michael@0: /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
michael@0: /* This Source Code Form is subject to the terms of the Mozilla Public
michael@0:  * License, v. 2.0. If a copy of the MPL was not distributed with this
michael@0:  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
michael@0: 
michael@0: /*
michael@0:  * base class for rendering objects that can be split across lines,
michael@0:  * columns, or pages
michael@0:  */
michael@0: 
michael@0: #ifndef nsSplittableFrame_h___
michael@0: #define nsSplittableFrame_h___
michael@0: 
michael@0: #include "mozilla/Attributes.h"
michael@0: #include "nsFrame.h"
michael@0: 
michael@0: // Derived class that allows splitting
michael@0: class nsSplittableFrame : public nsFrame
michael@0: {
michael@0: public:
michael@0:   NS_DECL_FRAMEARENA_HELPERS
michael@0: 
michael@0:   virtual void Init(nsIContent*      aContent,
michael@0:                     nsIFrame*        aParent,
michael@0:                     nsIFrame*        aPrevInFlow) MOZ_OVERRIDE;
michael@0:   
michael@0:   virtual nsSplittableType GetSplittableType() const MOZ_OVERRIDE;
michael@0: 
michael@0:   virtual void DestroyFrom(nsIFrame* aDestructRoot) MOZ_OVERRIDE;
michael@0: 
michael@0:   /*
michael@0:    * Frame continuations can be either fluid or not:
michael@0:    * Fluid continuations ("in-flows") are the result of line breaking, 
michael@0:    * column breaking, or page breaking.
michael@0:    * Other (non-fluid) continuations can be the result of BiDi frame splitting.
michael@0:    * A "flow" is a chain of fluid continuations.
michael@0:    */
michael@0:   
michael@0:   // Get the previous/next continuation, regardless of its type (fluid or non-fluid).
michael@0:   virtual nsIFrame* GetPrevContinuation() const MOZ_OVERRIDE;
michael@0:   virtual nsIFrame* GetNextContinuation() const MOZ_OVERRIDE;
michael@0: 
michael@0:   // Set a previous/next non-fluid continuation.
michael@0:   virtual void SetPrevContinuation(nsIFrame*) MOZ_OVERRIDE;
michael@0:   virtual void SetNextContinuation(nsIFrame*) MOZ_OVERRIDE;
michael@0: 
michael@0:   // Get the first/last continuation for this frame.
michael@0:   virtual nsIFrame* FirstContinuation() const MOZ_OVERRIDE;
michael@0:   virtual nsIFrame* LastContinuation() const MOZ_OVERRIDE;
michael@0: 
michael@0: #ifdef DEBUG
michael@0:   // Can aFrame2 be reached from aFrame1 by following prev/next continuations?
michael@0:   static bool IsInPrevContinuationChain(nsIFrame* aFrame1, nsIFrame* aFrame2);
michael@0:   static bool IsInNextContinuationChain(nsIFrame* aFrame1, nsIFrame* aFrame2);
michael@0: #endif
michael@0:   
michael@0:   // Get the previous/next continuation, only if it is fluid (an "in-flow").
michael@0:   nsIFrame* GetPrevInFlow() const;
michael@0:   nsIFrame* GetNextInFlow() const;
michael@0: 
michael@0:   virtual nsIFrame* GetPrevInFlowVirtual() const MOZ_OVERRIDE { return GetPrevInFlow(); }
michael@0:   virtual nsIFrame* GetNextInFlowVirtual() const MOZ_OVERRIDE { return GetNextInFlow(); }
michael@0:   
michael@0:   // Set a previous/next fluid continuation.
michael@0:   virtual void SetPrevInFlow(nsIFrame*) MOZ_OVERRIDE;
michael@0:   virtual void SetNextInFlow(nsIFrame*) MOZ_OVERRIDE;
michael@0: 
michael@0:   // Get the first/last frame in the current flow.
michael@0:   virtual nsIFrame* FirstInFlow() const MOZ_OVERRIDE;
michael@0:   virtual nsIFrame* LastInFlow() const MOZ_OVERRIDE;
michael@0: 
michael@0:   // Remove the frame from the flow. Connects the frame's prev-in-flow
michael@0:   // and its next-in-flow. This should only be called in frame Destroy() methods.
michael@0:   static void RemoveFromFlow(nsIFrame* aFrame);
michael@0: 
michael@0: protected:
michael@0:   nsSplittableFrame(nsStyleContext* aContext) : nsFrame(aContext) {}
michael@0: 
michael@0:   /**
michael@0:    * Determine the height consumed by our previous-in-flows.
michael@0:    *
michael@0:    * @note (bz) This makes laying out a splittable frame with N in-flows
michael@0:    *       O(N^2)! So, use this function with caution and minimize the number
michael@0:    *       of calls to this method.
michael@0:    */
michael@0:   nscoord GetConsumedHeight() const;
michael@0: 
michael@0:   /**
michael@0:    * Retrieve the effective computed height of this frame, which is the computed
michael@0:    * height, minus the height consumed by any previous in-flows.
michael@0:    */
michael@0:   nscoord GetEffectiveComputedHeight(const nsHTMLReflowState& aReflowState,
michael@0:                                      nscoord aConsumed = NS_INTRINSICSIZE) const;
michael@0: 
michael@0:   /**
michael@0:    * @see nsIFrame::GetLogicalSkipSides()
michael@0:    * @see nsIFrame::ApplyLogicalSkipSides()
michael@0:    */
michael@0:   virtual int GetLogicalSkipSides(const nsHTMLReflowState* aReflowState = nullptr) const MOZ_OVERRIDE;
michael@0: 
michael@0: #ifdef DEBUG
michael@0:   virtual void DumpBaseRegressionData(nsPresContext* aPresContext, FILE* out, int32_t aIndent) MOZ_OVERRIDE;
michael@0: #endif
michael@0: 
michael@0:   nsIFrame*   mPrevContinuation;
michael@0:   nsIFrame*   mNextContinuation;
michael@0: };
michael@0: 
michael@0: #endif /* nsSplittableFrame_h___ */