import StateChangeKind from "./StateChangeKind";
/**
 * Tracks the current value and modification state of a cached actor state item.
 *
 * The actor state manager uses StateMetadata to maintain a local cache of state
 * during an actor method invocation. Each state item tracks both its current value
 * and the kind of modification that has been applied to it since it was loaded or
 * created.
 *
 * This metadata is transient—it is cleared at the beginning of each actor method
 * invocation and persisted at the end through the state provider.
 *
 * @typeParam T - The type of the state value.
 *
 * @internal Intended for use by ActorStateManager; not typically used directly by application code.
 */
export default class StateMetadata<T> {
    private value;
    private changeKind;
    /**
     * Constructs a StateMetadata instance.
     *
     * @param value - The current state value.
     * @param changeKind - The type of modification applied to this state ({@link StateChangeKind}).
     */
    constructor(value: T, changeKind: StateChangeKind);
    /**
     * Retrieves the current state value.
     *
     * @returns The state value.
     */
    getValue(): T;
    /**
     * Retrieves the modification kind for this state item.
     *
     * @returns The {@link StateChangeKind} indicating ADD, UPDATE, REMOVE, or NONE.
     */
    getChangeKind(): StateChangeKind;
    /**
     * Updates the state value.
     *
     * @param value - The new state value.
     */
    setValue(value: T): void;
    /**
     * Updates the modification kind for this state item.
     *
     * @param changeKind - The new {@link StateChangeKind}.
     */
    setChangeKind(changeKind: StateChangeKind): void;
}