using System;
using System.Text;

namespace prBrowser
{
	internal static class URLUtils
	{
		private class UrlDecoder
		{
			private int _bufferSize;

			private byte[] _byteBuffer;

			private char[] _charBuffer;

			private Encoding _encoding;

			private int _numBytes;

			private int _numChars;

			public bool forFilePaths = false;

			internal UrlDecoder(int bufferSize, Encoding encoding)
			{
				_bufferSize = bufferSize;
				_encoding = encoding;
				_charBuffer = new char[bufferSize];
			}

			internal void AddByte(byte b)
			{
				if (_byteBuffer == null)
				{
					_byteBuffer = new byte[_bufferSize];
				}
				_byteBuffer[_numBytes++] = b;
			}

			internal void AddChar(char ch, bool checkChar = false)
			{
				if (_numBytes > 0)
				{
					FlushBytes();
				}
				if (checkChar && forFilePaths && !ch.SupportedInFilePath())
				{
					AddChar('_');
					int num = ch;
					AddString("0x" + num.ToString("X"));
					AddChar('_');
				}
				else
				{
					_charBuffer[_numChars++] = ch;
				}
			}

			internal void AddString(string str)
			{
				if (_numBytes > 0)
				{
					FlushBytes();
				}
				foreach (char ch in str)
				{
					_charBuffer[_numChars++] = ch;
				}
			}

			public void FlushBytes(bool checkChar = false)
			{
				if (_numBytes <= 0)
				{
					return;
				}
				if (checkChar && forFilePaths)
				{
					char[] newChars = _encoding.GetChars(_byteBuffer, 0, _numBytes);
					_numBytes = 0;
					char[] array = newChars;
					foreach (char ch in array)
					{
						AddChar(ch);
					}
				}
				else
				{
					_numChars += _encoding.GetChars(_byteBuffer, 0, _numBytes, _charBuffer, _numChars);
					_numBytes = 0;
				}
			}

			internal string GetString()
			{
				if (_numBytes > 0)
				{
					FlushBytes();
				}
				if (_numChars > 0)
				{
					return new string(_charBuffer, 0, _numChars);
				}
				return string.Empty;
			}
		}

		public static string PathToURL(this string filePath, string removeBaseDir = null)
		{
			if (!filePath.CheckIfValid())
			{
				return "";
			}
			return "file:///" + filePath.Replace("\\", "/");
		}

		public static bool IsURLOfflineFile(this string url)
		{
			return url.StartsWith("file://", StringComparison.Ordinal);
		}

		public static bool IsURLLocalhost(this string url)
		{
			return url.BeginsWith("http://localhost") || url.BeginsWith("localhost");
		}

		public static string DecodeURL(this string url)
		{
			if (url == null)
			{
				return null;
			}
			int length = url.Length;
			UrlDecoder decoder = new UrlDecoder(length, Encoding.UTF8);
			for (int i = 0; i < length; i++)
			{
				char ch = url[i];
				if (ch == '+')
				{
					ch = ' ';
				}
				else if (ch == '%' && i < length - 2)
				{
					if (url[i + 1] == 'u' && i < length - 5)
					{
						int num3 = url[i + 2].HexToInt();
						int num4 = url[i + 3].HexToInt();
						int num5 = url[i + 4].HexToInt();
						int num6 = url[i + 5].HexToInt();
						if (num3 >= 0 && num4 >= 0 && num5 >= 0 && num6 >= 0)
						{
							ch = (char)((num3 << 12) | (num4 << 8) | (num5 << 4) | num6);
							i += 5;
							decoder.AddChar(ch);
							continue;
						}
					}
					else
					{
						int num7 = url[i + 1].HexToInt();
						int num8 = url[i + 2].HexToInt();
						if (num7 >= 0 && num8 >= 0)
						{
							byte b = (byte)((num7 << 4) | num8);
							i += 2;
							decoder.AddByte(b);
							continue;
						}
					}
				}
				if ((ch & 0xFF80) == 0)
				{
					decoder.AddByte((byte)ch);
				}
				else
				{
					decoder.AddChar(ch);
				}
			}
			return decoder.GetString();
		}

		public static int HexToInt(this char hex)
		{
			if (hex >= '0' && hex <= '9')
			{
				return hex - 48;
			}
			if (hex >= 'a' && hex <= 'f')
			{
				return hex - 97 + 10;
			}
			if (hex >= 'A' && hex <= 'F')
			{
				return hex - 65 + 10;
			}
			return -1;
		}

		public static string DecodeURLForFilepath(this string url)
		{
			if (url == null)
			{
				return null;
			}
			int length = url.Length;
			UrlDecoder decoder = new UrlDecoder(length * 10, Encoding.UTF8);
			decoder.forFilePaths = true;
			for (int i = 0; i < length; i++)
			{
				char ch = url[i];
				if (ch == '+')
				{
					ch = ' ';
				}
				else if (ch == '%' && i < length - 2)
				{
					if (url[i + 1] == 'u' && i < length - 5)
					{
						int num3 = url[i + 2].HexToInt();
						int num4 = url[i + 3].HexToInt();
						int num5 = url[i + 4].HexToInt();
						int num6 = url[i + 5].HexToInt();
						if (num3 >= 0 && num4 >= 0 && num5 >= 0 && num6 >= 0)
						{
							ch = (char)((num3 << 12) | (num4 << 8) | (num5 << 4) | num6);
							i += 5;
							decoder.FlushBytes();
							decoder.AddChar(ch, checkChar: true);
							continue;
						}
					}
					else
					{
						int num7 = url[i + 1].HexToInt();
						int num8 = url[i + 2].HexToInt();
						if (num7 >= 0 && num8 >= 0)
						{
							byte b = (byte)((num7 << 4) | num8);
							i += 2;
							decoder.FlushBytes();
							decoder.AddByte(b);
							if (i + 1 < length - 2 && url[i + 1] == '%')
							{
								num7 = url[i + 1].HexToInt();
								num8 = url[i + 2].HexToInt();
								if (num7 >= 0 && num8 >= 0)
								{
									b = (byte)((num7 << 4) | num8);
									i += 2;
									decoder.AddByte(b);
									decoder.FlushBytes(checkChar: true);
								}
							}
							else
							{
								decoder.FlushBytes(checkChar: true);
							}
							continue;
						}
					}
				}
				if ((ch & 0xFF80) == 0)
				{
					decoder.AddByte((byte)ch);
				}
				else
				{
					decoder.AddChar(ch);
				}
			}
			return decoder.GetString();
		}

		public static string EncodeURL(this string text)
		{
			return Uri.EscapeDataString(text);
		}
	}
}