Copy the KDE 3.5 branch to branches/trinity for new KDE 3.5 features.

BUG:215923


git-svn-id: svn://anonsvn.kde.org/home/kde/branches/trinity/kdelibs@1054174 283d02a7-25f6-0310-bc7c-ecb5cbfe19da

1 files changed, 2664 insertions, 0 deletions

diff --git a/khtml/khtml_caret.cpp b/khtml/khtml_caret.cpp
new file mode 100644
index 000000000..55050beaa
--- /dev/null
+++ b/khtml/khtml_caret.cpp
@@ -0,0 +1,2664 @@
+/* This file is part of the KDE project
+ *
+ * Copyright (C) 2003-2004 Leo Savernik <l.savernik@aon.at>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Library General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Library General Public License for more details.
+ *
+ * You should have received a copy of the GNU Library General Public License
+ * along with this library; see the file COPYING.LIB.  If not, write to
+ * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
+ * Boston, MA 02110-1301, USA.
+ */
+
+
+#include "khtml_caret_p.h"
+
+#include "html/html_documentimpl.h"
+
+namespace khtml {
+
+/** Flags representing the type of advance that has been made.
+ * @param LeftObject a render object was left and an ascent to its parent has
+ *	taken place
+ * @param AdvancedToSibling an actual advance to a sibling has taken place
+ * @param EnteredObject a render object was entered by descending into it from
+ *	its parent object.
+ */
+enum ObjectAdvanceState {
+  LeftObject = 0x01, AdvancedToSibling = 0x02, EnteredObject = 0x04
+};
+
+/** All possible states that may occur during render object traversal.
+ * @param OutsideDescending outside of the current object, ready to descend
+ *	into children
+ * @param InsideDescending inside the current object, descending into
+ *	children
+ * @param InsideAscending inside the current object, ascending to parents
+ * @param OutsideAscending outsie the current object, ascending to parents
+ */
+enum ObjectTraversalState {
+  OutsideDescending, InsideDescending, InsideAscending, OutsideAscending
+};
+
+/** Traverses the render object tree in a fine granularity.
+ * @param obj render object
+ * @param trav object traversal state
+ * @param toBegin traverse towards beginning
+ * @param base base render object which this method must not advance beyond
+ *	(0 means document)
+ * @param state object advance state (enum ObjectAdvanceState)
+ * @return the render object according to the state. May be the same as \c obj
+ */
+static RenderObject* traverseRenderObjects(RenderObject *obj,
+		ObjectTraversalState &trav, bool toBegin, RenderObject *base,
+                int &state)
+{
+  RenderObject *r;
+  switch (trav) {
+    case OutsideDescending:
+      trav = InsideDescending;
+      break;
+    case InsideDescending:
+      r = toBegin ? obj->lastChild() : obj->firstChild();
+      if (r) {
+        trav = OutsideDescending;
+        obj = r;
+        state |= EnteredObject;
+      } else {
+        trav = InsideAscending;
+      }
+      break;
+    case InsideAscending:
+      trav = OutsideAscending;
+      break;
+    case OutsideAscending:
+      r = toBegin ? obj->previousSibling() : obj->nextSibling();
+      if (r) {
+        trav = OutsideDescending;
+        state |= AdvancedToSibling;
+      } else {
+        r = obj->parent();
+        if (r == base) r = 0;
+        trav = InsideAscending;
+        state |= LeftObject;
+      }
+      obj = r;
+      break;
+  }/*end switch*/
+
+  return obj;
+}
+
+/** Like RenderObject::objectBelow, but confined to stay within \c base.
+ * @param obj render object to begin with
+ * @param trav object traversal state, will be reset within this function
+ * @param base base render object (0: no base)
+ */
+static inline RenderObject *renderObjectBelow(RenderObject *obj, ObjectTraversalState &trav, RenderObject *base)
+{
+  trav = InsideDescending;
+  int state;		// we don't need the state, so we don't initialize it
+  RenderObject *r = obj;
+  while (r && trav != OutsideDescending) {
+    r = traverseRenderObjects(r, trav, false, base, state);
+#if DEBUG_CARETMODE > 3
+    kdDebug(6200) << "renderObjectBelow: r " << r << " trav " << trav << endl;
+#endif
+  }
+  trav = InsideDescending;
+  return r;
+}
+
+/** Like RenderObject::objectAbove, but confined to stay within \c base.
+ * @param obj render object to begin with
+ * @param trav object traversal state, will be reset within this function
+ * @param base base render object (0: no base)
+ */
+static inline RenderObject *renderObjectAbove(RenderObject *obj, ObjectTraversalState &trav, RenderObject *base)
+{
+  trav = OutsideAscending;
+  int state;		// we don't need the state, so we don't initialize it
+  RenderObject *r = obj;
+  while (r && trav != InsideAscending) {
+    r = traverseRenderObjects(r, trav, true, base, state);
+#if DEBUG_CARETMODE > 3
+    kdDebug(6200) << "renderObjectAbove: r " << r << " trav " << trav << endl;
+#endif
+  }
+  trav = InsideAscending;
+  return r;
+}
+
+/** Checks whether the given inline box matches the IndicatedFlows policy
+ * @param box inline box to test
+ * @return true on match
+ */
+static inline bool isIndicatedInlineBox(InlineBox *box)
+{
+  // text boxes are never indicated.
+  if (box->isInlineTextBox()) return false;
+  RenderStyle *s = box->object()->style();
+  return s->borderLeftWidth() || s->borderRightWidth()
+  	|| s->borderTopWidth() || s->borderBottomWidth()
+	|| s->paddingLeft().value() || s->paddingRight().value()
+	|| s->paddingTop().value() || s->paddingBottom().value()
+	// ### Can inline elements have top/bottom margins? Couldn't find
+	// it in the CSS 2 spec, but Mozilla ignores them, so we do, too.
+	|| s->marginLeft().value() || s->marginRight().value();
+}
+
+/** Checks whether the given render object matches the IndicatedFlows policy
+ * @param r render object to test
+ * @return true on match
+ */
+static inline bool isIndicatedFlow(RenderObject *r)
+{
+  RenderStyle *s = r->style();
+  return s->borderLeftStyle() != BNONE || s->borderRightStyle() != BNONE
+  	|| s->borderTopStyle() != BNONE || s->borderBottomStyle() != BNONE
+//	|| s->paddingLeft().value() || s->paddingRight().value()
+//	|| s->paddingTop().value() || s->paddingBottom().value()
+//	|| s->marginLeft().value() || s->marginRight().value()
+	|| s->hasClip() || s->hidesOverflow()
+	|| s->backgroundColor().isValid() || s->backgroundImage();
+}
+
+/** Advances to the next render object, taking into account the current
+ * traversal state.
+ *
+ * @param r render object
+ * @param trav object traversal state
+ * @param toBegin @p true, advance towards beginning, @p false, advance toward end
+ * @param base base render object which this method must not advance beyond
+ *	(0 means document)
+ * @param state object advance state (enum ObjectAdvanceState) (unchanged
+ *	on LeafsOnly)
+ * @return a pointer to the render object which we advanced to,
+ *	or 0 if the last possible object has been reached.
+ */
+static RenderObject *advanceObject(RenderObject *r,
+		ObjectTraversalState &trav, bool toBegin,
+                RenderObject *base, int &state)
+{
+
+  ObjectTraversalState origtrav = trav;
+  RenderObject *a = traverseRenderObjects(r, trav, toBegin, base, state);
+
+  bool ignoreOutsideDesc = toBegin && origtrav == OutsideAscending;
+
+  // render object and traversal state at which look ahead has been started
+  RenderObject *la = 0;
+  ObjectTraversalState latrav = trav;
+  ObjectTraversalState lasttrav = origtrav;
+
+  while (a) {
+#if DEBUG_CARETMODE > 5
+kdDebug(6200) << "a " << a << " trav " << trav << endl;
+#endif
+    if (a->element()) {
+#if DEBUG_CARETMODE > 4
+kdDebug(6200) << "a " << a << " trav " << trav << " origtrav " << origtrav << " ignoreOD " << ignoreOutsideDesc << endl;
+#endif
+      if (toBegin) {
+
+        switch (origtrav) {
+	  case OutsideDescending:
+            if (trav == InsideAscending) return a;
+	    if (trav == OutsideDescending) return a;
+	    break;
+          case InsideDescending:
+	    if (trav == OutsideDescending) return a;
+	    // fall through
+          case InsideAscending:
+            if (trav == OutsideAscending) return a;
+	    break;
+	  case OutsideAscending:
+	    if (trav == OutsideAscending) return a;
+            if (trav == InsideAscending && lasttrav == InsideDescending) return a;
+	    if (trav == OutsideDescending && !ignoreOutsideDesc) return a;
+	    // ignore this outside descending position, as it effectively
+	    // demarkates the same position, but remember it in case we fall off
+	    // the document.
+	    la = a; latrav = trav;
+	    ignoreOutsideDesc = false;
+	    break;
+        }/*end switch*/
+
+      } else {
+
+        switch (origtrav) {
+	  case OutsideDescending:
+            if (trav == InsideAscending) return a;
+	    if (trav == OutsideDescending) return a;
+	    break;
+          case InsideDescending:
+//	    if (trav == OutsideDescending) return a;
+	    // fall through
+          case InsideAscending:
+//            if (trav == OutsideAscending) return a;
+//	    break;
+	  case OutsideAscending:
+	    // ### what if origtrav == OA, and immediately afterwards trav
+	    // becomes OD? In this case the effective position hasn't changed ->
+	    // the caret gets stuck. Otherwise, it apparently cannot happen in
+	    // real usage patterns.
+	    if (trav == OutsideDescending) return a;
+	    if (trav == OutsideAscending) {
+	      if (la) return la;
+              // starting lookahead here. Remember old object in case we fall off
+	      // the document.
+	      la = a; latrav = trav;
+	    }
+	    break;
+	}/*end switch*/
+
+      }/*end if*/
+    }/*end if*/
+
+    lasttrav = trav;
+    a = traverseRenderObjects(a, trav, toBegin, base, state);
+  }/*wend*/
+
+  if (la) trav = latrav, a = la;
+  return a;
+
+}
+
+/** Check whether the current render object is unsuitable in caret mode handling.
+ *
+ * Some render objects cannot be handled correctly in caret mode. These objects
+ * are therefore considered to be unsuitable. The null object is suitable, as
+ * it denotes reaching the end.
+ * @param r current render object
+ * @param trav current traversal state
+ */
+static inline bool isUnsuitable(RenderObject *r, ObjectTraversalState trav)
+{
+  if (!r) return false;
+  return r->isTableCol() || r->isTableSection() || r->isTableRow()
+  	|| (r->isText() && static_cast<RenderText *>(r)->inlineTextBoxCount() == 0);
+      ;
+  Q_UNUSED(trav);
+}
+
+/** Advances to the next render object, taking into account the current
+ * traversal state, but skipping render objects which are not suitable for
+ * having placed the caret into them.
+ * @param r render object
+ * @param trav object traversal state (unchanged on LeafsOnly)
+ * @param toBegin @p true, advance towards beginning, @p false, advance toward end
+ * @param base base render object which this method must not advance beyond
+ *	(0 means document)
+ * @param state object advance state (enum ObjectAdvanceState) (unchanged
+ *	on LeafsOnly)
+ * @return a pointer to the advanced render object or 0 if the last possible
+ *	object has been reached.
+ */
+static inline RenderObject *advanceSuitableObject(RenderObject *r,
+		ObjectTraversalState &trav, bool toBegin,
+		RenderObject *base, int &state)
+{
+  do {
+    r = advanceObject(r, trav, toBegin, base, state);
+#if DEBUG_CARETMODE > 2
+    kdDebug(6200) << "after advanceSWP: r " << r << " trav " << trav << " toBegin " << toBegin << endl;
+#endif
+  } while (isUnsuitable(r, trav));
+  return r;
+}
+
+/**
+  * Returns the next leaf node.
+  *
+  * Using this function delivers leaf nodes as if the whole DOM tree
+  * were a linear chain of its leaf nodes.
+  * @param r dom node
+  * @param baseElem base element not to search beyond
+  * @return next leaf node or 0 if there are no more.
+  */
+static NodeImpl *nextLeafNode(NodeImpl *r, NodeImpl *baseElem)
+{
+  NodeImpl *n = r->firstChild();
+  if (n) {
+    while (n) { r = n; n = n->firstChild(); }
+    return const_cast<NodeImpl *>(r);
+  }/*end if*/
+  n = r->nextSibling();
+  if (n) {
+    r = n;
+    while (n) { r = n; n = n->firstChild(); }
+    return const_cast<NodeImpl *>(r);
+  }/*end if*/
+
+  n = r->parentNode();
+  if (n == baseElem) n = 0;
+  while (n) {
+    r = n;
+    n = r->nextSibling();
+    if (n) {
+      r = n;
+      n = r->firstChild();
+      while (n) { r = n; n = n->firstChild(); }
+      return const_cast<NodeImpl *>(r);
+    }/*end if*/
+    n = r->parentNode();
+    if (n == baseElem) n = 0;
+  }/*wend*/
+  return 0;
+}
+
+#if 0		// currently not used
+/** (Not part of the official DOM)
+  * Returns the previous leaf node.
+  *
+  * Using this function delivers leaf nodes as if the whole DOM tree
+  * were a linear chain of its leaf nodes.
+  * @param r dom node
+  * @param baseElem base element not to search beyond
+  * @return previous leaf node or 0 if there are no more.
+  */
+static NodeImpl *prevLeafNode(NodeImpl *r, NodeImpl *baseElem)
+{
+  NodeImpl *n = r->firstChild();
+  if (n) {
+    while (n) { r = n; n = n->firstChild(); }
+    return const_cast<NodeImpl *>(r);
+  }/*end if*/
+  n = r->previousSibling();
+  if (n) {
+    r = n;
+    while (n) { r = n; n = n->firstChild(); }
+    return const_cast<NodeImpl *>(r);
+  }/*end if*/
+
+  n = r->parentNode();
+  if (n == baseElem) n = 0;
+  while (n) {
+    r = n;
+    n = r->previousSibling();
+    if (n) {
+      r = n;
+      n = r->lastChild();
+      while (n) { r = n; n = n->lastChild(); }
+      return const_cast<NodeImpl *>(r);
+    }/*end if*/
+    n = r->parentNode();
+    if (n == baseElem) n = 0;
+  }/*wend*/
+  return 0;
+}
+#endif
+
+/** Maps a DOM Range position to the corresponding caret position.
+ *
+ * The offset boundary is not checked for validity.
+ * @param node DOM node
+ * @param offset zero-based offset within node
+ * @param r returns render object (may be 0 if DOM node has no render object)
+ * @param r_ofs returns the appropriate offset for the found render object r
+ * @param outside returns true when offset is applied to the outside of
+ *	\c r, or false for the inside.
+ * @param outsideEnd return true when the caret position is at the outside end.
+ */
+void /*KDE_NO_EXPORT*/ mapDOMPosToRenderPos(NodeImpl *node, long offset,
+		RenderObject *&r, long &r_ofs, bool &outside, bool &outsideEnd)
+{
+  if (node->nodeType() == Node::TEXT_NODE) {
+    outside = false;
+    outsideEnd = false;
+    r = node->renderer();
+    r_ofs = offset;
+  } else if (node->nodeType() == Node::ELEMENT_NODE || node->nodeType() == Node::DOCUMENT_NODE) {
+
+    // Though offset points between two children, attach it to the visually
+    // most suitable one (and only there, because the mapping must stay bijective)
+    if (node->firstChild()) {
+      outside = true;
+      NodeImpl *child = offset <= 0 ? node->firstChild()
+      				// childNode is expensive
+      				: node->childNode((unsigned long)offset);
+      // index was child count or out of bounds
+      bool atEnd = !child;
+#if DEBUG_CARETMODE > 5
+      kdDebug(6200) << "mapDTR: child " << child << "@" << (child ? child->nodeName().string() : QString::null) << " atEnd " << atEnd << endl;
+#endif
+      if (atEnd) child = node->lastChild();
+
+      r = child->renderer();
+      r_ofs = 0;
+      outsideEnd = atEnd;
+
+      // Outside text nodes most likely stem from a continuation. Seek
+      // the enclosing continued render object and use this one instead.
+      if (r && child->nodeType() == Node::TEXT_NODE) {
+        r = r->parent();
+        RenderObject *o = node->renderer();
+	while (o->continuation() && o->continuation() != r)
+	  o = o->continuation();
+	if (!r || o->continuation() != r) {
+	  r = child->renderer();
+	}
+      }/*end if*/
+
+      // BRs cause troubles. Returns the previous render object instead,
+      // giving it the attributes outside, outside end.
+      if (r && r->isBR()) {
+        r = r->objectAbove();
+        outsideEnd = true;
+      }/*end if*/
+
+    } else {
+      // Element has no children, treat offset to be inside the node.
+      outside = false;
+      outsideEnd = false;
+      r = node->renderer();
+      r_ofs = 0;	// only offset 0 possible
+    }
+
+  } else {
+    r = 0;
+    kdWarning() << k_funcinfo << "Mapping from nodes of type " << node->nodeType()
+        << " not supported!" << endl;
+  }
+}
+
+/** Maps a caret position to the corresponding DOM Range position.
+ *
+ * @param r render object
+ * @param r_ofs offset within render object
+ * @param outside true when offset is interpreted to be on the outside of
+ *	\c r, or false if on the inside.
+ * @param outsideEnd true when the caret position is at the outside end.
+ * @param node returns DOM node
+ * @param offset returns zero-based offset within node
+ */
+void /*KDE_NO_EXPORT*/ mapRenderPosToDOMPos(RenderObject *r, long r_ofs,
+		bool outside, bool outsideEnd, NodeImpl *&node, long &offset)
+{
+  node = r->element();
+  Q_ASSERT(node);
+#if DEBUG_CARETMODE > 5
+      kdDebug(6200) << "mapRTD: r " << r << "@" << (r ? r->renderName() : QString::null) << (r && r->element() ? QString(".node ") + QString::number((unsigned)r->element(),16) + "@" + r->element()->nodeName().string() : QString::null) << " outside " << outside << " outsideEnd " << outsideEnd << endl;
+#endif
+  if (node->nodeType() == Node::ELEMENT_NODE || node->nodeType() == Node::TEXT_NODE) {
+
+    if (outside) {
+      NodeImpl *parent = node->parent();
+
+      // If this is part of a continuation, use the actual node as the parent,
+      // and the first render child as the node.
+      if (r != node->renderer()) {
+        RenderObject *o = node->renderer();
+	while (o->continuation() && o->continuation() != r)
+	  o = o->continuation();
+	if (o->continuation() == r) {
+	  parent = node;
+	  // ### What if the first render child does not map to a child of
+	  // the continued node?
+	  node = r->firstChild() ? r->firstChild()->element() : node;
+	}
+      }/*end if*/
+
+      if (!parent) goto inside;
+
+      offset = (long)node->nodeIndex() + outsideEnd;
+      node = parent;
+#if DEBUG_CARETMODE > 5
+   kdDebug(6200) << node << "@" << (node ? node->nodeName().string() : QString::null) << " offset " << offset << endl;
+#endif
+    } else {	// !outside
+inside:
+      offset = r_ofs;
+    }
+
+  } else {
+    offset = 0;
+    kdWarning() << k_funcinfo << "Mapping to nodes of type " << node->nodeType()
+        << " not supported!" << endl;
+  }
+}
+
+/** Make sure the given node is a leaf node. */
+static inline void ensureLeafNode(NodeImpl *&node, NodeImpl *base)
+{
+  if (node && node->hasChildNodes()) node = nextLeafNode(node, base);
+}
+
+/** Converts a caret position to its respective object traversal state.
+ * @param outside whether the caret is outside the object
+ * @param atEnd whether the caret position is at the end
+ * @param toBegin \c true when advancing towards the beginning
+ * @param trav returns the corresponding traversal state
+ */
+static inline void mapRenderPosToTraversalState(bool outside, bool atEnd,
+		bool toBegin, ObjectTraversalState &trav)
+{
+  if (!outside) atEnd = !toBegin;
+  if (!atEnd ^ toBegin)
+    trav = outside ? OutsideDescending : InsideDescending;
+  else
+    trav = outside ? OutsideAscending : InsideAscending;
+}
+
+/** Converts a traversal state to its respective caret position
+ * @param trav object traversal state
+ * @param toBegin \c true when advancing towards the beginning
+ * @param outside whether the caret is outside the object
+ * @param atEnd whether the caret position is at the end
+ */
+static inline void mapTraversalStateToRenderPos(ObjectTraversalState trav,
+		bool toBegin, bool &outside, bool &atEnd)
+{
+  outside = false;
+  switch (trav) {
+    case OutsideDescending: outside = true; // fall through
+    case InsideDescending: atEnd = toBegin; break;
+    case OutsideAscending: outside = true; // fall through
+    case InsideAscending: atEnd = !toBegin; break;
+  }
+}
+
+/** Finds the next node that has a renderer.
+ *
+ * Note that if the initial @p node has a renderer, this will be returned,
+ * regardless of the caret advance policy.
+ * Otherwise, for the next nodes, only leaf nodes are considered.
+ * @param node node to start with, will be updated accordingly
+ * @param offset offset of caret within \c node
+ * @param base base render object which this method must not advance beyond
+ *	(0 means document)
+ * @param r_ofs return the caret offset within the returned renderer
+ * @param outside returns whether offset is to be interpreted to the outside
+  *	(true) or the inside (false) of the render object.
+ * @param outsideEnd returns whether the end of the outside position is meant
+ * @return renderer or 0 if no following node has a renderer.
+ */
+static RenderObject* findRenderer(NodeImpl *&node, long offset,
+			RenderObject *base, long &r_ofs,
+                        bool &outside, bool &outsideEnd)
+{
+  if (!node) return 0;
+  RenderObject *r;
+  mapDOMPosToRenderPos(node, offset, r, r_ofs, outside, outsideEnd);
+#if DEBUG_CARETMODE > 2
+   kdDebug(6200) << "findRenderer: node " << node << " " << (node ? node->nodeName().string() : QString::null) << " offset " << offset << " r " << r << "[" << (r ? r->renderName() : QString::null) << "] r_ofs " << r_ofs << " outside " << outside << " outsideEnd " << outsideEnd << endl;
+#endif
+  if (r) return r;
+  NodeImpl *baseElem = base ? base->element() : 0;
+  while (!r) {
+    node = nextLeafNode(node, baseElem);
+    if (!node) break;
+    r = node->renderer();
+    if (r) r_ofs = offset;
+  }
+#if DEBUG_CARETMODE > 3
+  kdDebug(6200) << "1r " << r << endl;
+#endif
+  ObjectTraversalState trav;
+  int state;		// not used
+  mapRenderPosToTraversalState(outside, outsideEnd, false, trav);
+  if (r && isUnsuitable(r, trav)) {
+    r = advanceSuitableObject(r, trav, false, base, state);
+    mapTraversalStateToRenderPos(trav, false, outside, outsideEnd);
+    if (r) r_ofs = r->minOffset();
+  }
+#if DEBUG_CARETMODE > 3
+  kdDebug(6200) << "2r " << r << endl;
+#endif
+  return r;
+}
+
+/** returns a suitable base element
+ * @param caretNode current node containing caret.
+ */
+static ElementImpl *determineBaseElement(NodeImpl *caretNode)
+{
+  // ### for now, only body is delivered for html documents,
+  // and 0 for xml documents.
+
+  DocumentImpl *doc = caretNode->getDocument();
+  if (!doc) return 0;	// should not happen, but who knows.
+
+  if (doc->isHTMLDocument())
+    return static_cast<HTMLDocumentImpl *>(doc)->body();
+
+  return 0;
+}
+
+// == class CaretBox implementation
+
+#if DEBUG_CARETMODE > 0
+void CaretBox::dump(QTextStream &ts, const QString &ind) const
+{
+  ts << ind << "b@" << _box;
+
+  if (_box) {
+    ts << "<" << _box->object() << ":" << _box->object()->renderName() << ">";
+  }/*end if*/
+
+  ts << " " << _x << "+" << _y << "+" << _w << "*" << _h;
+
+  ts << " cb@" << cb;
+  if (cb) ts << ":" << cb->renderName();
+
+  ts << " " << (_outside ? (outside_end ? "oe" : "o-") : "i-");
+//  ts << endl;
+}
+#endif
+
+// == class CaretBoxLine implementation
+
+#if DEBUG_CARETMODE > 0
+#  define DEBUG_ACIB 1
+#else
+#  define DEBUG_ACIB DEBUG_CARETMODE
+#endif
+void CaretBoxLine::addConvertedInlineBox(InlineBox *box, SeekBoxParams &sbp) /*KDE_NO_EXPORT*/
+{
+  // Generate only one outside caret box between two elements. If
+  // coalesceOutsideBoxes is true, generating left outside boxes is inhibited.
+  bool coalesceOutsideBoxes = false;
+  CaretBoxIterator lastCoalescedBox;
+  for (; box; box = box->nextOnLine()) {
+#if DEBUG_ACIB
+kdDebug(6200) << "box " << box << endl;
+kdDebug(6200) << "box->object " << box->object() << endl;
+kdDebug(6200) << "x " << box->m_x << " y " << box->m_y << " w " << box->m_width << " h " << box->m_height << " baseline " << box->m_baseline << " ifb " << box->isInlineFlowBox() << " itb " << box->isInlineTextBox() << " rlb " << box->isRootInlineBox() << endl;
+#endif
+    // ### Why the hell can object() ever be 0?!
+    if (!box->object()) continue;
+
+    RenderStyle *s = box->object()->style(box->m_firstLine);
+    // parent style for outside caret boxes
+    RenderStyle *ps = box->parent() && box->parent()->object()
+    		? box->parent()->object()->style(box->parent()->m_firstLine)
+		: s;
+
+    if (box->isInlineFlowBox()) {
+#if DEBUG_ACIB
+kdDebug(6200) << "isinlineflowbox " << box << endl;
+#endif
+      InlineFlowBox *flowBox = static_cast<InlineFlowBox *>(box);
+      bool rtl = ps->direction() == RTL;
+      const QFontMetrics &pfm = ps->fontMetrics();
+
+      if (flowBox->includeLeftEdge()) {
+        // If this box is to be coalesced with the outside end box of its
+        // predecessor, then check if it is the searched box. If it is, we
+        // substitute the outside end box.
+        if (coalesceOutsideBoxes) {
+          if (sbp.equalsBox(flowBox, true, false)) {
+            sbp.it = lastCoalescedBox;
+            Q_ASSERT(!sbp.found);
+            sbp.found = true;
+          }
+        } else {
+          addCreatedFlowBoxEdge(flowBox, pfm, true, rtl);
+          sbp.check(preEnd());
+        }
+      }/*end if*/
+
+      if (flowBox->firstChild()) {
+#if DEBUG_ACIB
+kdDebug(6200) << "this " << this << " flowBox " << flowBox << " firstChild " << flowBox->firstChild() << endl;
+kdDebug(6200) << "== recursive invocation" << endl;
+#endif
+        addConvertedInlineBox(flowBox->firstChild(), sbp);
+#if DEBUG_ACIB
+kdDebug(6200) << "== recursive invocation end" << endl;
+#endif
+}
+      else {
+        addCreatedFlowBoxInside(flowBox, s->fontMetrics());
+        sbp.check(preEnd());
+      }
+
+      if (flowBox->includeRightEdge()) {
+        addCreatedFlowBoxEdge(flowBox, pfm, false, rtl);
+        lastCoalescedBox = preEnd();
+        sbp.check(lastCoalescedBox);
+        coalesceOutsideBoxes = true;
+      }
+
+    } else if (box->isInlineTextBox()) {
+#if DEBUG_ACIB
+kdDebug(6200) << "isinlinetextbox " << box << (box->object() ? QString(" contains \"%1\"").arg(QConstString(static_cast<RenderText *>(box->object())->str->s+box->minOffset(), kMin(box->maxOffset() - box->minOffset(), 15L)).string()) : QString::null) << endl;
+#endif
+      caret_boxes.append(new CaretBox(box, false, false));
+      sbp.check(preEnd());
+      // coalescing has been interrupted
+      coalesceOutsideBoxes = false;
+
+    } else {
+#if DEBUG_ACIB
+kdDebug(6200) << "some replaced or what " << box << endl;
+#endif
+      // must be an inline-block, inline-table, or any RenderReplaced
+      bool rtl = ps->direction() == RTL;
+      const QFontMetrics &pfm = ps->fontMetrics();
+
+      if (coalesceOutsideBoxes) {
+        if (sbp.equalsBox(box, true, false)) {
+          sbp.it = lastCoalescedBox;
+          Q_ASSERT(!sbp.found);
+          sbp.found = true;
+        }
+      } else {
+        addCreatedInlineBoxEdge(box, pfm, true, rtl);
+        sbp.check(preEnd());
+      }
+
+      caret_boxes.append(new CaretBox(box, false, false));
+      sbp.check(preEnd());
+
+      addCreatedInlineBoxEdge(box, pfm, false, rtl);
+      lastCoalescedBox = preEnd();
+      sbp.check(lastCoalescedBox);
+      coalesceOutsideBoxes = true;
+    }/*end if*/
+  }/*next box*/
+}
+#undef DEBUG_ACIB
+
+void CaretBoxLine::addCreatedFlowBoxInside(InlineFlowBox *flowBox, const QFontMetrics &fm) /*KDE_NO_EXPORT*/
+{
+
+  CaretBox *caretBox = new CaretBox(flowBox, false, false);
+  caret_boxes.append(caretBox);
+
+  // afaik an inner flow box can only have the width 0, therefore we don't
+  // have to care for rtl or alignment
+  // ### can empty inline elements have a width? css 2 spec isn't verbose about it
+
+  caretBox->_y += flowBox->baseline() - fm.ascent();
+  caretBox->_h = fm.height();
+}
+
+void CaretBoxLine::addCreatedFlowBoxEdge(InlineFlowBox *flowBox, const QFontMetrics &fm, bool left, bool rtl) /*KDE_NO_EXPORT*/
+{
+  CaretBox *caretBox = new CaretBox(flowBox, true, !left);
+  caret_boxes.append(caretBox);
+
+  if (left ^ rtl) caretBox->_x -= flowBox->paddingLeft() + flowBox->borderLeft() + 1;
+  else caretBox->_x += caretBox->_w + flowBox->paddingRight() + flowBox->borderRight();
+
+  caretBox->_y += flowBox->baseline() - fm.ascent();
+  caretBox->_h = fm.height();
+  caretBox->_w = 1;
+}
+
+void CaretBoxLine::addCreatedInlineBoxEdge(InlineBox *box, const QFontMetrics &fm, bool left, bool rtl) /*KDE_NO_EXPORT*/
+{
+  CaretBox *caretBox = new CaretBox(box, true, !left);
+  caret_boxes.append(caretBox);
+
+  if (left ^ rtl) caretBox->_x--;
+  else caretBox->_x += caretBox->_w;
+
+  caretBox->_y += box->baseline() - fm.ascent();
+  caretBox->_h = fm.height();
+  caretBox->_w = 1;
+}
+
+CaretBoxLine *CaretBoxLine::constructCaretBoxLine(CaretBoxLineDeleter *deleter,
+	InlineFlowBox *basicFlowBox, InlineBox *seekBox, bool seekOutside,
+        bool seekOutsideEnd, CaretBoxIterator &iter, RenderObject *seekObject)
+// 	KDE_NO_EXPORT
+{
+  // Iterate all inline boxes within this inline flow box.
+  // Caret boxes will be created for each
+  // - outside begin of an inline flow box (except for the basic inline flow box)
+  // - outside end of an inline flow box (except for the basic inline flow box)
+  // - inside of an empty inline flow box
+  // - outside begin of an inline box resembling a replaced element
+  // - outside end of an inline box resembling a replaced element
+  // - inline text box
+  // - inline replaced box
+
+  CaretBoxLine *result = new CaretBoxLine(basicFlowBox);
+  deleter->append(result);
+
+  SeekBoxParams sbp(seekBox, seekOutside, seekOutsideEnd, seekObject, iter);
+
+  // iterate recursively, I'm too lazy to do it iteratively
+  result->addConvertedInlineBox(basicFlowBox, sbp);
+
+  if (!sbp.found) sbp.it = result->end();
+
+  return result;
+}
+
+CaretBoxLine *CaretBoxLine::constructCaretBoxLine(CaretBoxLineDeleter *deleter,
+	RenderBox *cb, bool outside, bool outsideEnd, CaretBoxIterator &iter) /*KDE_NO_EXPORT*/
+{
+  int _x = cb->xPos();
+  int _y = cb->yPos();
+  int height;
+  int width = 1;		// no override is indicated in boxes
+
+  if (outside) {
+
+    RenderStyle *s = cb->element() && cb->element()->parent()
+			&& cb->element()->parent()->renderer()
+			? cb->element()->parent()->renderer()->style()
+			: cb->style();
+    bool rtl = s->direction() == RTL;
+
+    const QFontMetrics &fm = s->fontMetrics();
+    height = fm.height();
+
+    if (!outsideEnd) {
+        _x--;
+    } else {
+        _x += cb->width();
+    }
+
+    int hl = fm.leading() / 2;
+    int baseline = cb->baselinePosition(false);
+    if (!cb->isReplaced() || cb->style()->display() == BLOCK) {
+        if (!outsideEnd ^ rtl)
+            _y -= fm.leading() / 2;
+        else
+            _y += kMax(cb->height() - fm.ascent() - hl, 0);
+    } else {
+        _y += baseline - fm.ascent() - hl;
+    }
+
+  } else {		// !outside
+
+    RenderStyle *s = cb->style();
+    const QFontMetrics &fm = s->fontMetrics();
+    height = fm.height();
+
+    _x += cb->borderLeft() + cb->paddingLeft();
+    _y += cb->borderTop() + cb->paddingTop();
+
+    // ### regard direction
+    switch (s->textAlign()) {
+      case LEFT:
+      case KHTML_LEFT:
+      case TAAUTO:	// ### find out what this does
+      case JUSTIFY:
+        break;
+      case CENTER:
+      case KHTML_CENTER:
+        _x += cb->contentWidth() / 2;
+        break;
+      case KHTML_RIGHT:
+      case RIGHT:
+        _x += cb->contentWidth();
+        break;
+    }/*end switch*/
+  }/*end if*/
+
+  CaretBoxLine *result = new CaretBoxLine;
+  deleter->append(result);
+  result->caret_boxes.append(new CaretBox(_x, _y, width, height, cb,
+  			outside, outsideEnd));
+  iter = result->begin();
+  return result;
+}
+
+#if DEBUG_CARETMODE > 0
+void CaretBoxLine::dump(QTextStream &ts, const QString &ind) const
+{
+  ts << ind << "cbl: baseFlowBox@" << basefb << endl;
+  QString ind2 = ind + "  ";
+  for (size_t i = 0; i < caret_boxes.size(); i++) {
+    if (i > 0) ts << endl;
+    caret_boxes[i]->dump(ts, ind2);
+  }
+}
+#endif
+
+// == caret mode related helper functions
+
+/** seeks the root line box that is the parent of the given inline box.
+ * @param b given inline box
+ * @param base base render object which not to step over. If \c base's
+ *	inline flow box is hit before the root line box, the flow box
+ *	is returned instead.
+ * @return the root line box or the base flow box.
+ */
+inline InlineFlowBox *seekBaseFlowBox(InlineBox *b, RenderObject *base = 0)
+{
+  // Seek root line box or base inline flow box, if \c base is interfering.
+  while (b->parent() && b->object() != base) {
+    b = b->parent();
+  }/*wend*/
+  Q_ASSERT(b->isInlineFlowBox());
+  return static_cast<InlineFlowBox *>(b);
+}
+
+/** determines whether the given element is a block level replaced element.
+ */
+inline bool isBlockRenderReplaced(RenderObject *r)
+{
+  return r->isRenderReplaced() && r->style()->display() == BLOCK;
+}
+
+/** determines the caret line box that contains the given position.
+ *
+ * If the node does not map to a render object, the function will snap to
+ * the next suitable render object following it.
+ *
+ * @param node node to begin with
+ * @param offset zero-based offset within node.
+ * @param cblDeleter deleter for caret box lines
+ * @param base base render object which the caret must not be placed beyond.
+ * @param r_ofs adjusted offset within render object
+ * @param caretBoxIt returns an iterator to the caret box that contains the
+ *	given position.
+ * @return the determined caret box lineor 0 if either the node is 0 or
+ *	there is no inline flow box containing this node. The containing block
+ *	will still be set. If it is 0 too, @p node was invalid.
+ */
+static CaretBoxLine* findCaretBoxLine(DOM::NodeImpl *node, long offset,
+		CaretBoxLineDeleter *cblDeleter, RenderObject *base,
+                long &r_ofs, CaretBoxIterator &caretBoxIt)
+{
+  bool outside, outsideEnd;
+  RenderObject *r = findRenderer(node, offset, base, r_ofs, outside, outsideEnd);
+  if (!r) { return 0; }
+#if DEBUG_CARETMODE > 0
+  kdDebug(6200) << "=================== findCaretBoxLine" << endl;
+  kdDebug(6200) << "node " << node << " offset: " << offset << " r " << r->renderName() << "[" << r << "].node " << r->element()->nodeName().string() << "[" << r->element() << "]" << " r_ofs " << r_ofs << " outside " << outside << " outsideEnd " << outsideEnd << endl;
+#endif
+
+  // There are two strategies to find the correct line box. (The third is failsafe)
+  // (A) First, if node's renderer is a RenderText, we only traverse its text
+  // runs and return the root line box (saves much time for long blocks).
+  // This should be the case 99% of the time.
+  // (B) Second, we derive the inline flow box directly when the renderer is
+  // a RenderBlock, RenderInline, or blocked RenderReplaced.
+  // (C) Otherwise, we iterate linearly through all line boxes in order to find
+  // the renderer.
+
+  // (A)
+  if (r->isText()) do {
+    RenderText *t = static_cast<RenderText *>(r);
+    int dummy;
+    InlineBox *b = t->findInlineTextBox(offset, dummy, true);
+    // Actually b should never be 0, but some render texts don't have text
+    // boxes, so we insert the last run as an error correction.
+    // If there is no last run, we resort to (B)
+    if (!b) {
+      if (t->m_lines.count() > 0)
+        b = t->m_lines[t->m_lines.count() - 1];
+      else
+        break;
+    }/*end if*/
+    Q_ASSERT(b);
+    outside = false;	// text boxes cannot have outside positions
+    InlineFlowBox *baseFlowBox = seekBaseFlowBox(b, base);
+#if DEBUG_CARETMODE > 2
+  kdDebug(6200) << "text-box b: " << b << " baseFlowBox: " << baseFlowBox << (b && b->object() ? QString(" contains \"%1\"").arg(QConstString(static_cast<RenderText *>(b->object())->str->s+b->minOffset(), kMin(b->maxOffset() - b->minOffset(), 15L)).string()) : QString::null) << endl;
+#endif
+#if 0
+    if (t->containingBlock()->isListItem()) dumpLineBoxes(static_cast<RenderFlow *>(t->containingBlock()));
+#endif
+#if DEBUG_CARETMODE > 0
+  kdDebug(6200) << "=================== end findCaretBoxLine (renderText)" << endl;
+#endif
+    return CaretBoxLine::constructCaretBoxLine(cblDeleter, baseFlowBox,
+        b, outside, outsideEnd, caretBoxIt);
+  } while(false);/*end if*/
+
+  // (B)
+  bool isrepl = isBlockRenderReplaced(r);
+  if (r->isRenderBlock() || r->isRenderInline() || isrepl) {
+    RenderFlow *flow = static_cast<RenderFlow *>(r);
+    InlineFlowBox *firstLineBox = isrepl ? 0 : flow->firstLineBox();
+
+    // On render blocks, if we are outside, or have a totally empty render
+    // block, we simply construct a special caret box line.
+    // The latter case happens only when the render block is a leaf object itself.
+    if (isrepl || r->isRenderBlock() && (outside || !firstLineBox)
+    		|| r->isRenderInline() && !firstLineBox) {
+  #if DEBUG_CARETMODE > 0
+    kdDebug(6200) << "=================== end findCaretBoxLine (box " << (outside ? (outsideEnd ? "outside end" : "outside begin") : "inside") << ")" << endl;
+  #endif
+      Q_ASSERT(r->isBox());
+      return CaretBoxLine::constructCaretBoxLine(cblDeleter,
+      		static_cast<RenderBox *>(r), outside, outsideEnd, caretBoxIt);
+    }/*end if*/
+
+  kdDebug(6200) << "firstlinebox " << firstLineBox << endl;
+    InlineFlowBox *baseFlowBox = seekBaseFlowBox(firstLineBox, base);
+    return CaretBoxLine::constructCaretBoxLine(cblDeleter, baseFlowBox,
+        firstLineBox, outside, outsideEnd, caretBoxIt);
+  }/*end if*/
+
+  RenderBlock *cb = r->containingBlock();
+  //if ( !cb ) return 0L;
+  Q_ASSERT(cb);
+
+  // ### which element doesn't have a block as its containing block?
+  // Is it still possible after the RenderBlock/RenderInline merge?
+  if (!cb->isRenderBlock()) {
+    kdWarning() << "containing block is no render block!!! crash imminent" << endl;
+  }/*end if*/
+
+  InlineFlowBox *flowBox = cb->firstLineBox();
+  // (C)
+  // This case strikes when the element is replaced, but neither a
+  // RenderBlock nor a RenderInline
+  if (!flowBox) {	// ### utter emergency (why is this possible at all?)
+//    flowBox = generateDummyFlowBox(arena, cb, r);
+//    if (ibox) *ibox = flowBox->firstChild();
+//    outside = outside_end = true;
+
+//    kdWarning() << "containing block contains no inline flow boxes!!! crash imminent" << endl;
+#if DEBUG_CARETMODE > 0
+   kdDebug(6200) << "=================== end findCaretBoxLine (2)" << endl;
+#endif
+    return CaretBoxLine::constructCaretBoxLine(cblDeleter, cb,
+			outside, outsideEnd, caretBoxIt);
+  }/*end if*/
+
+  // We iterate the inline flow boxes of the containing block until
+  // we find the given node. This has one major flaw: it is linear, and therefore
+  // painfully slow for really large blocks.
+  for (; flowBox; flowBox = static_cast<InlineFlowBox *>(flowBox->nextLineBox())) {
+#if DEBUG_CARETMODE > 0
+    kdDebug(6200) << "[scan line]" << endl;
+#endif
+
+    // construct a caret line box and stop when the element is contained within
+    InlineFlowBox *baseFlowBox = seekBaseFlowBox(flowBox, base);
+    CaretBoxLine *cbl = CaretBoxLine::constructCaretBoxLine(cblDeleter,
+        baseFlowBox, 0, outside, outsideEnd, caretBoxIt, r);
+#if DEBUG_CARETMODE > 5
+    kdDebug(6200) << cbl->information() << endl;
+#endif
+    if (caretBoxIt != cbl->end()) {
+#if DEBUG_CARETMODE > 0
+   kdDebug(6200) << "=================== end findCaretBoxLine (3)" << endl;
+#endif
+      return cbl;
+    }
+  }/*next flowBox*/
+
+  // no inline flow box found, approximate to nearest following node.
+  // Danger: this is O(n^2). It's only called to recover from
+  // errors, that means, theoretically, never. (Practically, far too often :-( )
+  Q_ASSERT(!flowBox);
+  CaretBoxLine *cbl = findCaretBoxLine(nextLeafNode(node, base ? base->element() : 0), 0, cblDeleter, base, r_ofs, caretBoxIt);
+#if DEBUG_CARETMODE > 0
+  kdDebug(6200) << "=================== end findCaretBoxLine" << endl;
+#endif
+  return cbl;
+}
+
+/** finds the innermost table object @p r is contained within, but no
+ * farther than @p cb.
+ * @param r leaf element to begin with
+ * @param cb bottom element where to stop search at least.
+ * @return the table object or 0 if none found.
+ */
+static inline RenderTable *findTableUpTo(RenderObject *r, RenderFlow *cb)
+{
+  while (r && r != cb && !r->isTable()) r = r->parent();
+  return r && r->isTable() ? static_cast<RenderTable *>(r) : 0;
+}
+
+/** checks whether @p r is a descendant of @p cb, or r == cb
+ */
+static inline bool isDescendant(RenderObject *r, RenderObject *cb)
+{
+  while (r && r != cb) r = r->parent();
+  return r;
+}
+
+/** checks whether the given block contains at least one editable element.
+ *
+ * Warning: This function has linear complexity, and therefore is expensive.
+ * Use it sparingly, and cache the result.
+ * @param part part
+ * @param cb block to be searched
+ * @param table returns the nested table if there is one directly at the beginning
+ *	or at the end.
+ * @param fromEnd begin search from end (default: begin from beginning)
+ */
+static bool containsEditableElement(KHTMLPart *part, RenderBlock *cb,
+	RenderTable *&table, bool fromEnd = false)
+{
+  RenderObject *r = cb;
+  if (fromEnd)
+    while (r->lastChild()) r = r->lastChild();
+  else
+    while (r->firstChild()) r = r->firstChild();
+
+  RenderTable *tempTable = 0;
+  table = 0;
+  bool withinCb;
+//  int state;		// not used
+  ObjectTraversalState trav = InsideDescending;
+  do {
+    bool modWithinCb = withinCb = isDescendant(r, cb);
+
+    // treat cb extra, it would not be considered otherwise
+    if (!modWithinCb) {
+      modWithinCb = true;
+      r = cb;
+    } else
+      tempTable = findTableUpTo(r, cb);
+
+#if DEBUG_CARETMODE > 1
+    kdDebug(6201) << "cee: r " << (r ? r->renderName() : QString::null) << "@" << r << " cb " << cb << " withinCb " << withinCb << " modWithinCb " << modWithinCb << " tempTable " << tempTable << endl;
+#endif
+    if (r && modWithinCb && r->element() && !isUnsuitable(r, trav)
+    	&& (part->isCaretMode() || part->isEditable()
+		|| r->style()->userInput() == UI_ENABLED)) {
+      table = tempTable;
+#if DEBUG_CARETMODE > 1
+    kdDebug(6201) << "cee: editable" << endl;
+#endif
+      return true;
+    }/*end if*/
+
+//    RenderObject *oldr = r;
+//    while (r && r == oldr)
+//      r = advanceSuitableObject(r, trav, fromEnd, cb->parent(), state);
+    r = fromEnd ? r->objectAbove() : r->objectBelow();
+  } while (r && withinCb);
+  return false;
+}
+
+/** checks whether the given block contains at least one editable child
+ * element, beginning with but excluding @p start.
+ *
+ * Warning: This function has linear complexity, and therefore is expensive.
+ * Use it sparingly, and cache the result.
+ * @param part part
+ * @param cb block to be searched
+ * @param table returns the nested table if there is one directly before/after
+ *	the start object.
+ * @param fromEnd begin search from end (default: begin from beginning)
+ * @param start object after which to begin search.
+ */
+static bool containsEditableChildElement(KHTMLPart *part, RenderBlock *cb,
+	RenderTable *&table, bool fromEnd, RenderObject *start)
+{
+  int state = 0;
+  ObjectTraversalState trav = OutsideAscending;
+// kdDebug(6201) << "start: " << start << endl;
+  RenderObject *r = start;
+  do {
+    r = traverseRenderObjects(r, trav, fromEnd, cb->parent(), state);
+  } while(r && !(state & AdvancedToSibling));
+// kdDebug(6201) << "r: " << r << endl;
+  //advanceObject(start, trav, fromEnd, cb->parent(), state);
+//     RenderObject *oldr = r;
+//     while (r && r == oldr)
+  if (!r) return false;
+
+  if (fromEnd)
+    while (r->firstChild()) r = r->firstChild();
+  else
+    while (r->lastChild()) r = r->lastChild();
+// kdDebug(6201) << "child r: " << r << endl;
+  if (!r) return false;
+
+  RenderTable *tempTable = 0;
+  table = 0;
+  bool withinCb = false;
+  do {
+
+    bool modWithinCb = withinCb = isDescendant(r, cb);
+
+    // treat cb extra, it would not be considered otherwise
+    if (!modWithinCb) {
+      modWithinCb = true;
+      r = cb;
+    } else
+      tempTable = findTableUpTo(r, cb);
+
+#if DEBUG_CARETMODE > 1
+    kdDebug(6201) << "cece: r " << (r ? r->renderName() : QString::null) << "@" << r << " cb " << cb << " withinCb " << withinCb << " modWithinCb " << modWithinCb << " tempTable " << tempTable << endl;
+#endif
+    if (r && withinCb && r->element() && !isUnsuitable(r, trav)
+    	&& (part->isCaretMode() || part->isEditable()
+		|| r->style()->userInput() == UI_ENABLED)) {
+      table = tempTable;
+#if DEBUG_CARETMODE > 1
+    kdDebug(6201) << "cece: editable" << endl;
+#endif
+      return true;
+    }/*end if*/
+
+    r = fromEnd ? r->objectAbove() : r->objectBelow();
+  } while (withinCb);
+  return false;
+}
+
+// == class LinearDocument implementation
+
+LinearDocument::LinearDocument(KHTMLPart *part, NodeImpl *node, long offset,
+  		CaretAdvancePolicy advancePolicy, ElementImpl *baseElem)
+	: node(node), offset(offset), m_part(part),
+	advPol(advancePolicy), base(0)
+{
+  if (node == 0) return;
+
+  if (baseElem) {
+    RenderObject *b = baseElem->renderer();
+    if (b && (b->isRenderBlock() || b->isRenderInline()))
+      base = b;
+  }
+
+  initPreBeginIterator();
+  initEndIterator();
+}
+
+LinearDocument::~LinearDocument()
+{
+}
+
+int LinearDocument::count() const
+{
+  // FIXME: not implemented
+  return 1;
+}
+
+LinearDocument::Iterator LinearDocument::current()
+{
+  return LineIterator(this, node, offset);
+}
+
+LinearDocument::Iterator LinearDocument::begin()
+{
+  NodeImpl *n = base ? base->element() : 0;
+  if (!base) n = node ? node->getDocument() : 0;
+  if (!n) return end();
+
+  n = n->firstChild();
+  if (advPol == LeafsOnly)
+    while (n->firstChild()) n = n->firstChild();
+
+  if (!n) return end();		// must be empty document or empty base element
+  return LineIterator(this, n, n->minOffset());
+}
+
+LinearDocument::Iterator LinearDocument::preEnd()
+{
+  NodeImpl *n = base ? base->element() : 0;
+  if (!base) n = node ? node->getDocument() : 0;
+  if (!n) return preBegin();
+
+  n = n->lastChild();
+  if (advPol == LeafsOnly)
+    while (n->lastChild()) n = n->lastChild();
+
+  if (!n) return preBegin();	// must be empty document or empty base element
+  return LineIterator(this, n, n->maxOffset());
+}
+
+void LinearDocument::initPreBeginIterator()
+{
+  _preBegin = LineIterator(this, 0, 0);
+}
+
+void LinearDocument::initEndIterator()
+{
+  _end = LineIterator(this, 0, 1);
+}
+
+// == class LineIterator implementation
+
+CaretBoxIterator LineIterator::currentBox /*KDE_NO_EXPORT*/;
+long LineIterator::currentOffset /*KDE_NO_EXPORT*/;
+
+LineIterator::LineIterator(LinearDocument *l, DOM::NodeImpl *node, long offset)
+		: lines(l)
+{
+//  kdDebug(6200) << "LineIterator: node " << node << " offset " << offset << endl;
+  if (!node) { cbl = 0; return; }
+  cbl = findCaretBoxLine(node, offset, &lines->cblDeleter,
+  		l->baseObject(), currentOffset, currentBox);
+  // can happen on partially loaded documents
+#if DEBUG_CARETMODE > 0
+  if (!cbl) kdDebug(6200) << "no render object found!" << endl;
+#endif
+  if (!cbl) return;
+#if DEBUG_CARETMODE > 1
+  kdDebug(6200) << "LineIterator: offset " << offset << " outside " << cbl->isOutside() << endl;
+#endif
+#if DEBUG_CARETMODE > 3
+  kdDebug(6200) << cbl->information() << endl;
+#endif
+  if (currentBox == cbl->end()) {
+#if DEBUG_CARETMODE > 0
+    kdDebug(6200) << "LineIterator: findCaretBoxLine failed" << endl;
+#endif
+    cbl = 0;
+  }/*end if*/
+}
+
+void LineIterator::nextBlock()
+{
+  RenderObject *base = lines->baseObject();
+
+  bool cb_outside = cbl->isOutside();
+  bool cb_outside_end = cbl->isOutsideEnd();
+
+  {
+    RenderObject *r = cbl->enclosingObject();
+
+    ObjectTraversalState trav;
+    int state;		// not used
+    mapRenderPosToTraversalState(cb_outside, cb_outside_end, false, trav);
+#if DEBUG_CARETMODE > 1
+    kdDebug(6200) << "nextBlock: before adv r" << r << " " << (r ? r->renderName() : QString::null) << (r && r->isText() ? " contains \"" + QString(((RenderText *)r)->str->s, QMIN(((RenderText *)r)->str->l,15)) + "\"" : QString::null) << " trav " << trav << " cb_outside " << cb_outside << " cb_outside_end " << cb_outside_end << endl;
+#endif
+    r = advanceSuitableObject(r, trav, false, base, state);
+    if (!r) {
+      cbl = 0;
+      return;
+    }/*end if*/
+
+    mapTraversalStateToRenderPos(trav, false, cb_outside, cb_outside_end);
+#if DEBUG_CARETMODE > 1
+    kdDebug(6200) << "nextBlock: after r" << r << " trav " << trav << " cb_outside " << cb_outside << " cb_outside_end " << cb_outside_end << endl;
+#endif
+#if DEBUG_CARETMODE > 0
+    kdDebug(6200) << "++: r " << r << "[" << (r?r->renderName():QString::null) << "]" << endl;
+#endif
+
+    RenderBlock *cb;
+
+    // If we hit a block or replaced object, use this as its enclosing object
+    bool isrepl = isBlockRenderReplaced(r);
+    if (r->isRenderBlock() || isrepl) {
+      RenderBox *cb = static_cast<RenderBox *>(r);
+
+      cbl = CaretBoxLine::constructCaretBoxLine(&lines->cblDeleter, cb,
+			cb_outside, cb_outside_end, currentBox);
+
+#if DEBUG_CARETMODE > 0
+      kdDebug(6200) << "r->isFlow is cb. continuation @" << cb->continuation() << endl;
+#endif
+      return;
+    } else {
+      cb = r->containingBlock();
+      Q_ASSERT(cb->isRenderBlock());
+    }/*end if*/
+    InlineFlowBox *flowBox = cb->firstLineBox();
+#if DEBUG_CARETMODE > 0
+    kdDebug(6200) << "++: flowBox " << flowBox << " cb " << cb << "[" << (cb?cb->renderName()+QString(".node ")+QString::number((unsigned)cb->element(),16)+(cb->element()?"@"+cb->element()->nodeName().string():QString::null):QString::null) << "]" << endl;
+#endif
+    Q_ASSERT(flowBox);
+    if (!flowBox) {	// ### utter emergency (why is this possible at all?)
+      cb_outside = cb_outside_end = true;
+      cbl = CaretBoxLine::constructCaretBoxLine(&lines->cblDeleter, cb,
+			cb_outside, cb_outside_end, currentBox);
+      return;
+    }
+
+    bool seekOutside = false, seekOutsideEnd = false; // silence gcc uninit warning
+    CaretBoxIterator it;
+    cbl = CaretBoxLine::constructCaretBoxLine(&lines->cblDeleter,
+  	flowBox, flowBox->firstChild(), seekOutside, seekOutsideEnd, it);
+  }
+}
+
+void LineIterator::prevBlock()
+{
+  RenderObject *base = lines->baseObject();
+
+  bool cb_outside = cbl->isOutside();
+  bool cb_outside_end = cbl->isOutsideEnd();
+
+  {
+    RenderObject *r = cbl->enclosingObject();
+    if (r->isAnonymous() && !cb_outside)
+      cb_outside = true, cb_outside_end = false;
+
+    ObjectTraversalState trav;
+    int state;		// not used
+    mapRenderPosToTraversalState(cb_outside, cb_outside_end, true, trav);
+#if DEBUG_CARETMODE > 1
+    kdDebug(6200) << "prevBlock: before adv r" << r << " " << (r ? r->renderName() : QString::null) << (r && r->isText() ? " contains \"" + QString(((RenderText *)r)->str->s, QMIN(((RenderText *)r)->str->l,15)) + "\"" : QString::null) << " trav " << trav << " cb_outside " << cb_outside << " cb_outside_end " << cb_outside_end << endl;
+#endif
+    r = advanceSuitableObject(r, trav, true, base, state);
+    if (!r) {
+      cbl = 0;
+      return;
+    }/*end if*/
+
+    mapTraversalStateToRenderPos(trav, true, cb_outside, cb_outside_end);
+#if DEBUG_CARETMODE > 1
+    kdDebug(6200) << "prevBlock: after r" << r << " trav " << trav << " cb_outside " << cb_outside << " cb_outside_end " << cb_outside_end << endl;
+#endif
+#if DEBUG_CARETMODE > 0
+    kdDebug(6200) << "--: r " << r << "[" << (r?r->renderName():QString::null) << "]" << endl;
+#endif
+
+    RenderBlock *cb;
+
+    // If we hit a block, use this as its enclosing object
+    bool isrepl = isBlockRenderReplaced(r);
+//    kdDebug(6200) << "isrepl " << isrepl << " isblock " << r->isRenderBlock() << endl;
+    if (r->isRenderBlock() || isrepl) {
+      RenderBox *cb = static_cast<RenderBox *>(r);
+
+      cbl = CaretBoxLine::constructCaretBoxLine(&lines->cblDeleter, cb,
+			cb_outside, cb_outside_end, currentBox);
+
+#if DEBUG_CARETMODE > 0
+      kdDebug(6200) << "r->isFlow is cb. continuation @" << cb->continuation() << endl;
+#endif
+      return;
+    } else {
+      cb = r->containingBlock();
+      Q_ASSERT(cb->isRenderBlock());
+    }/*end if*/
+    InlineFlowBox *flowBox = cb->lastLineBox();
+#if DEBUG_CARETMODE > 0
+    kdDebug(6200) << "--: flowBox " << flowBox << " cb " << cb << "[" << (cb?cb->renderName()+QString(".node ")+QString::number((unsigned)cb->element(),16)+(cb->element()?"@"+cb->element()->nodeName().string():QString::null):QString::null) << "]" << endl;
+#endif
+    Q_ASSERT(flowBox);
+    if (!flowBox) {	// ### utter emergency (why is this possible at all?)
+      cb_outside = true; cb_outside_end = false;
+      cbl = CaretBoxLine::constructCaretBoxLine(&lines->cblDeleter, cb,
+			cb_outside, cb_outside_end, currentBox);
+      return;
+    }
+
+    bool seekOutside = false, seekOutsideEnd = false; // silence gcc uninit warning
+    CaretBoxIterator it;
+    cbl = CaretBoxLine::constructCaretBoxLine(&lines->cblDeleter,
+  	flowBox, flowBox->firstChild(), seekOutside, seekOutsideEnd, it);
+  }
+}
+
+void LineIterator::advance(bool toBegin)
+{
+  InlineFlowBox *flowBox = cbl->baseFlowBox();
+  if (flowBox) {
+    flowBox = static_cast<InlineFlowBox *>(toBegin ? flowBox->prevLineBox() : flowBox->nextLineBox());
+    if (flowBox) {
+      bool seekOutside = false, seekOutsideEnd = false; // silence gcc uninit warning
+      CaretBoxIterator it;
+      cbl = CaretBoxLine::constructCaretBoxLine(&lines->cblDeleter,
+          flowBox, flowBox->firstChild(), seekOutside, seekOutsideEnd, it);
+    }/*end if*/
+  }/*end if*/
+
+  // if there are no more lines in this block, move towards block to come
+  if (!flowBox) { if (toBegin) prevBlock(); else nextBlock(); }
+
+#if DEBUG_CARETMODE > 3
+  if (cbl) kdDebug(6200) << cbl->information() << endl;
+#endif
+}
+
+// == class EditableCaretBoxIterator implementation
+
+void EditableCaretBoxIterator::advance(bool toBegin)
+{
+#if DEBUG_CARETMODE > 3
+      kdDebug(6200) << "---------------" << k_funcinfo << "toBegin " << toBegin << endl;
+#endif
+  const CaretBoxIterator preBegin = cbl->preBegin();
+  const CaretBoxIterator end = cbl->end();
+
+  CaretBoxIterator lastbox = *this, curbox;
+  bool islastuseable = true;	// silence gcc
+  bool iscuruseable;
+  // Assume adjacency of caret boxes. Will be falsified later if applicable.
+  adjacent = true;
+
+#if DEBUG_CARETMODE > 4
+//       kdDebug(6200) << "ebit::advance: before: " << (**this)->object() << "@" << (**this)->object()->renderName() << ".node " << (**this)->object()->element() << "[" << ((**this)->object()->element() ? (**this)->object()->element()->nodeName().string() : QString::null) << "] inline " << (**this)->isInline() << " outside " << (**this)->isOutside() << " outsideEnd " << (**this)->isOutsideEnd() << endl;
+#endif
+
+  if (toBegin) CaretBoxIterator::operator --(); else CaretBoxIterator::operator ++();
+  bool curAtEnd = *this == preBegin || *this == end;
+  curbox = *this;
+  bool atEnd = true;
+  if (!curAtEnd) {
+    iscuruseable = isEditable(curbox, toBegin);
+    if (toBegin) CaretBoxIterator::operator --(); else CaretBoxIterator::operator ++();
+    atEnd = *this == preBegin || *this == end;
+  }
+  while (!curAtEnd) {
+    bool haslast = lastbox != end && lastbox != preBegin;
+    bool hascoming = !atEnd;
+    bool iscominguseable = true; // silence gcc
+
+    if (!atEnd) iscominguseable = isEditable(*this, toBegin);
+    if (iscuruseable) {
+#if DEBUG_CARETMODE > 3
+      kdDebug(6200) << "ebit::advance: " << (*curbox)->object() << "@" << (*curbox)->object()->renderName() << ".node " << (*curbox)->object()->element() << "[" << ((*curbox)->object()->element() ? (*curbox)->object()->element()->nodeName().string() : QString::null) << "] inline " << (*curbox)->isInline() << " outside " << (*curbox)->isOutside() << " outsideEnd " << (*curbox)->isOutsideEnd() << endl;
+#endif
+
+      CaretBox *box = *curbox;
+      if (box->isOutside()) {
+        // if this caret box represents no inline box, it is an outside box
+	// which has to be considered unconditionally
+        if (!box->isInline()) break;
+
+        if (advpol == VisibleFlows) break;
+
+	// IndicatedFlows and LeafsOnly are treated equally in caret box lines
+
+	InlineBox *ibox = box->inlineBox();
+	// get previous inline box
+	InlineBox *prev = box->isOutsideEnd() ? ibox : ibox->prevOnLine();
+	// get next inline box
+	InlineBox *next = box->isOutsideEnd() ? ibox->nextOnLine() : ibox;
+
+	const bool isprevindicated = !prev || isIndicatedInlineBox(prev);
+	const bool isnextindicated = !next || isIndicatedInlineBox(next);
+	const bool last = haslast && !islastuseable;
+	const bool coming = hascoming && !iscominguseable;
+	const bool left = !prev || prev->isInlineFlowBox() && isprevindicated
+		|| (toBegin && coming || !toBegin && last);
+	const bool right = !next || next->isInlineFlowBox() && isnextindicated
+		|| (!toBegin && coming || toBegin && last);
+        const bool text2indicated = toBegin && next && next->isInlineTextBox()
+                && isprevindicated
+            || !toBegin && prev && prev->isInlineTextBox() && isnextindicated;
+        const bool indicated2text = !toBegin && next && next->isInlineTextBox()
+                && prev && isprevindicated
+            // ### this code is so broken.
+            /*|| toBegin && prev && prev->isInlineTextBox() && isnextindicated*/;
+#if DEBUG_CARETMODE > 5
+      kdDebug(6200) << "prev " << prev << " haslast " << haslast << " islastuseable " << islastuseable << " left " << left << " next " << next << " hascoming " << hascoming << " iscominguseable " << iscominguseable << " right " << right << " text2indicated " << text2indicated << " indicated2text " << indicated2text << endl;
+#endif
+
+	if (left && right && !text2indicated || indicated2text) {
+	  adjacent = false;
+#if DEBUG_CARETMODE > 4
+      kdDebug(6200) << "left && right && !text2indicated || indicated2text" << endl;
+#endif
+	  break;
+	}
+
+      } else {
+        // inside boxes are *always* valid
+#if DEBUG_CARETMODE > 4
+if (box->isInline()) {
+        InlineBox *ibox = box->inlineBox();
+      kdDebug(6200) << "inside " << (!ibox->isInlineFlowBox() || static_cast<InlineFlowBox *>(ibox)->firstChild() ? "non-empty" : "empty") << (isIndicatedInlineBox(ibox) ? " indicated" : "") << " adjacent=" << adjacent << endl;
+    }
+#if 0
+  RenderStyle *s = ibox->object()->style();
+  kdDebug(6200)	<< "bordls " << s->borderLeftStyle()
+  		<< " bordl " << (s->borderLeftStyle() != BNONE)
+  		<< " bordr " << (s->borderRightStyle() != BNONE)
+  		<< " bordt " << (s->borderTopStyle() != BNONE)
+      		<< " bordb " << (s->borderBottomStyle() != BNONE)
+		<< " padl " << s->paddingLeft().value()
+                << " padr " << s->paddingRight().value()
+      		<< " padt " << s->paddingTop().value()
+                << " padb " << s->paddingBottom().value()
+	// ### Can inline elements have top/bottom margins? Couldn't find
+	// it in the CSS 2 spec, but Mozilla ignores them, so we do, too.
+		<< " marl " << s->marginLeft().value()
+                << " marr " << s->marginRight().value()
+      		<< endl;
+#endif
+#endif
+        break;
+      }/*end if*/
+
+    } else {
+
+      if (!(*curbox)->isOutside()) {
+        // cannot be adjacent anymore
+	adjacent = false;
+      }
+
+    }/*end if*/
+    lastbox = curbox;
+    islastuseable = iscuruseable;
+    curbox = *this;
+    iscuruseable = iscominguseable;
+    curAtEnd = atEnd;
+    if (!atEnd) {
+      if (toBegin) CaretBoxIterator::operator --(); else CaretBoxIterator::operator ++();
+      atEnd = *this == preBegin || *this == end;
+    }/*end if*/
+  }/*wend*/
+
+  *static_cast<CaretBoxIterator *>(this) = curbox;
+#if DEBUG_CARETMODE > 4
+//  kdDebug(6200) << "still valid? " << (*this != preBegin && *this != end) << endl;
+#endif
+#if DEBUG_CARETMODE > 3
+      kdDebug(6200) << "---------------" << k_funcinfo << "end " << endl;
+#endif
+}
+
+bool EditableCaretBoxIterator::isEditable(const CaretBoxIterator &boxit, bool fromEnd)
+{
+  Q_ASSERT(boxit != cbl->end() && boxit != cbl->preBegin());
+  CaretBox *b = *boxit;
+  RenderObject *r = b->object();
+#if DEBUG_CARETMODE > 0
+//  if (b->isInlineFlowBox()) kdDebug(6200) << "b is inline flow box" << (outside ? " (outside)" : "") << endl;
+  kdDebug(6200) << "isEditable r" << r << ": " << (r ? r->renderName() : QString::null) << (r && r->isText() ? " contains \"" + QString(((RenderText *)r)->str->s, QMIN(((RenderText *)r)->str->l,15)) + "\"" : QString::null) << endl;
+#endif
+  // Must check caret mode or design mode *after* r->element(), otherwise
+  // lines without a backing DOM node get regarded, leading to a crash.
+  // ### check should actually be in InlineBoxIterator
+  NodeImpl *node = r->element();
+  ObjectTraversalState trav;
+  mapRenderPosToTraversalState(b->isOutside(), b->isOutsideEnd(), fromEnd, trav);
+  if (isUnsuitable(r, trav) || !node) {
+    return false;
+  }
+
+  // generally exclude replaced elements with no children from navigation
+  if (!b->isOutside() && r->isRenderReplaced() && !r->firstChild())
+    return false;
+
+  RenderObject *eff_r = r;
+  bool globallyNavigable = m_part->isCaretMode() || m_part->isEditable();
+
+  // calculate the parent element's editability if this inline box is outside.
+  if (b->isOutside() && !globallyNavigable) {
+    NodeImpl *par = node->parent();
+    // I wonder whether par can be 0. It shouldn't be possible if the
+    // algorithm contained no bugs.
+    Q_ASSERT(par);
+    if (par) node = par;
+    eff_r = node->renderer();
+    Q_ASSERT(eff_r);	// this is a hard requirement
+  }
+
+  bool result = globallyNavigable || eff_r->style()->userInput() == UI_ENABLED;
+#if DEBUG_CARETMODE > 0
+  kdDebug(6200) << result << endl;
+#endif
+  return result;
+}
+
+// == class EditableLineIterator implementation
+
+void EditableLineIterator::advance(bool toBegin)
+{
+  CaretAdvancePolicy advpol = lines->advancePolicy();
+  LineIterator lasteditable, lastindicated;
+  bool haslasteditable = false;
+  bool haslastindicated = false;
+  bool uselasteditable = false;
+
+  LineIterator::advance(toBegin);
+  while (cbl) {
+    if (isEditable(*this)) {
+#if DEBUG_CARETMODE > 3
+      kdDebug(6200) << "advance: " << cbl->enclosingObject() << "@" << cbl->enclosingObject()->renderName() << ".node " << cbl->enclosingObject()->element() << "[" << (cbl->enclosingObject()->element() ? cbl->enclosingObject()->element()->nodeName().string() : QString::null) << "]" << endl;
+#endif
+
+      bool hasindicated = isIndicatedFlow(cbl->enclosingObject());
+      if (hasindicated) {
+        haslastindicated = true;
+        lastindicated = *this;
+      }
+
+      switch (advpol) {
+        case IndicatedFlows:
+          if (hasindicated) goto wend;
+          // fall through
+        case LeafsOnly:
+          if (cbl->isOutside()) break;
+          // fall through
+        case VisibleFlows: goto wend;
+      }/*end switch*/
+
+      // remember rejected editable element
+      lasteditable = *this;
+      haslasteditable = true;
+#if DEBUG_CARETMODE > 4
+      kdDebug(6200) << "remembered lasteditable " << *lasteditable << endl;
+#endif
+    } else {
+
+      // If this element isn't editable, but the last one was, and it was only
+      // rejected because it didn't match the caret advance policy, force it.
+      // Otherwise certain combinations of editable and uneditable elements
+      // could never be reached with some policies.
+      if (haslasteditable) { uselasteditable = true; break; }
+
+    }
+    LineIterator::advance(toBegin);
+  }/*wend*/
+wend:
+
+  if (uselasteditable) *this = haslastindicated ? lastindicated : lasteditable;
+  if (!cbl && haslastindicated) *this = lastindicated;
+}
+
+// == class EditableCharacterIterator implementation
+
+void EditableCharacterIterator::initFirstChar()
+{
+  CaretBox *box = *ebit;
+  InlineBox *b = box->inlineBox();
+  if (_offset == box->maxOffset())
+    peekNext();
+  else if (b && !box->isOutside() && b->isInlineTextBox())
+    _char = static_cast<RenderText *>(b->object())->str->s[_offset].unicode();
+  else
+    _char = -1;
+}
+
+/** returns true when the given caret box is empty, i. e. should not
+ * take place in caret movement.
+ */
+static inline bool isCaretBoxEmpty(CaretBox *box) {
+  if (!box->isInline()) return false;
+  InlineBox *ibox = box->inlineBox();
+  return ibox->isInlineFlowBox()
+  		&& !static_cast<InlineFlowBox *>(ibox)->firstChild()
+      		&& !isIndicatedInlineBox(ibox);
+}
+
+EditableCharacterIterator &EditableCharacterIterator::operator ++()
+{
+  _offset++;
+
+  CaretBox *box = *ebit;
+  InlineBox *b = box->inlineBox();
+  long maxofs = box->maxOffset();
+#if DEBUG_CARETMODE > 0
+  kdDebug(6200) << "box->maxOffset() " << box->maxOffset() << " box->minOffset() " << box->minOffset() << endl;
+#endif
+  if (_offset == maxofs) {
+#if DEBUG_CARETMODE > 2
+kdDebug(6200) << "_offset == maxofs: " << _offset << " == " << maxofs << endl;
+#endif
+    peekNext();
+  } else if (_offset > maxofs) {
+#if DEBUG_CARETMODE > 2
+kdDebug(6200) << "_offset > maxofs: " << _offset << " > " << maxofs /*<< " _peekNext: " << _peekNext*/ << endl;
+#endif
+    if (/*!_peekNext*/true) {
+      ++ebit;
+      if (ebit == (*_it)->end()) {	// end of line reached, go to next line
+        ++_it;
+#if DEBUG_CARETMODE > 3
+kdDebug(6200) << "++_it" << endl;
+#endif
+        if (_it != _it.lines->end()) {
+	  ebit = _it;
+          box = *ebit;
+          b = box->inlineBox();
+#if DEBUG_CARETMODE > 3
+kdDebug(6200) << "box " << box << " b " << b << " isText " << box->isInlineTextBox() << endl;
+#endif
+
+#if DEBUG_CARETMODE > 3
+	  RenderObject *_r = box->object();
+kdDebug(6200) << "_r " << _r << ":" << _r->element()->nodeName().string() << endl;
+#endif
+	  _offset = box->minOffset();
+#if DEBUG_CARETMODE > 3
+kdDebug(6200) << "_offset " << _offset << endl;
+#endif
+	} else {
+          b = 0;
+	  _end = true;
+	}/*end if*/
+        goto readchar;
+      }/*end if*/
+    }/*end if*/
+
+    bool adjacent = ebit.isAdjacent();
+#if 0
+    // Jump over element if this one is not a text node.
+    if (adjacent && !(*ebit)->isInlineTextBox()) {
+      EditableCaretBoxIterator copy = ebit;
+      ++ebit;
+      if (ebit != (*_it)->end() && (*ebit)->isInlineTextBox()
+          /*&& (!(*ebit)->isInlineFlowBox()
+              || static_cast<InlineFlowBox *>(*ebit)->)*/)
+        adjacent = false;
+      else ebit = copy;
+    }/*end if*/
+#endif
+    // Jump over empty elements.
+    if (adjacent && !(*ebit)->isInlineTextBox()) {
+      bool noemptybox = true;
+      while (isCaretBoxEmpty(*ebit)) {
+        noemptybox = false;
+        EditableCaretBoxIterator copy = ebit;
+        ++ebit;
+        if (ebit == (*_it)->end()) { ebit = copy; break; }
+      }
+      if (noemptybox) adjacent = false;
+    }/*end if*/
+//     _r = (*ebit)->object();
+    /*if (!_it.outside) */_offset = (*ebit)->minOffset() + adjacent;
+    //_peekNext = 0;
+    box = *ebit;
+    b = box->inlineBox();
+    goto readchar;
+  } else {
+readchar:
+    // get character
+    if (b && !box->isOutside() && b->isInlineTextBox() && _offset < b->maxOffset())
+      _char = static_cast<RenderText *>(b->object())->str->s[_offset].unicode();
+    else
+      _char = -1;
+  }/*end if*/
+#if DEBUG_CARETMODE > 2
+kdDebug(6200) << "_offset: " << _offset /*<< " _peekNext: " << _peekNext*/ << " char '" << (char)_char << "'" << endl;
+#endif
+
+#if DEBUG_CARETMODE > 0
+  if (!_end && ebit != (*_it)->end()) {
+    CaretBox *box = *ebit;
+    RenderObject *_r = box->object();
+    kdDebug(6200) << "echit++(1): box " << box << (box && box->isInlineTextBox() ? QString(" contains \"%1\"").arg(QConstString(static_cast<RenderText *>(box->object())->str->s+box->minOffset(), box->maxOffset() - box->minOffset()).string()) : QString::null) << " _r " << (_r ? _r->element()->nodeName().string() : QString("<nil>")) << endl;
+  }
+#endif
+  return *this;
+}
+
+EditableCharacterIterator &EditableCharacterIterator::operator --()
+{
+  _offset--;
+  //kdDebug(6200) << "--: _offset=" << _offset << endl;
+
+  CaretBox *box = *ebit;
+  CaretBox *_peekPrev = 0;
+  CaretBox *_peekNext = 0;
+  InlineBox *b = box->inlineBox();
+  long minofs = box->minOffset();
+#if DEBUG_CARETMODE > 0
+  kdDebug(6200) << "box->maxOffset() " << box->maxOffset() << " box->minOffset() " << box->minOffset() << endl;
+#endif
+  if (_offset == minofs) {
+#if DEBUG_CARETMODE > 2
+kdDebug(6200) << "_offset == minofs: " << _offset << " == " << minofs << endl;
+#endif
+//     _peekNext = b;
+    // get character
+    if (b && !box->isOutside() && b->isInlineTextBox())
+      _char = static_cast<RenderText *>(b->object())->text()[_offset].unicode();
+    else
+      _char = -1;
+
+    //peekPrev();
+    bool do_prev = false;
+    {
+      EditableCaretBoxIterator copy;
+      _peekPrev = 0;
+      do {
+        copy = ebit;
+        --ebit;
+        if (ebit == (*_it)->preBegin()) { ebit = copy; break; }
+      } while (isCaretBoxEmpty(*ebit));
+      // Jump to end of previous element if it's adjacent, and a text box
+      if (ebit.isAdjacent() && ebit != (*_it)->preBegin() && (*ebit)->isInlineTextBox()) {
+        _peekPrev = *ebit;
+	do_prev = true;
+      } else
+        ebit = copy;
+    }
+    if (do_prev) goto prev;
+  } else if (_offset < minofs) {
+prev:
+#if DEBUG_CARETMODE > 2
+kdDebug(6200) << "_offset < minofs: " << _offset << " < " << minofs /*<< " _peekNext: " << _peekNext*/ << endl;
+#endif
+    if (!_peekPrev) {
+      _peekNext = *ebit;
+      --ebit;
+      if (ebit == (*_it)->preBegin()) { // end of line reached, go to previous line
+        --_it;
+#if DEBUG_CARETMODE > 3
+kdDebug(6200) << "--_it" << endl;
+#endif
+        if (_it != _it.lines->preBegin()) {
+// 	  kdDebug(6200) << "begin from end!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!" << endl;
+	  ebit = EditableCaretBoxIterator(_it, true);
+          box = *ebit;
+// 	  RenderObject *r = box->object();
+#if DEBUG_CARETMODE > 3
+kdDebug(6200) << "box " << box << " b " << box->inlineBox() << " isText " << box->isInlineTextBox() << endl;
+#endif
+          _offset = box->maxOffset();
+// 	  if (!_it.outside) _offset = r->isBR() ? (*ebit)->minOffset() : (*ebit)->maxOffset();
+	  _char = -1;
+#if DEBUG_CARETMODE > 0
+          kdDebug(6200) << "echit--(2): box " << box << " b " << box->inlineBox() << (box->isInlineTextBox() ? QString(" contains \"%1\"").arg(QConstString(static_cast<RenderText *>(box->object())->str->s+box->minOffset(), box->maxOffset() - box->minOffset()).string()) : QString::null) << endl;
+#endif
+	} else
+	  _end = true;
+	return *this;
+      }/*end if*/
+    }/*end if*/
+
+#if DEBUG_CARETMODE > 0
+    bool adjacent = ebit.isAdjacent();
+    kdDebug(6200) << "adjacent " << adjacent << " _peekNext " << _peekNext << " _peekNext->isInlineTextBox: " << (_peekNext ? _peekNext->isInlineTextBox() : false) << " !((*ebit)->isInlineTextBox): " << (*ebit ? !(*ebit)->isInlineTextBox() : true) << endl;
+#endif
+#if 0
+    // Ignore this box if it isn't a text box, but the previous box was
+    if (adjacent && _peekNext && _peekNext->isInlineTextBox()
+    	&& !(*ebit)->isInlineTextBox()) {
+      EditableCaretBoxIterator copy = ebit;
+      --ebit;
+      if (ebit == (*_it)->preBegin()) /*adjacent = false;
+      else */ebit = copy;
+    }/*end if*/
+#endif
+#if 0
+    // Jump over empty elements.
+    if (adjacent //&& _peekNext && _peekNext->isInlineTextBox()
+        && !(*ebit)->isInlineTextBox()) {
+      bool noemptybox = true;
+      while (isCaretBoxEmpty(*ebit)) {
+        noemptybox = false;
+        EditableCaretBoxIterator copy = ebit;
+        --ebit;
+        if (ebit == (*_it)->preBegin()) { ebit = copy; break; }
+        else _peekNext = *copy;
+      }
+      if (noemptybox) adjacent = false;
+    }/*end if*/
+#endif
+#if DEBUG_CARETMODE > 0
+    kdDebug(6200) << "(*ebit)->obj " << (*ebit)->object()->renderName() << "[" << (*ebit)->object() << "]" << " minOffset: " << (*ebit)->minOffset() << " maxOffset: " << (*ebit)->maxOffset() << endl;
+#endif
+#if DEBUG_CARETMODE > 3
+    RenderObject *_r = (*ebit)->object();
+kdDebug(6200) << "_r " << _r << ":" << _r->element()->nodeName().string() << endl;
+#endif
+    _offset = (*ebit)->maxOffset();
+//     if (!_it.outside) _offset = (*ebit)->maxOffset()/* - adjacent*/;
+#if DEBUG_CARETMODE > 3
+kdDebug(6200) << "_offset " << _offset << endl;
+#endif
+    _peekPrev = 0;
+  } else {
+#if DEBUG_CARETMODE > 0
+kdDebug(6200) << "_offset: " << _offset << " _peekNext: " << _peekNext << endl;
+#endif
+    // get character
+    if (_peekNext && _offset >= box->maxOffset() && _peekNext->isInlineTextBox())
+      _char = static_cast<RenderText *>(_peekNext->object())->text()[_peekNext->minOffset()].unicode();
+    else if (b && _offset < b->maxOffset() && b->isInlineTextBox())
+      _char = static_cast<RenderText *>(b->object())->text()[_offset].unicode();
+    else
+      _char = -1;
+  }/*end if*/
+
+#if DEBUG_CARETMODE > 0
+  if (!_end && ebit != (*_it)->preBegin()) {
+    CaretBox *box = *ebit;
+    kdDebug(6200) << "echit--(1): box " << box << " b " << box->inlineBox() << (box->isInlineTextBox() ? QString(" contains \"%1\"").arg(QConstString(static_cast<RenderText *>(box->object())->str->s+box->minOffset(), box->maxOffset() - box->minOffset()).string()) : QString::null) << endl;
+  }
+#endif
+  return *this;
+}
+
+// == class TableRowIterator implementation
+
+TableRowIterator::TableRowIterator(RenderTable *table, bool fromEnd,
+  		RenderTableSection::RowStruct *row)
+		: sec(table, fromEnd)
+{
+  // set index
+  if (*sec) {
+    if (fromEnd) index = (*sec)->grid.size() - 1;
+    else index = 0;
+  }/*end if*/
+
+  // initialize with given row
+  if (row && *sec) {
+    while (operator *() != row)
+      if (fromEnd) operator --(); else operator ++();
+  }/*end if*/
+}
+
+TableRowIterator &TableRowIterator::operator ++()
+{
+  index++;
+
+  if (index >= (int)(*sec)->grid.size()) {
+    ++sec;
+
+    if (*sec) index = 0;
+  }/*end if*/
+  return *this;
+}
+
+TableRowIterator &TableRowIterator::operator --()
+{
+  index--;
+
+  if (index < 0) {
+    --sec;
+
+    if (*sec) index = (*sec)->grid.size() - 1;
+  }/*end if*/
+  return *this;
+}
+
+// == class ErgonomicEditableLineIterator implementation
+
+// some decls
+static RenderTableCell *findNearestTableCellInRow(KHTMLPart *part, int x,
+		RenderTableSection::RowStruct *row, bool fromEnd);
+
+/** finds the cell corresponding to absolute x-coordinate @p x in the given
+ * table.
+ *
+ * If there is no direct cell, or the cell is not accessible, the function
+ * will return the nearest suitable cell.
+ * @param part part containing the document
+ * @param x absolute x-coordinate
+ * @param it table row iterator, will be adapted accordingly as more rows are
+ *	investigated.
+ * @param fromEnd @p true to begin search from end and work towards the
+ *	beginning
+ * @return the cell, or 0 if no editable cell was found.
+ */
+static inline RenderTableCell *findNearestTableCell(KHTMLPart *part, int x,
+		TableRowIterator &it, bool fromEnd)
+{
+  RenderTableCell *result = 0;
+
+  while (*it) {
+    result = findNearestTableCellInRow(part, x, *it, fromEnd);
+    if (result) break;
+
+    if (fromEnd) --it; else ++it;
+  }/*wend*/
+
+  return result;
+}
+
+/** finds the nearest editable cell around the given absolute x-coordinate
+ *
+ * It will dive into nested tables as necessary to provide seamless navigation.
+ *
+ * If the cell at @p x is not editable, its left neighbor is tried, then its
+ * right neighbor, then the left neighbor's left neighbor etc. If no
+ * editable cell can be found, 0 is returned.
+ * @param part khtml part
+ * @param x absolute x-coordinate
+ * @param row table row to be searched
+ * @param fromEnd @p true, begin from end (applies only to nested tables)
+ * @return the found cell or 0 if no editable cell was found
+ */
+static RenderTableCell *findNearestTableCellInRow(KHTMLPart *part, int x,
+		RenderTableSection::RowStruct *row, bool fromEnd)
+{
+  // First pass. Find spatially nearest cell.
+  int n = (int)row->row->size();
+  int i;
+  for (i = 0; i < n; i++) {
+    RenderTableCell *cell = row->row->at(i);
+    if (!cell || (long)cell == -1) continue;
+
+    int absx, absy;
+    cell->absolutePosition(absx, absy, false); // ### position: fixed?
+#if DEBUG_CARETMODE > 1
+    kdDebug(6201) << "i/n " << i << "/" << n << " absx " << absx << " absy " << absy << endl;
+#endif
+
+    // I rely on the assumption that all cells are in ascending visual order
+    // ### maybe this assumption is wrong for bidi?
+#if DEBUG_CARETMODE > 1
+    kdDebug(6201) << "x " << x << " < " << (absx + cell->width()) << "?" << endl;
+#endif
+    if (x < absx + cell->width()) break;
+  }/*next i*/
+  if (i >= n) i = n - 1;
+
+  // Second pass. Find editable cell, beginning with the currently found,
+  // extending to the left, and to the right, alternating.
+  for (int cnt = 0; cnt < 2*n; cnt++) {
+    int index = i - ((cnt >> 1) + 1)*(cnt & 1) + (cnt >> 1)*!(cnt & 1);
+    if (index < 0 || index >= n) continue;
+
+    RenderTableCell *cell = row->row->at(index);
+    if (!cell || (long)cell == -1) continue;
+
+#if DEBUG_CARETMODE > 1
+    kdDebug(6201) << "index " << index << " cell " << cell << endl;
+#endif
+    RenderTable *nestedTable;
+    if (containsEditableElement(part, cell, nestedTable, fromEnd)) {
+
+      if (nestedTable) {
+        TableRowIterator it(nestedTable, fromEnd);
+	while (*it) {
+// kdDebug(6201) << "=== recursive invocation" << endl;
+          cell = findNearestTableCell(part, x, it, fromEnd);
+	  if (cell) break;
+	  if (fromEnd) --it; else ++it;
+	}/*wend*/
+      }/*end if*/
+
+      return cell;
+    }/*end if*/
+  }/*next i*/
+  return 0;
+}
+
+/** returns the nearest common ancestor of two objects that is a table cell,
+ * a table section, or 0 if not inside a common table.
+ *
+ * If @p r1 and @p r2 belong to the same table, but different sections, @p r1's
+ * section is returned.
+ */
+static RenderObject *commonAncestorTableSectionOrCell(RenderObject *r1,
+		RenderObject *r2)
+{
+  if (!r1 || !r2) return 0;
+  RenderTableSection *sec = 0;
+  int start_depth=0, end_depth=0;
+  // First we find the depths of the two objects in the tree (start_depth, end_depth)
+  RenderObject *n = r1;
+  while (n->parent()) {
+    n = n->parent();
+    start_depth++;
+  }/*wend*/
+  n = r2;
+  while( n->parent()) {
+    n = n->parent();
+    end_depth++;
+  }/*wend*/
+  // here we climb up the tree with the deeper object, until both objects have equal depth
+  while (end_depth > start_depth) {
+    r2 = r2->parent();
+    end_depth--;
+  }/*wend*/
+  while (start_depth > end_depth) {
+    r1 = r1->parent();
+//    if (r1->isTableSection()) sec = static_cast<RenderTableSection *>(r1);
+    start_depth--;
+  }/*wend*/
+  // Climb the tree with both r1 and r2 until they are the same
+  while (r1 != r2){
+    r1 = r1->parent();
+    if (r1->isTableSection()) sec = static_cast<RenderTableSection *>(r1);
+    r2 = r2->parent();
+  }/*wend*/
+
+  // At this point, we found the most approximate common ancestor. Now climb
+  // up until the condition of the function return value is satisfied.
+  while (r1 && !r1->isTableCell() && !r1->isTableSection() && !r1->isTable())
+    r1 = r1->parent();
+
+  return r1 && r1->isTable() ? sec : r1;
+}
+
+/** Finds the row that contains the given cell, directly, or indirectly
+ * @param section section to be searched
+ * @param cell table cell
+ * @param row returns the row
+ * @param directCell returns the direct cell that contains @p cell
+ * @return the index of the row.
+ */
+static int findRowInSection(RenderTableSection *section, RenderTableCell *cell,
+		RenderTableSection::RowStruct *&row, RenderTableCell *&directCell)
+{
+  // Seek direct cell
+  RenderObject *r = cell;
+  while (r != section) {
+    if (r->isTableCell()) directCell = static_cast<RenderTableCell *>(r);
+    r = r->parent();
+  }/*wend*/
+
+  // So, and this is really nasty: As we have no indices, we have to do a
+  // linear comparison. Oh, that sucks so much for long tables, you can't
+  // imagine.
+  int n = section->numRows();
+  for (int i = 0; i < n; i++) {
+    row = &section->grid[i];
+
+    // check for cell
+    int m = row->row->size();
+    for (int j = 0; j < m; j++) {
+      RenderTableCell *c = row->row->at(j);
+      if (c == directCell) return i;
+    }/*next j*/
+
+  }/*next i*/
+  Q_ASSERT(false);
+  return -1;
+}
+
+/** finds the table that is the first direct or indirect descendant of @p block.
+ * @param leaf object to begin search from.
+ * @param block object to search to, or 0 to search up to top.
+ * @return the table or 0 if there were none.
+ */
+static inline RenderTable *findFirstDescendantTable(RenderObject *leaf, RenderBlock *block)
+{
+  RenderTable *result = 0;
+  while (leaf && leaf != block) {
+    if (leaf->isTable()) result = static_cast<RenderTable *>(leaf);
+    leaf = leaf->parent();
+  }/*wend*/
+  return result;
+}
+
+/** looks for the table cell the given object @p r is contained within.
+ * @return the table cell or 0 if not contained in any table.
+ */
+static inline RenderTableCell *containingTableCell(RenderObject *r)
+{
+  while (r && !r->isTableCell()) r = r->parent();
+  return static_cast<RenderTableCell *>(r);
+}
+
+inline void ErgonomicEditableLineIterator::calcAndStoreNewLine(
+			RenderBlock *newBlock, bool toBegin)
+{
+  // take the first/last editable element in the found cell as the new
+  // value for the iterator
+  CaretBoxIterator it;
+  cbl = CaretBoxLine::constructCaretBoxLine(&lines->cblDeleter,
+  	newBlock, true, toBegin, it);
+#if DEBUG_CARETMODE > 3
+  kdDebug(6201) << cbl->information() << endl;
+#endif
+//  if (toBegin) prevBlock(); else nextBlock();
+
+  if (!cbl) {
+    return;
+  }/*end if*/
+
+  EditableLineIterator::advance(toBegin);
+}
+
+void ErgonomicEditableLineIterator::determineTopologicalElement(
+		RenderTableCell *oldCell, RenderObject *newObject, bool toBegin)
+{
+  // When we arrive here, a transition between cells has happened.
+  // Now determine the type of the transition. This can be
+  // (1) a transition from this cell into a table inside this cell.
+  // (2) a transition from this cell into another cell of this table
+
+  TableRowIterator it;
+
+  RenderObject *commonAncestor = commonAncestorTableSectionOrCell(oldCell, newObject);
+#if DEBUG_CARETMODE > 1
+  kdDebug(6201) << " ancestor " << commonAncestor << endl;
+#endif
+
+  // The whole document is treated as a table cell.
+  if (!commonAncestor || commonAncestor->isTableCell()) {	// (1)
+
+    RenderTableCell *cell = static_cast<RenderTableCell *>(commonAncestor);
+    RenderTable *table = findFirstDescendantTable(newObject, cell);
+
+#if DEBUG_CARETMODE > 0
+    kdDebug(6201) << "table cell: " << cell << endl;
+#endif
+
+    // if there is no table, we fell out of the previous table, and are now
+    // in some table-less block. Therefore, done.
+    if (!table) return;
+
+    it = TableRowIterator(table, toBegin);
+
+  } else if (commonAncestor->isTableSection()) {		// (2)
+
+    RenderTableSection *section = static_cast<RenderTableSection *>(commonAncestor);
+    RenderTableSection::RowStruct *row;
+    int idx = findRowInSection(section, oldCell, row, oldCell);
+#if DEBUG_CARETMODE > 1
+    kdDebug(6201) << "table section: row idx " << idx << endl;
+#endif
+
+    it = TableRowIterator(section, idx);
+
+    // advance rowspan rows
+    int rowspan = oldCell->rowSpan();
+    while (*it && rowspan--) {
+      if (toBegin) --it; else ++it;
+    }/*wend*/
+
+  } else {
+    kdError(6201) << "Neither common cell nor section! " << commonAncestor->renderName() << endl;
+    // will crash on uninitialized table row iterator
+  }/*end if*/
+
+  RenderTableCell *cell = findNearestTableCell(lines->m_part, xCoor, it, toBegin);
+#if DEBUG_CARETMODE > 1
+  kdDebug(6201) << "findNearestTableCell result: " << cell << endl;
+#endif
+
+  RenderBlock *newBlock = cell;
+  if (!cell) {
+    Q_ASSERT(commonAncestor->isTableSection());
+    RenderTableSection *section = static_cast<RenderTableSection *>(commonAncestor);
+    cell = containingTableCell(section);
+#if DEBUG_CARETMODE > 1
+    kdDebug(6201) << "containing cell: " << cell << endl;
+#endif
+
+    RenderTable *nestedTable;
+    bool editableChild = cell && containsEditableChildElement(lines->m_part,
+    		cell, nestedTable, toBegin, section->table());
+
+    if (cell && !editableChild) {
+#if DEBUG_CARETMODE > 1
+      kdDebug(6201) << "========= recursive invocation outer =========" << endl;
+#endif
+      determineTopologicalElement(cell, cell->section(), toBegin);
+#if DEBUG_CARETMODE > 1
+      kdDebug(6201) << "========= end recursive invocation outer =========" << endl;
+#endif
+      return;
+
+    } else if (cell && nestedTable) {
+#if DEBUG_CARETMODE > 1
+      kdDebug(6201) << "========= recursive invocation inner =========" << endl;
+#endif
+      determineTopologicalElement(cell, nestedTable, toBegin);
+#if DEBUG_CARETMODE > 1
+      kdDebug(6201) << "========= end recursive invocation inner =========" << endl;
+#endif
+      return;
+
+    } else {
+#if DEBUG_CARETMODE > 1
+      kdDebug(6201) << "newBlock is table: " << section->table() << endl;
+#endif
+      RenderObject *r = section->table();
+      int state;		// not used
+      ObjectTraversalState trav = OutsideAscending;
+      r = advanceSuitableObject(r, trav, toBegin, lines->baseObject(), state);
+      if (!r) { cbl = 0;  return; }
+//      if (toBegin) prevBlock(); else nextBlock();
+      newBlock = static_cast<RenderBlock *>(!r || r->isRenderBlock() ? r : r->containingBlock());
+    }/*end if*/
+#if 0
+  } else {
+    // adapt cell so that prevBlock/nextBlock works as expected
+    newBlock = cell;
+    // on forward advancing, we must start from the outside end of the
+    // previous object
+    if (!toBegin) {
+      RenderObject *r = newBlock;
+      int state;		// not used
+      ObjectTraversalState trav = OutsideAscending;
+      r = advanceSuitableObject(r, trav, true, lines->advancePolicy(), lines->baseObject(), state);
+      newBlock = static_cast<RenderBlock *>(!r || r->isRenderBlock() ? r : r->containingBlock());
+    }/*end if*/
+#endif
+  }/*end if*/
+
+  calcAndStoreNewLine(newBlock, toBegin);
+}
+
+ErgonomicEditableLineIterator &ErgonomicEditableLineIterator::operator ++()
+{
+  RenderTableCell *oldCell = containingTableCell(cbl->enclosingObject());
+
+  EditableLineIterator::operator ++();
+  if (*this == lines->end() || *this == lines->preBegin()) return *this;
+
+  RenderTableCell *newCell = containingTableCell(cbl->enclosingObject());
+
+  if (!newCell || newCell == oldCell) return *this;
+
+  determineTopologicalElement(oldCell, newCell, false);
+
+  return *this;
+}
+
+ErgonomicEditableLineIterator &ErgonomicEditableLineIterator::operator --()
+{
+  RenderTableCell *oldCell = containingTableCell(cbl->enclosingObject());
+
+  EditableLineIterator::operator --();
+  if (*this == lines->end() || *this == lines->preBegin()) return *this;
+
+  RenderTableCell *newCell = containingTableCell(cbl->enclosingObject());
+
+  if (!newCell || newCell == oldCell) return *this;
+
+  determineTopologicalElement(oldCell, newCell, true);
+
+  return *this;
+}
+
+// == Navigational helper functions ==
+
+/** seeks the caret box which contains or is the nearest to @p x
+ * @param it line iterator pointing to line to be searched
+ * @param cv caret view context
+ * @param x returns the cv->origX approximation, relatively positioned to the
+ *	containing block.
+ * @param absx returns absolute x-coordinate of containing block
+ * @param absy returns absolute y-coordinate of containing block
+ * @return the most suitable caret box
+ */
+static CaretBox *nearestCaretBox(LineIterator &it, CaretViewContext *cv,
+	int &x, int &absx, int &absy)
+{
+  // Find containing block
+  RenderObject *cb = (*it)->containingBlock();
+#if DEBUG_CARETMODE > 4
+  kdDebug(6200) << "nearestCB: cb " << cb << "@" << (cb ? cb->renderName() : "") << endl;
+#endif
+
+  if (cb) cb->absolutePosition(absx, absy);
+  else absx = absy = 0;
+
+  // Otherwise find out in which inline box the caret is to be placed.
+
+  // this horizontal position is to be approximated
+  x = cv->origX - absx;
+  CaretBox *caretBox = 0; // Inline box containing the caret
+//  NodeImpl *lastnode = 0;  // node of previously checked render object.
+  int xPos;		   // x-coordinate of current inline box
+  int oldXPos = -1;	   // x-coordinate of last inline box
+  EditableCaretBoxIterator fbit = it;
+#if DEBUG_CARETMODE > 0
+/*  if (it.linearDocument()->advancePolicy() != LeafsOnly)
+    kdWarning() << "nearestInlineBox is only prepared to handle the LeafsOnly advance policy" << endl;*/
+//   kdDebug(6200) << "*fbit = " << *fbit << endl;
+#endif
+  // Iterate through all children
+  for (CaretBox *b; fbit != (*it)->end(); ++fbit) {
+    b = *fbit;
+
+#if DEBUG_CARETMODE > 0
+//    RenderObject *r = b->object();
+//	if (b->isInlineFlowBox()) kdDebug(6200) << "b is inline flow box" << endl;
+//	kdDebug(6200) << "approximate r" << r << ": " << (r ? r->renderName() : QString::null) << (r && r->isText() ? " contains \"" + QString(((RenderText *)r)->str->s, ((RenderText *)r)->str->l) + "\"" : QString::null) << endl;
+#endif
+    xPos = b->xPos();
+
+    // the caret is before this box
+    if (x < xPos) {
+      // snap to nearest box
+      if (oldXPos < 0 || x - (oldXPos + caretBox->width()) > xPos - x) {
+	caretBox = b;	// current box is nearer
+      }/*end if*/
+      break;		// Otherwise, preceding box is implicitly used
+    }
+
+    caretBox = b;
+
+    // the caret is within this box
+    if (x >= xPos && x < xPos + caretBox->width())
+      break;
+    oldXPos = xPos;
+
+    // the caret can only be after the last box which is automatically
+    // contained in caretBox when we fall out of the loop.
+  }/*next fbit*/
+
+  return caretBox;
+}
+
+/** moves the given iterator to the beginning of the next word.
+ *
+ * If the end is reached, the iterator will be positioned there.
+ * @param it character iterator to be moved
+ */
+static void moveItToNextWord(EditableCharacterIterator &it)
+{
+#if DEBUG_CARETMODE > 0
+  kdDebug(6200) << "%%%%%%%%%%%%%%%%%%%%% moveItToNextWord" << endl;
+#endif
+  EditableCharacterIterator copy;
+  while (!it.isEnd() && !(*it).isSpace() && !(*it).isPunct()) {
+#if DEBUG_CARETMODE > 2
+    kdDebug(6200) << "reading1 '" << (*it).latin1() << "'" << endl;
+#endif
+    copy = it;
+    ++it;
+  }
+
+  if (it.isEnd()) {
+    it = copy;
+    return;
+  }/*end if*/
+
+  while (!it.isEnd() && ((*it).isSpace() || (*it).isPunct())) {
+#if DEBUG_CARETMODE > 2
+    kdDebug(6200) << "reading2 '" << (*it).latin1() << "'" << endl;
+#endif
+    copy = it;
+    ++it;
+  }
+
+  if (it.isEnd()) it = copy;
+}
+
+/** moves the given iterator to the beginning of the previous word.
+ *
+ * If the beginning is reached, the iterator will be positioned there.
+ * @param it character iterator to be moved
+ */
+static void moveItToPrevWord(EditableCharacterIterator &it)
+{
+  if (it.isEnd()) return;
+
+#if DEBUG_CARETMODE > 0
+  kdDebug(6200) << "%%%%%%%%%%%%%%%%%%%%% moveItToPrevWord" << endl;
+#endif
+  EditableCharacterIterator copy;
+
+  // Jump over all space and punctuation characters first
+  do {
+    copy = it;
+    --it;
+#if DEBUG_CARETMODE > 2
+    if (!it.isEnd()) kdDebug(6200) << "reading1 '" << (*it).latin1() << "'" << endl;
+#endif
+  } while (!it.isEnd() && ((*it).isSpace() || (*it).isPunct()));
+
+  if (it.isEnd()) {
+    it = copy;
+    return;
+  }/*end if*/
+
+  do {
+    copy = it;
+    --it;
+#if DEBUG_CARETMODE > 0
+    if (!it.isEnd()) kdDebug(6200) << "reading2 '" << (*it).latin1() << "' (" << (int)(*it).latin1() << ") box " << it.caretBox() << endl;
+#endif
+  } while (!it.isEnd() && !(*it).isSpace() && !(*it).isPunct());
+
+  it = copy;
+#if DEBUG_CARETMODE > 1
+    if (!it.isEnd()) kdDebug(6200) << "effective '" << (*it).latin1() << "' (" << (int)(*it).latin1() << ") box " << it.caretBox() << endl;
+#endif
+}
+
+/** moves the iterator by one page.
+ * @param ld linear document
+ * @param it line iterator, will be updated accordingly
+ * @param mindist minimum distance in pixel the iterator should be moved
+ *	(if possible)
+ * @param next @p true, move downward, @p false move upward
+ */
+static void moveIteratorByPage(LinearDocument &ld,
+		ErgonomicEditableLineIterator &it, int mindist, bool next)
+{
+  // ### This whole routine plainly sucks. Use an inverse strategie for pgup/pgdn.
+
+  if (it == ld.end() || it == ld.preBegin()) return;
+
+  ErgonomicEditableLineIterator copy = it;
+#if DEBUG_CARETMODE > 0
+  kdDebug(6200) << " mindist: " << mindist << endl;
+#endif
+
+  CaretBoxLine *cbl = *copy;
+  int absx = 0, absy = 0;
+
+  RenderBlock *lastcb = cbl->containingBlock();
+  Q_ASSERT(lastcb->isRenderBlock());
+  lastcb->absolutePosition(absx, absy, false);	// ### what about fixed?
+
+  int lastfby = cbl->begin().data()->yPos();
+  int lastheight = 0;
+  int rescue = 1000;	// ### this is a hack to keep stuck carets from hanging the ua
+  do {
+    if (next) ++copy; else --copy;
+    if (copy == ld.end() || copy == ld.preBegin()) break;
+
+    cbl = *copy;
+    RenderBlock *cb = cbl->containingBlock();
+
+    int diff = 0;
+    // ### actually flowBox->yPos() should suffice, but this is not ported
+    // over yet from WebCore
+    int fby = cbl->begin().data()->yPos();
+    if (cb != lastcb) {
+      if (next) {
+        diff = absy + lastfby + lastheight;
+        cb->absolutePosition(absx, absy, false);	// ### what about fixed?
+        diff = absy - diff + fby;
+        lastfby = 0;
+      } else {
+        diff = absy;
+        cb->absolutePosition(absx, absy, false);	// ### what about fixed?
+        diff -= absy + fby + lastheight;
+	lastfby = fby - lastheight;
+      }/*end if*/
+#if DEBUG_CARETMODE > 2
+      kdDebug(6200) << "absdiff " << diff << endl;
+#endif
+    } else {
+      diff = kAbs(fby - lastfby);
+    }/*end if*/
+#if DEBUG_CARETMODE > 2
+    kdDebug(6200) << "cbl->begin().data()->yPos(): " << fby << " diff " << diff << endl;
+#endif
+
+    mindist -= diff;
+
+    lastheight = kAbs(fby - lastfby);
+    lastfby = fby;
+    lastcb = cb;
+    it = copy;
+#if DEBUG_CARETMODE > 0
+    kdDebug(6200) << " mindist: " << mindist << endl;
+#endif
+    // trick: actually the distance is always one line short, but we cannot
+    // calculate the height of the first line (### WebCore will make it better)
+    // Therefore, we simply approximate that excess line by using the last
+    // caluculated line height.
+  } while (mindist - lastheight > 0 && --rescue);
+}
+
+
+}/*end namespace*/