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 * Copyright (C) 2026, Leo Galambos
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 *    This product includes software developed by the Egothor project.
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package zeroecho.pki.util.async;

/**
 * Lifecycle state of an asynchronous operation.
 *
 * <p>
 * The state machine is intentionally simple and audit-friendly. Implementations
 * may attach additional non-sensitive detail through
 * {@link AsyncStatus#detailCode()} and {@link AsyncStatus#details()}.
 * </p>
 */
public enum AsyncState {

    /**
     * The operation has been created and is awaiting processing.
     *
     * <p>
     * Example: a certificate issuance request has been accepted, but is waiting for
     * an operator approval step.
     * </p>
     */
    SUBMITTED,

    /**
     * The operation is currently being processed.
     *
     * <p>
     * Example: an issuance request is being built, proof-of-possession verified, or
     * a signing workflow is executing.
     * </p>
     */
    RUNNING,

    /**
     * The operation completed successfully and the result is available for
     * retrieval.
     *
     * <p>
     * Example: a certificate (or bundle) has been issued and is ready to be
     * fetched.
     * </p>
     */
    SUCCEEDED,

    /**
     * The operation completed unsuccessfully (terminal failure).
     *
     * <p>
     * Example: proof-of-possession verification failed or a policy rule rejected
     * the request. The failure reason should be exposed via a stable, non-secret
     * {@link AsyncStatus#detailCode()} and optional {@link AsyncStatus#details()}.
     * </p>
     */
    FAILED,

    /**
     * The operation was cancelled by a caller or operator.
     *
     * <p>
     * Example: an administrator cancelled a long-running operation before it was
     * approved.
     * </p>
     */
    CANCELLED,

    /**
     * The operation exceeded its declared deadline and was expired by the bus.
     *
     * <p>
     * Example: a request had a 24h approval window; after that it is no longer
     * eligible for completion and is treated as expired.
     * </p>
     */
    EXPIRED
}
