/**
 * Toolkit - Type Helpers
 *
 * TypeScript utility types and helper functions.
 */

/**
 * Make specific properties optional
 */
export type PartialBy<T, K extends keyof T> = Omit<T, K> & Partial<Pick<T, K>>;

/**
 * Make specific properties required
 */
export type RequiredBy<T, K extends keyof T> = Omit<T, K> & Required<Pick<T, K>>;

/**
 * Deep partial (makes all nested properties optional)
 */
export type DeepPartial<T> = T extends object ? { [P in keyof T]?: DeepPartial<T[P]> } : T;

/**
 * Extract keys of a certain type
 */
export type KeysOfType<T, U> = {
  [K in keyof T]: T[K] extends U ? K : never;
}[keyof T];

/**
 * Pick properties by value type
 */
export type PickByValue<T, V> = Pick<
  T,
  {
    [K in keyof T]: T[K] extends V ? K : never;
  }[keyof T]
>;