csharp/client/result/URIResultParser.cs

   1 /*\r
   2 * Copyright 2007 ZXing authors\r
   3 *\r
   4 * Licensed under the Apache License, Version 2.0 (the "License");\r
   5 * you may not use this file except in compliance with the License.\r
   6 * You may obtain a copy of the License at\r
   7 *\r
   8 *      http://www.apache.org/licenses/LICENSE-2.0\r
   9 *\r
  10 * Unless required by applicable law or agreed to in writing, software\r
  11 * distributed under the License is distributed on an "AS IS" BASIS,\r
  12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.\r
  13 * See the License for the specific language governing permissions and\r
  14 * limitations under the License.\r
  15 */\r
  16 using System;\r
  17 using Result = com.google.zxing.Result;\r
  18 namespace com.google.zxing.client.result\r
  19 {\r
  20         \r
  21         /// <summary> Tries to parse results that are a URI of some kind.\r
  22         /// \r
  23         /// </summary>\r
  24         /// <author>  Sean Owen\r
  25         /// </author>\r
  26         /// <author>www.Redivivus.in (suraj.supekar@redivivus.in) - Ported from ZXING Java Source \r
  27         /// </author>\r
  28         sealed class URIResultParser:ResultParser\r
  29         {\r
  30                 \r
  31                 private URIResultParser()\r
  32                 {\r
  33                 }\r
  34                 \r
  35                 public static URIParsedResult parse(Result result)\r
  36                 {\r
  37                         System.String rawText = result.Text;\r
  38                         // We specifically handle the odd "URL" scheme here for simplicity\r
  39                         if (rawText != null && rawText.StartsWith("URL:"))\r
  40                         {\r
  41                                 rawText = rawText.Substring(4);\r
  42                         }\r
  43                         if (!isBasicallyValidURI(rawText))\r
  44                         {\r
  45                                 return null;\r
  46                         }\r
  47                         return new URIParsedResult(rawText, null);\r
  48                 }\r
  49                 \r
  50                 /// <summary> Determines whether a string is not obviously not a URI. This implements crude checks; this class does not\r
  51                 /// intend to strictly check URIs as its only function is to represent what is in a barcode, but, it does\r
  52                 /// need to know when a string is obviously not a URI.\r
  53                 /// </summary>\r
  54                 internal static bool isBasicallyValidURI(System.String uri)\r
  55                 {\r
  56                         if (uri == null || uri.IndexOf(' ') >= 0 || uri.IndexOf('\n') >= 0)\r
  57                         {\r
  58                                 return false;\r
  59                         }\r
  60                         // Look for period in a domain but followed by at least a two-char TLD\r
  61                         // Forget strings that don't have a valid-looking protocol\r
  62                         int period = uri.IndexOf('.');\r
  63                         if (period >= uri.Length - 2)\r
  64                         {\r
  65                                 return false;\r
  66                         }\r
  67                         int colon = uri.IndexOf(':');\r
  68                         if (period < 0 && colon < 0)\r
  69                         {\r
  70                                 return false;\r
  71                         }\r
  72                         if (colon >= 0)\r
  73                         {\r
  74                                 if (period < 0 || period > colon)\r
  75                                 {\r
  76                                         // colon ends the protocol\r
  77                                         for (int i = 0; i < colon; i++)\r
  78                                         {\r
  79                                                 char c = uri[i];\r
  80                                                 if ((c < 'a' || c > 'z') && (c < 'A' || c > 'Z'))\r
  81                                                 {\r
  82                                                         return false;\r
  83                                                 }\r
  84                                         }\r
  85                                 }\r
  86                                 else\r
  87                                 {\r
  88                                         // colon starts the port; crudely look for at least two numbers\r
  89                                         if (colon >= uri.Length - 2)\r
  90                                         {\r
  91                                                 return false;\r
  92                                         }\r
  93                                         for (int i = colon + 1; i < colon + 3; i++)\r
  94                                         {\r
  95                                                 char c = uri[i];\r
  96                                                 if (c < '0' || c > '9')\r
  97                                                 {\r
  98                                                         return false;\r
  99                                                 }\r
 100                                         }\r
 101                                 }\r
 102                         }\r
 103                         return true;\r
 104                 }\r
 105         }\r
 106 }