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 using System.Collections.Generic;
  31
  32 namespace System.Net.Http.Headers
  33 {
  34         public class StringWithQualityHeaderValue : ICloneable
  35         {
  36                 public StringWithQualityHeaderValue (string value)
  37                 {
  38                         Parser.Token.Check (value);
  39                         this.Value = value;
  40                 }
  41
  42                 public StringWithQualityHeaderValue (string value, double quality)
  43                         : this (value)
  44                 {
  45                         if (quality < 0 || quality > 1)
  46                                 throw new ArgumentOutOfRangeException ("quality");
  47
  48                         Quality = quality;
  49                 }
  50
  51                 private StringWithQualityHeaderValue ()
  52                 {
  53                 }
  54
  55                 public double? Quality { get; private set; }
  56                 public string Value { get; private set; }
  57
  58                 object ICloneable.Clone ()
  59                 {
  60                         return MemberwiseClone ();
  61                 }
  62
  63                 public override bool Equals (object obj)
  64                 {
  65                         var source = obj as StringWithQualityHeaderValue;
  66                         return source != null &&
  67                                 string.Equals (source.Value, Value, StringComparison.OrdinalIgnoreCase) &&
  68                                 source.Quality == Quality;
  69                 }
  70
  71                 public override int GetHashCode ()
  72                 {
  73                         return Value.ToLowerInvariant ().GetHashCode () ^ Quality.GetHashCode ();
  74                 }
  75
  76                 public static StringWithQualityHeaderValue Parse (string input)
  77                 {
  78                         StringWithQualityHeaderValue value;
  79                         if (TryParse (input, out value))
  80                                 return value;
  81
  82                         throw new FormatException (input);
  83                 }
  84
  85                 public static bool TryParse (string input, out StringWithQualityHeaderValue parsedValue)
  86                 {
  87                         var lexer = new Lexer (input);
  88                         Token token;
  89                         if (TryParseElement (lexer, out parsedValue, out token) && token == Token.Type.End)
  90                                 return true;
  91
  92                         parsedValue = null;
  93                         return false;
  94                 }
  95
  96                 internal static bool TryParse (string input, int minimalCount, out List<StringWithQualityHeaderValue> result)
  97                 {
  98                         return CollectionParser.TryParse (input, minimalCount, TryParseElement, out result);
  99                 }
 100
 101                 static bool TryParseElement (Lexer lexer, out StringWithQualityHeaderValue parsedValue, out Token t)
 102                 {
 103                         parsedValue = null;
 104                         t = lexer.Scan ();
 105                         if (t != Token.Type.Token)
 106                                 return false;
 107
 108                         var value = new StringWithQualityHeaderValue ();
 109                         value.Value = lexer.GetStringValue (t);
 110
 111                         t = lexer.Scan ();
 112                         if (t == Token.Type.SeparatorSemicolon) {
 113                                 t = lexer.Scan ();
 114                                 if (t != Token.Type.Token)
 115                                         return false;
 116
 117                                 var s = lexer.GetStringValue (t);
 118                                 if (s != "q" && s != "Q")
 119                                         return false;
 120
 121                                 t = lexer.Scan ();
 122                                 if (t != Token.Type.SeparatorEqual)
 123                                         return false;
 124
 125                                 t = lexer.Scan ();
 126
 127                                 double d;
 128                                 if (!lexer.TryGetDoubleValue (t, out d))
 129                                         return false;
 130
 131                                 if (d > 1)
 132                                         return false;
 133
 134                                 value.Quality = d;
 135
 136                                 t = lexer.Scan ();
 137                         }
 138
 139                         parsedValue = value;
 140                         return true;
 141                 }
 142
 143                 public override string ToString ()
 144                 {
 145                         if (Quality != null)
 146                                 return Value + "; q=" + Quality.Value.ToString ("0.0##", CultureInfo.InvariantCulture);
 147
 148                         return Value;
 149                 }
 150         }
 151 }