//! \file       Shell.cs
//! \date       Tue Aug 02 13:48:55 2011
//! \brief      Win32 shell functions.
//
// Copyright (C) 2011 by poddav
//
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to
// deal in the Software without restriction, including without limitation the
// rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
// sell copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in
// all copies or substantial portions of the Software.
//
// 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.
//

using System;
using System.Text;
using System.Runtime.InteropServices;

namespace Rnd.Shell
{
    /// <summary>
    /// Wrapper around PathCreateFromUrl WINAPI call.
    /// </summary>
    class PathConverter
    {
        [DllImport("shlwapi.dll", EntryPoint="PathCreateFromUrlW", CharSet=CharSet.Unicode, SetLastError=true)]
        private static extern Int32 PathCreateFromUrl(
                string url, StringBuilder path,
                ref Int32 size, UInt32 flags);

        private StringBuilder   buf;
        private Int32           size;

        public PathConverter (int capacity = 260)
        {
            buf = new StringBuilder (capacity);
        }
        public string UrlToPath (string url)
        {
            size = buf.Capacity;
            Int32 rc = PathCreateFromUrl (url, buf, ref size, 0);
            return rc == 0 ? buf.ToString (0, size) : "";
        }
    }

    /// <summary>
    /// Wrapper around SHGetFileInfo WINAPI call.
    /// </summary>
    class FileInfo
    {
        [DllImport("shell32.dll", CharSet=CharSet.Auto)]
        public static extern IntPtr SHGetFileInfo(
                string pszPath, Int32 dwFileAttributes,
                ref SHFILEINFO psfi, int cbFileInfo, int uFlags);

        [DllImport("User32.dll")]
        public static extern int DestroyIcon(IntPtr hIcon);

        [StructLayout(LayoutKind.Sequential, CharSet=CharSet.Auto)]
        public struct SHFILEINFO
        {
             public IntPtr hIcon;
             public int iIcon;
             public uint dwAttributes;

             [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 260)]
             public string szDisplayName;

             [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 80)]
             public string szTypeName;

             public SHFILEINFO(bool b)
             {
                 hIcon = IntPtr.Zero;
                 iIcon = 0;
                 dwAttributes = 0;
                 szDisplayName = "";
                 szTypeName = "";
             }
        };

        [Flags]
        public enum SHGFI : uint
        {
            /// <summary>get icon</summary>
            Icon            = 0x000000100,  
            /// <summary>get display name</summary>
            DisplayName     = 0x000000200,
            /// <summary>get type name</summary>
            TypeName        = 0x000000400,
            /// <summary>get attributes</summary>
            Attributes      = 0x000000800,
            /// <summary>get icon location</summary>
            IconLocation    = 0x000001000,  
            /// <summary>return exe type</summary>
            ExeType         = 0x000002000,  
            /// <summary>get system icon index</summary>
            SysIconIndex    = 0x000004000,  
            /// <summary>put a link overlay on icon</summary>
            LinkOverlay     = 0x000008000,  
            /// <summary>show icon in selected state</summary>
            Selected        = 0x000010000,  
            /// <summary>get only specified attributes</summary>
            Attr_Specified  = 0x000020000,  
            /// <summary>get large icon</summary>
            LargeIcon       = 0x000000000,  
            /// <summary>get small icon</summary>
            SmallIcon       = 0x000000001,  
            /// <summary>get open icon</summary>
            OpenIcon        = 0x000000002,  
            /// <summary>get shell size icon</summary>
            ShellIconSize   = 0x000000004,  
            /// <summary>pszPath is a pidl</summary>
            PIDL            = 0x000000008,  
            /// <summary>use passed dwFileAttribute</summary>
            UseFileAttributes= 0x000000010,  
            /// <summary>apply the appropriate overlays</summary>
            AddOverlays     = 0x000000020,  
            /// <summary>Get the index of the overlay in the upper 8 bits of the iIcon</summary>
            OverlayIndex    = 0x000000040,  
        }

        public static string GetTypeName (string filename)
        {
            SHFILEINFO info = new SHFILEINFO(true);
            int szInfo = Marshal.SizeOf (info);
            int result = (int)SHGetFileInfo (filename, 0, ref info, szInfo, (int)SHGFI.TypeName);

            // If uFlags does not contain SHGFI_EXETYPE or SHGFI_SYSICONINDEX,
            // the return value is nonzero if successful, or zero otherwise.
            if (result != 0)
                return info.szTypeName;
            else
                return string.Empty;
        }

        public static SHFILEINFO? GetInfo (string filename, SHGFI flags)
        {
            SHFILEINFO info = new SHFILEINFO(true);
            int szInfo = Marshal.SizeOf (info);
            int result = (int)SHGetFileInfo (filename, 0, ref info, szInfo, (int)flags);

            return result != 0? new Nullable<SHFILEINFO> (info): null;
        }
    }

    /// <summary>
    /// Wrapper around MoveFileEx WINAPI call.
    /// </summary>
    class File
    {
        [DllImport("kernel32.dll", EntryPoint="MoveFileExW", SetLastError=true, CharSet=CharSet.Unicode)]
        public static extern bool MoveFileEx (string lpExistingFileName, string lpNewFileName, MoveFileFlags dwFlags);

        [Flags]
        public enum MoveFileFlags : uint
        {
            ReplaceExisting         = 0x00000001,
            CopyAllowed             = 0x00000002,
            DelayUntilReboot        = 0x00000004,
            WriteThrough            = 0x00000008,
            CreateHardlink          = 0x00000010,
            FailIfNotTrackable      = 0x00000020
        }

        public static bool Rename (string szFrom, string szTo)
        {
            return MoveFileEx (szFrom, szTo, MoveFileFlags.ReplaceExisting);
        }
    }
}