summaryrefslogtreecommitdiffstats
path: root/layout/generic/nsTextPaintStyle.h
blob: adf28fdad8f705264c3aa9d88c82f4f3c2cbd0c1 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

#ifndef nsTextPaintStyle_h__
#define nsTextPaintStyle_h__

#include "mozilla/Attributes.h"
#include "mozilla/ComputedStyle.h"
#include "mozilla/EnumeratedArray.h"
#include "mozilla/Span.h"

#include "nsAtomHashKeys.h"
#include "nsISelectionController.h"
#include "nsTHashMap.h"

class nsTextFrame;
class nsPresContext;

namespace mozilla {
enum class StyleTextDecorationStyle : uint8_t;
}

/**
 * This helper object computes colors used for painting, and also IME
 * underline information. The data is computed lazily and cached as necessary.
 * These live for just the duration of one paint operation.
 */
class MOZ_STACK_CLASS nsTextPaintStyle {
  using ComputedStyle = mozilla::ComputedStyle;
  using SelectionType = mozilla::SelectionType;
  using StyleTextDecorationStyle = mozilla::StyleTextDecorationStyle;
  using StyleSimpleShadow = mozilla::StyleSimpleShadow;

 public:
  explicit nsTextPaintStyle(nsTextFrame* aFrame);

  void SetResolveColors(bool aResolveColors) {
    mResolveColors = aResolveColors;
  }

  nscolor GetTextColor();

  // SVG text has its own painting process, so we should never get its stroke
  // property from here.
  nscolor GetWebkitTextStrokeColor();
  float GetWebkitTextStrokeWidth();

  // Index used to look up styles for different types of selection.
  enum class SelectionStyleIndex : uint8_t {
    RawInput = 0,
    SelRawText,
    ConvText,
    SelConvText,
    SpellChecker,
    // Not an actual enum value; used to size the array of styles.
    Count,
  };

  /**
   * Compute the colors for normally-selected text. Returns false if
   * the normal selection is not being displayed.
   */
  bool GetSelectionColors(nscolor* aForeColor, nscolor* aBackColor);
  void GetHighlightColors(nscolor* aForeColor, nscolor* aBackColor);
  // Computes colors for custom highlights.
  // Returns false if there are no rules associated with `aHighlightName`.
  bool GetCustomHighlightTextColor(nsAtom* aHighlightName, nscolor* aForeColor);
  bool GetCustomHighlightBackgroundColor(nsAtom* aHighlightName,
                                         nscolor* aBackColor);
  void GetURLSecondaryColor(nscolor* aForeColor);
  void GetIMESelectionColors(SelectionStyleIndex aIndex, nscolor* aForeColor,
                             nscolor* aBackColor);
  // if this returns false, we don't need to draw underline.
  bool GetSelectionUnderlineForPaint(SelectionStyleIndex aIndex,
                                     nscolor* aLineColor, float* aRelativeSize,
                                     StyleTextDecorationStyle* aStyle);

  // if this returns false, we don't need to draw underline.
  static bool GetSelectionUnderline(nsIFrame*, SelectionStyleIndex aIndex,
                                    nscolor* aLineColor, float* aRelativeSize,
                                    StyleTextDecorationStyle* aStyle);

  // if this returns false, no text-shadow was specified for the selection
  // and the *aShadow parameter was not modified.
  bool GetSelectionShadow(mozilla::Span<const StyleSimpleShadow>* aShadows);

  nsPresContext* PresContext() const { return mPresContext; }

  static SelectionStyleIndex GetUnderlineStyleIndexForSelectionType(
      SelectionType aSelectionType) {
    switch (aSelectionType) {
      case SelectionType::eIMERawClause:
        return SelectionStyleIndex::RawInput;
      case SelectionType::eIMESelectedRawClause:
        return SelectionStyleIndex::SelRawText;
      case SelectionType::eIMEConvertedClause:
        return SelectionStyleIndex::ConvText;
      case SelectionType::eIMESelectedClause:
        return SelectionStyleIndex::SelConvText;
      case SelectionType::eSpellCheck:
        return SelectionStyleIndex::SpellChecker;
      default:
        NS_WARNING("non-IME selection type");
        return SelectionStyleIndex::RawInput;
    }
  }

  nscolor GetSystemFieldForegroundColor();
  nscolor GetSystemFieldBackgroundColor();

 protected:
  nsTextFrame* mFrame;
  nsPresContext* mPresContext;
  bool mInitCommonColors;
  bool mInitSelectionColorsAndShadow;
  bool mResolveColors;

  // Selection data

  nscolor mSelectionTextColor;
  nscolor mSelectionBGColor;
  RefPtr<ComputedStyle> mSelectionPseudoStyle;
  nsTHashMap<RefPtr<nsAtom>, RefPtr<ComputedStyle>>
      mCustomHighlightPseudoStyles;

  // Common data

  int32_t mSufficientContrast;
  nscolor mFrameBackgroundColor;
  nscolor mSystemFieldForegroundColor;
  nscolor mSystemFieldBackgroundColor;

  // selection colors and underline info, the colors are resolved colors if
  // mResolveColors is true (which is the default), i.e., the foreground color
  // and background color are swapped if it's needed. And also line color will
  // be resolved from them.
  struct nsSelectionStyle {
    nscolor mTextColor;
    nscolor mBGColor;
    nscolor mUnderlineColor;
    StyleTextDecorationStyle mUnderlineStyle;
    float mUnderlineRelativeSize;
  };
  mozilla::EnumeratedArray<SelectionStyleIndex,
                           mozilla::Maybe<nsSelectionStyle>,
                           size_t(SelectionStyleIndex::Count)>
      mSelectionStyle;

  // Color initializations
  void InitCommonColors();
  bool InitSelectionColorsAndShadow();

  nsSelectionStyle* SelectionStyle(SelectionStyleIndex aIndex);
  nsSelectionStyle InitSelectionStyle(SelectionStyleIndex aIndex);

  // Ensures sufficient contrast between the frame background color and the
  // selection background color, and swaps the selection text and background
  // colors accordingly.
  bool EnsureSufficientContrast(nscolor* aForeColor, nscolor* aBackColor);

  nscolor GetResolvedForeColor(nscolor aColor, nscolor aDefaultForeColor,
                               nscolor aBackColor);
};

#endif  // nsTextPaintStyle_h__