Audio Library Part I - (Windows Mixer Control)

//
//  THIS CODE AND INFORMATION IS PROVIDED "AS IS" WITHOUT WARRANTY OF ANY
//  KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE
//  IMPLIED WARRANTIES OF MERCHANTABILITY AND/OR FITNESS FOR A PARTICULAR
//  PURPOSE. IT CAN BE DISTRIBUTED FREE OF CHARGE AS LONG AS THIS HEADER 
//  REMAINS UNCHANGED.
//
//  Email:  gustavo_franco@hotmail.com
//
//  Copyright (C) 2005 Franco, Gustavo 
//
using System;
using System.Diagnostics;
using System.Runtime.InteropServices;

namespace WaveLib.AudioMixer
{
	#region Aliases
	using HMIXER	= System.IntPtr;
	using HWAVEIN	= System.IntPtr;
	using HWAVEOUT	= System.IntPtr;
	#endregion

	[Author("Gustavo Franco")]
	public class MixerLine
	{
		#region Variables Declaration
		private string					mName;
		private	Channel					mChannel;
		private uint					mChannels;
		private uint					mConnections;
		private uint					mCControls;
		private MIXERLINE_COMPONENTTYPE	mComponentType;
		private uint					mFlag;
		private uint 					mId;
		private uint					mSource;
		private uint					mDestination;
		private MixerType				mDirection;
		private IntPtr					mHMixer;
		private MixerControls			mControls = new MixerControls();
		private Mixer					mMixer;
		#endregion

		#region Constructors
		public MixerLine()
		{
			mName			= "";
			mComponentType	= (MIXERLINE_COMPONENTTYPE) (-1);
			mChannel		= Channel.Uniform;
			unchecked
			{
				mId			= (uint) -1;
			}
		}
		#endregion

		#region Properties
		#region Mixer
		public Mixer Mixer
		{
			get{return mMixer;}
			set{mMixer = value;}
		}
		#endregion

		#region HMixer
		internal unsafe IntPtr HMixer
		{
			get{return mHMixer;}
			set
			{
				MMErrors			errorCode	= 0;
				MIXERLINECONTROLS   mlc			= new MIXERLINECONTROLS();
                IntPtr              pmc         = IntPtr.Zero;

				try
				{
					mHMixer = value;
					mControls.Clear();

					if (mCControls == 0)
						return;

					pmc				= Marshal.AllocHGlobal((int) (Marshal.SizeOf(typeof(MIXERCONTROL)) * mCControls));
					mlc.cbStruct    = (uint) sizeof(MIXERLINECONTROLS);
					mlc.dwLineID    = mId;
					mlc.cControls   = mCControls;
					mlc.pamxctrl    = pmc;
					mlc.cbmxctrl    = (uint) (Marshal.SizeOf(typeof(MIXERCONTROL)));

					errorCode = (MMErrors) MixerNative.mixerGetLineControls(mHMixer, ref mlc, MIXER_GETLINECONTROLSFLAG.ALL);
					if (errorCode != MMErrors.MMSYSERR_NOERROR)
						throw new MixerException(errorCode, Mixers.GetErrorDescription(FuncName.fnMixerGetLineControls, errorCode));

					for(int i=0; i<mlc.cControls; i++)
					{
						MIXERCONTROL mc = (MIXERCONTROL) Marshal.PtrToStructure((IntPtr) (((byte*)pmc) + (Marshal.SizeOf(typeof(MIXERCONTROL)) * i)), typeof(MIXERCONTROL));

						MixerControl mixerControl	= new MixerControl();
						mixerControl.Id				= mc.dwControlID;
						mixerControl.Type			= (MIXERCONTROL_CONTROLTYPE) mc.dwControlType;
						mixerControl.ControlFlag	= (MIXERCONTROL_CONTROLFLAG) mc.fdwControl;
						mixerControl.MultipleItems	= mc.cMultipleItems;
						mixerControl.Name			= mc.szName;
						mixerControl.Minimum		= mc.Bounds.dwMinimum;
						mixerControl.Maximum		= mc.Bounds.dwMaximum;
						mixerControl.Steps			= mc.Metrics.cSteps;
						mixerControl.Line			= this;
						mixerControl.HMixer			= mHMixer;

						mControls.Add(mixerControl);
					}
				}
				finally
				{
					if (pmc != IntPtr.Zero)
						Marshal.FreeHGlobal((IntPtr) pmc);
				}
			}
		}
		#endregion

		#region MixerControls
		public MixerControls Controls 
		{
			get{return mControls;}
			set{mControls = value;}
		}
		#endregion

		#region Flag
		internal uint Flag
		{
			get{return mFlag;}
			set{mFlag = value;}
		}
		#endregion

		#region Active
		public bool Active
		{
			get{return ((mFlag & (uint) MIXERLINE_LINEFLAG.ACTIVE) > 0);}
		}
		#endregion

		#region Connected
		public bool Connected
		{
			get{return ((mFlag & (uint) MIXERLINE_LINEFLAG.DISCONNECTED) == 0);}
		}
		#endregion

		#region IsSource
		public bool IsSource
		{
			get{return ((mFlag & (uint) MIXERLINE_LINEFLAG.SOURCE) > 0);}
		}
		#endregion

		#region Channels
		public uint Channels
		{
			get{return mChannels;}
			set{mChannels = value;}
		}
		#endregion

		#region CControls
		internal uint CControls
		{
			get{return mCControls;}
			set{mCControls = value;}
		}
		#endregion

		#region Connections
		public uint Connections
		{
			get{return mConnections;}
			set{mConnections = value;}
		}
		#endregion

		#region Direction
		public MixerType Direction 
		{
			get{return mDirection;}
			set{mDirection = value;}
		}
		#endregion

		#region Name
		public string Name
		{
			get{return mName;}
			set{mName = value;}
		}
		#endregion

		#region Soruce
		public uint	Source
		{
			get{return mSource;}
			set{mSource = value;}
		}
		#endregion

		#region Destination
		public uint Destination
		{
			get{return mDestination;}
			set{mDestination = value;}
		}
		#endregion

		#region ComponentType
		public MIXERLINE_COMPONENTTYPE ComponentType
		{
			get{return mComponentType;}
			set{mComponentType = value;}
		}
		#endregion

		#region Id
		public uint Id
		{
			get{return mId;}
			set{mId = value;}
		}
		#endregion

		#region Children Properties
		#region Channel
		public Channel Channel
		{
			get{return mChannel;}
			set{mChannel = value;}
		}
		#endregion

		#region Volume
		public int Volume
		{
			get
			{
				MixerControl mixerControl = Controls.GetControlByType(MIXERCONTROL_CONTROLTYPE.VOLUME);
				if (mixerControl == null)
					return -1;
				else
					return (int) mixerControl.Volume;
			}
			set
			{
				MixerControl mixerControl = Controls.GetControlByType(MIXERCONTROL_CONTROLTYPE.VOLUME);
				if (mixerControl != null)
					mixerControl.Volume = value;
			}
		}

		public int VolumeMax
		{
			get
			{
				MixerControl mixerControl = Controls.GetControlByType(MIXERCONTROL_CONTROLTYPE.VOLUME);
				if (mixerControl == null)
					return -1;
				else
					return (int) mixerControl.Maximum;
			}
		}

		public int VolumeMin
		{
			get
			{
				MixerControl mixerControl = Controls.GetControlByType(MIXERCONTROL_CONTROLTYPE.VOLUME);
				if (mixerControl == null)
					return -1;
				else
					return (int) mixerControl.Minimum;
			}
		}

		public bool ContainsVolume
		{
			get
			{
				MixerControl mixerControl = Controls.GetControlByType(MIXERCONTROL_CONTROLTYPE.VOLUME);
				if (mixerControl == null)
					return false;
				return true;
			}
		}
		#endregion

		#region Mute
		public bool Mute
		{
			get
			{
				MixerControl mixerControl = Controls.GetControlByType(MIXERCONTROL_CONTROLTYPE.MUTE);
				if (mixerControl == null)
					return false;
				else
					return mixerControl.Mute;
			}
			set
			{
				MixerControl mixerControl = Controls.GetControlByType(MIXERCONTROL_CONTROLTYPE.MUTE);
				if (mixerControl != null)
					mixerControl.Mute = value;
			}
		}

		public bool ContainsMute
		{
			get
			{
				MixerControl mixerControl = Controls.GetControlByType(MIXERCONTROL_CONTROLTYPE.MUTE);
				if (mixerControl == null)
					return false;
				return true;
			}
		}
		#endregion

		#region Selected
		public bool Selected
		{
			get
			{
				if (this.Direction == MixerType.Playback)
					return false;

				MixerLine lineMux = this.Mixer.Lines.GetMixerFirstLineByComponentType(MIXERLINE_COMPONENTTYPE.DST_WAVEIN);
				if (lineMux == null || lineMux.IsSource)
					return false;

				MixerControls controls = lineMux.Controls;
				MixerControl muxControl = controls.GetControlByType(MIXERCONTROL_CONTROLTYPE.MUX);
				if (muxControl == null)
					return false;

				if (muxControl.Selected == Id)
					return true;

				return false;
			}
			set
			{
				if (this.Direction == MixerType.Playback)
					return;

				MixerLine lineMux = this.Mixer.Lines.GetMixerFirstLineByComponentType(MIXERLINE_COMPONENTTYPE.DST_WAVEIN);
				if (lineMux == null || lineMux.IsSource)
					return;

				MixerControls controls = lineMux.Controls;
				MixerControl muxControl = controls.GetControlByType(MIXERCONTROL_CONTROLTYPE.MUX);
				if (muxControl == null)
					return;

				if (value)
					muxControl.Selected = Id;
				else
					unchecked{muxControl.Selected = (uint) -1;}
			}
		}

		public bool ContainsSelected
		{
			get
			{
				if (this.Direction == MixerType.Playback)
					return false;

				MixerLine lineMux = this.Mixer.Lines.GetMixerFirstLineByComponentType(MIXERLINE_COMPONENTTYPE.DST_WAVEIN);
				if (lineMux == null || lineMux.IsSource)
					return false;

				MixerControls controls = lineMux.Controls;
				if (controls.GetControlByType(MIXERCONTROL_CONTROLTYPE.MUX) != null)
					return true;
				return false;
			}
		}
		#endregion

		#endregion
		#endregion

		#region Overrides
		public override string ToString()
		{
			return mName;
		}
		#endregion
	}
}