import { mkdir, readFile, writeFile } from "node:fs/promises";
import { dirname, resolve } from "node:path";
import { createInterface } from "node:readline";
import {
  CLASSES,
  classById,
  contentCategoryForClass,
  type ClassId,
} from "../../src/app/characterCatalog";
import type { ContentCategoryId } from "../../src/app/contentCategories";
import {
  abilityById,
  abilitiesForCharacter,
  learnedAbilityForBuild,
  preloadAbilityCatalogsForClasses,
  type ResourceType,
} from "../../src/game/abilityCatalog";
import { aiHintsForAbility } from "../../src/game/abilityRules";
import { PLAYER_AGGRO_ID } from "../../src/game/aggro";
import { installCombatClock } from "../../src/game/combatClock";
import { companionResourceMaximum } from "../../src/game/combatActorAuthority";
import { subscribeCombatEvents } from "../../src/game/combatEvents";
import { subscribeCombatPresentation } from "../../src/game/combatPresentation";
import { resetCombatSpatialProvider } from "../../src/game/combatSpatial";
import { useCombatStore } from "../../src/game/combatStore";
import { dungeonEnemyScaling } from "../../src/game/dungeonBossScaling";
import { requireDungeonDefinition } from "../../src/game/dungeonRegistry";
import {
  resolvedAverageItemLevel,
  resolvedEquipmentItems,
  resolvedEquipmentStats,
} from "../../src/game/heirloomEquipment";
import {
  BOSS_TESTING_CATALOG,
  createBossTestingRoom,
  type TestableBoss,
} from "../../src/game/bossTesting";
import { clearMobRuntimeRegistry, setMobPosition } from "../../src/game/mobRuntimeRegistry";
import {
  advanceDungeonPartyCombat,
  partyCombatRangeBand,
  resetPartyRuntimeClock,
} from "../../src/game/partyRuntime";
import {
  clearPartyRuntimeRegistry,
  registerPartyRuntimePosition,
  updatePartyRuntimeTargetVisibility,
} from "../../src/game/partyRuntimeRegistry";
import {
  createConfiguredPartyMember,
  usePartyStore,
  type PartyMember,
} from "../../src/game/partyStore";
import { specializationsForClass } from "../../src/game/specializationCatalog";
import { BENCHMARK_POLICY_ID, BenchmarkController } from "../../src/game/benchmark/benchmarkController";
import { COMBAT_ROTATION_VERSION, rotationProfileFor } from "../../src/game/combatRotation";
import { subscribeRotationDecisions } from "../../src/game/rotationTelemetry";
import {
  DEFAULT_COMPANION_COOLDOWN_POLICY,
  installCompanionCooldownPolicy,
  type CompanionCooldownPolicy,
} from "../../src/game/companionCooldownPolicy";
import {
  CANONICAL_BENCHMARK_GEAR_PRESET_ID,
  loadSelectableBenchmarkBuilds,
  selectableBenchmarkBuildCatalog,
  type SelectableBenchmarkBuildCatalogEntry,
} from "../../src/game/benchmark/benchmarkBuilds";
import type {
  BenchmarkBuildDefinition,
  BenchmarkScenarioDefinition,
} from "../../src/game/benchmark/benchmarkTypes";

type BossCategory = "all" | "wow" | "rom";
type PartyCatalogSource = ContentCategoryId | "all";

interface BalanceLabConfig {
  readonly schemaVersion: 1;
  readonly source: ContentCategoryId;
  readonly level: number;
  readonly durationSeconds: number;
  readonly seeds: readonly number[];
  readonly partyBuildIds: readonly string[];
  readonly activeSlot: number;
  readonly bossCategory: BossCategory;
  readonly bossKeys?: readonly string[];
  readonly cooldownPolicy?: CompanionCooldownPolicy;
}

interface MutableAbilityMetrics {
  casts: number;
  rawDamage: number;
  effectiveDamage: number;
  rawHealing: number;
  effectiveHealing: number;
  overheal: number;
  absorbs: number;
  hits: number;
}

interface MutableMemberMetrics {
  readonly slot: number;
  readonly actorId: string;
  readonly build: BenchmarkBuildDefinition;
  damage: number;
  rawDamage: number;
  bossDamage: number;
  healing: number;
  rawHealing: number;
  overheal: number;
  healingReceived: number;
  absorbs: number;
  damageTaken: number;
  rawDamageTaken: number;
  absorbedDamageTaken: number;
  deathEvents: number;
  casts: number;
  minimumHealthPercent: number;
  readonly abilities: Map<string, MutableAbilityMetrics>;
  readonly rotationDecisions: Map<string, {
    profileId: string;
    ruleId: string;
    reason: string;
    abilityId: string;
    decisions: number;
  }>;
  gcdObservedMs: number;
  gcdBusyMs: number;
  readonly resourceSamples: Map<string, { samples: number; starved: number; capped: number }>;
}

const scenario = (durationMs: number): BenchmarkScenarioDefinition => ({
  id: "balance-lab-boss",
  version: 1,
  name: "Balance lab boss",
  description: "A selected five-member party against one isolated authored boss.",
  family: "mechanics",
  roles: ["damage", "tank", "healer"],
  durationMs,
  tickMs: 100,
  hostileTargets: 1,
  partyLayout: "melee",
  attacks: [],
});

function argument(name: string): string | null {
  const index = process.argv.indexOf(name);
  return index >= 0 ? process.argv[index + 1] ?? null : null;
}

function requiredArgument(name: string): string {
  const value = argument(name);
  if (!value) throw new Error(`Missing required ${name} argument.`);
  return value;
}

function safeNumber(value: unknown, fallback: number): number {
  const parsed = Number(value);
  return Number.isFinite(parsed) ? parsed : fallback;
}

function classIdsForSource(source: PartyCatalogSource): readonly ClassId[] {
  return CLASSES
    .map((definition) => definition.id)
    .filter((classId) => source === "all" || contentCategoryForClass(classId) === source);
}

function bossCatalogRows() {
  return BOSS_TESTING_CATALOG.map((boss) => ({
    key: boss.key,
    name: boss.name,
    dungeonId: boss.dungeonId,
    dungeonTitle: boss.dungeonTitle,
    category: boss.category,
  }));
}

function resolvedGearSummary(build: SelectableBenchmarkBuildCatalogEntry) {
  const specialization = specializationsForClass(build.classId)
    .find((definition) => definition.displayName === build.orientation);
  const context = {
    ownerId: `balance-lab-catalog:${build.id}`,
    ownerKind: "player" as const,
    classId: build.classId,
    specializationId: specialization?.id ?? null,
    role: build.role,
    level: build.level,
  };
  const items = resolvedEquipmentItems({}, [], context);
  return {
    presetId: CANONICAL_BENCHMARK_GEAR_PRESET_ID,
    model: "synthetic-specialization-heirloom-v1",
    itemCount: items.length,
    averageItemLevel: resolvedAverageItemLevel({}, [], context),
    itemLevels: [...new Set(items.map((item) => item.itemLevel))].sort((left, right) => left - right),
    stats: resolvedEquipmentStats({}, [], context),
  };
}

async function writeJson(path: string, value: unknown): Promise<void> {
  const absolute = resolve(path);
  await mkdir(dirname(absolute), { recursive: true });
  await writeFile(absolute, `${JSON.stringify(value, null, 2)}\n`, "utf8");
}

function catalogPayload(source: PartyCatalogSource, level: number) {
  if (!["wow", "coa", "rom", "all"].includes(source)) throw new Error(`Unknown party source: ${source}`);
  const builds = selectableBenchmarkBuildCatalog(level, classIdsForSource(source));
  return {
    schemaVersion: 1,
    policyId: BENCHMARK_POLICY_ID,
    rotationVersion: COMBAT_ROTATION_VERSION,
    level: builds[0]?.level ?? level,
    source,
    builds: builds.map((build) => ({
      id: build.id,
      source: build.source,
      classId: build.classId,
      className: classById(build.classId).name,
      role: build.role,
      specialization: build.orientation,
      specializationId: build.specializationId ?? null,
      readinessStatus: build.readinessStatus ?? null,
      characterName: build.characterName ?? null,
      talentBuildId: build.talentBuildId ?? null,
      talentBuildName: build.talentBuildName ?? null,
      talentBuildSource: build.talentBuildSource ?? null,
      talentBuildSourcePointCount: build.talentBuildSourcePointCount ?? null,
      talentBuildSourcePointsRetained: build.talentBuildSourcePointsRetained ?? null,
      talentBuildFallbackPointCount: build.talentBuildFallbackPointCount ?? null,
      defaultTalentBuild: build.defaultTalentBuild ?? true,
      label: `${classById(build.classId).name} — ${build.orientation} (${build.role})${build.talentBuildName ? ` — ${build.talentBuildName}` : ""}`,
      gear: resolvedGearSummary(build),
    })),
    bosses: bossCatalogRows(),
  };
}

async function writeCatalog(): Promise<void> {
  const level = Math.trunc(safeNumber(argument("--level"), 60));
  const source = (argument("--source") ?? "wow") as PartyCatalogSource;
  await writeJson(requiredArgument("--output"), catalogPayload(source, level));
}

function selectedBosses(config: BalanceLabConfig): readonly TestableBoss[] {
  const requested = new Set(config.bossKeys ?? []);
  const rows = BOSS_TESTING_CATALOG.filter((boss) => (
    (config.bossCategory === "all" || boss.category === config.bossCategory)
    && (!requested.size || requested.has(boss.key))
  ));
  if (!rows.length) throw new Error("No bosses matched the requested boss filters.");
  if (requested.size) {
    const found = new Set(rows.map((boss) => boss.key));
    const missing = [...requested].filter((key) => !found.has(key));
    if (missing.length) throw new Error(`Unknown or category-excluded boss keys: ${missing.join(", ")}`);
  }
  return rows;
}

function configuredCompanion(
  build: BenchmarkBuildDefinition,
  slot: number,
  level: number,
  seed: string,
): PartyMember {
  const specialization = specializationsForClass(build.classId)
    .find((definition) => definition.displayName === build.orientation);
  return createConfiguredPartyMember({
    name: build.characterName ?? `${classById(build.classId).name} ${build.orientation}`,
    classId: build.classId,
    secondaryClassId: build.secondaryClassId,
    specialization: build.orientation,
    specializationId: specialization?.id ?? null,
    talentTreeId: specialization?.id ?? "",
    talentRanks: build.talentRanks,
    role: build.role,
  }, level, slot, seed);
}

function blankAbility(): MutableAbilityMetrics {
  return {
    casts: 0,
    rawDamage: 0,
    effectiveDamage: 0,
    rawHealing: 0,
    effectiveHealing: 0,
    overheal: 0,
    absorbs: 0,
    hits: 0,
  };
}

function abilityMetrics(member: MutableMemberMetrics, abilityId: string | undefined): MutableAbilityMetrics {
  const key = abilityId ?? "unknown";
  const existing = member.abilities.get(key);
  if (existing) return existing;
  const created = blankAbility();
  member.abilities.set(key, created);
  return created;
}

function abilityProducesAttributedCombatEvent(abilityId: string | undefined): boolean {
  const ability = abilityId ? abilityById(abilityId) : null;
  return ability?.effects.some((effect) => [
    "damage", "dot", "finisher-damage", "execute", "heal", "hot", "shield", "resurrection",
  ].includes(effect.kind)) ?? true;
}

function currentHealth(actorId: string): readonly [number, number] {
  const combat = useCombatStore.getState();
  if (actorId === PLAYER_AGGRO_ID) return [combat.health, combat.maxHealth];
  const member = usePartyStore.getState().members.find((candidate) => candidate.id === actorId);
  return [member?.health ?? 0, member?.maxHealth ?? 1];
}

function availableAbilities(build: BenchmarkBuildDefinition) {
  const specialization = specializationsForClass(build.classId)
    .find((definition) => definition.displayName === build.orientation);
  const profile = rotationProfileFor(build.classId, specialization?.id, build.orientation);
  return abilitiesForCharacter(build.classId, build.secondaryClassId)
    .filter((ability) => !ability.passive)
    .map((ability) => {
      const ranked = learnedAbilityForBuild(ability, build.level, build.talentRanks);
      if (!ranked) return null;
      if (ranked.effects.every((effect) => effect.kind === "unsupported" || effect.kind === "scripted")) return null;
      const hints = aiHintsForAbility(ranked);
      const rotationPriority = profile?.abilityPriority.indexOf(ranked.name) ?? -1;
      const conditional = hints.categories.some((category) => [
        "area-damage", "control", "dispel", "emergency-heal", "execute", "interrupt",
        "mitigation", "resurrection", "taunt",
      ].includes(category));
      return {
        abilityId: ranked.id,
        abilityName: ranked.name,
        icon: ranked.icon,
        categories: hints.categories,
        cooldownSeconds: ranked.cooldownMs / 1_000,
        rotationProfileId: profile?.id ?? null,
        rotationPriority: rotationPriority >= 0 ? rotationPriority + 1 : null,
        expectedUsage: conditional ? "conditional" : rotationPriority >= 0 ? "profile" : "available",
      };
    })
    .filter((ability) => ability !== null)
    .sort((left, right) => left.abilityName.localeCompare(right.abilityName));
}

function serializedMember(
  metrics: MutableMemberMetrics,
  activeSeconds: number,
) {
  const [health, maxHealth] = currentHealth(metrics.actorId);
  return {
    slot: metrics.slot,
    activePlayer: metrics.actorId === PLAYER_AGGRO_ID,
    actorId: metrics.actorId,
    buildId: metrics.build.id,
    characterName: metrics.build.characterName ?? null,
    talentBuildId: metrics.build.talentBuildId ?? null,
    talentBuildName: metrics.build.talentBuildName ?? null,
    talentBuildSource: metrics.build.talentBuildSource ?? null,
    talentBuildSourcePointCount: metrics.build.talentBuildSourcePointCount ?? null,
    talentBuildSourcePointsRetained: metrics.build.talentBuildSourcePointsRetained ?? null,
    talentBuildFallbackPointCount: metrics.build.talentBuildFallbackPointCount ?? null,
    classId: metrics.build.classId,
    className: classById(metrics.build.classId).name,
    specialization: metrics.build.orientation,
    role: metrics.build.role,
    damage: metrics.damage,
    rawDamage: metrics.rawDamage,
    bossDamage: metrics.bossDamage,
    dps: metrics.damage / Math.max(0.1, activeSeconds),
    bossDps: metrics.bossDamage / Math.max(0.1, activeSeconds),
    healing: metrics.healing,
    rawHealing: metrics.rawHealing,
    overheal: metrics.overheal,
    hps: metrics.healing / Math.max(0.1, activeSeconds),
    healingReceived: metrics.healingReceived,
    hpsReceived: metrics.healingReceived / Math.max(0.1, activeSeconds),
    absorbs: metrics.absorbs,
    damageTaken: metrics.damageTaken,
    rawDamageTaken: metrics.rawDamageTaken,
    absorbedDamageTaken: metrics.absorbedDamageTaken,
    dtps: metrics.damageTaken / Math.max(0.1, activeSeconds),
    deathEvents: metrics.deathEvents,
    alive: health > 0,
    finalHealth: health,
    maxHealth,
    minimumHealthPercent: metrics.minimumHealthPercent,
    casts: metrics.casts,
    gcdUptimePercent: metrics.gcdObservedMs > 0 ? metrics.gcdBusyMs / metrics.gcdObservedMs * 100 : null,
    resources: [...metrics.resourceSamples.entries()].map(([resource, samples]) => ({
      resource,
      samples: samples.samples,
      starvedPercent: samples.starved / Math.max(1, samples.samples) * 100,
      cappedPercent: samples.capped / Math.max(1, samples.samples) * 100,
    })).sort((left, right) => left.resource.localeCompare(right.resource)),
    rotationDecisions: [...metrics.rotationDecisions.values()]
      .sort((left, right) => right.decisions - left.decisions
        || left.profileId.localeCompare(right.profileId)
        || left.ruleId.localeCompare(right.ruleId)
        || left.abilityId.localeCompare(right.abilityId)),
    availableAbilities: availableAbilities(metrics.build),
    abilities: [...metrics.abilities.entries()]
      .map(([abilityId, ability]) => ({ abilityId, ...ability }))
      .sort((left, right) => right.effectiveDamage - left.effectiveDamage
        || right.effectiveHealing - left.effectiveHealing
        || left.abilityId.localeCompare(right.abilityId)),
  };
}

async function runBoss(
  config: BalanceLabConfig,
  builds: readonly BenchmarkBuildDefinition[],
  boss: TestableBoss,
  seed: number,
) {
  const sourceDungeon = requireDungeonDefinition(boss.dungeonId);
  const testingRoom = createBossTestingRoom(sourceDungeon, boss).definition;
  const entity = testingRoom.entities[boss.entityId];
  if (!entity) throw new Error(`Boss entity ${boss.key} is missing from its testing room.`);
  const bossActorId = `${boss.spawn.id}:balance-${seed}`;
  const activeBuild = builds[config.activeSlot];
  const durationMs = Math.max(1_000, Math.min(600_000, Math.round(config.durationSeconds * 1_000)));
  const specialization = specializationsForClass(activeBuild.classId)
    .find((definition) => definition.displayName === activeBuild.orientation);
  const scaling = dungeonEnemyScaling(
    testingRoom,
    entity,
    bossActorId,
    activeBuild.level,
    testingRoom.defaultDifficultyId,
    1,
    activeBuild.source,
  );

  clearMobRuntimeRegistry();
  clearPartyRuntimeRegistry();
  resetPartyRuntimeClock();
  resetCombatSpatialProvider();
  let now = 1_000_000;
  const restoreClock = installCombatClock(() => now);
  const companions = builds
    .map((build, slot) => ({ build, slot }))
    .filter(({ slot }) => slot !== config.activeSlot)
    .map(({ build, slot }) => configuredCompanion(build, slot, activeBuild.level, `${seed}:${boss.key}`));
  const actorIds = builds.map((_, slot) => (
    slot === config.activeSlot
      ? PLAYER_AGGRO_ID
      : companions.find((member) => member.id.includes(`-${slot}-`))?.id ?? ""
  ));
  const memberMetrics = builds.map((build, slot): MutableMemberMetrics => ({
    slot,
    actorId: actorIds[slot],
    build,
    damage: 0,
    rawDamage: 0,
    bossDamage: 0,
    healing: 0,
    rawHealing: 0,
    overheal: 0,
    healingReceived: 0,
    absorbs: 0,
    damageTaken: 0,
    rawDamageTaken: 0,
    absorbedDamageTaken: 0,
    deathEvents: 0,
    casts: 0,
    minimumHealthPercent: 1,
    abilities: new Map(),
    rotationDecisions: new Map(),
    gcdObservedMs: 0,
    gcdBusyMs: 0,
    resourceSamples: new Map(),
  }));
  const byActorId = new Map(memberMetrics.map((metrics) => [metrics.actorId, metrics]));
  const actorAlive = new Map<string, boolean>();
  const bossAbilities = new Map<string, MutableAbilityMetrics>();
  const pressureWindows = new Set<number>();
  const healerThroughputWindows = new Set<number>();
  const combatWindow = (occurredAt: number) => Math.max(0, Math.floor((occurredAt - 1_000_000) / 5_000));
  const stopRotationDecisions = subscribeRotationDecisions((event) => {
    const member = byActorId.get(event.actorId);
    if (!member) return;
    const key = `${event.profileId}\u0000${event.ruleId}\u0000${event.abilityId}`;
    const current = member.rotationDecisions.get(key);
    if (current) current.decisions += 1;
    else member.rotationDecisions.set(key, {
      profileId: event.profileId,
      ruleId: event.ruleId,
      reason: event.reason,
      abilityId: event.abilityId,
      decisions: 1,
    });
  });
  // Instant resource, aura, pet, and summon actions do not produce the damage,
  // healing, absorb, or cast events used by the original report collector.
  // Count their completed release once so Balance Lab does not label working
  // actions such as Bloodrage and Feral Spirit as available-but-unused.
  const stopPresentation = subscribeCombatPresentation((message) => {
    if (message.kind !== "event" || message.event.phase !== "release") return;
    const source = byActorId.get(message.event.sourceActorId);
    if (!source || abilityProducesAttributedCombatEvent(message.event.abilityId)) return;
    source.casts += 1;
    abilityMetrics(source, message.event.abilityId).casts += 1;
  });
  const stopEvents = subscribeCombatEvents((event) => {
    const source = byActorId.get(event.sourceActorId);
    const target = byActorId.get(event.targetActorId);
    if (event.kind === "cast" && source) {
      if (!abilityProducesAttributedCombatEvent(event.abilityId)) return;
      source.casts += 1;
      abilityMetrics(source, event.abilityId).casts += 1;
    } else if (event.kind === "damage") {
      if (source && !target) {
        source.rawDamage += event.rawAmount;
        source.damage += event.effectiveAmount;
        if (event.targetActorId === bossActorId) source.bossDamage += event.effectiveAmount;
        const ability = abilityMetrics(source, event.abilityId);
        ability.rawDamage += event.rawAmount;
        ability.effectiveDamage += event.effectiveAmount;
        ability.hits += 1;
      }
      if (target && !source) {
        target.rawDamageTaken += event.rawAmount;
        target.damageTaken += event.effectiveAmount;
        target.absorbedDamageTaken += event.absorbed;
        const key = event.abilityId ?? "unknown";
        const ability = bossAbilities.get(key) ?? blankAbility();
        ability.rawDamage += event.rawAmount;
        ability.effectiveDamage += event.effectiveAmount;
        ability.absorbs += event.absorbed;
        ability.hits += 1;
        bossAbilities.set(key, ability);
        if (event.effectiveAmount > 0) pressureWindows.add(combatWindow(event.occurredAt));
      }
    } else if (event.kind === "healing") {
      if (source) {
        source.rawHealing += event.rawAmount;
        source.healing += event.effectiveAmount;
        source.overheal += event.overheal;
        const ability = abilityMetrics(source, event.abilityId);
        ability.rawHealing += event.rawAmount;
        ability.effectiveHealing += event.effectiveAmount;
        ability.overheal += event.overheal;
        ability.hits += 1;
        if (source.build.role === "healer" && event.effectiveAmount > 0) {
          healerThroughputWindows.add(combatWindow(event.occurredAt));
        }
      }
      if (target) target.healingReceived += event.effectiveAmount;
    } else if (event.kind === "absorb" && source) {
      source.absorbs += event.effectiveAmount;
      abilityMetrics(source, event.abilityId).absorbs += event.effectiveAmount;
      if (source.build.role === "healer" && event.effectiveAmount > 0) {
        healerThroughputWindows.add(combatWindow(event.occurredAt));
      }
    }
  });

  let elapsedMs = 0;
  let outcome: "defeated" | "wipe" | "timeout" = "timeout";
  try {
    const combat = useCombatStore.getState();
    combat.initializeCharacter({
      classId: activeBuild.classId,
      secondaryClassId: activeBuild.secondaryClassId,
      specializationId: specialization?.id,
      role: activeBuild.role,
      level: activeBuild.level,
      talentRanks: activeBuild.talentRanks,
      inventory: activeBuild.inventory,
      equipment: activeBuild.equipment,
    });
    combat.setPlayerPosition([-2, 0, 0]);
    usePartyStore.setState({
      seed: `${seed}:${boss.key}`,
      playerRole: activeBuild.role,
      partySize: 5,
      categoryId: config.source,
      members: companions,
      command: "defend",
      selectedMemberId: null,
      selfSelected: false,
      routeBlocked: false,
      activeMobId: null,
      objectiveBossId: null,
      memberTargetIds: {},
    });
    combat.synchronizeActors();
    for (const metrics of memberMetrics) {
      actorAlive.set(metrics.actorId, currentHealth(metrics.actorId)[0] > 0);
    }
    combat.registerMob(bossActorId, {
      name: entity.name,
      boss: true,
      serverEntry: entity.combat?.serverEntry,
      ...scaling,
      attacks: entity.combat?.attacks,
      xpReward: 0,
    });
    setMobPosition(bossActorId, [0, 0, 0]);
    for (const member of companions) {
      registerPartyRuntimePosition(member.id, [-partyCombatRangeBand(member).preferred, 0, 0]);
      updatePartyRuntimeTargetVisibility(member.id, bossActorId, true);
    }
    combat.selectMob(bossActorId);
    const tank = memberMetrics.find((member) => member.build.role === "tank") ?? memberMetrics[0];
    combat.damageMob(bossActorId, 1, now, {
      actorId: tank.actorId,
      role: "tank",
      abilityId: "balance-lab-pull",
    }, "physical");
    const controller = new BenchmarkController();
    const runScenario = scenario(durationMs);
    for (elapsedMs = 100; elapsedMs <= durationMs; elapsedMs += 100) {
      now = 1_000_000 + elapsedMs;
      combat.tick(0.1, now);
      combat.advanceMobCombat(now);
      advanceDungeonPartyCombat(now);
      controller.act(now, activeBuild.role, runScenario, false);
      for (const member of usePartyStore.getState().members) {
        const metrics = byActorId.get(member.id);
        if (!metrics) continue;
        // Dead companions cannot act or gain/spend resources. Sampling them until
        // the fight ends makes an early death look like an idle/resource deadlock.
        if (currentHealth(member.id)[0] <= 0) continue;
        metrics.gcdObservedMs += 100;
        if (member.globalCooldownEndsAt > now || member.activeCast) metrics.gcdBusyMs += 100;
        const resources = new Set<ResourceType>([
          ...(Object.keys(member.resourcePools) as ResourceType[]),
          member.resourceType,
        ]);
        for (const resource of resources) {
          const maximum = companionResourceMaximum(member, resource);
          if (maximum <= 0) continue;
          const value = member.resourcePools[resource] ?? (resource === member.resourceType ? member.resource : 0);
          const sample = metrics.resourceSamples.get(resource) ?? { samples: 0, starved: 0, capped: 0 };
          sample.samples += 1;
          if (value / maximum <= 0.1) sample.starved += 1;
          if (value / maximum >= 0.95) sample.capped += 1;
          metrics.resourceSamples.set(resource, sample);
        }
      }
      for (const metrics of memberMetrics) {
        const [health, maxHealth] = currentHealth(metrics.actorId);
        const alive = health > 0;
        if ((actorAlive.get(metrics.actorId) ?? alive) && !alive) metrics.deathEvents += 1;
        actorAlive.set(metrics.actorId, alive);
        metrics.minimumHealthPercent = Math.min(
          metrics.minimumHealthPercent,
          maxHealth > 0 ? Math.max(0, health / maxHealth) : 0,
        );
      }
      const state = useCombatStore.getState();
      if (state.mobs[bossActorId]?.dead) {
        outcome = "defeated";
        break;
      }
      if (memberMetrics.every((metrics) => currentHealth(metrics.actorId)[0] <= 0)) {
        outcome = "wipe";
        break;
      }
    }
    const activeSeconds = Math.min(durationMs, elapsedMs) / 1_000;
    const mob = useCombatStore.getState().mobs[bossActorId];
    const members = memberMetrics.map((metrics) => serializedMember(metrics, activeSeconds));
    const incomingDamage = members.reduce((total, member) => total + member.damageTaken, 0);
    const rawIncomingDamage = members.reduce((total, member) => total + member.rawDamageTaken, 0);
    const partyDamage = members.reduce((total, member) => total + member.damage, 0);
    const bossDamage = members.reduce((total, member) => total + member.bossDamage, 0);
    const healerResponseWindows = [...pressureWindows].filter((window) => (
      healerThroughputWindows.has(window - 1)
      || healerThroughputWindows.has(window)
      || healerThroughputWindows.has(window + 1)
    )).length;
    return {
      bossKey: boss.key,
      bossName: boss.name,
      bossCategory: boss.category,
      dungeonId: boss.dungeonId,
      dungeonTitle: boss.dungeonTitle,
      seed,
      outcome,
      elapsedSeconds: activeSeconds,
      timeToDefeatSeconds: outcome === "defeated" ? activeSeconds : null,
      bossLevel: scaling.level,
      bossMaxHealth: scaling.maxHealth,
      bossRemainingHealth: mob?.health ?? 0,
      partyDamage,
      bossDamage,
      partyDps: partyDamage / Math.max(0.1, activeSeconds),
      bossDpsTaken: bossDamage / Math.max(0.1, activeSeconds),
      incomingDamage,
      rawIncomingDamage,
      incomingDtps: incomingDamage / Math.max(0.1, activeSeconds),
      pressureWindows: pressureWindows.size,
      healerThroughputWindows: healerThroughputWindows.size,
      healerResponseWindows,
      healerResponseRate: healerResponseWindows / Math.max(1, pressureWindows.size),
      deaths: members.filter((member) => !member.alive).length,
      deathEvents: members.reduce((total, member) => total + member.deathEvents, 0),
      bossAttacks: mob?.attackRevision ?? 0,
      members,
      bossAbilities: [...bossAbilities.entries()]
        .map(([abilityId, ability]) => ({ abilityId, ...ability }))
        .sort((left, right) => right.effectiveDamage - left.effectiveDamage
          || left.abilityId.localeCompare(right.abilityId)),
    };
  } finally {
    stopRotationDecisions();
    stopPresentation();
    stopEvents();
    restoreClock();
    clearMobRuntimeRegistry();
    clearPartyRuntimeRegistry();
    resetPartyRuntimeClock();
    resetCombatSpatialProvider();
  }
}

async function simulateConfig(config: BalanceLabConfig, output: string): Promise<void> {
  if (config.schemaVersion !== 1) throw new Error(`Unsupported config schema: ${config.schemaVersion}`);
  if (config.partyBuildIds.length !== 5) throw new Error("A balance-lab party must contain exactly five builds.");
  if (!Number.isInteger(config.activeSlot) || config.activeSlot < 0 || config.activeSlot >= 5) {
    throw new Error("activeSlot must be an integer from 0 through 4.");
  }
  if (!config.seeds.length) throw new Error("At least one simulation seed is required.");
  installCompanionCooldownPolicy(config.cooldownPolicy ?? DEFAULT_COMPANION_COOLDOWN_POLICY);
  const catalog = selectableBenchmarkBuildCatalog(config.level, classIdsForSource(config.source));
  const catalogById = new Map(catalog.map((build) => [build.id, build]));
  const selectedClassIds = [...new Set(config.partyBuildIds.map((id) => {
    const entry = catalogById.get(id);
    if (!entry) throw new Error(`Unknown ${config.source} party build: ${id}`);
    return entry.classId;
  }))];
  const availableBuilds = await loadSelectableBenchmarkBuilds(config.level, selectedClassIds);
  const byId = new Map(availableBuilds.map((build) => [build.id, build]));
  const builds = config.partyBuildIds.map((id) => {
    const build = byId.get(id);
    if (!build) throw new Error(`Unknown ${config.source} party build: ${id}`);
    return build;
  });
  await preloadAbilityCatalogsForClasses(builds.map((build) => build.classId));
  const bosses = selectedBosses(config);
  const runs = [];
  let completed = 0;
  const total = bosses.length * config.seeds.length;
  for (const boss of bosses) {
    for (const seed of config.seeds) {
      runs.push(await runBoss(config, builds, boss, seed));
      completed += 1;
      if (completed === 1 || completed === total || completed % 10 === 0) {
        process.stderr.write(`[balance-lab] ${completed}/${total} ${boss.name} seed ${seed}\n`);
      }
    }
  }
  await writeJson(output, {
    schemaVersion: 1,
    generatedAt: new Date().toISOString(),
    engine: "live-typescript-runtime",
    policyId: BENCHMARK_POLICY_ID,
    rotationVersion: COMBAT_ROTATION_VERSION,
    config: {
      ...config,
      level: builds[0]?.level ?? config.level,
    },
    party: builds.map((build, slot) => ({
      slot,
      activePlayer: slot === config.activeSlot,
      buildId: build.id,
      characterName: build.characterName ?? null,
      talentBuildId: build.talentBuildId ?? null,
      talentBuildName: build.talentBuildName ?? null,
      talentBuildSource: build.talentBuildSource ?? null,
      talentBuildSourcePointCount: build.talentBuildSourcePointCount ?? null,
      talentBuildSourcePointsRetained: build.talentBuildSourcePointsRetained ?? null,
      talentBuildFallbackPointCount: build.talentBuildFallbackPointCount ?? null,
      classId: build.classId,
      className: classById(build.classId).name,
      specialization: build.orientation,
      role: build.role,
    })),
    bossCount: bosses.length,
    runCount: runs.length,
    runs,
  });
}

async function simulate(): Promise<void> {
  const config = JSON.parse(await readFile(resolve(requiredArgument("--config")), "utf8")) as BalanceLabConfig;
  await simulateConfig(config, requiredArgument("--output"));
}

async function serveSession(): Promise<void> {
  const level = Math.trunc(safeNumber(argument("--level"), 60));
  const source = (argument("--source") ?? "wow") as PartyCatalogSource;
  process.stdout.write(`${JSON.stringify(catalogPayload(source, level))}\n`);
  const lines = createInterface({ input: process.stdin, crlfDelay: Infinity });
  for await (const line of lines) {
    if (!line.trim()) continue;
    const request = JSON.parse(line) as {
      readonly close?: boolean;
      readonly config?: string;
      readonly output?: string;
    };
    if (request.close) {
      process.stdout.write(`${JSON.stringify({ ok: true, closed: true })}\n`);
      lines.close();
      return;
    }
    if (!request.config || !request.output) throw new Error("A session simulation requires config and output paths.");
    const config = JSON.parse(await readFile(resolve(request.config), "utf8")) as BalanceLabConfig;
    await simulateConfig(config, request.output);
    process.stdout.write(`${JSON.stringify({ ok: true })}\n`);
  }
}

async function main(): Promise<void> {
  const command = process.argv[2];
  if (command === "catalog") await writeCatalog();
  else if (command === "simulate") await simulate();
  else if (command === "session") await serveSession();
  else throw new Error("Usage: vite-node scripts/balance-lab/runtime.ts <catalog|simulate|session> [options]");
}

main().catch((error) => {
  console.error(error instanceof Error ? error.stack ?? error.message : error);
  process.exitCode = 1;
});