ln.skyscanner/checks/SkyCheckState.cs

// /**
//  * File: SkyCheckState.cs
//  * Author: haraldwolff
//  *
//  * This file and it's content is copyrighted by the Author and / or copyright holder.
//  * Any use wihtout proper permission is illegal and may lead to legal actions.
//  *
//  *
//  **/
using System;
using ln.skyscanner.entities;
using ln.types.odb;
using Newtonsoft.Json;
using Newtonsoft.Json.Converters;
using System.Linq;
using ln.types.odb.attributes;
using System.Collections.Generic;
namespace ln.skyscanner.checks
{
    [JsonConverter(typeof(StringEnumConverter))]
    public enum CheckState { OK, WARN, CRITICAL, FAIL, ERROR }

    public struct CheckStateChange
    {
        public CheckState NewState;
        public DateTime Timestamp;

        public CheckStateChange(CheckState checkState)
        {
            NewState = checkState;
            Timestamp = DateTime.Now;
        }
    }

    public class SkyCheckState
    {
        [DocumentID]
        public Guid ID = Guid.NewGuid();

        public readonly String CheckName;
        [ByReference]
        public readonly Node Node;

        public String[] PerformanceValues => performanceValues.ToArray(); 
        List<String> performanceValues = new List<String>();

        public DateTime LastCheckTime { get; set; }

        public double WarnLower { get; set; } = Double.MinValue;
        public double WarnUpper { get; set; } = Double.MaxValue;
        public double CritLower { get; set; } = Double.MinValue;
        public double CritUpper { get; set; } = Double.MaxValue;

        public CheckState CheckState { get => currentCheckState; set { if (currentCheckState != value) history.Add(new CheckStateChange(value)); currentCheckState = value; } }
        CheckState currentCheckState;

        public CheckStateChange[] History => history.ToArray();
        List<CheckStateChange> history = new List<CheckStateChange>();

        protected SkyCheckState()
        {
        }
        public SkyCheckState(SkyCheck skyCheck,Node node)
        {
            CheckName = skyCheck.Name;
            Node = node;
        }

        public void EnsurePerformanceValue(String perfName)
        {
            if (performanceValues == null)
                performanceValues = new List<string>();

            if (!performanceValues.Contains(perfName))
                performanceValues.Add(perfName);
        }


        public class PerformanceValue
        {

        }

    }
}