/*

   This Source Code Form is subject to the terms of the Mozilla Public

   License, v. 2.0. If a copy of the MPL was not distributed with this

   file, You can obtain one at http://mozilla.org/MPL/2.0/.

   Copyright (C) 2009-2010 Paul Werelds <paul@werelds.net>

 	Copyright (C) 2012 Michael Möller <mmoeller@openhardwaremonitor.org>

 */

 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.WMI {

   /// <summary>

   /// The WMI Provider.

   /// This class is not exposed to WMI itself.

   /// </summary>

   public class WmiProvider : IDisposable {

     private List<IWmiObject> activeInstances;

     public WmiProvider(IComputer computer) {

       activeInstances = new List<IWmiObject>();

       foreach (IHardware hardware in computer.Hardware)

         ComputerHardwareAdded(hardware);

       computer.HardwareAdded += ComputerHardwareAdded;

       computer.HardwareRemoved += ComputerHardwareRemoved;

     }

     public void Update() {

       foreach (IWmiObject 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);

         try {

           Instrumentation.Publish(hw);

         } catch (Exception) { }

       }

       foreach (IHardware subHardware in hardware.SubHardware)

         ComputerHardwareAdded(subHardware);

     }

     private void HardwareSensorAdded(ISensor data) {

       Sensor sensor = new Sensor(data);

       activeInstances.Add(sensor);

       try {

         Instrumentation.Publish(sensor);

       } catch (Exception) { }

     }

     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()

       );

       if (instanceIndex == -1)

         return;

       try {

         Instrumentation.Revoke(activeInstances[instanceIndex]);

       } catch (Exception) { }

       activeInstances.RemoveAt(instanceIndex);

     }

     #endregion

     public void Dispose() {

       foreach (IWmiObject instance in activeInstances) {

         try {

           Instrumentation.Revoke(instance);

         } catch (Exception) { }

       }

       activeInstances = null;

     }

   }

 }