import type { ZodError } from "zod";

/** Result shape shared by all admin form actions (via useActionState). */
export type FormState = {
  status?: "success";
  /** Form-level message not tied to a single field. */
  formError?: string;
  /** Per-field messages, keyed by input name. */
  fieldErrors?: Record<string, string[]>;
};

export const initialFormState: FormState = {};

export function zodErrorToFormState(error: ZodError): FormState {
  const fieldErrors: Record<string, string[]> = {};
  for (const issue of error.issues) {
    const key = issue.path.length > 0 ? String(issue.path[0]) : "_form";
    (fieldErrors[key] ??= []).push(issue.message);
  }
  return { fieldErrors };
}

export function firstFieldError(
  state: FormState | undefined,
  field: string,
): string | undefined {
  return state?.fieldErrors?.[field]?.[0];
}