mcs/class/corlib/Mono.Globalization.Unicode/CodePointIndexer.cs

   1 using System;
   2 using System.Globalization;
   3 using System.Text;
   4
   5 namespace Mono.Globalization.Unicode
   6 {
   7         internal class CodePointIndexer
   8         {
   9                 // This class is used to compactize indexes to limited areas so that
  10                 // we can save extraneous 0,0,0,0,0... in the tables.
  11                 internal class TableRange
  12                 {
  13                         public TableRange (int start, int end, int indexStart)
  14                         {
  15                                 Start = start;
  16                                 End = end;
  17                                 Count = End - Start;
  18                                 IndexStart = indexStart;
  19                                 IndexEnd = IndexStart + Count;
  20                         }
  21
  22                         public readonly int Start;
  23                         public readonly int End;
  24                         public readonly int Count;
  25                         public readonly int IndexStart;
  26                         public readonly int IndexEnd;
  27                 }
  28
  29                 readonly TableRange [] ranges;
  30 #if DumpFullArray
  31                 public const int TotalCount = char.MaxValue + 1;
  32 #else
  33                 public readonly int TotalCount;
  34
  35                 public CodePointIndexer (int [] starts, int [] ends)
  36                 {
  37                         ranges = new TableRange [starts.Length];
  38                         for (int i = 0; i < ranges.Length; i++)
  39                                 ranges [i] = new TableRange (starts [i],
  40                                         ends [i], i == 0 ? 0 :
  41                                         ranges [i - 1].IndexStart +
  42                                         ranges [i - 1].Count);
  43                         for (int i = 0; i < ranges.Length; i++)
  44                                 TotalCount += ranges [i].Count;
  45
  46 //                      for (int i = 0; i < ranges.Length; i++)
  47 //                              Console.Error.WriteLine ("RANGES [{0}] : {1:x} to {2:x} index {3:x} to {4:x}. total {5:x}", i, ranges [i].Start, ranges [i].End, ranges [i].IndexStart, ranges [i].IndexEnd, ranges [i].Count);
  48 //                      Console.Error.WriteLine ("Total items: {0:X} ({1})", TotalCount, TotalCount);
  49                 }
  50 #endif
  51
  52                 public int GetIndexForCodePoint (int cp)
  53                 {
  54 #if DumpFullArray
  55                         return cp;
  56 #else
  57                         for (int t = 0; t < ranges.Length; t++)
  58                                 if (ranges [t].Start <= cp && cp < ranges [t].End)
  59                                         return cp - ranges [t].Start + ranges [t].IndexStart;
  60                         return 0;
  61 //                      return -1;
  62 //                      throw new SystemException (String.Format ("Should not happen: no map definition for cp {0:x}({1})", cp, (char) cp));
  63 #endif
  64                 }
  65
  66                 public int GetCodePointForIndex (int i)
  67                 {
  68 #if DumpFullArray
  69                         return i;
  70 #else
  71                         for (int t = 0; t < ranges.Length; t++) {
  72                                 if (t > 0 && i < ranges [t - 1].IndexEnd)
  73                                         return -1; // unexpected out of range
  74                                 if (ranges [t].IndexStart <= i &&
  75                                         i < ranges [t].IndexEnd)
  76                                         return i - ranges [t].IndexStart
  77                                                 + ranges [t].Start;
  78                         }
  79                         return 0;
  80 //                      return -1;
  81 //                      throw new SystemException (String.Format ("Should not happen: no map definition for index {0:x}({1})", i, i));
  82 #endif
  83                 }
  84         }
  85 }