = event.id;
      }
      const observedAt = clock();
      for (const mob of Object.values(state.mobs ?? {})) {
        const entry = {
          id: mob.id, name: mob.name, serverEntry: mob.serverEntry ?? null,
          sourceCreatureGuid: mob.sourceCreatureGuid ?? null,
          sourceEquipment: mob.sourceEquipment ? JSON.parse(JSON.stringify(mob.sourceEquipment)) : null,
          engaged: Boolean(mob.engaged), dead: Boolean(mob.dead),
          dualWieldEnabled: mob.dualWieldEnabled ?? null,
          nextEnemyOffhandAttackAt: mob.nextEnemyOffhandAttackAt ?? null,
          pendingExtraAttacks: mob.pendingExtraAttacks?.map((queued) => ({ ...queued })) ?? null,
          lastDamagedActorId: mob.lastDamagedActorId ?? null,
        };
        const signature = JSON.stringify(entry);
        if (signatures.get(mob.id) !== signature) {
          signatures.set(mob.id, signature);
          retain(mobSamples, { observedAt, ...entry });
        }
      }
      const active = (state.auras ?? []).filter((aura) =>
        /^(?:enemy-source-spell-(?:6742|6713|17230|3419)|enemy-control:source-spell-(?:5246|19134|20511|29544))$/.test(aura.definition?.id ?? '')).map((aura) => ({
        instanceId: aura.instanceId, definitionId: aura.definition.id,
        sourceId: aura.sourceId, targetId: aura.targetId,
        appliedAt: aura.appliedAt, expiresAt: aura.expiresAt, stacks: aura.stacks,
        dispelCategory: aura.definition.dispelCategory ?? null,
      }));
      const nextAuraSignature = JSON.stringify(active);
      if (nextAuraSignature !== auraSignature) {
        auraSignature = nextAuraSignature;
        retain(auraSamples, { observedAt, auras: active });
      }
    } catch (error) {
      if (errors.length < 10) errors.push(String(error?.message ?? error));
    }
  };
  observe(initial);
  const unsubscribe = store.subscribe(observe);
  return {
    stop() {
      if (!stopped) {
        observe(store.getState());
        stopped = true;
        unsubscribe();
      }
      return { baselineEventId, lastEventId, events, gaps, mobSamples, auraSamples,
        discardedEvents, discardedStates, errors,
        eventCoverage: 'Committed-store subscription with event-ID gap auditing; pre-start events excluded.',
        stateCoverage: 'Weapon and source-aura changes at store commits, including combat between route checkpoints.' };
    },
  };
}

module.exports = { createWeaponEvidenceRecorder };