import type {
  ActorNarrativeProfile,
  NpcDisclosureStage,
  SceneNarrativeDirective,
  VisibilitySlice,
} from '../../types';

type BuildSceneNarrativeDirectiveParams = {
  sceneId?: string | null;
  sceneName?: string | null;
  encounterId?: string | null;
  encounterName?: string | null;
  recentActions?: string[] | null;
  activeThreadIds?: string[] | null;
  foregroundCarrierIds?: string[] | null;
  visibilitySlice?: VisibilitySlice | null;
  encounterNarrativeProfile?: ActorNarrativeProfile | null;
  disclosureStage?: NpcDisclosureStage | null;
  isFirstMeaningfulContact?: boolean;
  affinity?: number | null;
};

function dedupeStrings(values: Array<string | null | undefined>, limit = 6) {
  return [...new Set(values.map((value) => value?.trim() ?? '').filter(Boolean))]
    .slice(0, limit);
}

function resolveRevealBudget(
  disclosureStage?: NpcDisclosureStage | null,
  isFirstMeaningfulContact?: boolean,
) {
  if (isFirstMeaningfulContact || disclosureStage === 'guarded') {
    return 'low' as const;
  }
  if (disclosureStage === 'partial' || disclosureStage === 'honest') {
    return 'medium' as const;
  }
  return 'high' as const;
}

function resolveEmotionalCadence(params: BuildSceneNarrativeDirectiveParams) {
  if ((params.affinity ?? 0) < -10) {
    return 'hostile' as const;
  }
  if (params.isFirstMeaningfulContact) {
    return 'curious' as const;
  }
  if ((params.visibilitySlice?.forbiddenFactIds.length ?? 0) > 3) {
    return 'mysterious' as const;
  }
  if ((params.affinity ?? 0) >= 45) {
    return 'intimate' as const;
  }
  if ((params.recentActions ?? []).some((action) => /战|伤|逃|追|压/u.test(action))) {
    return 'tense' as const;
  }
  return 'curious' as const;
}

export function buildSceneNarrativeDirective(
  params: BuildSceneNarrativeDirectiveParams,
) {
  const primaryPressure =
    params.encounterNarrativeProfile?.immediatePressure ||
    params.recentActions?.[0] ||
    `${params.sceneName ?? '当前场景'}里仍有未被说透的动静。`;

  return {
    primaryPressure,
    activeThreadIds: dedupeStrings(params.activeThreadIds ?? [], 4),
    foregroundActorIds: dedupeStrings([
      params.encounterId,
      params.encounterName,
    ], 3),
    foregroundCarrierIds: dedupeStrings(params.foregroundCarrierIds ?? [], 4),
    revealBudget: resolveRevealBudget(
      params.disclosureStage,
      params.isFirstMeaningfulContact,
    ),
    emotionalCadence: resolveEmotionalCadence(params),
  } satisfies SceneNarrativeDirective;
}