1 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
2 /* This Source Code Form is subject to the terms of the Mozilla Public
3 * License, v. 2.0. If a copy of the MPL was not distributed with this
4 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
5
6 #include "PlaceholderTransaction.h"
7
8 #include "CompositionTransaction.h"
9 #include "mozilla/EditorBase.h"
10 #include "mozilla/dom/Selection.h"
11 #include "nsGkAtoms.h"
12 #include "nsQueryObject.h"
13
14 namespace mozilla {
15
16 using namespace dom;
17
PlaceholderTransaction()18 PlaceholderTransaction::PlaceholderTransaction()
19 : mAbsorb(true)
20 , mForwarding(nullptr)
21 , mCompositionTransaction(nullptr)
22 , mCommitted(false)
23 , mEditorBase(nullptr)
24 {
25 }
26
~PlaceholderTransaction()27 PlaceholderTransaction::~PlaceholderTransaction()
28 {
29 }
30
31 NS_IMPL_CYCLE_COLLECTION_CLASS(PlaceholderTransaction)
32
33 NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN_INHERITED(PlaceholderTransaction,
34 EditAggregateTransaction)
35 if (tmp->mStartSel) {
36 ImplCycleCollectionUnlink(*tmp->mStartSel);
37 }
38 NS_IMPL_CYCLE_COLLECTION_UNLINK(mEndSel);
39 NS_IMPL_CYCLE_COLLECTION_UNLINK_END
40
41 NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN_INHERITED(PlaceholderTransaction,
42 EditAggregateTransaction)
43 if (tmp->mStartSel) {
44 ImplCycleCollectionTraverse(cb, *tmp->mStartSel, "mStartSel", 0);
45 }
46 NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mEndSel);
47 NS_IMPL_CYCLE_COLLECTION_TRAVERSE_END
48
NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(PlaceholderTransaction)49 NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(PlaceholderTransaction)
50 NS_INTERFACE_MAP_ENTRY(nsIAbsorbingTransaction)
51 NS_INTERFACE_MAP_ENTRY(nsISupportsWeakReference)
52 NS_INTERFACE_MAP_END_INHERITING(EditAggregateTransaction)
53
54 NS_IMPL_ADDREF_INHERITED(PlaceholderTransaction, EditAggregateTransaction)
55 NS_IMPL_RELEASE_INHERITED(PlaceholderTransaction, EditAggregateTransaction)
56
57 NS_IMETHODIMP
58 PlaceholderTransaction::Init(nsIAtom* aName,
59 SelectionState* aSelState,
60 EditorBase* aEditorBase)
61 {
62 NS_ENSURE_TRUE(aEditorBase && aSelState, NS_ERROR_NULL_POINTER);
63
64 mName = aName;
65 mStartSel = aSelState;
66 mEditorBase = aEditorBase;
67 return NS_OK;
68 }
69
70 NS_IMETHODIMP
DoTransaction()71 PlaceholderTransaction::DoTransaction()
72 {
73 return NS_OK;
74 }
75
76 NS_IMETHODIMP
UndoTransaction()77 PlaceholderTransaction::UndoTransaction()
78 {
79 // Undo transactions.
80 nsresult rv = EditAggregateTransaction::UndoTransaction();
81 NS_ENSURE_SUCCESS(rv, rv);
82
83 NS_ENSURE_TRUE(mStartSel, NS_ERROR_NULL_POINTER);
84
85 // now restore selection
86 RefPtr<Selection> selection = mEditorBase->GetSelection();
87 NS_ENSURE_TRUE(selection, NS_ERROR_NULL_POINTER);
88 return mStartSel->RestoreSelection(selection);
89 }
90
91 NS_IMETHODIMP
RedoTransaction()92 PlaceholderTransaction::RedoTransaction()
93 {
94 // Redo transactions.
95 nsresult rv = EditAggregateTransaction::RedoTransaction();
96 NS_ENSURE_SUCCESS(rv, rv);
97
98 // now restore selection
99 RefPtr<Selection> selection = mEditorBase->GetSelection();
100 NS_ENSURE_TRUE(selection, NS_ERROR_NULL_POINTER);
101 return mEndSel.RestoreSelection(selection);
102 }
103
104
105 NS_IMETHODIMP
Merge(nsITransaction * aTransaction,bool * aDidMerge)106 PlaceholderTransaction::Merge(nsITransaction* aTransaction,
107 bool* aDidMerge)
108 {
109 NS_ENSURE_TRUE(aDidMerge && aTransaction, NS_ERROR_NULL_POINTER);
110
111 // set out param default value
112 *aDidMerge=false;
113
114 if (mForwarding) {
115 NS_NOTREACHED("tried to merge into a placeholder that was in forwarding mode!");
116 return NS_ERROR_FAILURE;
117 }
118
119 // check to see if aTransaction is one of the editor's
120 // private transactions. If not, we want to avoid merging
121 // the foreign transaction into our placeholder since we
122 // don't know what it does.
123
124 nsCOMPtr<nsPIEditorTransaction> pTxn = do_QueryInterface(aTransaction);
125 NS_ENSURE_TRUE(pTxn, NS_OK); // it's foreign so just bail!
126
127 // XXX: hack, not safe! need nsIEditTransaction!
128 EditTransactionBase* editTransactionBase = (EditTransactionBase*)aTransaction;
129 // determine if this incoming txn is a placeholder txn
130 nsCOMPtr<nsIAbsorbingTransaction> absorbingTransaction =
131 do_QueryObject(editTransactionBase);
132
133 // We are absorbing all transactions if mAbsorb is lit.
134 if (mAbsorb) {
135 RefPtr<CompositionTransaction> otherTransaction =
136 do_QueryObject(aTransaction);
137 if (otherTransaction) {
138 // special handling for CompositionTransaction's: they need to merge with
139 // any previous CompositionTransaction in this placeholder, if possible.
140 if (!mCompositionTransaction) {
141 // this is the first IME txn in the placeholder
142 mCompositionTransaction = otherTransaction;
143 AppendChild(editTransactionBase);
144 } else {
145 bool didMerge;
146 mCompositionTransaction->Merge(otherTransaction, &didMerge);
147 if (!didMerge) {
148 // it wouldn't merge. Earlier IME txn is already committed and will
149 // not absorb further IME txns. So just stack this one after it
150 // and remember it as a candidate for further merges.
151 mCompositionTransaction = otherTransaction;
152 AppendChild(editTransactionBase);
153 }
154 }
155 } else if (!absorbingTransaction) {
156 // See bug 171243: just drop incoming placeholders on the floor.
157 // Their children will be swallowed by this preexisting one.
158 AppendChild(editTransactionBase);
159 }
160 *aDidMerge = true;
161 // RememberEndingSelection();
162 // efficiency hack: no need to remember selection here, as we haven't yet
163 // finished the initial batch and we know we will be told when the batch ends.
164 // we can remeber the selection then.
165 } else {
166 // merge typing or IME or deletion transactions if the selection matches
167 if ((mName.get() == nsGkAtoms::TypingTxnName ||
168 mName.get() == nsGkAtoms::IMETxnName ||
169 mName.get() == nsGkAtoms::DeleteTxnName) && !mCommitted) {
170 if (absorbingTransaction) {
171 nsCOMPtr<nsIAtom> atom;
172 absorbingTransaction->GetTxnName(getter_AddRefs(atom));
173 if (atom && atom == mName) {
174 // check if start selection of next placeholder matches
175 // end selection of this placeholder
176 bool isSame;
177 absorbingTransaction->StartSelectionEquals(&mEndSel, &isSame);
178 if (isSame) {
179 mAbsorb = true; // we need to start absorbing again
180 absorbingTransaction->ForwardEndBatchTo(this);
181 // AppendChild(editTransactionBase);
182 // see bug 171243: we don't need to merge placeholders
183 // into placeholders. We just reactivate merging in the pre-existing
184 // placeholder and drop the new one on the floor. The EndPlaceHolderBatch()
185 // call on the new placeholder will be forwarded to this older one.
186 RememberEndingSelection();
187 *aDidMerge = true;
188 }
189 }
190 }
191 }
192 }
193 return NS_OK;
194 }
195
196 NS_IMETHODIMP
GetTxnDescription(nsAString & aString)197 PlaceholderTransaction::GetTxnDescription(nsAString& aString)
198 {
199 aString.AssignLiteral("PlaceholderTransaction: ");
200
201 if (mName) {
202 nsAutoString name;
203 mName->ToString(name);
204 aString += name;
205 }
206
207 return NS_OK;
208 }
209
210 NS_IMETHODIMP
GetTxnName(nsIAtom ** aName)211 PlaceholderTransaction::GetTxnName(nsIAtom** aName)
212 {
213 return GetName(aName);
214 }
215
216 NS_IMETHODIMP
StartSelectionEquals(SelectionState * aSelState,bool * aResult)217 PlaceholderTransaction::StartSelectionEquals(SelectionState* aSelState,
218 bool* aResult)
219 {
220 // determine if starting selection matches the given selection state.
221 // note that we only care about collapsed selections.
222 NS_ENSURE_TRUE(aResult && aSelState, NS_ERROR_NULL_POINTER);
223 if (!mStartSel->IsCollapsed() || !aSelState->IsCollapsed()) {
224 *aResult = false;
225 return NS_OK;
226 }
227 *aResult = mStartSel->IsEqual(aSelState);
228 return NS_OK;
229 }
230
231 NS_IMETHODIMP
EndPlaceHolderBatch()232 PlaceholderTransaction::EndPlaceHolderBatch()
233 {
234 mAbsorb = false;
235
236 if (mForwarding) {
237 nsCOMPtr<nsIAbsorbingTransaction> plcTxn = do_QueryReferent(mForwarding);
238 if (plcTxn) {
239 plcTxn->EndPlaceHolderBatch();
240 }
241 }
242 // remember our selection state.
243 return RememberEndingSelection();
244 }
245
246 NS_IMETHODIMP
ForwardEndBatchTo(nsIAbsorbingTransaction * aForwardingAddress)247 PlaceholderTransaction::ForwardEndBatchTo(
248 nsIAbsorbingTransaction* aForwardingAddress)
249 {
250 mForwarding = do_GetWeakReference(aForwardingAddress);
251 return NS_OK;
252 }
253
254 NS_IMETHODIMP
Commit()255 PlaceholderTransaction::Commit()
256 {
257 mCommitted = true;
258 return NS_OK;
259 }
260
261 nsresult
RememberEndingSelection()262 PlaceholderTransaction::RememberEndingSelection()
263 {
264 RefPtr<Selection> selection = mEditorBase->GetSelection();
265 NS_ENSURE_TRUE(selection, NS_ERROR_NULL_POINTER);
266 mEndSel.SaveSelection(selection);
267 return NS_OK;
268 }
269
270 } // namespace mozilla
271