export type TalentRelation = "gt" | "gte" | "eq";

export interface TalentPriority {
  type: "NA" | "E" | "Q";
  priority: number;
  level?: string;
  relationToNext?: TalentRelation;
}

export function normalizeTalentPriorities(talents: readonly TalentPriority[]): TalentPriority[] {
  const ordered = [...talents].sort((a, b) => a.priority - b.priority);
  return ordered.map((talent, index) => ({
    ...talent,
    priority: index + 1,
    relationToNext: index < ordered.length - 1 ? talent.relationToNext ?? "gt" : undefined,
  }));
}

export function reorderTalentPriorities(
  talents: readonly TalentPriority[],
  activeType: TalentPriority["type"],
  overType: TalentPriority["type"],
): TalentPriority[] {
  const ordered = normalizeTalentPriorities(talents);
  const from = ordered.findIndex((talent) => talent.type === activeType);
  const to = ordered.findIndex((talent) => talent.type === overType);
  if (from < 0 || to < 0 || from === to) return ordered;

  const relations = ordered.slice(0, -1).map((talent) => talent.relationToNext ?? "gt");
  const next = [...ordered];
  const [moved] = next.splice(from, 1);
  next.splice(to, 0, moved);

  return next.map((talent, index) => ({
    ...talent,
    priority: index + 1,
    relationToNext: index < next.length - 1 ? relations[index] : undefined,
  }));
}

export function talentRelationSymbol(relation?: TalentRelation): ">" | "≥" | "=" {
  return relation === "gte" ? "≥" : relation === "eq" ? "=" : ">";
}

export function talentTypeLabel(type: TalentPriority["type"]): string {
  return type === "E" ? "สกิลธาตุ" : type === "Q" ? "ท่าไม้ตาย" : "ตีปกติ";
}