/* -*- 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 mozilla_ContentEventHandler_h_ #define mozilla_ContentEventHandler_h_ #include "mozilla/EventForwards.h" #include "mozilla/dom/Selection.h" #include "nsCOMPtr.h" #include "nsIFrame.h" #include "nsINode.h" class nsPresContext; class nsRange; struct nsRect; namespace mozilla { enum LineBreakType { LINE_BREAK_TYPE_NATIVE, LINE_BREAK_TYPE_XP }; /* * Query Content Event Handler * ContentEventHandler is a helper class for EventStateManager. * The platforms request some content informations, e.g., the selected text, * the offset of the selected text and the text for specified range. * This class answers to NS_QUERY_* events from actual contents. */ class MOZ_STACK_CLASS ContentEventHandler { private: /** * RawRange is a helper class of ContentEventHandler class. The caller is * responsible for making sure the start/end nodes are in document order. * This is enforced by assertions in DEBUG builds. */ class MOZ_STACK_CLASS RawRange final { public: RawRange() = default; void Clear() { mRoot = nullptr; mStart = RangeBoundary(); mEnd = RangeBoundary(); } bool IsPositioned() const { return mStart.IsSet() && mEnd.IsSet(); } bool Collapsed() const { return mStart == mEnd && IsPositioned(); } nsINode* GetStartContainer() const { return mStart.Container(); } nsINode* GetEndContainer() const { return mEnd.Container(); } uint32_t StartOffset() const { return *mStart.Offset( RangeBoundary::OffsetFilter::kValidOrInvalidOffsets); } uint32_t EndOffset() const { return *mEnd.Offset(RangeBoundary::OffsetFilter::kValidOrInvalidOffsets); } nsIContent* StartRef() const { return mStart.Ref(); } nsIContent* EndRef() const { return mEnd.Ref(); } const RangeBoundary& Start() const { return mStart; } const RangeBoundary& End() const { return mEnd; } // XXX: Make these use RangeBoundaries... nsresult CollapseTo(const RawRangeBoundary& aBoundary) { return SetStartAndEnd(aBoundary, aBoundary); } nsresult SetStart(const RawRangeBoundary& aStart); nsresult SetEnd(const RawRangeBoundary& aEnd); // NOTE: These helpers can hide performance problems, as they perform a // search to find aStartOffset in aStartContainer. nsresult SetStart(nsINode* aStartContainer, uint32_t aStartOffset) { return SetStart(RawRangeBoundary(aStartContainer, aStartOffset)); } nsresult SetEnd(nsINode* aEndContainer, uint32_t aEndOffset) { return SetEnd(RawRangeBoundary(aEndContainer, aEndOffset)); } nsresult SetEndAfter(nsINode* aEndContainer); void SetStartAndEnd(const nsRange* aRange); nsresult SetStartAndEnd(const RawRangeBoundary& aStart, const RawRangeBoundary& aEnd); nsresult SelectNodeContents(nsINode* aNodeToSelectContents); private: inline void AssertStartIsBeforeOrEqualToEnd(); nsCOMPtr mRoot; RangeBoundary mStart; RangeBoundary mEnd; }; public: typedef dom::Selection Selection; explicit ContentEventHandler(nsPresContext* aPresContext); // Handle aEvent in the current process. nsresult HandleQueryContentEvent(WidgetQueryContentEvent* aEvent); // eQuerySelectedText event handler nsresult OnQuerySelectedText(WidgetQueryContentEvent* aEvent); // eQueryTextContent event handler nsresult OnQueryTextContent(WidgetQueryContentEvent* aEvent); // eQueryCaretRect event handler nsresult OnQueryCaretRect(WidgetQueryContentEvent* aEvent); // eQueryTextRect event handler nsresult OnQueryTextRect(WidgetQueryContentEvent* aEvent); // eQueryTextRectArray event handler nsresult OnQueryTextRectArray(WidgetQueryContentEvent* aEvent); // eQueryEditorRect event handler nsresult OnQueryEditorRect(WidgetQueryContentEvent* aEvent); // eQueryContentState event handler nsresult OnQueryContentState(WidgetQueryContentEvent* aEvent); // eQuerySelectionAsTransferable event handler nsresult OnQuerySelectionAsTransferable(WidgetQueryContentEvent* aEvent); // eQueryCharacterAtPoint event handler nsresult OnQueryCharacterAtPoint(WidgetQueryContentEvent* aEvent); // eQueryDOMWidgetHittest event handler nsresult OnQueryDOMWidgetHittest(WidgetQueryContentEvent* aEvent); // NS_SELECTION_* event MOZ_CAN_RUN_SCRIPT nsresult OnSelectionEvent(WidgetSelectionEvent* aEvent); protected: RefPtr mDocument; // mSelection is typically normal selection but if OnQuerySelectedText() // is called, i.e., handling eQuerySelectedText, it's the specified selection // by WidgetQueryContentEvent::mInput::mSelectionType. RefPtr mSelection; // mFirstSelectedRawRange is initialized from the first range of mSelection, // if it exists. Otherwise, it is reset by Clear(). RawRange mFirstSelectedRawRange; nsCOMPtr mRootContent; nsresult Init(WidgetQueryContentEvent* aEvent); nsresult Init(WidgetSelectionEvent* aEvent); nsresult InitBasic(bool aRequireFlush = true); nsresult InitCommon(SelectionType aSelectionType = SelectionType::eNormal, bool aRequireFlush = true); /** * InitRootContent() computes the root content of current focused editor. * * @param aNormalSelection This must be a Selection instance whose type is * SelectionType::eNormal. */ nsresult InitRootContent(Selection* aNormalSelection); public: // FlatText means the text that is generated from DOM tree. The BR elements // are replaced to native linefeeds. Other elements are ignored. // NodePosition stores a pair of node and offset in the node. // When mNode is an element and mOffset is 0, the start position means after // the open tag of mNode. // This is useful to receive one or more sets of them instead of nsRange. // This type is intended to be used for short-lived operations, and is thus // marked MOZ_STACK_CLASS. struct MOZ_STACK_CLASS NodePosition : public RangeBoundary { // Only when mNode is an element node and mOffset is 0, mAfterOpenTag is // referred. bool mAfterOpenTag = true; NodePosition() = default; NodePosition(nsINode* aContainer, int32_t aOffset) : RangeBoundary(aContainer, aOffset) {} NodePosition(nsINode* aContainer, nsIContent* aRef) : RangeBoundary(aContainer, aRef) {} explicit NodePosition(const nsIFrame::ContentOffsets& aContentOffsets) : RangeBoundary(aContentOffsets.content, aContentOffsets.offset) {} public: bool operator==(const NodePosition& aOther) const { return RangeBoundary::operator==(aOther) && mAfterOpenTag == aOther.mAfterOpenTag; } bool IsBeforeOpenTag() const { return IsSet() && Container()->IsElement() && !Ref() && !mAfterOpenTag; } bool IsImmediatelyAfterOpenTag() const { return IsSet() && Container()->IsElement() && !Ref() && mAfterOpenTag; } }; // NodePositionBefore isn't good name if Container() isn't an element node nor // Offset() is not 0, though, when Container() is an element node and mOffset // is 0, this is treated as before the open tag of Container(). struct NodePositionBefore final : public NodePosition { NodePositionBefore(nsINode* aContainer, int32_t aOffset) : NodePosition(aContainer, aOffset) { mAfterOpenTag = false; } NodePositionBefore(nsINode* aContainer, nsIContent* aRef) : NodePosition(aContainer, aRef) { mAfterOpenTag = false; } }; // Get the flatten text length in the range. // @param aStartPosition Start node and offset in the node of the range. // @param aEndPosition End node and offset in the node of the range. // @param aRootContent The root content of the editor or document. // aRootContent won't cause any text including // line breaks. // @param aLength The result of the flatten text length of the // range. // @param aLineBreakType Whether this computes flatten text length with // native line breakers on the platform or // with XP line breaker (\n). // @param aIsRemovingNode Should be true only when this is called from // nsIMutationObserver::ContentRemoved(). // When this is true, aStartPosition.mNode should // be the root node of removing nodes and mOffset // should be 0 and aEndPosition.mNode should be // same as aStartPosition.mNode and mOffset should // be number of the children of mNode. static nsresult GetFlatTextLengthInRange(const NodePosition& aStartPosition, const NodePosition& aEndPosition, nsIContent* aRootContent, uint32_t* aLength, LineBreakType aLineBreakType, bool aIsRemovingNode = false); // Computes the native text length between aStartOffset and aEndOffset of // aContent. aContent must be a text node. static uint32_t GetNativeTextLength(nsIContent* aContent, uint32_t aStartOffset, uint32_t aEndOffset); // Get the native text length of aContent. aContent must be a text node. static uint32_t GetNativeTextLength(nsIContent* aContent, uint32_t aMaxLength = UINT32_MAX); // Get the native text length which is inserted before aContent. // aContent should be an element. static uint32_t GetNativeTextLengthBefore(nsIContent* aContent, nsINode* aRootNode); protected: // Get the text length of aContent. aContent must be a text node. static uint32_t GetTextLength(nsIContent* aContent, LineBreakType aLineBreakType, uint32_t aMaxLength = UINT32_MAX); // Get the text length of a given range of a content node in // the given line break type. static uint32_t GetTextLengthInRange(nsIContent* aContent, uint32_t aXPStartOffset, uint32_t aXPEndOffset, LineBreakType aLineBreakType); // Get the contents in aContent (meaning all children of aContent) as plain // text. E.g., specifying mRootContent gets whole text in it. // Note that the result is not same as .textContent. The result is // optimized for native IMEs. For example,
element and some block // elements causes "\n" (or "\r\n"), see also ShouldBreakLineBefore(). nsresult GenerateFlatTextContent(nsIContent* aContent, nsString& aString, LineBreakType aLineBreakType); // Get the contents of aRange as plain text. nsresult GenerateFlatTextContent(const RawRange& aRawRange, nsString& aString, LineBreakType aLineBreakType); // Get offset of start of aRange. Note that the result includes the length // of line breaker caused by the start of aContent because aRange never // includes the line breaker caused by its start node. nsresult GetStartOffset(const RawRange& aRawRange, uint32_t* aOffset, LineBreakType aLineBreakType); // Check if we should insert a line break before aContent. // This should return false only when aContent is an html element which // is typically used in a paragraph like . static bool ShouldBreakLineBefore(nsIContent* aContent, nsINode* aRootNode); // Get the line breaker length. static inline uint32_t GetBRLength(LineBreakType aLineBreakType); static LineBreakType GetLineBreakType(WidgetQueryContentEvent* aEvent); static LineBreakType GetLineBreakType(WidgetSelectionEvent* aEvent); static LineBreakType GetLineBreakType(bool aUseNativeLineBreak); // Returns focused content (including its descendant documents). nsIContent* GetFocusedContent(); // Returns true if the content is a plugin host. bool IsPlugin(nsIContent* aContent); // QueryContentRect() sets the rect of aContent's frame(s) to aEvent. nsresult QueryContentRect(nsIContent* aContent, WidgetQueryContentEvent* aEvent); // Initialize aRawRange from the offset of FlatText and the text length. // If aExpandToClusterBoundaries is true, the start offset and the end one are // expanded to nearest cluster boundaries. nsresult SetRawRangeFromFlatTextOffset(RawRange* aRawRange, uint32_t aOffset, uint32_t aLength, LineBreakType aLineBreakType, bool aExpandToClusterBoundaries, uint32_t* aNewOffset = nullptr, nsIContent** aLastTextNode = nullptr); // If the aCollapsedRawRange isn't in text node but next to a text node, // this method modifies it in the text node. Otherwise, not modified. nsresult AdjustCollapsedRangeMaybeIntoTextNode(RawRange& aCollapsedRawRange); // Convert the frame relative offset to be relative to the root frame of the // root presContext (but still measured in appUnits of aFrame's presContext). nsresult ConvertToRootRelativeOffset(nsIFrame* aFrame, nsRect& aRect); // Expand aXPOffset to the nearest offset in cluster boundary. aForward is // true, it is expanded to forward. nsresult ExpandToClusterBoundary(nsIContent* aContent, bool aForward, uint32_t* aXPOffset); typedef nsTArray FontRangeArray; static void AppendFontRanges(FontRangeArray& aFontRanges, nsIContent* aContent, uint32_t aBaseOffset, uint32_t aXPStartOffset, uint32_t aXPEndOffset, LineBreakType aLineBreakType); nsresult GenerateFlatFontRanges(const RawRange& aRawRange, FontRangeArray& aFontRanges, uint32_t& aLength, LineBreakType aLineBreakType); nsresult QueryTextRectByRange(const RawRange& aRawRange, LayoutDeviceIntRect& aRect, WritingMode& aWritingMode); struct MOZ_STACK_CLASS FrameAndNodeOffset final { // mFrame is safe since this can live in only stack class and // ContentEventHandler doesn't modify layout after // ContentEventHandler::Init() flushes pending layout. In other words, // this struct shouldn't be used before calling // ContentEventHandler::Init(). nsIFrame* mFrame; // offset in the node of mFrame int32_t mOffsetInNode; FrameAndNodeOffset() : mFrame(nullptr), mOffsetInNode(-1) {} FrameAndNodeOffset(nsIFrame* aFrame, int32_t aStartOffsetInNode) : mFrame(aFrame), mOffsetInNode(aStartOffsetInNode) {} nsIFrame* operator->() { return mFrame; } const nsIFrame* operator->() const { return mFrame; } operator nsIFrame*() { return mFrame; } operator const nsIFrame*() const { return mFrame; } bool IsValid() const { return mFrame && mOffsetInNode >= 0; } }; // Get first frame after the start of the given range for computing text rect. // This returns invalid FrameAndNodeOffset if there is no content which // should affect to computing text rect in the range. mOffsetInNode is start // offset in the frame. FrameAndNodeOffset GetFirstFrameInRangeForTextRect(const RawRange& aRawRange); // Get last frame before the end of the given range for computing text rect. // This returns invalid FrameAndNodeOffset if there is no content which // should affect to computing text rect in the range. mOffsetInNode is end // offset in the frame. FrameAndNodeOffset GetLastFrameInRangeForTextRect(const RawRange& aRawRange); struct MOZ_STACK_CLASS FrameRelativeRect final { // mRect is relative to the mBaseFrame's position. nsRect mRect; nsIFrame* mBaseFrame; FrameRelativeRect() : mBaseFrame(nullptr) {} explicit FrameRelativeRect(nsIFrame* aBaseFrame) : mBaseFrame(aBaseFrame) {} FrameRelativeRect(const nsRect& aRect, nsIFrame* aBaseFrame) : mRect(aRect), mBaseFrame(aBaseFrame) {} bool IsValid() const { return mBaseFrame != nullptr; } // Returns an nsRect relative to aBaseFrame instead of mBaseFrame. nsRect RectRelativeTo(nsIFrame* aBaseFrame) const; }; // Returns a rect for line breaker before the node of aFrame (If aFrame is // a
frame or a block level frame, it causes a line break at its // element's open tag, see also ShouldBreakLineBefore()). Note that this // doesn't check if aFrame should cause line break in non-debug build. FrameRelativeRect GetLineBreakerRectBefore(nsIFrame* aFrame); // Returns a line breaker rect after aTextContent as there is a line breaker // immediately after aTextContent. This is useful when following block // element causes a line break before it and it needs to compute the line // breaker's rect. For example, if there is |

abc

def

|, the // rect of 2nd

's line breaker should be at right of "c" in the first //

, not the start of 2nd

. The result is relative to the last text // frame which represents the last character of aTextContent. FrameRelativeRect GuessLineBreakerRectAfter(nsIContent* aTextContent); // Returns a guessed first rect. I.e., it may be different from actual // caret when selection is collapsed at start of aFrame. For example, this // guess the caret rect only with the content box of aFrame and its font // height like: // +-aFrame----------------- (border box) // | // | +--------------------- (content box) // | | I // ^ guessed caret rect // However, actual caret is computed with more information like line-height, // child frames of aFrame etc. But this does not emulate actual caret // behavior exactly for simpler and faster code because it's difficult and // we're not sure it's worthwhile to do it with complicated implementation. FrameRelativeRect GuessFirstCaretRectIn(nsIFrame* aFrame); // Make aRect non-empty. If width and/or height is 0, these methods set them // to 1. Note that it doesn't set nsRect's width nor height to one device // pixel because using nsRect::ToOutsidePixels() makes actual width or height // to 2 pixels because x and y may not be aligned to device pixels. void EnsureNonEmptyRect(nsRect& aRect) const; void EnsureNonEmptyRect(LayoutDeviceIntRect& aRect) const; }; } // namespace mozilla #endif // mozilla_ContentEventHandler_h_