lmxopcua/src/ZB.MOM.WW.OtOpcUa.Host/Domain/Quality.cs

namespace ZB.MOM.WW.OtOpcUa.Host.Domain
{
    /// <summary>
    ///     OPC DA quality codes mapped from MXAccess quality values. (MXA-009, OPC-005)
    /// </summary>
    public enum Quality : byte
    {
        // Bad family (0-63)
        /// <summary>
        ///     No valid process value is available.
        /// </summary>
        Bad = 0,

        /// <summary>
        ///     The value is invalid because the Galaxy attribute definition or mapping is wrong.
        /// </summary>
        BadConfigError = 4,

        /// <summary>
        ///     The bridge is not currently connected to the Galaxy runtime.
        /// </summary>
        BadNotConnected = 8,

        /// <summary>
        ///     The runtime device or adapter failed while obtaining the value.
        /// </summary>
        BadDeviceFailure = 12,

        /// <summary>
        ///     The underlying field source reported a bad sensor condition.
        /// </summary>
        BadSensorFailure = 16,

        /// <summary>
        ///     Communication with the runtime failed while retrieving the value.
        /// </summary>
        BadCommFailure = 20,

        /// <summary>
        ///     The attribute is intentionally unavailable for service, such as a locked or unwritable value.
        /// </summary>
        BadOutOfService = 24,

        /// <summary>
        ///     The bridge is still waiting for the first usable value after startup or resubscription.
        /// </summary>
        BadWaitingForInitialData = 32,

        // Uncertain family (64-191)
        /// <summary>
        ///     A value is available, but it should be treated cautiously.
        /// </summary>
        Uncertain = 64,

        /// <summary>
        ///     The last usable value is being repeated because a newer one is unavailable.
        /// </summary>
        UncertainLastUsable = 68,

        /// <summary>
        ///     The sensor or source is providing a value with reduced accuracy.
        /// </summary>
        UncertainSensorNotAccurate = 80,

        /// <summary>
        ///     The value exceeds its engineered limits.
        /// </summary>
        UncertainEuExceeded = 84,

        /// <summary>
        ///     The source is operating in a degraded or subnormal state.
        /// </summary>
        UncertainSubNormal = 88,

        // Good family (192+)
        /// <summary>
        ///     The value is current and suitable for normal client use.
        /// </summary>
        Good = 192,

        /// <summary>
        ///     The value is good but currently overridden locally rather than flowing from the live source.
        /// </summary>
        GoodLocalOverride = 216
    }

    /// <summary>
    ///     Helper methods for reasoning about OPC quality families used by the bridge.
    /// </summary>
    public static class QualityExtensions
    {
        /// <summary>
        ///     Determines whether the quality represents a good runtime value that can be trusted by OPC UA clients.
        /// </summary>
        /// <param name="q">The quality code to inspect.</param>
        /// <returns><see langword="true" /> when the value is in the good quality range; otherwise, <see langword="false" />.</returns>
        public static bool IsGood(this Quality q)
        {
            return (byte)q >= 192;
        }

        /// <summary>
        ///     Determines whether the quality represents an uncertain runtime value that should be treated cautiously.
        /// </summary>
        /// <param name="q">The quality code to inspect.</param>
        /// <returns><see langword="true" /> when the value is in the uncertain range; otherwise, <see langword="false" />.</returns>
        public static bool IsUncertain(this Quality q)
        {
            return (byte)q >= 64 && (byte)q < 192;
        }

        /// <summary>
        ///     Determines whether the quality represents a bad runtime value that should not be used as valid process data.
        /// </summary>
        /// <param name="q">The quality code to inspect.</param>
        /// <returns><see langword="true" /> when the value is in the bad range; otherwise, <see langword="false" />.</returns>
        public static bool IsBad(this Quality q)
        {
            return (byte)q < 64;
        }
    }
}