export const TOOLS_ORDER_CHANGE_EVENT = "extensions-order-change";

const TOOLS_ORDER_KEY = "extensions-order";

export function getToolsOrder(): string[] {
  if (typeof window === "undefined") return [];
  try {
    const raw = window.localStorage.getItem(TOOLS_ORDER_KEY);
    if (!raw) return [];
    const parsed = JSON.parse(raw);
    return Array.isArray(parsed)
      ? parsed.filter((id) => typeof id === "string")
      : [];
  } catch {
    return [];
  }
}

export function setToolsOrder(order: string[]) {
  if (typeof window === "undefined") return;
  try {
    window.localStorage.setItem(TOOLS_ORDER_KEY, JSON.stringify(order));
    window.dispatchEvent(
      new CustomEvent(TOOLS_ORDER_CHANGE_EVENT, { detail: order }),
    );
  } catch {
    // localStorage unavailable / quota — ignore, order is best-effort
  }
}

export function applyToolsOrder<T extends { id: string }>(
  items: T[],
  savedOrder: string[],
): T[] {
  if (savedOrder.length === 0) return items;
  const idToItem = new Map(items.map((item) => [item.id, item]));
  const ordered: T[] = [];
  for (const id of savedOrder) {
    const item = idToItem.get(id);
    if (item) {
      ordered.push(item);
      idToItem.delete(id);
    }
  }
  for (const item of idToItem.values()) {
    ordered.push(item);
  }
  return ordered;
}