import FIREFOX_52_6_0esr_RELEASE from mozilla-esr52 hg repo

accessible/base/TextRange.h

@@ -0,0 +1,270 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=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 mozilla_a11y_TextRange_h__
+#define mozilla_a11y_TextRange_h__
+
+#include "mozilla/Move.h"
+#include "nsCaseTreatment.h"
+#include "nsRect.h"
+#include "nsTArray.h"
+
+ class nsIVariant;
+
+namespace mozilla {
+namespace a11y {
+
+class Accessible;
+class HyperTextAccessible;
+
+/**
+ * A text point (hyper text + offset), represents a boundary of text range.
+ */
+struct TextPoint final
+{
+  TextPoint(HyperTextAccessible* aContainer, int32_t aOffset) :
+    mContainer(aContainer), mOffset(aOffset) { }
+  TextPoint(const TextPoint& aPoint) :
+    mContainer(aPoint.mContainer), mOffset(aPoint.mOffset) { }
+
+  HyperTextAccessible* mContainer;
+  int32_t mOffset;
+
+  bool operator ==(const TextPoint& aPoint) const
+    { return mContainer == aPoint.mContainer && mOffset == aPoint.mOffset; }
+  bool operator <(const TextPoint& aPoint) const;
+};
+
+/**
+ * Represents a text range within the text control or document.
+ */
+class TextRange final
+{
+public:
+  TextRange(HyperTextAccessible* aRoot,
+            HyperTextAccessible* aStartContainer, int32_t aStartOffset,
+            HyperTextAccessible* aEndContainer, int32_t aEndOffset);
+  TextRange() {}
+  TextRange(TextRange&& aRange) :
+    mRoot(mozilla::Move(aRange.mRoot)),
+    mStartContainer(mozilla::Move(aRange.mStartContainer)),
+    mEndContainer(mozilla::Move(aRange.mEndContainer)),
+    mStartOffset(aRange.mStartOffset), mEndOffset(aRange.mEndOffset) {}
+
+  TextRange& operator= (TextRange&& aRange)
+  {
+    mRoot = mozilla::Move(aRange.mRoot);
+    mStartContainer = mozilla::Move(aRange.mStartContainer);
+    mEndContainer = mozilla::Move(aRange.mEndContainer);
+    mStartOffset = aRange.mStartOffset;
+    mEndOffset = aRange.mEndOffset;
+    return *this;
+  }
+
+  HyperTextAccessible* StartContainer() const { return mStartContainer; }
+  int32_t StartOffset() const { return mStartOffset; }
+  HyperTextAccessible* EndContainer() const { return mEndContainer; }
+  int32_t EndOffset() const { return mEndOffset; }
+
+  bool operator ==(const TextRange& aRange) const
+  {
+    return mStartContainer == aRange.mStartContainer &&
+      mStartOffset == aRange.mStartOffset &&
+      mEndContainer == aRange.mEndContainer && mEndOffset == aRange.mEndOffset;
+  }
+
+  TextPoint StartPoint() const { return TextPoint(mStartContainer, mStartOffset); }
+  TextPoint EndPoint() const { return TextPoint(mEndContainer, mEndOffset); }
+
+  /**
+   * Return a container containing both start and end points.
+   */
+  Accessible* Container() const;
+
+  /**
+   * Return a list of embedded objects enclosed by the text range (includes
+   * partially overlapped objects).
+   */
+  void EmbeddedChildren(nsTArray<Accessible*>* aChildren) const;
+
+  /**
+   * Return text enclosed by the range.
+   */
+  void Text(nsAString& aText) const;
+
+  /**
+   * Return list of bounding rects of the text range by lines.
+   */
+  void Bounds(nsTArray<nsIntRect> aRects) const;
+
+  enum ETextUnit {
+    eFormat,
+    eWord,
+    eLine,
+    eParagraph,
+    ePage,
+    eDocument
+  };
+
+  /**
+   * Move the range or its points on specified amount of given units.
+   */
+  void Move(ETextUnit aUnit, int32_t aCount)
+  {
+    MoveEnd(aUnit, aCount);
+    MoveStart(aUnit, aCount);
+  }
+  void MoveStart(ETextUnit aUnit, int32_t aCount)
+  {
+    MoveInternal(aUnit, aCount, *mStartContainer, mStartOffset,
+                 mEndContainer, mEndOffset);
+  }
+  void MoveEnd(ETextUnit aUnit, int32_t aCount)
+    { MoveInternal(aUnit, aCount, *mEndContainer, mEndOffset); }
+
+  /**
+   * Move the range points to the closest unit boundaries.
+   */
+  void Normalize(ETextUnit aUnit);
+
+  /**
+   * Crops the range if it overlaps the given accessible element boundaries,
+   * returns true if the range was cropped successfully.
+   */
+  bool Crop(Accessible* aContainer);
+
+  enum EDirection {
+    eBackward,
+    eForward
+  };
+
+  /**
+   * Return range enclosing the found text.
+   */
+  void FindText(const nsAString& aText, EDirection aDirection,
+                nsCaseTreatment aCaseSensitive, TextRange* aFoundRange) const;
+
+  enum EAttr {
+    eAnimationStyleAttr,
+    eAnnotationObjectsAttr,
+    eAnnotationTypesAttr,
+    eBackgroundColorAttr,
+    eBulletStyleAttr,
+    eCapStyleAttr,
+    eCaretBidiModeAttr,
+    eCaretPositionAttr,
+    eCultureAttr,
+    eFontNameAttr,
+    eFontSizeAttr,
+    eFontWeightAttr,
+    eForegroundColorAttr,
+    eHorizontalTextAlignmentAttr,
+    eIndentationFirstLineAttr,
+    eIndentationLeadingAttr,
+    eIndentationTrailingAttr,
+    eIsActiveAttr,
+    eIsHiddenAttr,
+    eIsItalicAttr,
+    eIsReadOnlyAttr,
+    eIsSubscriptAttr,
+    eIsSuperscriptAttr,
+    eLinkAttr,
+    eMarginBottomAttr,
+    eMarginLeadingAttr,
+    eMarginTopAttr,
+    eMarginTrailingAttr,
+    eOutlineStylesAttr,
+    eOverlineColorAttr,
+    eOverlineStyleAttr,
+    eSelectionActiveEndAttr,
+    eStrikethroughColorAttr,
+    eStrikethroughStyleAttr,
+    eStyleIdAttr,
+    eStyleNameAttr,
+    eTabsAttr,
+    eTextFlowDirectionsAttr,
+    eUnderlineColorAttr,
+    eUnderlineStyleAttr
+  };
+
+  /**
+   * Return range enclosing text having requested attribute.
+   */
+  void FindAttr(EAttr aAttr, nsIVariant* aValue, EDirection aDirection,
+                TextRange* aFoundRange) const;
+
+  /**
+   * Add/remove the text range from selection.
+   */
+  void AddToSelection() const;
+  void RemoveFromSelection() const;
+  void Select() const;
+
+  /**
+   * Scroll the text range into view.
+   */
+  enum EHowToAlign {
+    eAlignToTop,
+    eAlignToBottom
+  };
+  void ScrollIntoView(EHowToAlign aHow) const;
+
+  /**
+   * Return true if this TextRange object represents an actual range of text.
+   */
+  bool IsValid() const { return mRoot; }
+
+  void SetStartPoint(HyperTextAccessible* aContainer, int32_t aOffset)
+    { mStartContainer = aContainer; mStartOffset = aOffset; }
+  void SetEndPoint(HyperTextAccessible* aContainer, int32_t aOffset)
+    { mStartContainer = aContainer; mStartOffset = aOffset; }
+
+private:
+  TextRange(const TextRange& aRange) = delete;
+  TextRange& operator=(const TextRange& aRange) = delete;
+
+  friend class HyperTextAccessible;
+  friend class xpcAccessibleTextRange;
+
+  void Set(HyperTextAccessible* aRoot,
+           HyperTextAccessible* aStartContainer, int32_t aStartOffset,
+           HyperTextAccessible* aEndContainer, int32_t aEndOffset);
+
+  /**
+   * Text() method helper.
+   * @param  aText            [in,out] calculated text
+   * @param  aCurrent         [in] currently traversed node
+   * @param  aStartIntlOffset [in] start offset if current node is a text node
+   * @return                   true if calculation is not finished yet
+   */
+  bool TextInternal(nsAString& aText, Accessible* aCurrent,
+                    uint32_t aStartIntlOffset) const;
+
+  void MoveInternal(ETextUnit aUnit, int32_t aCount,
+                    HyperTextAccessible& aContainer, int32_t aOffset,
+                    HyperTextAccessible* aStopContainer = nullptr,
+                    int32_t aStopOffset = 0);
+
+  /**
+   * A helper method returning a common parent for two given accessible
+   * elements.
+   */
+  Accessible* CommonParent(Accessible* aAcc1, Accessible* aAcc2,
+                           nsTArray<Accessible*>* aParents1, uint32_t* aPos1,
+                           nsTArray<Accessible*>* aParents2, uint32_t* aPos2) const;
+
+  RefPtr<HyperTextAccessible> mRoot;
+  RefPtr<HyperTextAccessible> mStartContainer;
+  RefPtr<HyperTextAccessible> mEndContainer;
+  int32_t mStartOffset;
+  int32_t mEndOffset;
+};
+
+
+} // namespace a11y
+} // namespace mozilla
+
+#endif