// -----------------------------------------
// SoundScribe (TM) and related software.
// 
// Copyright (C) 2007-2011 Vannatech
// http://www.vannatech.com
// All rights reserved.
// 
// This source code is subject to the MIT License.
// http://www.opensource.org/licenses/mit-license.php
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
// THE SOFTWARE.
// -----------------------------------------
// milligan22963 - ported to nAudio
// -----------------------------------------

using System;
using System.Runtime.InteropServices;

namespace NAudio.CoreAudioApi.Interfaces
{
    /// <summary>
    /// Windows CoreAudio ISimpleAudioVolume interface
    /// Defined in AudioClient.h
    /// </summary>
    [Guid("87CE5498-68D6-44E5-9215-6DA47EF883D8"),
        InterfaceType(ComInterfaceType.InterfaceIsIUnknown),
        ComImport]
    internal interface ISimpleAudioVolume
    {
        /// <summary>
        /// Sets the master volume level for the audio session.
        /// </summary>
        /// <param name="levelNorm">The new volume level expressed as a normalized value between 0.0 and 1.0.</param>
        /// <param name="eventContext">A user context value that is passed to the notification callback.</param>
        /// <returns>An HRESULT code indicating whether the operation succeeded of failed.</returns>
        [PreserveSig]
        int SetMasterVolume(
            [In] [MarshalAs(UnmanagedType.R4)] float levelNorm,
            [In] [MarshalAs(UnmanagedType.LPStruct)] Guid eventContext);

        /// <summary>
        /// Retrieves the client volume level for the audio session.
        /// </summary>
        /// <param name="levelNorm">Receives the volume level expressed as a normalized value between 0.0 and 1.0. </param>
        /// <returns>An HRESULT code indicating whether the operation succeeded of failed.</returns>
        [PreserveSig]
        int GetMasterVolume(
            [Out] [MarshalAs(UnmanagedType.R4)] out float levelNorm);

        /// <summary>
        /// Sets the muting state for the audio session.
        /// </summary>
        /// <param name="isMuted">The new muting state.</param>
        /// <param name="eventContext">A user context value that is passed to the notification callback.</param>
        /// <returns>An HRESULT code indicating whether the operation succeeded of failed.</returns>
        [PreserveSig]
        int SetMute(
            [In] [MarshalAs(UnmanagedType.Bool)] bool isMuted,
            [In] [MarshalAs(UnmanagedType.LPStruct)] Guid eventContext);

        /// <summary>
        /// Retrieves the current muting state for the audio session.
        /// </summary>
        /// <param name="isMuted">Receives the muting state.</param>
        /// <returns>An HRESULT code indicating whether the operation succeeded of failed.</returns>
        [PreserveSig]
        int GetMute(
            [Out] [MarshalAs(UnmanagedType.Bool)] out bool isMuted);
    }
}