SystemTrayMenu/UserInterface/Dialogs/FolderDialog.cs

// <copyright file="FolderDialog.cs" company="PlaceholderCompany">
// Copyright (c) PlaceholderCompany. All rights reserved.
// </copyright>

namespace SystemTrayMenu.UserInterface.Dialogs
{
    using System;
    using System.IO;
    using System.Runtime.CompilerServices;
    using System.Runtime.InteropServices;
    using System.Windows.Forms;
    using SystemTrayMenu.Utilities;

    public class FolderDialog : IFolderDialog, IDisposable
    {
        private bool isDisposed;

        /// <summary>
        /// Gets or sets /sets folder in which dialog will be open.
        /// </summary>
        public string InitialFolder { get; set; }

        /// <summary>
        /// Gets or sets /sets directory in which dialog will be open
        /// if there is no recent directory available.
        /// </summary>
        public string DefaultFolder { get; set; }

        /// <summary>
        /// Gets or sets selected folder.
        /// </summary>
        public string Folder { get; set; }

        public DialogResult ShowDialog()
        {
            return ShowDialog(owner: new WindowWrapper(IntPtr.Zero));
        }

        public DialogResult ShowDialog(IWin32Window owner)
        {
            if (Environment.OSVersion.Version.Major >= 6)
            {
                return ShowVistaDialog(owner);
            }
            else
            {
                return ShowLegacyDialog(owner);
            }
        }

        public DialogResult ShowVistaDialog(IWin32Window owner)
        {
            NativeMethods.IFileDialog frm = (NativeMethods.IFileDialog)new NativeMethods.FileOpenDialogRCW();
            frm.GetOptions(out uint options);
            options |= NativeMethods.FOS_PICKFOLDERS |
                       NativeMethods.FOS_FORCEFILESYSTEM |
                       NativeMethods.FOS_NOVALIDATE |
                       NativeMethods.FOS_NOTESTFILECREATE |
                       NativeMethods.FOS_DONTADDTORECENT;
            frm.SetOptions(options);
            if (InitialFolder != null)
            {
                Guid riid = new Guid("43826D1E-E718-42EE-BC55-A1E261C37BFE"); // IShellItem
                if (NativeMethods.SHCreateItemFromParsingName(
                    InitialFolder,
                    IntPtr.Zero,
                    ref riid,
                    out NativeMethods.IShellItem directoryShellItem) == NativeMethods.S_OK)
                {
                    frm.SetFolder(directoryShellItem);
                }
            }

            if (DefaultFolder != null)
            {
                Guid riid = new Guid("43826D1E-E718-42EE-BC55-A1E261C37BFE"); // IShellItem
                if (NativeMethods.SHCreateItemFromParsingName(
                    DefaultFolder,
                    IntPtr.Zero,
                    ref riid,
                    out NativeMethods.IShellItem directoryShellItem) == NativeMethods.S_OK)
                {
                    frm.SetDefaultFolder(directoryShellItem);
                }
            }

            if (owner != null && frm.Show(owner.Handle) == NativeMethods.S_OK)
            {
                if (frm.GetResult(out NativeMethods.IShellItem shellItem) == NativeMethods.S_OK)
                {
                    if (shellItem.GetDisplayName(
                        NativeMethods.SIGDN_FILESYSPATH,
                        out IntPtr pszString) == NativeMethods.S_OK)
                    {
                        if (pszString != IntPtr.Zero)
                        {
                            try
                            {
                                Folder = Marshal.PtrToStringAuto(pszString);
                                return DialogResult.OK;
                            }
                            finally
                            {
                                Marshal.FreeCoTaskMem(pszString);
                            }
                        }
                    }
                }
            }

            return DialogResult.Cancel;
        }

        public DialogResult ShowLegacyDialog(IWin32Window owner)
        {
            using SaveFileDialog frm = new SaveFileDialog
            {
                CheckFileExists = false,
                CheckPathExists = true,
                CreatePrompt = false,
                Filter = "|" + Guid.Empty.ToString(),
                FileName = "any",
            };
            if (InitialFolder != null)
            {
                frm.InitialDirectory = InitialFolder;
            }

            frm.OverwritePrompt = false;
            frm.Title = Translator.GetText("Select Folder");
            frm.ValidateNames = false;
            if (frm.ShowDialog(owner) == DialogResult.OK)
            {
                Folder = Path.GetDirectoryName(frm.FileName);
                return DialogResult.OK;
            }
            else
            {
                return DialogResult.Cancel;
            }
        }

        public void Dispose()
        {
            Dispose(true);
            GC.SuppressFinalize(this);
        }

        protected virtual void Dispose(bool disposing)
        {
            if (!isDisposed)
            {
            }

            isDisposed = true;
        }
    }

    public class WindowWrapper : System.Windows.Forms.IWin32Window
    {
        /// <summary>
        /// Initializes a new instance of the <see cref="WindowWrapper"/> class.
        /// </summary>
        /// <param name="handle">Handle to wrap.</param>
        public WindowWrapper(IntPtr handle)
        {
            hwnd = handle;
        }

        /// <summary>
        /// Gets original ptr.
        /// </summary>
        public IntPtr Handle => hwnd;

        private readonly IntPtr hwnd;
    }

    internal static class NativeMethods
    {
        public const uint FOS_PICKFOLDERS = 0x00000020;
        public const uint FOS_FORCEFILESYSTEM = 0x00000040;
        public const uint FOS_NOVALIDATE = 0x00000100;
        public const uint FOS_NOTESTFILECREATE = 0x00010000;
        public const uint FOS_DONTADDTORECENT = 0x02000000;

        public const uint S_OK = 0x0000;

        public const uint SIGDN_FILESYSPATH = 0x80058000;

        [ComImport]
        [ClassInterface(ClassInterfaceType.None)]
        [TypeLibType(TypeLibTypeFlags.FCanCreate)]
        [Guid("DC1C5A9C-E88A-4DDE-A5A1-60F82A20AEF7")]
        internal class FileOpenDialogRCW
        {
        }

        [ComImport]
        [Guid("42F85136-DB7E-439C-85F1-E4075D135FC8")]
        [InterfaceType(ComInterfaceType.InterfaceIsIUnknown)]
        internal interface IFileDialog
        {
            [MethodImpl(MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime)]
            [PreserveSig]
            uint Show([In, Optional] IntPtr hwndOwner);

            [MethodImpl(MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime)]
            uint SetFileTypes([In] uint cFileTypes, [In, MarshalAs(UnmanagedType.LPArray)] IntPtr rgFilterSpec);

            [MethodImpl(MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime)]
            uint SetFileTypeIndex([In] uint iFileType);

            [MethodImpl(MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime)]
            uint GetFileTypeIndex(out uint piFileType);

            [MethodImpl(MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime)]
            uint Advise(
            [In, MarshalAs(UnmanagedType.Interface)] IntPtr pfde,
            out uint pdwCookie);

            [MethodImpl(MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime)]
            uint Unadvise([In] uint dwCookie);

            [MethodImpl(MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime)]
            uint SetOptions([In] uint fos);

            [MethodImpl(MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime)]
            uint GetOptions(out uint fos);

            [MethodImpl(MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime)]
            void SetDefaultFolder([In, MarshalAs(UnmanagedType.Interface)] IShellItem psi);

            [MethodImpl(MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime)]
            uint SetFolder([In, MarshalAs(UnmanagedType.Interface)] IShellItem psi);

            [MethodImpl(MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime)]
            uint GetFolder([MarshalAs(UnmanagedType.Interface)] out IShellItem ppsi);

            [MethodImpl(MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime)]
            uint GetCurrentSelection([MarshalAs(UnmanagedType.Interface)] out IShellItem ppsi);

            [MethodImpl(MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime)]
            uint SetFileName([In, MarshalAs(UnmanagedType.LPWStr)] string pszName);

            [MethodImpl(MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime)]
            uint GetFileName([MarshalAs(UnmanagedType.LPWStr)] out string pszName);

            [MethodImpl(MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime)]
            uint SetTitle([In, MarshalAs(UnmanagedType.LPWStr)] string pszTitle);

            [MethodImpl(MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime)]
            uint SetOkButtonLabel([In, MarshalAs(UnmanagedType.LPWStr)] string pszText);

            [MethodImpl(MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime)]
            uint SetFileNameLabel([In, MarshalAs(UnmanagedType.LPWStr)] string pszLabel);

            [MethodImpl(MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime)]
            uint GetResult([MarshalAs(UnmanagedType.Interface)] out IShellItem ppsi);

            [MethodImpl(MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime)]
            uint AddPlace([In, MarshalAs(UnmanagedType.Interface)] IShellItem psi, uint fdap);

            [MethodImpl(MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime)]
            uint SetDefaultExtension([In, MarshalAs(UnmanagedType.LPWStr)]
                                     string pszDefaultExtension);

            [MethodImpl(MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime)]
            uint Close([MarshalAs(UnmanagedType.Error)] uint hr);

            [MethodImpl(MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime)]
            uint SetClientGuid([In] ref Guid guid);

            [MethodImpl(MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime)]
            uint ClearClientData();

            [MethodImpl(MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime)]
            uint SetFilter([MarshalAs(UnmanagedType.Interface)] IntPtr pFilter);
        }

        [ComImport]
        [Guid("43826D1E-E718-42EE-BC55-A1E261C37BFE")]
        [InterfaceType(ComInterfaceType.InterfaceIsIUnknown)]
        internal interface IShellItem
        {
            [MethodImpl(MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime)]
            uint BindToHandler(
                [In] IntPtr pbc,
                [In] ref Guid rbhid,
                [In] ref Guid riid,
                [Out, MarshalAs(UnmanagedType.Interface)] out IntPtr ppvOut);

            [MethodImpl(MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime)]
            uint GetParent([MarshalAs(UnmanagedType.Interface)] out IShellItem ppsi);

            [MethodImpl(MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime)]
            uint GetDisplayName([In] uint sigdnName, out IntPtr ppszName);

            [MethodImpl(MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime)]
            uint GetAttributes([In] uint sfgaoMask, out uint psfgaoAttribs);

            [MethodImpl(MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime)]
            uint Compare([In, MarshalAs(UnmanagedType.Interface)] IShellItem psi, [In] uint hint, out int piOrder);
        }

        [DllImport("shell32.dll", CharSet = CharSet.Unicode, SetLastError = true)]
        internal static extern int SHCreateItemFromParsingName(
            [MarshalAs(UnmanagedType.LPWStr)] string pszPath,
            IntPtr pbc,
            ref Guid riid,
            [MarshalAs(UnmanagedType.Interface)] out IShellItem ppv);
    }
}