Repeat thead and tfoot when table contains page breaks.

This was already done in ariya#211
but somehow got lost when the Qt source tree was imported.

Note that I even improved this patch a bit to also properly repaint
the borders of cells in thead/tfoot.

http://code.google.com/p/phantomjs/issues/detail?id=615

src/qt/src/3rdparty/webkit/Source/WebCore/rendering/RenderTable.cpp

@@ -302,11 +302,20 @@ void RenderTable::layout()
 
     bool collapsing = collapseBorders();
 
+    // repeat header and footer on each page
+    int headHeight = 0;
+    int footHeight = 0;
     for (RenderObject* child = firstChild(); child; child = child->nextSibling()) {
         if (child->isTableSection()) {
             child->layoutIfNeeded();
             RenderTableSection* section = toRenderTableSection(child);
-            totalSectionLogicalHeight += section->calcRowLogicalHeight();
+            int rowHeight = section->calcRowLogicalHeight();
+            if (child == m_head) {
+                headHeight = rowHeight;
+            } else if (child == m_foot) {
+                footHeight = rowHeight;
+            }
+            totalSectionLogicalHeight += rowHeight;
             if (collapsing)
                 section->recalcOuterBorder();
             ASSERT(!section->needsLayout());
@@ -355,7 +364,7 @@ void RenderTable::layout()
     for (RenderObject* child = firstChild(); child; child = child->nextSibling()) {
         if (child->isTableSection())
             // FIXME: Distribute extra height between all table body sections instead of giving it all to the first one.
-            toRenderTableSection(child)->layoutRows(child == m_firstBody ? max(0, computedLogicalHeight - totalSectionLogicalHeight) : 0);
+            toRenderTableSection(child)->layoutRows(child == m_firstBody ? max(0, computedLogicalHeight - totalSectionLogicalHeight) : 0, headHeight, footHeight);
     }
 
     if (!m_firstBody && computedLogicalHeight > totalSectionLogicalHeight && !document()->inQuirksMode()) {
@@ -503,7 +512,59 @@ void RenderTable::paintObject(PaintInfo& paintInfo, int tx, int ty)
             child->paint(info, childPoint.x(), childPoint.y());
         }
     }
-
+
+    bool repaintedHead = false;
+    IntPoint repaintedHeadPoint;
+    bool repaintedFoot = false;
+    IntPoint repaintedFootPoint;
+    if (view()->pageLogicalHeight()) {
+        // re-paint header/footer if table is split over multiple pages
+        if (m_head) {
+            IntPoint childPoint = flipForWritingMode(m_head, IntPoint(tx, ty), ParentToChildFlippingAdjustment);
+            if (!info.rect.contains(childPoint.x() + m_head->x(), childPoint.y() + m_head->y())) {
+                repaintedHeadPoint = IntPoint(childPoint.x(), info.rect.y() - m_head->y());
+                repaintedHead = true;
+                dynamic_cast<RenderObject*>(m_head)->paint(info, repaintedHeadPoint.x(), repaintedHeadPoint.y());
+            }
+        }
+        if (m_foot) {
+            IntPoint childPoint = flipForWritingMode(m_foot, IntPoint(tx, ty), ParentToChildFlippingAdjustment);
+            if (!info.rect.contains(childPoint.x() + m_foot->x(), childPoint.y() + m_foot->y())) {
+                // find actual end of table on current page
+                int dy = 0;
+                const int max_dy = info.rect.y() + info.rect.height();
+                const int vspace = vBorderSpacing();
+                for (RenderObject* section = firstChild(); section; section = section->nextSibling()) {
+                    if (section->isTableSection()) {
+                        if (toRenderBox(section)->y() > max_dy) {
+                            continue;
+                        }
+                        int i = 0;
+                        for(RenderObject* row = section->firstChild(); row; row = row->nextSibling()) {
+                            if (!row->isTableRow()) {
+                                continue;
+                            }
+                            // get actual bottom-y position of this row - pretty complicated, how could this be simplified?
+                            // note how we have to take the rowPoint and section's y-offset into account, see e.g.
+                            // RenderTableSection::paint where this is also done...
+                            IntPoint rowPoint = flipForWritingMode(toRenderBox(row), IntPoint(tx, ty), ParentToChildFlippingAdjustment);
+                            int row_dy = rowPoint.y() + toRenderBox(row)->y() + toRenderBox(row)->logicalHeight() + toRenderBox(section)->y();
+                            if (row_dy < max_dy && row_dy > dy) {
+                                dy = row_dy;
+                            } else if (row_dy > max_dy) {
+                                break;
+                            }
+                            i++;
+                        }
+                    }
+                }
+                repaintedFoot = true;
+                repaintedFootPoint = IntPoint(childPoint.x(), dy - m_foot->y());
+                dynamic_cast<RenderObject*>(m_foot)->paint(info, repaintedFootPoint.x(), repaintedFootPoint.y());
+            }
+        }
+    }
+
     if (collapseBorders() && paintPhase == PaintPhaseChildBlockBackground && style()->visibility() == VISIBLE) {
         // Collect all the unique border styles that we want to paint in a sorted list.  Once we
         // have all the styles sorted, we then do individual passes, painting each style of border
@@ -522,6 +583,12 @@ void RenderTable::paintObject(PaintInfo& paintInfo, int tx, int ty)
             for (RenderObject* child = firstChild(); child; child = child->nextSibling())
                 if (child->isTableSection()) {
                     IntPoint childPoint = flipForWritingMode(toRenderTableSection(child), IntPoint(tx, ty), ParentToChildFlippingAdjustment);
+                    // also repaint borders of header/footer if required
+                    if (child == m_head && repaintedHead) {
+                        childPoint = repaintedHeadPoint;
+                    } else if (child == m_foot && repaintedFoot) {
+                        childPoint = repaintedFootPoint;
+                    }
                     child->paint(info, childPoint.x(), childPoint.y());
                 }
         }

src/qt/src/3rdparty/webkit/Source/WebCore/rendering/RenderTableSection.cpp

@@ -414,7 +414,7 @@ void RenderTableSection::layout()
     setNeedsLayout(false);
 }
 
-int RenderTableSection::layoutRows(int toAdd)
+int RenderTableSection::layoutRows(int toAdd, int headHeight, int footHeight)
 {
 #ifndef NDEBUG
     setNeedsLayoutIsForbidden(true);
@@ -506,13 +506,13 @@ int RenderTableSection::layoutRows(int toAdd)
             logicalHeightsForPrinting[r] = childLogicalHeight;
             LayoutState* layoutState = view()->layoutState();
             const int pageLogicalHeight = layoutState->m_pageLogicalHeight;
-            if (childLogicalHeight < pageLogicalHeight) {
+            if (childLogicalHeight < pageLogicalHeight - footHeight) {
                 const IntSize delta = layoutState->m_layoutOffset - layoutState->m_pageOffset;
                 const int logicalOffset = m_rowPos[r] + pageOffset;
                 const int offset = isHorizontalWritingMode() ? delta.height() : delta.width();
                 const int remainingLogicalHeight = (pageLogicalHeight - (offset + logicalOffset) % pageLogicalHeight) % pageLogicalHeight;
-                if (remainingLogicalHeight < childLogicalHeight) {
-                    pageOffset += remainingLogicalHeight;
+                if (remainingLogicalHeight - footHeight < childLogicalHeight) {
+                    pageOffset += remainingLogicalHeight + headHeight;
                 }
             }
             m_rowPos[r] += pageOffset;

src/qt/src/3rdparty/webkit/Source/WebCore/rendering/RenderTableSection.h

@@ -49,7 +49,7 @@ class RenderTableSection : public RenderBox {
 
     void setCellLogicalWidths();
     int calcRowLogicalHeight();
-    int layoutRows(int logicalHeight);
+    int layoutRows(int logicalHeight, int headHeight, int footHeight);
 
     RenderTable* table() const { return toRenderTable(parent()); }