mcs/class/System.Net.Http/System.Net.Http.Headers/StringWithQualityHeaderValue.cs

   1 //
   2 // StringWithQualityHeaderValue.cs
   3 //
   4 // Authors:
   5 //      Marek Safar  <marek.safar@gmail.com>
   6 //
   7 // Copyright (C) 2011 Xamarin Inc (http://www.xamarin.com)
   8 //
   9 // Permission is hereby granted, free of charge, to any person obtaining
  10 // a copy of this software and associated documentation files (the
  11 // "Software"), to deal in the Software without restriction, including
  12 // without limitation the rights to use, copy, modify, merge, publish,
  13 // distribute, sublicense, and/or sell copies of the Software, and to
  14 // permit persons to whom the Software is furnished to do so, subject to
  15 // the following conditions:
  16 //
  17 // The above copyright notice and this permission notice shall be
  18 // included in all copies or substantial portions of the Software.
  19 //
  20 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  21 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  22 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  23 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  24 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  25 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  26 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  27 //
  28
  29 using System.Globalization;
  30 namespace System.Net.Http.Headers
  31 {
  32         public class StringWithQualityHeaderValue : ICloneable
  33         {
  34                 public StringWithQualityHeaderValue (string value)
  35                 {
  36                         Parser.Token.Check (value);
  37                         this.Value = value;
  38                 }
  39
  40                 public StringWithQualityHeaderValue (string value, double quality)
  41                         : this (value)
  42                 {
  43                         if (quality < 0 || quality > 1)
  44                                 throw new ArgumentOutOfRangeException ("quality");
  45
  46                         Quality = quality;
  47                 }
  48
  49                 private StringWithQualityHeaderValue ()
  50                 {
  51                 }
  52
  53                 public double? Quality { get; private set; }
  54                 public string Value { get; private set; }
  55
  56                 object ICloneable.Clone ()
  57                 {
  58                         return MemberwiseClone ();
  59                 }
  60
  61                 public override bool Equals (object obj)
  62                 {
  63                         var source = obj as StringWithQualityHeaderValue;
  64                         return source != null &&
  65                                 string.Equals (source.Value, Value, StringComparison.OrdinalIgnoreCase) &&
  66                                 source.Quality == Quality;
  67                 }
  68
  69                 public override int GetHashCode ()
  70                 {
  71                         return Value.ToLowerInvariant ().GetHashCode () ^ Quality.GetHashCode ();
  72                 }
  73
  74                 public static StringWithQualityHeaderValue Parse (string input)
  75                 {
  76                         StringWithQualityHeaderValue value;
  77                         if (TryParse (input, out value))
  78                                 return value;
  79
  80                         throw new FormatException (input);
  81                 }
  82
  83                 public static bool TryParse (string input, out StringWithQualityHeaderValue parsedValue)
  84                 {
  85                         parsedValue = null;
  86
  87                         var lexer = new Lexer (input);
  88                         var t = lexer.Scan ();
  89                         if (t != Token.Type.Token)
  90                                 return false;
  91
  92                         var value = new StringWithQualityHeaderValue ();
  93                         value.Value = lexer.GetStringValue (t);
  94
  95                         t = lexer.Scan ();
  96                         if (t == Token.Type.SeparatorSemicolon) {
  97                                 t = lexer.Scan ();
  98                                 if (t != Token.Type.Token)
  99                                         return false;
 100
 101                                 var s = lexer.GetStringValue (t);
 102                                 if (s != "q" && s != "Q")
 103                                         return false;
 104
 105                                 t = lexer.Scan ();
 106                                 if (t != Token.Type.SeparatorEqual)
 107                                         return false;
 108
 109                                 t = lexer.Scan ();
 110
 111                                 double d;
 112                                 if (!lexer.TryGetDoubleValue (t, out d))
 113                                         return false;
 114
 115                                 if (d > 1)
 116                                         return false;
 117
 118                                 value.Quality = d;
 119
 120                                 t = lexer.Scan ();
 121                         }
 122
 123                         if (t != Token.Type.End)
 124                                 return false;
 125
 126                         parsedValue = value;
 127                         return true;
 128                 }
 129
 130                 public override string ToString ()
 131                 {
 132                         if (Quality != null)
 133                                 return Value + "; q=" + Quality.Value.ToString ("0.0##", CultureInfo.InvariantCulture);
 134
 135                         return Value;
 136                 }
 137         }
 138 }