[UnifiedPDF] Get initial painting working

https://bugs.webkit.org/show_bug.cgi?id=262311
rdar://116185973

Reviewed by Tim Horton.

Start getting PDF drawing working for Unified PDF. Currently this just draws the first
page via `CGPDFDocumentCreateWithProvider()` and `CGPDFDocumentGetPage()`.

Move two bits of code into PDFPluginBase; first, have it handle `geometryDidChange()` so
we can store the size. Second, because UnifiedPDFPlugin isn't layer-backed, we need to
plumb through a `paint()` function from `PluginView`.

* Source/WebKit/WebProcess/Plugins/PDF/PDFPlugin.h:
* Source/WebKit/WebProcess/Plugins/PDF/PDFPlugin.mm:
(WebKit::PDFPlugin::geometryDidChange):
* Source/WebKit/WebProcess/Plugins/PDF/PDFPluginBase.h:
(WebKit::PDFPluginBase::paint):
(WebKit::PDFPluginBase::size const):
(WebKit::PDFPluginBase::geometryDidChange): Deleted.
* Source/WebKit/WebProcess/Plugins/PDF/PDFPluginBase.mm:
(WebKit::PDFPluginBase::geometryDidChange):
* Source/WebKit/WebProcess/Plugins/PDF/UnifiedPDF/UnifiedPDFPlugin.h:
* Source/WebKit/WebProcess/Plugins/PDF/UnifiedPDF/UnifiedPDFPlugin.mm:
(WebKit::UnifiedPDFPlugin::createPDFDocument):
(WebKit::UnifiedPDFPlugin::installPDFDocument):
(WebKit::UnifiedPDFPlugin::paint):
(WebKit::UnifiedPDFPlugin::geometryDidChange):
* Source/WebKit/WebProcess/Plugins/PluginView.cpp:
(WebKit::PluginView::paint):

Canonical link: https://commits.webkit.org/268610@main

Source/WebKit/WebProcess/Plugins/PDF/PDFPlugin.h

@@ -95,8 +95,6 @@ class PDFPlugin final : public PDFPluginBase, public WebCore::ScrollableArea {
 
     static WebCore::PluginInfo pluginInfo();
 
-    WebCore::IntSize size() const { return m_size; }
-
     void didMutatePDFDocument() { m_pdfDocumentWasMutated = true; }
 
     void paintControlForLayerInContext(CALayer *, CGContextRef);
@@ -301,8 +299,6 @@ class PDFPlugin final : public PDFPluginBase, public WebCore::ScrollableArea {
 
     RetainPtr<WKPDFLayerControllerDelegate> m_pdfLayerControllerDelegate;
 
-    WebCore::IntSize m_size;
-
     URL m_sourceURL;
 
     RetainPtr<PDFDocument> m_pdfDocument;

Source/WebKit/WebProcess/Plugins/PDF/PDFPlugin.mm

@@ -2008,7 +2008,8 @@ static void jsPDFDocFinalize(JSObjectRef object)
     if (size() == pluginSize && m_view->pageScaleFactor() == [m_pdfLayerController contentScaleFactor])
         return;
 
-    m_size = pluginSize;
+    PDFPluginBase::geometryDidChange(pluginSize, pluginToRootViewTransform);
+
     m_rootViewToPluginTransform = valueOrDefault(pluginToRootViewTransform.inverse());
     [m_pdfLayerController setFrameSize:pluginSize];
 

Source/WebKit/WebProcess/Plugins/PDF/PDFPluginBase.h

@@ -76,13 +76,15 @@ class PDFPluginBase : public ThreadSafeRefCounted<PDFPluginBase> {
 
     virtual bool isComposited() const { return false; }
 
+    virtual void paint(WebCore::GraphicsContext&, const WebCore::IntRect&) { }
+
     virtual CGFloat scaleFactor() const = 0;
 
     // FIXME: Can we use PDFDocument here?
     virtual RetainPtr<PDFDocument> pdfDocumentForPrinting() const = 0;
     virtual WebCore::FloatSize pdfDocumentSizeForPrinting() const = 0;
 
-    virtual void geometryDidChange(const WebCore::IntSize& pluginSize, const WebCore::AffineTransform& pluginToRootViewTransform) { }
+    virtual void geometryDidChange(const WebCore::IntSize& pluginSize, const WebCore::AffineTransform& pluginToRootViewTransform);
     virtual void visibilityDidChange(bool) { }
     virtual void contentsScaleFactorChanged(float) { }
 
@@ -119,6 +121,7 @@ class PDFPluginBase : public ThreadSafeRefCounted<PDFPluginBase> {
     bool isBeingDestroyed() const { return m_isBeingDestroyed; }
 
     bool isFullFramePlugin() const;
+    WebCore::IntSize size() const { return m_size; }
 
     void streamDidReceiveResponse(const WebCore::ResourceResponse&);
     void streamDidReceiveData(const WebCore::SharedBuffer&);
@@ -149,6 +152,8 @@ class PDFPluginBase : public ThreadSafeRefCounted<PDFPluginBase> {
     String m_suggestedFilename;
     uint64_t m_streamedBytes { 0 };
 
+    WebCore::IntSize m_size;
+
     bool m_documentFinishedLoading { false };
     bool m_isBeingDestroyed { false };
     bool m_hasBeenDestroyed { false };

Source/WebKit/WebProcess/Plugins/PDF/PDFPluginBase.mm

@@ -148,6 +148,11 @@
     m_view->frame()->document()->loader()->addArchiveResource(resource.releaseNonNull());
 }
 
+void PDFPluginBase::geometryDidChange(const IntSize& pluginSize, const AffineTransform& pluginToRootViewTransform)
+{
+    m_size = pluginSize;
+}
+
 } // namespace WebKit
 
 #endif // ENABLE(PDFKIT_PLUGIN) || ENABLE(UNIFIED_PDF)

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

@@ -46,11 +46,15 @@ class UnifiedPDFPlugin final : public PDFPluginBase {
     void createPDFDocument() override;
     void installPDFDocument() override;
 
+    void paint(WebCore::GraphicsContext&, const WebCore::IntRect&) override;
+
     CGFloat scaleFactor() const override;
 
     RetainPtr<PDFDocument> pdfDocumentForPrinting() const override;
     WebCore::FloatSize pdfDocumentSizeForPrinting() const override;
 
+    void geometryDidChange(const WebCore::IntSize&, const WebCore::AffineTransform&) override;
+
     RefPtr<WebCore::FragmentedSharedBuffer> liveResourceData() const override;
 
     bool handleMouseEvent(const WebMouseEvent&) override;
@@ -75,6 +79,8 @@ class UnifiedPDFPlugin final : public PDFPluginBase {
     id accessibilityHitTest(const WebCore::IntPoint&) const override;
     id accessibilityObject() const override;
     id accessibilityAssociatedPluginParentForElement(WebCore::Element*) const override;
+
+    RetainPtr<CGPDFDocumentRef> m_pdfDocument;
 };
 
 } // namespace WebKit

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

@@ -28,6 +28,9 @@
 
 #if ENABLE(UNIFIED_PDF)
 
+#include <CoreGraphics/CoreGraphics.h>
+#include <WebCore/GraphicsContext.h>
+#include <WebCore/ImageBuffer.h>
 
 namespace WebKit {
 using namespace WebCore;
@@ -49,19 +52,66 @@
 
 void UnifiedPDFPlugin::createPDFDocument()
 {
-
+    auto dataProvider = adoptCF(CGDataProviderCreateWithCFData(m_data.get()));
+    m_pdfDocument = adoptCF(CGPDFDocumentCreateWithProvider(dataProvider.get()));
 }
 
 void UnifiedPDFPlugin::installPDFDocument()
 {
+    ASSERT(isMainRunLoop());
+
+    if (m_hasBeenDestroyed)
+        return;
+
+    if (!m_pdfDocument)
+        return;
+
+    if (!m_view)
+        return;
+
+}
+
+void UnifiedPDFPlugin::paint(GraphicsContext& context, const WebCore::IntRect& rect)
+{
+    ALWAYS_LOG_WITH_STREAM(stream << "UnifiedPDFPlugin::paint " << rect);
+    ASSERT(!context.paintingDisabled());
+
+    if (m_size.isEmpty())
+        return;
 
+    auto imageBuffer = ImageBuffer::create(m_size, RenderingPurpose::Unspecified, 1.0, DestinationColorSpace::SRGB(), PixelFormat::BGRA8);
+    if (!imageBuffer)
+        return;
+
+    RetainPtr firstPage = CGPDFDocumentGetPage(m_pdfDocument.get(), 1);
+    if (!firstPage)
+        return;
+
+    CGContextRef cgContext = imageBuffer->context().platformContext();
+    CGRect pageCropBox = CGPDFPageGetBoxRect(firstPage.get(), kCGPDFCropBox);
+
+    CGRect clipRect = CGRectMake(0, 0, pageCropBox.size.width, pageCropBox.size.height);
+    CGContextAddRect(cgContext, clipRect);
+    CGContextClip(cgContext);
+
+    CGContextDrawPDFPage(cgContext, firstPage.get());
+
+    context.drawImageBuffer(*imageBuffer, FloatPoint { });
 }
 
 CGFloat UnifiedPDFPlugin::scaleFactor() const
 {
     return 1;
 }
 
+void UnifiedPDFPlugin::geometryDidChange(const IntSize& pluginSize, const AffineTransform& pluginToRootViewTransform)
+{
+    if (size() == pluginSize)
+        return;
+
+    PDFPluginBase::geometryDidChange(pluginSize, pluginToRootViewTransform);
+}
+
 RetainPtr<PDFDocument> UnifiedPDFPlugin::pdfDocumentForPrinting() const
 {
     return nil;

Source/WebKit/WebProcess/Plugins/PluginView.cpp

@@ -452,7 +452,7 @@ void PluginView::setFrameRect(const WebCore::IntRect& rect)
     viewGeometryDidChange();
 }
 
-void PluginView::paint(GraphicsContext& context, const IntRect& /*dirtyRect*/, Widget::SecurityOriginPaintPolicy, RegionContext*)
+void PluginView::paint(GraphicsContext& context, const IntRect& dirtyRect, Widget::SecurityOriginPaintPolicy, RegionContext*)
 {
     if (!m_isInitialized)
         return;
@@ -481,7 +481,10 @@ void PluginView::paint(GraphicsContext& context, const IntRect& /*dirtyRect*/, W
                 deviceScaleFactor = page->deviceScaleFactor();
             m_transientPaintingSnapshot->paint(context, deviceScaleFactor, frameRect().location(), m_transientPaintingSnapshot->bounds());
         }
+        return;
     }
+
+    m_plugin->paint(context, dirtyRect);
 }
 
 void PluginView::frameRectsChanged()