ui/gfx/range/range.h

   1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef UI_GFX_RANGE_RANGE_H_
   6 #define UI_GFX_RANGE_RANGE_H_
   7
   8 #include <ostream>
   9 #include <string>
  10
  11 #include "base/basictypes.h"
  12 #include "ui/gfx/gfx_export.h"
  13
  14 #if defined(OS_MACOSX)
  15 #if __OBJC__
  16 #import <Foundation/Foundation.h>
  17 #else
  18 typedef struct _NSRange NSRange;
  19 #endif
  20 #endif  // defined(OS_MACOSX)
  21
  22 #if defined(OS_WIN)
  23 #include <windows.h>
  24 #include <richedit.h>
  25 #endif
  26
  27 namespace gfx {
  28
  29 // A Range contains two integer values that represent a numeric range, like the
  30 // range of characters in a text selection. A range is made of a start and end
  31 // position; when they are the same, the Range is akin to a caret. Note that
  32 // |start_| can be greater than |end_| to respect the directionality of the
  33 // range.
  34 class GFX_EXPORT Range {
  35  public:
  36   // Creates an empty range {0,0}.
  37   Range();
  38
  39   // Initializes the range with a start and end.
  40   Range(size_t start, size_t end);
  41
  42   // Initializes the range with the same start and end positions.
  43   explicit Range(size_t position);
  44
  45   // Platform constructors.
  46 #if defined(OS_MACOSX)
  47   explicit Range(const NSRange& range);
  48 #elif defined(OS_WIN)
  49   // The |total_length| paramater should be used if the CHARRANGE is set to
  50   // {0,-1} to indicate the whole range.
  51   Range(const CHARRANGE& range, LONG total_length = -1);
  52 #endif
  53
  54   // Returns a range that is invalid, which is {size_t_max,size_t_max}.
  55   static const Range InvalidRange();
  56
  57   // Checks if the range is valid through comparision to InvalidRange().
  58   bool IsValid() const;
  59
  60   // Getters and setters.
  61   size_t start() const { return start_; }
  62   void set_start(size_t start) { start_ = start; }
  63
  64   size_t end() const { return end_; }
  65   void set_end(size_t end) { end_ = end; }
  66
  67   // Returns the absolute value of the length.
  68   size_t length() const {
  69     ptrdiff_t length = end() - start();
  70     return length >= 0 ? length : -length;
  71   }
  72
  73   bool is_reversed() const { return start() > end(); }
  74   bool is_empty() const { return start() == end(); }
  75
  76   // Returns the minimum and maximum values.
  77   size_t GetMin() const;
  78   size_t GetMax() const;
  79
  80   bool operator==(const Range& other) const;
  81   bool operator!=(const Range& other) const;
  82   bool EqualsIgnoringDirection(const Range& other) const;
  83
  84   // Returns true if this range intersects the specified |range|.
  85   bool Intersects(const Range& range) const;
  86
  87   // Returns true if this range contains the specified |range|.
  88   bool Contains(const Range& range) const;
  89
  90   // Computes the intersection of this range with the given |range|.
  91   // If they don't intersect, it returns an InvalidRange().
  92   // The returned range is always empty or forward (never reversed).
  93   Range Intersect(const Range& range) const;
  94
  95 #if defined(OS_MACOSX)
  96   Range& operator=(const NSRange& range);
  97
  98   // NSRange does not store the directionality of a range, so if this
  99   // is_reversed(), the range will get flipped when converted to an NSRange.
 100   NSRange ToNSRange() const;
 101 #elif defined(OS_WIN)
 102   CHARRANGE ToCHARRANGE() const;
 103 #endif
 104   // GTK+ has no concept of a range.
 105
 106   std::string ToString() const;
 107
 108  private:
 109   size_t start_;
 110   size_t end_;
 111 };
 112
 113 GFX_EXPORT std::ostream& operator<<(std::ostream& os, const Range& range);
 114
 115 }  // namespace gfx
 116
 117 #endif  // UI_GFX_RANGE_RANGE_H_