type CreateCommentRequestBody = {
  parentId?: number | null;
  guestDisplayName?: string;
  guestEmail?: string;
  guestIsAnonymous?: boolean;
  body: unknown;
};

export type ParsedCreateCommentInput = {
  parentId: number | null;
  guestDisplayName?: string;
  guestEmail?: string;
  guestIsAnonymous?: boolean;
  body: string;
};

export function parsePublicPostCreateCommentBody(body: CreateCommentRequestBody): ParsedCreateCommentInput {
  if (typeof body.body !== "string") {
    throw createError({ statusCode: 400, statusMessage: "无效请求" });
  }
  return {
    parentId: parseParentId(body.parentId),
    guestDisplayName: typeof body.guestDisplayName === "string" ? body.guestDisplayName : undefined,
    guestEmail: typeof body.guestEmail === "string" ? body.guestEmail : undefined,
    guestIsAnonymous: typeof body.guestIsAnonymous === "boolean" ? body.guestIsAnonymous : undefined,
    body: body.body,
  };
}

export function parseUnlistedCreateCommentBody(body: CreateCommentRequestBody): ParsedCreateCommentInput {
  if (typeof body.body !== "string") {
    throw createError({ statusCode: 400, statusMessage: "无效请求" });
  }
  return {
    parentId: parseParentId(body.parentId),
    guestDisplayName: typeof body.guestDisplayName === "string" ? body.guestDisplayName : undefined,
    guestEmail: typeof body.guestEmail === "string" ? body.guestEmail : undefined,
    guestIsAnonymous: typeof body.guestIsAnonymous === "boolean" ? body.guestIsAnonymous : undefined,
    body: body.body,
  };
}

function parseParentId(rawParentId: unknown): number | null {
  if (rawParentId === undefined || rawParentId === null) {
    return null;
  }
  if (typeof rawParentId === "number" && Number.isFinite(rawParentId)) {
    return rawParentId;
  }
  throw createError({ statusCode: 400, statusMessage: "无效请求" });
}