[UnifiedPDF] Describe selection rects in terms of PDFPageCoverage

https://bugs.webkit.org/show_bug.cgi?id=274139
rdar://128043619

Reviewed by Abrar Rahman Protyasha.

Replace `UnifiedPDFPlugin::boundsForSelection()` with `UnifiedPDFPlugin::pageCoverageForSelection()`
which returns a `PDFPageCoverage`, which will be useful in future when we need to have per-page
selection bounds info.

`UnifiedPDFPlugin::textIndicatorForSelection()` can use this, asking for only the first page.
`UnifiedPDFPlugin::selectionBoundsForFirstPageInDocumentSpace()` can be removed.

* Source/WebKit/WebProcess/Plugins/PDF/UnifiedPDF/UnifiedPDFPlugin.h:
* Source/WebKit/WebProcess/Plugins/PDF/UnifiedPDF/UnifiedPDFPlugin.mm:
(WebKit::UnifiedPDFPlugin::pageCoverageForSelection const):
(WebKit::UnifiedPDFPlugin::boundsForSelection const):
(WebKit::UnifiedPDFPlugin::repaintOnSelectionActiveStateChangeIfNeeded):
(WebKit::UnifiedPDFPlugin::setCurrentSelection):
(WebKit::UnifiedPDFPlugin::textIndicatorForSelection):
(WebKit::UnifiedPDFPlugin::selectionBoundsForFirstPageInDocumentSpace const): Deleted.

Canonical link: https://commits.webkit.org/278759@main

Source/WebKit/WebProcess/Plugins/PDF/UnifiedPDF/UnifiedPDFPlugin.h

@@ -184,8 +184,6 @@ class UnifiedPDFPlugin final : public PDFPluginBase, public WebCore::GraphicsLay
         Plugin
     };
 
-    Vector<WebCore::FloatRect> boundsForSelection(const PDFSelection *, CoordinateSpace inSpace) const;
-
     RetainPtr<PDFPage> pageAtIndex(PDFDocumentLayout::PageIndex) const;
 
     void setPDFDisplayModeForTesting(const String&) final;
@@ -391,8 +389,14 @@ class UnifiedPDFPlugin final : public PDFPluginBase, public WebCore::GraphicsLay
 
     RefPtr<WebCore::TextIndicator> textIndicatorForCurrentSelection(OptionSet<WebCore::TextIndicatorOption>, WebCore::TextIndicatorPresentationTransition) final;
     RefPtr<WebCore::TextIndicator> textIndicatorForSelection(PDFSelection *, OptionSet<WebCore::TextIndicatorOption>, WebCore::TextIndicatorPresentationTransition);
+
     bool performDictionaryLookupAtLocation(const WebCore::FloatPoint&) override;
-    std::optional<WebCore::FloatRect> selectionBoundsForFirstPageInDocumentSpace(const RetainPtr<PDFSelection>&) const;
+
+    enum class FirstPageOnly : bool { No, Yes };
+    PDFPageCoverage pageCoverageForSelection(PDFSelection *, FirstPageOnly = FirstPageOnly::No) const;
+
+    Vector<WebCore::FloatRect> boundsForSelection(PDFSelection *, CoordinateSpace) const;
+
     bool showDefinitionForSelection(PDFSelection *);
     std::pair<String, RetainPtr<PDFSelection>> textForImmediateActionHitTestAtPoint(const WebCore::FloatPoint&, WebHitTestResultData&) override;
     WebCore::DictionaryPopupInfo dictionaryPopupInfoForSelection(PDFSelection *, WebCore::TextIndicatorPresentationTransition) override;

Source/WebKit/WebProcess/Plugins/PDF/UnifiedPDF/UnifiedPDFPlugin.mm

@@ -3284,17 +3284,39 @@ static FloatRect computeMarqueeSelectionRect(const WebCore::FloatPoint& point1,
     unfreezeCursorAfterSelectionDragIfNeeded();
 }
 
-Vector<FloatRect> UnifiedPDFPlugin::boundsForSelection(const PDFSelection *selection, CoordinateSpace inSpace) const
+PDFPageCoverage UnifiedPDFPlugin::pageCoverageForSelection(PDFSelection *selection, FirstPageOnly firstPageOnly) const
 {
     if (!selection || [selection isEmpty])
         return { };
 
-    return makeVector([selection pages], [this, selection, inSpace](PDFPage *page) -> std::optional<FloatRect> {
+    auto pageCoverage = PDFPageCoverage { };
+
+    for (PDFPage *page in [selection pages]) {
         auto pageIndex = m_documentLayout.indexForPage(page);
         if (!pageIndex)
-            return { };
-        return convertUp(CoordinateSpace::PDFPage, inSpace, FloatRect { [selection boundsForPage:page] }, *pageIndex);
-    });
+            continue;
+
+        pageCoverage.append({ *pageIndex, FloatRect { [selection boundsForPage:page] } });
+        if (firstPageOnly == FirstPageOnly::Yes)
+            break;
+    }
+
+    return pageCoverage;
+}
+
+Vector<FloatRect> UnifiedPDFPlugin::boundsForSelection(PDFSelection *selection, CoordinateSpace targetSpace) const
+{
+    auto pageCoverage = pageCoverageForSelection(selection);
+    if (pageCoverage.isEmpty())
+        return { };
+
+    Vector<FloatRect> pageRects;
+    pageRects.reserveInitialCapacity(pageCoverage.size());
+
+    for (auto& page : pageCoverage)
+        pageRects.append(convertUp(CoordinateSpace::PDFPage, targetSpace, page.pageBounds, page.pageIndex));
+
+    return pageRects;
 }
 
 void UnifiedPDFPlugin::repaintOnSelectionActiveStateChangeIfNeeded(ActiveStateChangeReason reason, const Vector<FloatRect>& additionalDocumentRectsToRepaint)
@@ -3312,7 +3334,6 @@ static FloatRect computeMarqueeSelectionRect(const WebCore::FloatPoint& point1,
 
     auto selectionDocumentRectsToRepaint = boundsForSelection(protectedCurrentSelection().get(), CoordinateSpace::PDFDocumentLayout);
     selectionDocumentRectsToRepaint.appendVector(additionalDocumentRectsToRepaint);
-
     setNeedsRepaintInDocumentRects(RepaintRequirement::Selection, selectionDocumentRectsToRepaint);
 }
 
@@ -3323,12 +3344,12 @@ static FloatRect computeMarqueeSelectionRect(const WebCore::FloatPoint& point1,
 
 void UnifiedPDFPlugin::setCurrentSelection(RetainPtr<PDFSelection>&& selection)
 {
-    auto staleSelectionDocumentRectsToRepaint = boundsForSelection(protectedCurrentSelection().get(), CoordinateSpace::PDFDocumentLayout);
+    auto previousSelectionDocumentRectsToRepaint = boundsForSelection(protectedCurrentSelection().get(), CoordinateSpace::PDFDocumentLayout);
 
     m_currentSelection = WTFMove(selection);
     // FIXME: <https://webkit.org/b/268980> Selection painting requests should be only be made if the current selection has changed.
     // FIXME: <https://webkit.org/b/270070> Selection painting should be optimized by only repainting diff between old and new selection.
-    repaintOnSelectionActiveStateChangeIfNeeded(ActiveStateChangeReason::SetCurrentSelection, staleSelectionDocumentRectsToRepaint);
+    repaintOnSelectionActiveStateChangeIfNeeded(ActiveStateChangeReason::SetCurrentSelection, previousSelectionDocumentRectsToRepaint);
     notifySelectionChanged();
 }
 
@@ -3574,12 +3595,11 @@ static NSStringCompareOptions compareOptionsForFindOptions(WebCore::FindOptions
 
 RefPtr<TextIndicator> UnifiedPDFPlugin::textIndicatorForSelection(PDFSelection *selection, OptionSet<WebCore::TextIndicatorOption> options, WebCore::TextIndicatorPresentationTransition transition)
 {
-    auto selectionBounds = selectionBoundsForFirstPageInDocumentSpace(selection);
-    if (!selectionBounds)
+    auto selectionPageCoverage = pageCoverageForSelection(selection, FirstPageOnly::Yes);
+    if (selectionPageCoverage.isEmpty())
         return nullptr;
 
-    auto rectInDocumentCoordinates = *selectionBounds;
-    auto rectInContentsCoordinates = convertUp(CoordinateSpace::PDFDocumentLayout, CoordinateSpace::Contents, rectInDocumentCoordinates);
+    auto rectInContentsCoordinates = convertUp(CoordinateSpace::PDFPage, CoordinateSpace::Contents, selectionPageCoverage[0].pageBounds, selectionPageCoverage[0].pageIndex);
     auto rectInPluginCoordinates = convertUp(CoordinateSpace::Contents, CoordinateSpace::Plugin, rectInContentsCoordinates);
     auto rectInRootViewCoordinates = convertFromPluginToRootView(enclosingIntRect(rectInPluginCoordinates));
 
@@ -3636,22 +3656,6 @@ static NSStringCompareOptions compareOptionsForFindOptions(WebCore::FindOptions
     return showDefinitionForSelection(lookupSelection.get());
 }
 
-std::optional<FloatRect> UnifiedPDFPlugin::selectionBoundsForFirstPageInDocumentSpace(const RetainPtr<PDFSelection>& selection) const
-{
-    if (!selection)
-        return { };
-
-    for (PDFPage *page in [selection pages]) {
-        auto pageIndex = m_documentLayout.indexForPage(page);
-        if (!pageIndex)
-            continue;
-        auto rectForPage = FloatRect { [selection boundsForPage:page] };
-        return convertUp(CoordinateSpace::PDFPage, CoordinateSpace::PDFDocumentLayout, rectForPage, *pageIndex);
-    }
-
-    return { };
-}
-
 WebCore::DictionaryPopupInfo UnifiedPDFPlugin::dictionaryPopupInfoForSelection(PDFSelection *selection, WebCore::TextIndicatorPresentationTransition transition)
 {
     DictionaryPopupInfo dictionaryPopupInfo = PDFPluginBase::dictionaryPopupInfoForSelection(selection, transition);