michael@0: /* vim: set shiftwidth=2 tabstop=8 autoindent cindent expandtab: */
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: /* Per-block-formatting-context manager of font size inflation for pan and zoom UI. */
michael@0: 
michael@0: #include "nsFontInflationData.h"
michael@0: #include "FramePropertyTable.h"
michael@0: #include "nsTextControlFrame.h"
michael@0: #include "nsListControlFrame.h"
michael@0: #include "nsComboboxControlFrame.h"
michael@0: #include "nsHTMLReflowState.h"
michael@0: #include "nsTextFrameUtils.h"
michael@0: 
michael@0: using namespace mozilla;
michael@0: using namespace mozilla::layout;
michael@0: 
michael@0: static void
michael@0: DestroyFontInflationData(void *aPropertyValue)
michael@0: {
michael@0:   delete static_cast<nsFontInflationData*>(aPropertyValue);
michael@0: }
michael@0: 
michael@0: NS_DECLARE_FRAME_PROPERTY(FontInflationDataProperty, DestroyFontInflationData)
michael@0: 
michael@0: /* static */ nsFontInflationData*
michael@0: nsFontInflationData::FindFontInflationDataFor(const nsIFrame *aFrame)
michael@0: {
michael@0:   // We have one set of font inflation data per block formatting context.
michael@0:   const nsIFrame *bfc = FlowRootFor(aFrame);
michael@0:   NS_ASSERTION(bfc->GetStateBits() & NS_FRAME_FONT_INFLATION_FLOW_ROOT,
michael@0:                "should have found a flow root");
michael@0: 
michael@0:   return static_cast<nsFontInflationData*>(
michael@0:              bfc->Properties().Get(FontInflationDataProperty()));
michael@0: }
michael@0: 
michael@0: /* static */ bool
michael@0: nsFontInflationData::UpdateFontInflationDataWidthFor(const nsHTMLReflowState& aReflowState)
michael@0: {
michael@0:   nsIFrame *bfc = aReflowState.frame;
michael@0:   NS_ASSERTION(bfc->GetStateBits() & NS_FRAME_FONT_INFLATION_FLOW_ROOT,
michael@0:                "should have been given a flow root");
michael@0:   FrameProperties bfcProps(bfc->Properties());
michael@0:   nsFontInflationData *data = static_cast<nsFontInflationData*>(
michael@0:                                 bfcProps.Get(FontInflationDataProperty()));
michael@0:   bool oldInflationEnabled;
michael@0:   nscoord oldNCAWidth;
michael@0:   if (data) {
michael@0:     oldNCAWidth = data->mNCAWidth;
michael@0:     oldInflationEnabled = data->mInflationEnabled;
michael@0:   } else {
michael@0:     data = new nsFontInflationData(bfc);
michael@0:     bfcProps.Set(FontInflationDataProperty(), data);
michael@0:     oldNCAWidth = -1;
michael@0:     oldInflationEnabled = true; /* not relevant */
michael@0:   }
michael@0: 
michael@0:   data->UpdateWidth(aReflowState);
michael@0: 
michael@0:   if (oldInflationEnabled != data->mInflationEnabled)
michael@0:     return true;
michael@0: 
michael@0:   return oldInflationEnabled &&
michael@0:          oldNCAWidth != data->mNCAWidth;
michael@0: }
michael@0: 
michael@0: /* static */ void
michael@0: nsFontInflationData::MarkFontInflationDataTextDirty(nsIFrame *aBFCFrame)
michael@0: {
michael@0:   NS_ASSERTION(aBFCFrame->GetStateBits() & NS_FRAME_FONT_INFLATION_FLOW_ROOT,
michael@0:                "should have been given a flow root");
michael@0: 
michael@0:   FrameProperties bfcProps(aBFCFrame->Properties());
michael@0:   nsFontInflationData *data = static_cast<nsFontInflationData*>(
michael@0:                                 bfcProps.Get(FontInflationDataProperty()));
michael@0:   if (data) {
michael@0:     data->MarkTextDirty();
michael@0:   }
michael@0: }
michael@0: 
michael@0: nsFontInflationData::nsFontInflationData(nsIFrame *aBFCFrame)
michael@0:   : mBFCFrame(aBFCFrame)
michael@0:   , mNCAWidth(0)
michael@0:   , mTextAmount(0)
michael@0:   , mTextThreshold(0)
michael@0:   , mInflationEnabled(false)
michael@0:   , mTextDirty(true)
michael@0: {
michael@0: }
michael@0: 
michael@0: /**
michael@0:  * Find the closest common ancestor between aFrame1 and aFrame2, except
michael@0:  * treating the parent of a frame as the first-in-flow of its parent (so
michael@0:  * the result doesn't change when breaking changes).
michael@0:  *
michael@0:  * aKnownCommonAncestor is a known common ancestor of both.
michael@0:  */
michael@0: static nsIFrame*
michael@0: NearestCommonAncestorFirstInFlow(nsIFrame *aFrame1, nsIFrame *aFrame2,
michael@0:                                  nsIFrame *aKnownCommonAncestor)
michael@0: {
michael@0:   aFrame1 = aFrame1->FirstInFlow();
michael@0:   aFrame2 = aFrame2->FirstInFlow();
michael@0:   aKnownCommonAncestor = aKnownCommonAncestor->FirstInFlow();
michael@0: 
michael@0:   nsAutoTArray<nsIFrame*, 32> ancestors1, ancestors2;
michael@0:   for (nsIFrame *f = aFrame1; f != aKnownCommonAncestor;
michael@0:        (f = f->GetParent()) && (f = f->FirstInFlow())) {
michael@0:     ancestors1.AppendElement(f);
michael@0:   }
michael@0:   for (nsIFrame *f = aFrame2; f != aKnownCommonAncestor;
michael@0:        (f = f->GetParent()) && (f = f->FirstInFlow())) {
michael@0:     ancestors2.AppendElement(f);
michael@0:   }
michael@0: 
michael@0:   nsIFrame *result = aKnownCommonAncestor;
michael@0:   uint32_t i1 = ancestors1.Length(),
michael@0:            i2 = ancestors2.Length();
michael@0:   while (i1-- != 0 && i2-- != 0) {
michael@0:     if (ancestors1[i1] != ancestors2[i2]) {
michael@0:       break;
michael@0:     }
michael@0:     result = ancestors1[i1];
michael@0:   }
michael@0: 
michael@0:   return result;
michael@0: }
michael@0: 
michael@0: static nscoord
michael@0: ComputeDescendantWidth(const nsHTMLReflowState& aAncestorReflowState,
michael@0:                        nsIFrame *aDescendantFrame)
michael@0: {
michael@0:   nsIFrame *ancestorFrame = aAncestorReflowState.frame->FirstInFlow();
michael@0:   if (aDescendantFrame == ancestorFrame) {
michael@0:     return aAncestorReflowState.ComputedWidth();
michael@0:   }
michael@0: 
michael@0:   AutoInfallibleTArray<nsIFrame*, 16> frames;
michael@0:   for (nsIFrame *f = aDescendantFrame; f != ancestorFrame;
michael@0:        f = f->GetParent()->FirstInFlow()) {
michael@0:     frames.AppendElement(f);
michael@0:   }
michael@0: 
michael@0:   // This ignores the width contributions made by scrollbars, though in
michael@0:   // reality we don't have any scrollbars on the sorts of devices on
michael@0:   // which we use font inflation, so it's not a problem.  But it may
michael@0:   // occasionally cause problems when writing tests on desktop.
michael@0: 
michael@0:   uint32_t len = frames.Length();
michael@0:   nsHTMLReflowState *reflowStates = static_cast<nsHTMLReflowState*>
michael@0:                                 (moz_xmalloc(sizeof(nsHTMLReflowState) * len));
michael@0:   nsPresContext *presContext = aDescendantFrame->PresContext();
michael@0:   for (uint32_t i = 0; i < len; ++i) {
michael@0:     const nsHTMLReflowState &parentReflowState =
michael@0:       (i == 0) ? aAncestorReflowState : reflowStates[i - 1];
michael@0:     nsSize availSize(parentReflowState.ComputedWidth(), NS_UNCONSTRAINEDSIZE);
michael@0:     nsIFrame *frame = frames[len - i - 1];
michael@0:     NS_ABORT_IF_FALSE(frame->GetParent()->FirstInFlow() ==
michael@0:                         parentReflowState.frame->FirstInFlow(),
michael@0:                       "bad logic in this function");
michael@0:     new (reflowStates + i) nsHTMLReflowState(presContext, parentReflowState,
michael@0:                                              frame, availSize);
michael@0:   }
michael@0: 
michael@0:   NS_ABORT_IF_FALSE(reflowStates[len - 1].frame == aDescendantFrame,
michael@0:                     "bad logic in this function");
michael@0:   nscoord result = reflowStates[len - 1].ComputedWidth();
michael@0: 
michael@0:   for (uint32_t i = len; i-- != 0; ) {
michael@0:     reflowStates[i].~nsHTMLReflowState();
michael@0:   }
michael@0:   moz_free(reflowStates);
michael@0: 
michael@0:   return result;
michael@0: }
michael@0: 
michael@0: void
michael@0: nsFontInflationData::UpdateWidth(const nsHTMLReflowState &aReflowState)
michael@0: {
michael@0:   nsIFrame *bfc = aReflowState.frame;
michael@0:   NS_ASSERTION(bfc->GetStateBits() & NS_FRAME_FONT_INFLATION_FLOW_ROOT,
michael@0:                "must be block formatting context");
michael@0: 
michael@0:   nsIFrame *firstInflatableDescendant =
michael@0:              FindEdgeInflatableFrameIn(bfc, eFromStart);
michael@0:   if (!firstInflatableDescendant) {
michael@0:     mTextAmount = 0;
michael@0:     mTextThreshold = 0; // doesn't matter
michael@0:     mTextDirty = false;
michael@0:     mInflationEnabled = false;
michael@0:     return;
michael@0:   }
michael@0:   nsIFrame *lastInflatableDescendant =
michael@0:              FindEdgeInflatableFrameIn(bfc, eFromEnd);
michael@0:   NS_ABORT_IF_FALSE(!firstInflatableDescendant == !lastInflatableDescendant,
michael@0:                     "null-ness should match; NearestCommonAncestorFirstInFlow"
michael@0:                     " will crash when passed null");
michael@0: 
michael@0:   // Particularly when we're computing for the root BFC, the width of
michael@0:   // nca might differ significantly for the width of bfc.
michael@0:   nsIFrame *nca = NearestCommonAncestorFirstInFlow(firstInflatableDescendant,
michael@0:                                                    lastInflatableDescendant,
michael@0:                                                    bfc);
michael@0:   while (!nca->IsContainerForFontSizeInflation()) {
michael@0:     nca = nca->GetParent()->FirstInFlow();
michael@0:   }
michael@0: 
michael@0:   nscoord newNCAWidth = ComputeDescendantWidth(aReflowState, nca);
michael@0: 
michael@0:   // See comment above "font.size.inflation.lineThreshold" in
michael@0:   // modules/libpref/src/init/all.js .
michael@0:   nsIPresShell* presShell = bfc->PresContext()->PresShell();
michael@0:   uint32_t lineThreshold = presShell->FontSizeInflationLineThreshold();
michael@0:   nscoord newTextThreshold = (newNCAWidth * lineThreshold) / 100;
michael@0: 
michael@0:   if (mTextThreshold <= mTextAmount && mTextAmount < newTextThreshold) {
michael@0:     // Because we truncate our scan when we hit sufficient text, we now
michael@0:     // need to rescan.
michael@0:     mTextDirty = true;
michael@0:   }
michael@0: 
michael@0:   mNCAWidth = newNCAWidth;
michael@0:   mTextThreshold = newTextThreshold;
michael@0:   mInflationEnabled = mTextAmount >= mTextThreshold;
michael@0: }
michael@0: 
michael@0: /* static */ nsIFrame*
michael@0: nsFontInflationData::FindEdgeInflatableFrameIn(nsIFrame* aFrame,
michael@0:                                                SearchDirection aDirection)
michael@0: {
michael@0:   // NOTE: This function has a similar structure to ScanTextIn!
michael@0: 
michael@0:   // FIXME: Should probably only scan the text that's actually going to
michael@0:   // be inflated!
michael@0: 
michael@0:   nsIFormControlFrame* fcf = do_QueryFrame(aFrame);
michael@0:   if (fcf) {
michael@0:     return aFrame;
michael@0:   }
michael@0: 
michael@0:   // FIXME: aDirection!
michael@0:   nsAutoTArray<FrameChildList, 4> lists;
michael@0:   aFrame->GetChildLists(&lists);
michael@0:   for (uint32_t i = 0, len = lists.Length(); i < len; ++i) {
michael@0:     const nsFrameList& list =
michael@0:       lists[(aDirection == eFromStart) ? i : len - i - 1].mList;
michael@0:     for (nsIFrame *kid = (aDirection == eFromStart) ? list.FirstChild()
michael@0:                                                     : list.LastChild();
michael@0:          kid;
michael@0:          kid = (aDirection == eFromStart) ? kid->GetNextSibling()
michael@0:                                           : kid->GetPrevSibling()) {
michael@0:       if (kid->GetStateBits() & NS_FRAME_FONT_INFLATION_FLOW_ROOT) {
michael@0:         // Goes in a different set of inflation data.
michael@0:         continue;
michael@0:       }
michael@0: 
michael@0:       if (kid->GetType() == nsGkAtoms::textFrame) {
michael@0:         nsIContent *content = kid->GetContent();
michael@0:         if (content && kid == content->GetPrimaryFrame()) {
michael@0:           uint32_t len = nsTextFrameUtils::
michael@0:             ComputeApproximateLengthWithWhitespaceCompression(
michael@0:               content, kid->StyleText());
michael@0:           if (len != 0) {
michael@0:             return kid;
michael@0:           }
michael@0:         }
michael@0:       } else {
michael@0:         nsIFrame *kidResult =
michael@0:           FindEdgeInflatableFrameIn(kid, aDirection);
michael@0:         if (kidResult) {
michael@0:           return kidResult;
michael@0:         }
michael@0:       }
michael@0:     }
michael@0:   }
michael@0: 
michael@0:   return nullptr;
michael@0: }
michael@0: 
michael@0: void
michael@0: nsFontInflationData::ScanText()
michael@0: {
michael@0:   mTextDirty = false;
michael@0:   mTextAmount = 0;
michael@0:   ScanTextIn(mBFCFrame);
michael@0:   mInflationEnabled = mTextAmount >= mTextThreshold;
michael@0: }
michael@0: 
michael@0: static uint32_t
michael@0: DoCharCountOfLargestOption(nsIFrame *aContainer)
michael@0: {
michael@0:   uint32_t result = 0;
michael@0:   for (nsIFrame* option = aContainer->GetFirstPrincipalChild();
michael@0:        option; option = option->GetNextSibling()) {
michael@0:     uint32_t optionResult;
michael@0:     if (option->GetContent()->IsHTML(nsGkAtoms::optgroup)) {
michael@0:       optionResult = DoCharCountOfLargestOption(option);
michael@0:     } else {
michael@0:       // REVIEW: Check the frame structure for this!
michael@0:       optionResult = 0;
michael@0:       for (nsIFrame *optionChild = option->GetFirstPrincipalChild();
michael@0:            optionChild; optionChild = optionChild->GetNextSibling()) {
michael@0:         if (optionChild->GetType() == nsGkAtoms::textFrame) {
michael@0:           optionResult += nsTextFrameUtils::
michael@0:             ComputeApproximateLengthWithWhitespaceCompression(
michael@0:               optionChild->GetContent(), optionChild->StyleText());
michael@0:         }
michael@0:       }
michael@0:     }
michael@0:     if (optionResult > result) {
michael@0:       result = optionResult;
michael@0:     }
michael@0:   }
michael@0:   return result;
michael@0: }
michael@0: 
michael@0: static uint32_t
michael@0: CharCountOfLargestOption(nsIFrame *aListControlFrame)
michael@0: {
michael@0:   return DoCharCountOfLargestOption(
michael@0:     static_cast<nsListControlFrame*>(aListControlFrame)->GetOptionsContainer());
michael@0: }
michael@0: 
michael@0: void
michael@0: nsFontInflationData::ScanTextIn(nsIFrame *aFrame)
michael@0: {
michael@0:   // NOTE: This function has a similar structure to FindEdgeInflatableFrameIn!
michael@0: 
michael@0:   // FIXME: Should probably only scan the text that's actually going to
michael@0:   // be inflated!
michael@0: 
michael@0:   nsIFrame::ChildListIterator lists(aFrame);
michael@0:   for (; !lists.IsDone(); lists.Next()) {
michael@0:     nsFrameList::Enumerator kids(lists.CurrentList());
michael@0:     for (; !kids.AtEnd(); kids.Next()) {
michael@0:       nsIFrame *kid = kids.get();
michael@0:       if (kid->GetStateBits() & NS_FRAME_FONT_INFLATION_FLOW_ROOT) {
michael@0:         // Goes in a different set of inflation data.
michael@0:         continue;
michael@0:       }
michael@0: 
michael@0:       nsIAtom *fType = kid->GetType();
michael@0:       if (fType == nsGkAtoms::textFrame) {
michael@0:         nsIContent *content = kid->GetContent();
michael@0:         if (content && kid == content->GetPrimaryFrame()) {
michael@0:           uint32_t len = nsTextFrameUtils::
michael@0:             ComputeApproximateLengthWithWhitespaceCompression(
michael@0:               content, kid->StyleText());
michael@0:           if (len != 0) {
michael@0:             nscoord fontSize = kid->StyleFont()->mFont.size;
michael@0:             if (fontSize > 0) {
michael@0:               mTextAmount += fontSize * len;
michael@0:             }
michael@0:           }
michael@0:         }
michael@0:       } else if (fType == nsGkAtoms::textInputFrame) {
michael@0:         // We don't want changes to the amount of text in a text input
michael@0:         // to change what we count towards inflation.
michael@0:         nscoord fontSize = kid->StyleFont()->mFont.size;
michael@0:         int32_t charCount = static_cast<nsTextControlFrame*>(kid)->GetCols();
michael@0:         mTextAmount += charCount * fontSize;
michael@0:       } else if (fType == nsGkAtoms::comboboxControlFrame) {
michael@0:         // See textInputFrame above (with s/amount of text/selected option/).
michael@0:         // Don't just recurse down to the list control inside, since we
michael@0:         // need to exclude the display frame.
michael@0:         nscoord fontSize = kid->StyleFont()->mFont.size;
michael@0:         int32_t charCount = CharCountOfLargestOption(
michael@0:           static_cast<nsComboboxControlFrame*>(kid)->GetDropDown());
michael@0:         mTextAmount += charCount * fontSize;
michael@0:       } else if (fType == nsGkAtoms::listControlFrame) {
michael@0:         // See textInputFrame above (with s/amount of text/selected option/).
michael@0:         nscoord fontSize = kid->StyleFont()->mFont.size;
michael@0:         int32_t charCount = CharCountOfLargestOption(kid);
michael@0:         mTextAmount += charCount * fontSize;
michael@0:       } else {
michael@0:         // recursive step
michael@0:         ScanTextIn(kid);
michael@0:       }
michael@0: 
michael@0:       if (mTextAmount >= mTextThreshold) {
michael@0:         return;
michael@0:       }
michael@0:     }
michael@0:   }
michael@0: }