using System;

using System.Collections.Concurrent;

using System.Collections.Generic;

using System.Linq;

using System.Security;

using System.Text;

using System.Web;

using Microsoft.Win32;

namespace SmartStore.Core.IO

{

public static class MimeTypes

{

private static readonly ConcurrentDictionary<string, string> _mimeMap = new ConcurrentDictionary<string, string>(StringComparer.OrdinalIgnoreCase);

public static string MapNameToMimeType(string fileNameOrExtension)

{

return MimeMapping.GetMimeMapping(fileNameOrExtension);

}

/// <summary>

/// Returns the (dotless) extension for a mime type

/// </summary>

/// <param name="mimeType">The mime type</param>

/// <returns>The corresponding file extension (without dot)</returns>

public static string MapMimeTypeToExtension(string mimeType)

{

if (mimeType.IsEmpty())

return null;

return _mimeMap.GetOrAdd(mimeType, k => {

string result = null;

try

{

using (var key = Registry.ClassesRoot.OpenSubKey(@"MIME\Database\Content Type\" + mimeType, false))

{

object value = key != null ? key.GetValue("Extension", null) : null;

result = value != null ? value.ToString().Trim('.') : null;

}

}

catch

{

string[] parts = mimeType.Split('/');

result = parts[parts.Length - 1];

switch (result)

{

case "pjpeg":

result = "jpg";

break;

case "x-png":

result = "png";

break;

case "x-icon":

result = "ico";

break;

}

}

return result;

});

}

}

}