Bug 84645. Move XBL insertion point logic into nsCSSFrameConstructor, where it can interact nicely with continuing frames. r=dbaron, sr=hyatt

git-svn-id: svn://10.0.0.236/trunk@102820 18797224-902f-48f8-a5cc-f745e15eee43

mozilla/layout/base/nsFrameContentIterator.cpp

@@ -0,0 +1,316 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*-
+ *
+ * The contents of this file are subject to the Mozilla Public License
+ * Version 1.1 (the "MPL"); you may not use this file except in
+ * compliance with the MPL.  You may obtain a copy of the MPL at
+ * http://www.mozilla.org/MPL/
+ *
+ * Software distributed under the MPL is distributed on an "AS IS" basis,
+ * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the MPL
+ * for the specific language governing rights and limitations under the
+ * MPL.
+ *
+ * The Initial Developer of this code under the MPL is Netscape
+ * Communications Corporation.  Portions created by Netscape are
+ * Copyright (C) 2000 Netscape Communications Corporation.  All Rights
+ * Reserved.
+ */
+
+#include "nsCOMPtr.h"
+#include "nsIContentIterator.h"
+#include "nsIPresContext.h"
+#include "nsIFrame.h"
+#include "nsIContent.h"
+#include "nsIEnumerator.h"
+#include "nsFrameList.h"
+
+class nsFrameContentIterator : public nsIContentIterator
+{
+public:
+  nsFrameContentIterator(nsIPresContext* aPresContext, nsIFrame* aFrame);
+  virtual ~nsFrameContentIterator();
+
+  // nsISupports
+  NS_DECL_ISUPPORTS
+
+  // nsIContentIterator
+  NS_IMETHOD Init(nsIContent* aRoot);
+  NS_IMETHOD Init(nsIDOMRange* aRange);
+  
+  NS_IMETHOD First();
+  NS_IMETHOD Last();
+  NS_IMETHOD Next();
+  NS_IMETHOD Prev();
+
+  NS_IMETHOD CurrentNode(nsIContent **aNode);
+  NS_IMETHOD IsDone();
+  NS_IMETHOD PositionAt(nsIContent* aCurNode);
+
+  NS_IMETHOD MakePre();
+  NS_IMETHOD MakePost();
+
+private:
+  nsCOMPtr<nsIPresContext>  mPresContext;
+  nsIFrame*                 mParentFrame;
+  nsIFrame*                 mCurrentChild;
+  PRBool                    mIsDone;
+};
+
+nsFrameContentIterator::nsFrameContentIterator(nsIPresContext* aPresContext,
+                                                   nsIFrame*       aFrame)
+  : mPresContext(aPresContext), mParentFrame(aFrame), mIsDone(PR_FALSE)
+{
+  NS_INIT_REFCNT();
+  First();
+}
+
+NS_IMPL_ISUPPORTS1(nsFrameContentIterator, nsIContentIterator);
+
+nsFrameContentIterator::~nsFrameContentIterator()
+{
+}
+
+NS_IMETHODIMP
+nsFrameContentIterator::Init(nsIContent* aRoot)
+{
+  return NS_ERROR_ALREADY_INITIALIZED;
+}
+
+NS_IMETHODIMP
+nsFrameContentIterator::Init(nsIDOMRange* aRange)
+{
+  return NS_ERROR_ALREADY_INITIALIZED;
+}
+
+NS_IMETHODIMP
+nsFrameContentIterator::First()
+{
+  // Get the first child frame and make it the current node
+  mParentFrame->FirstChild(mPresContext, nsnull, &mCurrentChild);
+  if (!mCurrentChild) {
+    return NS_ERROR_FAILURE;
+  }
+  mIsDone = PR_FALSE;
+  return NS_OK;
+}
+
+
+static nsIFrame*
+GetNextChildFrame(nsIPresContext* aPresContext, nsIFrame* aFrame)
+{
+  NS_PRECONDITION(aFrame, "null pointer");
+
+  // Get the last-in-flow
+  while (PR_TRUE) {
+    nsIFrame* nextInFlow;
+    aFrame->GetNextInFlow(&nextInFlow);
+    if (nextInFlow) {
+      aFrame = nextInFlow;
+    } else {
+      break;
+    }
+  }
+
+  // Get its next sibling
+  nsIFrame* nextSibling;
+  aFrame->GetNextSibling(&nextSibling);
+
+  // If there's no next sibling, then check if the parent frame
+  // has a next-in-flow and look there
+  if (!nextSibling) {
+    nsIFrame* parent;
+    aFrame->GetParent(&parent);
+    parent->GetNextInFlow(&parent);
+
+    if (parent) {
+      parent->FirstChild(aPresContext, nsnull, &nextSibling);
+    }
+  }
+
+  return nextSibling;
+}
+
+NS_IMETHODIMP
+nsFrameContentIterator::Last()
+{
+  nsIFrame* nextChild;
+
+  // Starting with the first child walk and find the last child
+  mCurrentChild = nsnull;
+  mParentFrame->FirstChild(mPresContext, nsnull, &nextChild);
+  while (nextChild) {
+    mCurrentChild = nextChild;
+    nextChild = ::GetNextChildFrame(mPresContext, nextChild);
+  }
+
+  if (!mCurrentChild) {
+    return NS_ERROR_FAILURE;
+  }
+  mIsDone = PR_FALSE;
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsFrameContentIterator::Next()
+{
+  nsIFrame* nextChild = ::GetNextChildFrame(mPresContext, mCurrentChild);
+
+  if (nextChild) {
+    // Advance to the next child
+    mCurrentChild = nextChild;
+
+    // If we're at the end then the collection is at the end
+    mIsDone = (nsnull == ::GetNextChildFrame(mPresContext, mCurrentChild));
+    return NS_OK;
+  }
+
+  return NS_ERROR_FAILURE;
+}
+
+static nsIFrame*
+GetPrevChildFrame(nsIPresContext* aPresContext, nsIFrame* aFrame)
+{
+  NS_PRECONDITION(aFrame, "null pointer");
+
+  // Get its previous sibling. Because we have a singly linked list we
+  // need to search from the first child
+  nsIFrame* parent;
+  nsIFrame* firstChild;
+  nsIFrame* prevSibling;
+
+  aFrame->GetParent(&parent);
+  parent->FirstChild(aPresContext, nsnull, &firstChild);
+
+  NS_ASSERTION(firstChild, "parent has no first child");
+  nsFrameList frameList(firstChild);
+  prevSibling = frameList.GetPrevSiblingFor(aFrame);
+
+  // If there's no previous sibling, then check if the parent frame
+  // has a prev-in-flow and look there
+  if (!prevSibling) {
+    parent->GetPrevInFlow(&parent);
+
+    if (parent) {
+      parent->FirstChild(aPresContext, nsnull, &firstChild);
+      frameList.SetFrames(firstChild);
+      prevSibling = frameList.LastChild();
+    }
+  }
+  
+  // Get the first-in-flow
+  while (PR_TRUE) {
+    nsIFrame* prevInFlow;
+    prevSibling->GetPrevInFlow(&prevInFlow);
+    if (prevInFlow) {
+      prevSibling = prevInFlow;
+    } else {
+      break;
+    }
+  }
+
+  return prevSibling;
+}
+
+NS_IMETHODIMP
+nsFrameContentIterator::Prev()
+{
+  nsIFrame* prevChild = ::GetPrevChildFrame(mPresContext, mCurrentChild);
+
+  if (prevChild) {
+    // Make the previous child the current child
+    mCurrentChild = prevChild;
+    
+    // If we're at the beginning then the collection is at the end
+    mIsDone = (nsnull == ::GetPrevChildFrame(mPresContext, mCurrentChild));
+    return NS_OK;
+  }
+
+  return NS_ERROR_FAILURE;
+}
+
+NS_IMETHODIMP
+nsFrameContentIterator::CurrentNode(nsIContent **aNode)
+{
+  if (mCurrentChild) {
+    mCurrentChild->GetContent(aNode);
+    return NS_OK;
+
+  } else {
+    *aNode = nsnull;
+    return NS_ERROR_FAILURE;
+  }
+}
+
+NS_IMETHODIMP
+nsFrameContentIterator::IsDone()
+{
+  return mIsDone ? NS_OK : NS_ENUMERATOR_FALSE;
+}
+
+NS_IMETHODIMP
+nsFrameContentIterator::PositionAt(nsIContent* aCurNode)
+{
+  nsIFrame* child;
+
+  // Starting with the first child frame search for the child frame
+  // with the matching content object
+  mParentFrame->FirstChild(mPresContext, nsnull, &child);
+  while (child) {
+    nsCOMPtr<nsIContent>  content;
+
+    child->GetContent(getter_AddRefs(content));
+    if (content.get() == aCurNode) {
+      break;
+    }
+    child = ::GetNextChildFrame(mPresContext, child);
+  }
+
+  if (child) {
+    // Make it the current child
+    mCurrentChild = child;
+    mIsDone = PR_FALSE;
+    return NS_OK;
+  }
+
+  return NS_ERROR_FAILURE;
+}
+
+NS_IMETHODIMP
+nsFrameContentIterator::MakePre()
+{
+  return NS_ERROR_NOT_IMPLEMENTED;
+}
+
+NS_IMETHODIMP
+nsFrameContentIterator::MakePost()
+{
+  return NS_ERROR_NOT_IMPLEMENTED;
+}
+
+nsresult
+NS_NewFrameContentIterator(nsIPresContext*      aPresContext,
+                           nsIFrame*            aFrame,
+                           nsIContentIterator** aIterator)
+{
+  NS_ENSURE_ARG_POINTER(aIterator);
+  if (!aIterator) {
+    return NS_ERROR_NULL_POINTER;
+  }
+  NS_ENSURE_ARG_POINTER(aFrame);
+  if (!aFrame) {
+    return NS_ERROR_NULL_POINTER;
+  }
+  
+  // Make sure the frame corresponds to generated content
+#ifdef DEBUG
+  nsFrameState  frameState;
+  aFrame->GetFrameState(&frameState);
+  NS_ASSERTION(frameState & NS_FRAME_GENERATED_CONTENT, "unexpected frame");
+#endif
+
+  nsFrameContentIterator* it = new nsFrameContentIterator(aPresContext, aFrame);
+  if (!it) {
+    return NS_ERROR_OUT_OF_MEMORY;
+  }
+  return it->QueryInterface(NS_GET_IID(nsIContentIterator), (void **)aIterator);
+}