nsTextPaintStyle.h

Enable keyboard shortcuts

/* -*- 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);

  void GetTargetTextColors(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__