namespace ZB.MOM.WW.OtOpcUa.Server.Alarms;

/// <summary>
///     Lifecycle transition for an alarm condition. Mirrors OPC UA Part 9 alarm states
///     simplified to the active / acknowledged / inactive triplet that every driver in
///     the repo exposes today.
/// </summary>
public enum AlarmStateTransition
{
    /// <summary>InAlarm flipped false → true. Default to unacknowledged.</summary>
    Active,

    /// <summary>Acked flipped false → true while the alarm is still active.</summary>
    Acknowledged,

    /// <summary>InAlarm flipped true → false.</summary>
    Inactive,
}

/// <summary>
///     One alarm-state transition raised by <see cref="AlarmConditionService.TransitionRaised"/>.
/// </summary>
/// <param name="ConditionId">Stable identifier the caller registered the condition under (typically the driver's alarm full reference).</param>
/// <param name="Transition">Which state the alarm transitioned to.</param>
/// <param name="Priority">Latest known priority. 0 when no priority sub-attribute was registered or no value has been observed yet.</param>
/// <param name="Description">Latest known description text; null when not registered or not yet observed.</param>
/// <param name="AtUtc">Server-clock UTC of the value change that produced this transition.</param>
public sealed record AlarmConditionTransition(
    string ConditionId,
    AlarmStateTransition Transition,
    int Priority,
    string? Description,
    DateTime AtUtc);

/// <summary>
///     Read-only snapshot of an alarm condition's current state. Used for diagnostics
///     and dashboards; not part of the live transition stream.
/// </summary>
public sealed record AlarmConditionSnapshot(
    string ConditionId,
    bool InAlarm,
    bool Acked,
    int Priority,
    string? Description);