import type { FlowBoardDraft, FlowBoardSnapshotData } from "@/lib/db/schema";

export function isRecord(value: unknown): value is Record<string, unknown> {
  return typeof value === "object" && value !== null && !Array.isArray(value);
}

function normalizeRecord(value: unknown): Record<string, unknown> | null {
  return isRecord(value) ? value : null;
}

export function normalizeFlowBoardTitle(value: unknown) {
  const title = String(value || "").trim();
  return title.slice(0, 256) || "未命名流程白板";
}

export function normalizeFlowBoardSnapshot(
  value: unknown
): FlowBoardSnapshotData {
  const raw = isRecord(value) ? value : {};
  const updatedAt =
    typeof raw.updatedAt === "string" && raw.updatedAt.trim()
      ? raw.updatedAt
      : new Date().toISOString();

  return {
    children: Array.isArray(raw.children) ? raw.children.filter(isRecord) : [],
    viewport: normalizeRecord(raw.viewport),
    theme: normalizeRecord(raw.theme),
    updatedAt,
  };
}

export function mapFlowBoardDraft(draft: FlowBoardDraft) {
  return {
    id: draft.id,
    title: draft.title || "未命名流程白板",
    snapshot: draft.snapshot ?? { children: [] },
    createdAt: draft.createdAt?.toISOString() ?? null,
    updatedAt: draft.updatedAt?.toISOString() ?? null,
  };
}

export function mapFlowBoardDraftSummary(draft: FlowBoardDraft) {
  return {
    id: draft.id,
    title: draft.title || "未命名流程白板",
    createdAt: draft.createdAt?.toISOString() ?? null,
    updatedAt: draft.updatedAt?.toISOString() ?? null,
  };
}