using System;

 using System.Collections.Generic;

 using System.Management.Instrumentation;

 using OpenHardwareMonitor.Hardware;

 [assembly: Instrumented("root/OpenHardwareMonitor")]

 [System.ComponentModel.RunInstaller(true)]

 public class InstanceInstaller : DefaultManagementProjectInstaller { }

 namespace OpenHardwareMonitor.WMIProvider {

   public class WmiProvider : IDisposable {

     private List<IWmiClass> _activeInstances;

     public WmiProvider(IComputer computer) {

       _activeInstances = new List<IWmiClass>();

       foreach (IHardware hardware in computer.Hardware)

         ComputerHardwareAdded(hardware);

       computer.HardwareAdded += ComputerHardwareAdded;

       computer.HardwareRemoved += ComputerHardwareRemoved;

     }

     public void Update() {

       foreach (IWmiClass instance in _activeInstances)

         instance.Update();

     }

     #region Eventhandlers

     private void ComputerHardwareAdded(IHardware hardware) {

       if (!Exists(hardware.Identifier.ToString())) {

         foreach (ISensor sensor in hardware.Sensors)

           HardwareSensorAdded(sensor);

         hardware.SensorAdded += HardwareSensorAdded;

         hardware.SensorRemoved += HardwareSensorRemoved;

         Hardware hw = new Hardware(hardware);

         _activeInstances.Add(hw);

         Instrumentation.Publish(hw);

       }

       foreach (IHardware subHardware in hardware.SubHardware)

         ComputerHardwareAdded(subHardware);

     }

     private void HardwareSensorAdded(ISensor data) {

       Sensor sensor = new Sensor(data);

       _activeInstances.Add(sensor);

       Instrumentation.Publish(sensor);

     }

     private void ComputerHardwareRemoved(IHardware hardware) {

       hardware.SensorAdded -= HardwareSensorAdded;

       hardware.SensorRemoved -= HardwareSensorRemoved;

       foreach (ISensor sensor in hardware.Sensors) 

         HardwareSensorRemoved(sensor);

       foreach (IHardware subHardware in hardware.SubHardware)

         ComputerHardwareRemoved(subHardware);

       RevokeInstance(hardware.Identifier.ToString());

     }

     private void HardwareSensorRemoved(ISensor sensor) {

       RevokeInstance(sensor.Identifier.ToString());

     }

     #endregion

     #region Helpers

     private bool Exists(string identifier) {

       return _activeInstances.Exists(h => h.Identifier == identifier);

     }

     private void RevokeInstance(string identifier) {

       int instanceIndex = _activeInstances.FindIndex(

         item => item.Identifier == identifier.ToString()

       );

       Instrumentation.Revoke(_activeInstances[instanceIndex]);

       _activeInstances.RemoveAt(instanceIndex);

     }

     #endregion

     public void Dispose() {

       foreach (IWmiClass instance in _activeInstances)

         Instrumentation.Revoke(instance);

       _activeInstances = null;

     }

   }

 }