#if UNITY_STANDALONE_WIN
using System;
using System.Runtime.InteropServices;


namespace VRM
{
    public static class FileDialogForWindows
    {
        #region GetOpenFileName
        [StructLayout(LayoutKind.Sequential, CharSet = CharSet.Auto)]
        public class OpenFileName
        {
            public int structSize = 0;
            public IntPtr dlgOwner = IntPtr.Zero;
            public IntPtr instance = IntPtr.Zero;
            public String filter = null;
            public String customFilter = null;
            public int maxCustFilter = 0;
            public int filterIndex = 0;
            public String file = null;
            public int maxFile = 0;
            public String fileTitle = null;
            public int maxFileTitle = 0;
            public String initialDir = null;
            public String title = null;
            public int flags = 0;
            public short fileOffset = 0;
            public short fileExtension = 0;
            public String defExt = null;
            public IntPtr custData = IntPtr.Zero;
            public IntPtr hook = IntPtr.Zero;
            public String templateName = null;
            public IntPtr reservedPtr = IntPtr.Zero;
            public int reservedInt = 0;
            public int flagsEx = 0;
        }
        [DllImport("Comdlg32.dll", SetLastError = true, ThrowOnUnmappableChar = true, CharSet = CharSet.Auto)]
        public static extern bool GetOpenFileName([In, Out] OpenFileName ofn);
        public static bool GetOpenFileName1([In, Out] OpenFileName ofn)
        {
            return GetOpenFileName(ofn);
        }
        static string Filter(params string[] filters)
        {
            return string.Join("\0", filters) + "\0";
        }
        public static string FileDialog(string title, string extension)
        {
            OpenFileName ofn = new OpenFileName();
            ofn.structSize = Marshal.SizeOf(ofn);
            ofn.filter = Filter("All Files", "*.*", extension, "*" + extension);
            ofn.filterIndex = 2;
            ofn.file = new string(new char[256]);
            ofn.maxFile = ofn.file.Length;
            ofn.fileTitle = new string(new char[64]);
            ofn.maxFileTitle = ofn.fileTitle.Length;
            ofn.initialDir = UnityEngine.Application.dataPath;
            ofn.title = title;
            ofn.defExt = "PNG";
            ofn.flags = 0x00080000 | 0x00001000 | 0x00000800 | 0x00000200 | 0x00000008;//OFN_EXPLORER|OFN_FILEMUSTEXIST|OFN_PATHMUSTEXIST| OFN_ALLOWMULTISELECT|OFN_NOCHANGEDIR
            if (!GetOpenFileName(ofn))
            {
                return null;
                //FileDialogResult("file:///" + ofn.file);
            }        // later, possibly in some other method:

            return ofn.file;

        }
        #endregion
#endif
    }
}