gecko-dev/editor/base/PlaceholderTxn.cpp

287 строки
8.7 KiB
C++

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
*
* The contents of this file are subject to the Netscape Public
* License Version 1.1 (the "License"); you may not use this file
* except in compliance with the License. You may obtain a copy of
* the License at http://www.mozilla.org/NPL/
*
* Software distributed under the License is distributed on an "AS
* IS" basis, WITHOUT WARRANTY OF ANY KIND, either express or
* implied. See the License for the specific language governing
* rights and limitations under the License.
*
* The Original Code is mozilla.org code.
*
* The Initial Developer of the Original Code is Netscape
* Communications Corporation. Portions created by Netscape are
* Copyright (C) 1998-1999 Netscape Communications Corporation. All
* Rights Reserved.
*
* Contributor(s):
* Pierre Phaneuf <pp@ludusdesign.com>
*/
#include "PlaceholderTxn.h"
#include "nsVoidArray.h"
#include "nsHTMLEditor.h"
#include "nsIPresShell.h"
#include "IMETextTxn.h"
#if defined(NS_DEBUG) && defined(DEBUG_buster)
static PRBool gNoisy = PR_TRUE;
#else
static const PRBool gNoisy = PR_FALSE;
#endif
PlaceholderTxn::PlaceholderTxn() : EditAggregateTxn(),
mPresShellWeak(nsnull),
mAbsorb(PR_TRUE),
mForwarding(nsnull),
mIMETextTxn(nsnull),
mCommitted(PR_FALSE),
mStartSel(nsnull),
mEndSel()
{
SetTransactionDescriptionID( kTransactionID );
/* log description initialized in parent constructor */
}
PlaceholderTxn::~PlaceholderTxn()
{
delete mStartSel;
}
NS_IMPL_ADDREF_INHERITED(PlaceholderTxn, EditAggregateTxn)
NS_IMPL_RELEASE_INHERITED(PlaceholderTxn, EditAggregateTxn)
//NS_IMPL_QUERY_INTERFACE_INHERITED(Class, Super, AdditionalInterface)
NS_IMETHODIMP PlaceholderTxn::QueryInterface(REFNSIID aIID, void** aInstancePtr)
{
if (!aInstancePtr) return NS_ERROR_NULL_POINTER;
if (aIID.Equals(NS_GET_IID(nsIAbsorbingTransaction))) {
*aInstancePtr = (nsISupports*)(nsIAbsorbingTransaction*)(this);
NS_ADDREF_THIS();
return NS_OK;
}
if (aIID.Equals(NS_GET_IID(nsISupportsWeakReference))) {
*aInstancePtr = (nsISupports*)(nsISupportsWeakReference*) this;
NS_ADDREF_THIS();
return NS_OK;
}
return EditAggregateTxn::QueryInterface(aIID, aInstancePtr);
}
NS_IMETHODIMP PlaceholderTxn::Init(nsWeakPtr aPresShellWeak, nsIAtom *aName,
nsSelectionState *aSelState)
{
NS_ASSERTION(aPresShellWeak, "bad args");
if (!aPresShellWeak || !aSelState) return NS_ERROR_NULL_POINTER;
mPresShellWeak = aPresShellWeak;
mName = aName;
mStartSel = aSelState;
return NS_OK;
}
NS_IMETHODIMP PlaceholderTxn::Do(void)
{
if (gNoisy) { printf("PlaceholderTxn Do\n"); }
return NS_OK;
}
NS_IMETHODIMP PlaceholderTxn::Undo(void)
{
// undo txns
nsresult res = EditAggregateTxn::Undo();
if (NS_FAILED(res)) return res;
// now restore selection
nsCOMPtr<nsIPresShell> ps = do_QueryReferent(mPresShellWeak);
if (!ps) return NS_ERROR_NOT_INITIALIZED;
nsCOMPtr<nsIDOMSelection> selection;
res = ps->GetSelection(SELECTION_NORMAL, getter_AddRefs(selection));
if (NS_FAILED(res)) return res;
if (!selection) return NS_ERROR_NULL_POINTER;
if (!mStartSel) return NS_ERROR_NULL_POINTER;
res = mStartSel->RestoreSelection(selection);
return res;
}
NS_IMETHODIMP PlaceholderTxn::Redo(void)
{
// redo txns
nsresult res = EditAggregateTxn::Redo();
if (NS_FAILED(res)) return res;
// now restore selection
nsCOMPtr<nsIPresShell> ps = do_QueryReferent(mPresShellWeak);
if (!ps) return NS_ERROR_NOT_INITIALIZED;
nsCOMPtr<nsIDOMSelection> selection;
res = ps->GetSelection(SELECTION_NORMAL, getter_AddRefs(selection));
if (NS_FAILED(res)) return res;
if (!selection) return NS_ERROR_NULL_POINTER;
res = mEndSel.RestoreSelection(selection);
return res;
}
NS_IMETHODIMP PlaceholderTxn::Merge(PRBool *aDidMerge, nsITransaction *aTransaction)
{
if (!aDidMerge || !aTransaction) return NS_ERROR_NULL_POINTER;
// set out param default value
*aDidMerge=PR_FALSE;
nsresult res = NS_OK;
if (mForwarding)
{
NS_NOTREACHED("tried to merge into a placeholder that was in forwarding mode!");
return NS_ERROR_FAILURE;
}
EditTxn *editTxn = (EditTxn*)aTransaction; //XXX: hack, not safe! need nsIEditTransaction!
if (PR_TRUE==mAbsorb)
{ // yep, it's one of ours. Assimilate it.
IMETextTxn* otherTxn = nsnull;
if (NS_SUCCEEDED(aTransaction->QueryInterface(IMETextTxn::GetCID(),(void**)&otherTxn)) && otherTxn)
{
// special handling for IMETextTxn's: they need to merge with any previous
// IMETextTxn in this placeholder, if possible.
if (!mIMETextTxn)
{
// this is the first IME txn in the placeholder
mIMETextTxn =otherTxn;
AppendChild(editTxn);
}
else
{
PRBool didMerge;
mIMETextTxn->Merge(&didMerge, otherTxn);
if (!didMerge)
{
// it wouldn't merge. Earlier IME txn is already commited and will
// not absorb frther IME txns. So just stack this one after it
// and remember it as a candidate for furthre merges.
mIMETextTxn =otherTxn;
AppendChild(editTxn);
}
}
NS_IF_RELEASE(otherTxn);
}
else
{
AppendChild(editTxn);
}
*aDidMerge = PR_TRUE;
// RememberEndingSelection();
// efficiency hack: no need to remember selection here, as we haven't yet
// finished the inital batch and we know we will be told when the batch ends.
// we can remeber the selection then.
if (gNoisy) { printf("Placeholder txn assimilated %p\n", aTransaction); }
}
else
{ // merge typing or IME or deletion transactions if the selection matches
if (((mName.get() == nsHTMLEditor::gTypingTxnName) ||
(mName.get() == nsHTMLEditor::gIMETxnName) ||
(mName.get() == nsHTMLEditor::gDeleteTxnName))
&& !mCommitted )
{
// but only if this placeholder started with a collapsed selection
if (mStartSel->IsCollapsed())
{
nsCOMPtr<nsIAbsorbingTransaction> plcTxn;// = do_QueryInterface(editTxn);
// cant do_QueryInterface() above due to our broken transaction interfaces.
// instead have to brute it below. ugh.
editTxn->QueryInterface(NS_GET_IID(nsIAbsorbingTransaction), getter_AddRefs(plcTxn));
if (plcTxn)
{
nsCOMPtr<nsIAtom> atom;
plcTxn->GetTxnName(getter_AddRefs(atom));
if (atom && (atom == mName))
{
// check if start selection of next placeholder matches
// end selection of this placeholder
PRBool isSame;
plcTxn->StartSelectionEquals(&mEndSel, &isSame);
if (isSame)
{
mAbsorb = PR_TRUE; // we need to start absorbing again
plcTxn->ForwardEndBatchTo(this);
AppendChild(editTxn);
RememberEndingSelection();
*aDidMerge = PR_TRUE;
}
}
}
}
}
}
return res;
}
NS_IMETHODIMP PlaceholderTxn::GetTxnName(nsIAtom **aName)
{
return GetName(aName);
}
NS_IMETHODIMP PlaceholderTxn::StartSelectionEquals(nsSelectionState *aSelState, PRBool *aResult)
{
// determine if starting selection matches the given selection state.
// note that we only care about collapsed selections.
if (!aResult || !aSelState) return NS_ERROR_NULL_POINTER;
if (!mStartSel->IsCollapsed() || !aSelState->IsCollapsed())
{
*aResult = PR_FALSE;
return NS_OK;
}
*aResult = mStartSel->IsEqual(aSelState);
return NS_OK;
}
NS_IMETHODIMP PlaceholderTxn::EndPlaceHolderBatch()
{
mAbsorb = PR_FALSE;
if (mForwarding)
{
nsCOMPtr<nsIAbsorbingTransaction> plcTxn = do_QueryReferent(mForwarding);
if (plcTxn) plcTxn->EndPlaceHolderBatch();
}
// remember our selection state.
return RememberEndingSelection();
};
NS_IMETHODIMP PlaceholderTxn::ForwardEndBatchTo(nsIAbsorbingTransaction *aForwardingAddress)
{
mForwarding = getter_AddRefs( NS_GetWeakReference(aForwardingAddress) );
return NS_OK;
}
NS_IMETHODIMP PlaceholderTxn::Commit()
{
mCommitted = PR_TRUE;
return NS_OK;
}
NS_IMETHODIMP PlaceholderTxn::RememberEndingSelection()
{
nsCOMPtr<nsIPresShell> ps = do_QueryReferent(mPresShellWeak);
if (!ps) return NS_ERROR_NOT_INITIALIZED;
nsCOMPtr<nsIDOMSelection> selection;
nsresult res = ps->GetSelection(SELECTION_NORMAL, getter_AddRefs(selection));
if (NS_FAILED(res)) return res;
if (!selection) return NS_ERROR_NULL_POINTER;
res = mEndSel.SaveSelection(selection);
return res;
}