summaryrefslogtreecommitdiffstats
path: root/layout/generic/nsSubDocumentFrame.cpp
blob: 731d31a16f165b980e4e16afaf35df82be9ad142 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

/*
 * rendering object for replaced elements that contain a document, such
 * as <frame>, <iframe>, and some <object>s
 */

#include "nsSubDocumentFrame.h"

#include "mozilla/ComputedStyleInlines.h"
#include "mozilla/Preferences.h"
#include "mozilla/PresShell.h"
#include "mozilla/StaticPrefs_layout.h"
#include "mozilla/Unused.h"
#include "mozilla/dom/Document.h"
#include "mozilla/dom/HTMLFrameElement.h"
#include "mozilla/dom/ImageDocument.h"
#include "mozilla/dom/BrowserParent.h"

#include "nsCOMPtr.h"
#include "nsGenericHTMLElement.h"
#include "nsGenericHTMLFrameElement.h"
#include "nsAttrValueInlines.h"
#include "nsIDocShell.h"
#include "nsIDocumentViewer.h"
#include "nsIContentInlines.h"
#include "nsPresContext.h"
#include "nsView.h"
#include "nsViewManager.h"
#include "nsGkAtoms.h"
#include "nsStyleConsts.h"
#include "nsStyleStruct.h"
#include "nsStyleStructInlines.h"
#include "nsFrameSetFrame.h"
#include "nsNameSpaceManager.h"
#include "nsDisplayList.h"
#include "nsIScrollableFrame.h"
#include "nsIObjectLoadingContent.h"
#include "nsLayoutUtils.h"
#include "nsContentUtils.h"
#include "nsServiceManagerUtils.h"
#include "nsQueryObject.h"
#include "RetainedDisplayListBuilder.h"
#include "nsObjectLoadingContent.h"

#include "mozilla/layers/WebRenderUserData.h"
#include "mozilla/layers/WebRenderScrollData.h"
#include "mozilla/layers/RenderRootStateManager.h"
#include "mozilla/layers/StackingContextHelper.h"  // for StackingContextHelper
#include "mozilla/ProfilerLabels.h"

using namespace mozilla;
using namespace mozilla::dom;
using namespace mozilla::gfx;
using namespace mozilla::layers;

static Document* GetDocumentFromView(nsView* aView) {
  MOZ_ASSERT(aView, "null view");

  nsViewManager* vm = aView->GetViewManager();
  PresShell* presShell = vm ? vm->GetPresShell() : nullptr;
  return presShell ? presShell->GetDocument() : nullptr;
}

static void PropagateIsUnderHiddenEmbedderElement(nsFrameLoader* aFrameLoader,
                                                  bool aValue) {
  if (!aFrameLoader) {
    return;
  }

  if (BrowsingContext* bc = aFrameLoader->GetExtantBrowsingContext()) {
    if (bc->IsUnderHiddenEmbedderElement() != aValue) {
      Unused << bc->SetIsUnderHiddenEmbedderElement(aValue);
    }
  }
}

nsSubDocumentFrame::nsSubDocumentFrame(ComputedStyle* aStyle,
                                       nsPresContext* aPresContext)
    : nsAtomicContainerFrame(aStyle, aPresContext, kClassID),
      mOuterView(nullptr),
      mInnerView(nullptr),
      mIsInline(false),
      mPostedReflowCallback(false),
      mDidCreateDoc(false),
      mCallingShow(false),
      mIsInObjectOrEmbed(false) {}

#ifdef ACCESSIBILITY
a11y::AccType nsSubDocumentFrame::AccessibleType() {
  return a11y::eOuterDocType;
}
#endif

NS_QUERYFRAME_HEAD(nsSubDocumentFrame)
  NS_QUERYFRAME_ENTRY(nsSubDocumentFrame)
NS_QUERYFRAME_TAIL_INHERITING(nsAtomicContainerFrame)

class AsyncFrameInit : public Runnable {
 public:
  explicit AsyncFrameInit(nsIFrame* aFrame)
      : mozilla::Runnable("AsyncFrameInit"), mFrame(aFrame) {}
  NS_IMETHOD Run() override {
    AUTO_PROFILER_LABEL("AsyncFrameInit::Run", OTHER);
    if (mFrame.IsAlive()) {
      static_cast<nsSubDocumentFrame*>(mFrame.GetFrame())->ShowViewer();
    }
    return NS_OK;
  }

 private:
  WeakFrame mFrame;
};

void nsSubDocumentFrame::Init(nsIContent* aContent, nsContainerFrame* aParent,
                              nsIFrame* aPrevInFlow) {
  MOZ_ASSERT(aContent);
  // determine if we are a <frame> or <iframe>
  mIsInline = !aContent->IsHTMLElement(nsGkAtoms::frame);

  nsAtomicContainerFrame::Init(aContent, aParent, aPrevInFlow);

  // CreateView() creates this frame's view, stored in mOuterView.  It needs to
  // be created first since it's the parent of the inner view, stored in
  // mInnerView.
  CreateView();
  EnsureInnerView();

  // Set the primary frame now so that nsDocumentViewer::FindContainerView
  // called from within EndSwapDocShellsForViews below can find it if needed.
  aContent->SetPrimaryFrame(this);

  // If we have a detached subdoc's root view on our frame loader, re-insert it
  // into the view tree. This happens when we've been reframed, and ensures the
  // presentation persists across reframes.
  if (RefPtr<nsFrameLoader> frameloader = FrameLoader()) {
    bool hadFrame = false;
    nsIFrame* detachedFrame = frameloader->GetDetachedSubdocFrame(&hadFrame);
    frameloader->SetDetachedSubdocFrame(nullptr);
    nsView* detachedView = detachedFrame ? detachedFrame->GetView() : nullptr;
    if (detachedView) {
      // Restore stashed presentation.
      InsertViewsInReverseOrder(detachedView, mInnerView);
      EndSwapDocShellsForViews(mInnerView->GetFirstChild());
    } else if (hadFrame) {
      // Presentation is for a different document, don't restore it.
      frameloader->Hide();
    }
  }

  // NOTE: The frame loader might not yet be initialized yet. If it's not, the
  // call in ShowViewer() should pick things up.
  UpdateEmbeddedBrowsingContextDependentData();
  nsContentUtils::AddScriptRunner(new AsyncFrameInit(this));
}

void nsSubDocumentFrame::UpdateEmbeddedBrowsingContextDependentData() {
  if (!mFrameLoader) {
    return;
  }
  BrowsingContext* bc = mFrameLoader->GetExtantBrowsingContext();
  if (!bc) {
    return;
  }
  mIsInObjectOrEmbed = bc->IsEmbedderTypeObjectOrEmbed();
  MaybeUpdateRemoteStyle();
  MaybeUpdateEmbedderColorScheme();
  PropagateIsUnderHiddenEmbedderElement(
      PresShell()->IsUnderHiddenEmbedderElement() ||
      !StyleVisibility()->IsVisible());
}

void nsSubDocumentFrame::PropagateIsUnderHiddenEmbedderElement(bool aValue) {
  ::PropagateIsUnderHiddenEmbedderElement(mFrameLoader, aValue);
}

void nsSubDocumentFrame::ShowViewer() {
  if (mCallingShow) {
    return;
  }

  RefPtr<nsFrameLoader> frameloader = FrameLoader();
  if (!frameloader || frameloader->IsDead()) {
    return;
  }

  if (!frameloader->IsRemoteFrame() && !PresContext()->IsDynamic()) {
    // We let the printing code take care of loading the document and
    // initializing the shell; just create the inner view for it to use.
    (void)EnsureInnerView();
  } else {
    AutoWeakFrame weakThis(this);
    mCallingShow = true;
    bool didCreateDoc = frameloader->Show(this);
    if (!weakThis.IsAlive()) {
      return;
    }
    mCallingShow = false;
    mDidCreateDoc = didCreateDoc;
    if (!HasAnyStateBits(NS_FRAME_FIRST_REFLOW)) {
      frameloader->UpdatePositionAndSize(this);
    }
    if (!weakThis.IsAlive()) {
      return;
    }
    UpdateEmbeddedBrowsingContextDependentData();
    InvalidateFrame();
  }
}

nsIFrame* nsSubDocumentFrame::GetSubdocumentRootFrame() {
  if (!mInnerView) return nullptr;
  nsView* subdocView = mInnerView->GetFirstChild();
  return subdocView ? subdocView->GetFrame() : nullptr;
}

mozilla::PresShell* nsSubDocumentFrame::GetSubdocumentPresShellForPainting(
    uint32_t aFlags) {
  if (!mInnerView) return nullptr;

  nsView* subdocView = mInnerView->GetFirstChild();
  if (!subdocView) return nullptr;

  mozilla::PresShell* presShell = nullptr;

  nsIFrame* subdocRootFrame = subdocView->GetFrame();
  if (subdocRootFrame) {
    presShell = subdocRootFrame->PresShell();
  }

  // If painting is suppressed in the presshell, we try to look for a better
  // presshell to use.
  if (!presShell || (presShell->IsPaintingSuppressed() &&
                     !(aFlags & IGNORE_PAINT_SUPPRESSION))) {
    // During page transition mInnerView will sometimes have two children, the
    // first being the new page that may not have any frame, and the second
    // being the old page that will probably have a frame.
    nsView* nextView = subdocView->GetNextSibling();
    nsIFrame* frame = nullptr;
    if (nextView) {
      frame = nextView->GetFrame();
    }
    if (frame) {
      mozilla::PresShell* presShellForNextView = frame->PresShell();
      if (!presShell || (presShellForNextView &&
                         !presShellForNextView->IsPaintingSuppressed() &&
                         StaticPrefs::layout_show_previous_page())) {
        subdocView = nextView;
        subdocRootFrame = frame;
        presShell = presShellForNextView;
      }
    }
    if (!presShell) {
      // If we don't have a frame we use this roundabout way to get the pres
      // shell.
      if (!mFrameLoader) return nullptr;
      nsIDocShell* docShell = mFrameLoader->GetDocShell(IgnoreErrors());
      if (!docShell) return nullptr;
      presShell = docShell->GetPresShell();
    }
  }

  return presShell;
}

nsRect nsSubDocumentFrame::GetDestRect() {
  nsRect rect = GetContent()->IsHTMLElement(nsGkAtoms::frame)
                    ? GetRectRelativeToSelf()
                    : GetContentRectRelativeToSelf();

  // Adjust subdocument size, according to 'object-fit' and the subdocument's
  // intrinsic size and ratio.
  return nsLayoutUtils::ComputeObjectDestRect(
      rect, GetIntrinsicSize(), GetIntrinsicRatio(), StylePosition());
}

ScreenIntSize nsSubDocumentFrame::GetSubdocumentSize() {
  if (HasAnyStateBits(NS_FRAME_FIRST_REFLOW)) {
    if (RefPtr<nsFrameLoader> frameloader = FrameLoader()) {
      nsIFrame* detachedFrame = frameloader->GetDetachedSubdocFrame();
      if (nsView* view = detachedFrame ? detachedFrame->GetView() : nullptr) {
        nsSize size = view->GetBounds().Size();
        nsPresContext* presContext = detachedFrame->PresContext();
        return ScreenIntSize(presContext->AppUnitsToDevPixels(size.width),
                             presContext->AppUnitsToDevPixels(size.height));
      }
    }
    // Pick some default size for now.  Using 10x10 because that's what the
    // code used to do.
    return ScreenIntSize(10, 10);
  }

  nsSize docSizeAppUnits = GetDestRect().Size();
  nsPresContext* pc = PresContext();
  return ScreenIntSize(pc->AppUnitsToDevPixels(docSizeAppUnits.width),
                       pc->AppUnitsToDevPixels(docSizeAppUnits.height));
}

static void WrapBackgroundColorInOwnLayer(nsDisplayListBuilder* aBuilder,
                                          nsIFrame* aFrame,
                                          nsDisplayList* aList) {
  for (nsDisplayItem* item : aList->TakeItems()) {
    if (item->GetType() == DisplayItemType::TYPE_BACKGROUND_COLOR) {
      nsDisplayList tmpList(aBuilder);
      tmpList.AppendToTop(item);
      item = MakeDisplayItemWithIndex<nsDisplayOwnLayer>(
          aBuilder, aFrame, /* aIndex = */ nsDisplayOwnLayer::OwnLayerForSubdoc,
          &tmpList, aBuilder->CurrentActiveScrolledRoot(),
          nsDisplayOwnLayerFlags::None, ScrollbarData{}, true, false);
    }
    aList->AppendToTop(item);
  }
}

void nsSubDocumentFrame::BuildDisplayList(nsDisplayListBuilder* aBuilder,
                                          const nsDisplayListSet& aLists) {
  if (!IsVisibleForPainting()) {
    return;
  }

  const bool pointerEventsNone =
      Style()->PointerEvents() == StylePointerEvents::None;
  if (aBuilder->IsForEventDelivery() && pointerEventsNone) {
    // If we are pointer-events:none then we don't need to HitTest background or
    // anything else.
    return;
  }

  nsFrameLoader* frameLoader = FrameLoader();
  const bool isRemoteFrame = frameLoader && frameLoader->IsRemoteFrame();

  nsDisplayListCollection decorations(aBuilder);
  DisplayBorderBackgroundOutline(aBuilder, decorations);
  if (isRemoteFrame) {
    // Wrap background colors of <iframe>s with remote subdocuments in their
    // own layer so we generate a ColorLayer. This is helpful for optimizing
    // compositing; we can skip compositing the ColorLayer when the
    // remote content is opaque.
    WrapBackgroundColorInOwnLayer(aBuilder, this,
                                  decorations.BorderBackground());
  }
  decorations.MoveTo(aLists);

  if (HidesContent()) {
    return;
  }

  // If we're passing pointer events to children then we have to descend into
  // subdocuments no matter what, to determine which parts are transparent for
  // hit-testing or event regions.
  bool needToDescend = aBuilder->GetDescendIntoSubdocuments();
  if (!mInnerView || !needToDescend) {
    return;
  }

  if (isRemoteFrame) {
    // We're the subdoc for <browser remote="true"> and it has
    // painted content.  Display its shadow layer tree.
    DisplayListClipState::AutoSaveRestore clipState(aBuilder);
    clipState.ClipContainingBlockDescendantsToContentBox(aBuilder, this);

    aLists.Content()->AppendNewToTop<nsDisplayRemote>(aBuilder, this);
    return;
  }

  RefPtr<mozilla::PresShell> presShell = GetSubdocumentPresShellForPainting(
      aBuilder->IsIgnoringPaintSuppression() ? IGNORE_PAINT_SUPPRESSION : 0);

  if (!presShell) {
    return;
  }

  if (aBuilder->IsInFilter()) {
    Document* outerDoc = PresShell()->GetDocument();
    Document* innerDoc = presShell->GetDocument();
    if (outerDoc && innerDoc) {
      if (!outerDoc->NodePrincipal()->Equals(innerDoc->NodePrincipal())) {
        outerDoc->SetUseCounter(eUseCounter_custom_FilteredCrossOriginIFrame);
      }
    }
  }

  nsIFrame* subdocRootFrame = presShell->GetRootFrame();

  nsPresContext* presContext = presShell->GetPresContext();

  int32_t parentAPD = PresContext()->AppUnitsPerDevPixel();
  int32_t subdocAPD = presContext->AppUnitsPerDevPixel();

  nsRect visible;
  nsRect dirty;
  bool ignoreViewportScrolling = false;
  if (subdocRootFrame) {
    // get the dirty rect relative to the root frame of the subdoc
    visible = aBuilder->GetVisibleRect() + GetOffsetToCrossDoc(subdocRootFrame);
    dirty = aBuilder->GetDirtyRect() + GetOffsetToCrossDoc(subdocRootFrame);
    // and convert into the appunits of the subdoc
    visible = visible.ScaleToOtherAppUnitsRoundOut(parentAPD, subdocAPD);
    dirty = dirty.ScaleToOtherAppUnitsRoundOut(parentAPD, subdocAPD);

    if (nsIScrollableFrame* rootScrollableFrame =
            presShell->GetRootScrollFrameAsScrollable()) {
      // Use a copy, so the rects don't get modified.
      nsRect copyOfDirty = dirty;
      nsRect copyOfVisible = visible;
      // TODO(botond): Can we just axe this DecideScrollableLayer call?
      rootScrollableFrame->DecideScrollableLayer(aBuilder, &copyOfVisible,
                                                 &copyOfDirty,
                                                 /* aSetBase = */ true);

      ignoreViewportScrolling = presShell->IgnoringViewportScrolling();
    }

    aBuilder->EnterPresShell(subdocRootFrame, pointerEventsNone);
    aBuilder->IncrementPresShellPaintCount(presShell);
  } else {
    visible = aBuilder->GetVisibleRect();
    dirty = aBuilder->GetDirtyRect();
  }

  DisplayListClipState::AutoSaveRestore clipState(aBuilder);
  clipState.ClipContainingBlockDescendantsToContentBox(aBuilder, this);

  nsIScrollableFrame* sf = presShell->GetRootScrollFrameAsScrollable();
  bool constructZoomItem = subdocRootFrame && parentAPD != subdocAPD;
  bool needsOwnLayer = constructZoomItem ||
                       presContext->IsRootContentDocumentCrossProcess() ||
                       (sf && sf->IsScrollingActive());

  nsDisplayList childItems(aBuilder);

  {
    DisplayListClipState::AutoSaveRestore nestedClipState(aBuilder);
    if (needsOwnLayer) {
      // Clear current clip. There's no point in propagating it down, since
      // the layer we will construct will be clipped by the current clip.
      // In fact for nsDisplayZoom propagating it down would be incorrect since
      // nsDisplayZoom changes the meaning of appunits.
      nestedClipState.Clear();
    }

    // Invoke AutoBuildingDisplayList to ensure that the correct dirty rect
    // is used to compute the visible rect if AddCanvasBackgroundColorItem
    // creates a display item.
    nsIFrame* frame = subdocRootFrame ? subdocRootFrame : this;
    nsDisplayListBuilder::AutoBuildingDisplayList building(aBuilder, frame,
                                                           visible, dirty);

    if (subdocRootFrame) {
      bool hasDocumentLevelListenersForApzAwareEvents =
          gfxPlatform::AsyncPanZoomEnabled() &&
          nsLayoutUtils::HasDocumentLevelListenersForApzAwareEvents(presShell);

      aBuilder->SetAncestorHasApzAwareEventHandler(
          hasDocumentLevelListenersForApzAwareEvents);
      subdocRootFrame->BuildDisplayListForStackingContext(aBuilder,
                                                          &childItems);
      if (!aBuilder->IsForEventDelivery()) {
        // If we are going to use a displayzoom below then any items we put
        // under it need to have underlying frames from the subdocument. So we
        // need to calculate the bounds based on which frame will be the
        // underlying frame for the canvas background color item.
        nsRect bounds =
            GetContentRectRelativeToSelf() + aBuilder->ToReferenceFrame(this);
        bounds = bounds.ScaleToOtherAppUnitsRoundOut(parentAPD, subdocAPD);

        // Add the canvas background color to the bottom of the list. This
        // happens after we've built the list so that
        // AddCanvasBackgroundColorItem can monkey with the contents if
        // necessary.
        presShell->AddCanvasBackgroundColorItem(aBuilder, &childItems, frame,
                                                bounds, NS_RGBA(0, 0, 0, 0));
      }
    }
  }

  if (subdocRootFrame) {
    aBuilder->LeavePresShell(subdocRootFrame, &childItems);
  }

  // Generate a resolution and/or zoom item if needed. If one or both of those
  // is created, we don't need to create a separate nsDisplaySubDocument.

  nsDisplayOwnLayerFlags flags =
      nsDisplayOwnLayerFlags::GenerateSubdocInvalidations;
  // If ignoreViewportScrolling is true then the top most layer we create here
  // is going to become the scrollable layer for the root scroll frame, so we
  // want to add nsDisplayOwnLayer::GENERATE_SCROLLABLE_LAYER to whatever layer
  // becomes the topmost. We do this below.
  if (constructZoomItem) {
    nsDisplayOwnLayerFlags zoomFlags = flags;
    if (ignoreViewportScrolling) {
      zoomFlags |= nsDisplayOwnLayerFlags::GenerateScrollableLayer;
    }
    childItems.AppendNewToTop<nsDisplayZoom>(aBuilder, subdocRootFrame, this,
                                             &childItems, subdocAPD, parentAPD,
                                             zoomFlags);

    needsOwnLayer = false;
  }
  // Wrap the zoom item in the resolution item if we have both because we want
  // the resolution scale applied on top of the app units per dev pixel
  // conversion.
  if (ignoreViewportScrolling) {
    flags |= nsDisplayOwnLayerFlags::GenerateScrollableLayer;
  }

  // We always want top level content documents to be in their own layer.
  nsDisplaySubDocument* layerItem = MakeDisplayItem<nsDisplaySubDocument>(
      aBuilder, subdocRootFrame ? subdocRootFrame : this, this, &childItems,
      flags);
  if (layerItem) {
    childItems.AppendToTop(layerItem);
    layerItem->SetShouldFlattenAway(!needsOwnLayer);
  }

  if (aBuilder->IsForFrameVisibility()) {
    // We don't add the childItems to the return list as we're dealing with them
    // here.
    presShell->RebuildApproximateFrameVisibilityDisplayList(childItems);
    childItems.DeleteAll(aBuilder);
  } else {
    aLists.Content()->AppendToTop(&childItems);
  }
}

#ifdef DEBUG_FRAME_DUMP
void nsSubDocumentFrame::List(FILE* out, const char* aPrefix,
                              ListFlags aFlags) const {
  nsCString str;
  ListGeneric(str, aPrefix, aFlags);
  fprintf_stderr(out, "%s\n", str.get());

  if (aFlags.contains(ListFlag::TraverseSubdocumentFrames)) {
    nsSubDocumentFrame* f = const_cast<nsSubDocumentFrame*>(this);
    nsIFrame* subdocRootFrame = f->GetSubdocumentRootFrame();
    if (subdocRootFrame) {
      nsCString pfx(aPrefix);
      pfx += "  ";
      subdocRootFrame->List(out, pfx.get(), aFlags);
    }
  }
}

nsresult nsSubDocumentFrame::GetFrameName(nsAString& aResult) const {
  return MakeFrameName(u"FrameOuter"_ns, aResult);
}
#endif

/* virtual */
nscoord nsSubDocumentFrame::GetMinISize(gfxContext* aRenderingContext) {
  return GetIntrinsicISize();
}

/* virtual */
nscoord nsSubDocumentFrame::GetPrefISize(gfxContext* aRenderingContext) {
  // If the subdocument is an SVG document, then in theory we want to return
  // the same thing that SVGOuterSVGFrame::GetPrefISize does.  That method
  // has some special handling of percentage values to avoid unhelpful zero
  // sizing in the presence of orthogonal writing modes.  We don't bother
  // with that for SVG documents in <embed> and <object>, since that special
  // handling doesn't look up across document boundaries anyway.
  return GetIntrinsicISize();
}

/* virtual */
IntrinsicSize nsSubDocumentFrame::GetIntrinsicSize() {
  const auto containAxes = GetContainSizeAxes();
  if (containAxes.IsBoth()) {
    // Intrinsic size of 'contain:size' replaced elements is determined by
    // contain-intrinsic-size.
    return FinishIntrinsicSize(containAxes, IntrinsicSize(0, 0));
  }

  if (nsCOMPtr<nsIObjectLoadingContent> iolc = do_QueryInterface(mContent)) {
    const auto* olc = static_cast<nsObjectLoadingContent*>(iolc.get());
    if (auto size = olc->GetSubdocumentIntrinsicSize()) {
      // Use the intrinsic size from the child SVG document, if available.
      return FinishIntrinsicSize(containAxes, *size);
    }
  }

  if (!IsInline()) {
    return {};  // <frame> elements have no useful intrinsic size.
  }

  if (mContent->IsXULElement()) {
    return {};  // XUL <iframe> and <browser> have no useful intrinsic size
  }

  // We must be an HTML <iframe>. Return fallback size.
  return FinishIntrinsicSize(containAxes,
                             IntrinsicSize(kFallbackIntrinsicSize));
}

/* virtual */
AspectRatio nsSubDocumentFrame::GetIntrinsicRatio() const {
  // FIXME(emilio): This should probably respect contain: size and return no
  // ratio in the case subDocRoot is non-null. Otherwise we do it by virtue of
  // using a zero-size below and reusing GetIntrinsicSize().
  if (nsCOMPtr<nsIObjectLoadingContent> iolc = do_QueryInterface(mContent)) {
    auto olc = static_cast<nsObjectLoadingContent*>(iolc.get());

    auto ratio = olc->GetSubdocumentIntrinsicRatio();
    if (ratio && *ratio) {
      // Use the intrinsic aspect ratio from the child SVG document, if
      // available.
      return *ratio;
    }
  }

  // NOTE(emilio): Even though we have an intrinsic size, we may not have an
  // intrinsic ratio. For example `<iframe style="width: 100px">` should not
  // shrink in the vertical axis to preserve the 300x150 ratio.
  return nsAtomicContainerFrame::GetIntrinsicRatio();
}

/* virtual */
LogicalSize nsSubDocumentFrame::ComputeAutoSize(
    gfxContext* aRenderingContext, WritingMode aWM, const LogicalSize& aCBSize,
    nscoord aAvailableISize, const LogicalSize& aMargin,
    const LogicalSize& aBorderPadding, const StyleSizeOverrides& aSizeOverrides,
    ComputeSizeFlags aFlags) {
  if (!IsInline()) {
    return nsIFrame::ComputeAutoSize(aRenderingContext, aWM, aCBSize,
                                     aAvailableISize, aMargin, aBorderPadding,
                                     aSizeOverrides, aFlags);
  }

  const WritingMode wm = GetWritingMode();
  LogicalSize result(wm, GetIntrinsicISize(), GetIntrinsicBSize());
  return result.ConvertTo(aWM, wm);
}

/* virtual */
nsIFrame::SizeComputationResult nsSubDocumentFrame::ComputeSize(
    gfxContext* aRenderingContext, WritingMode aWM, const LogicalSize& aCBSize,
    nscoord aAvailableISize, const LogicalSize& aMargin,
    const LogicalSize& aBorderPadding, const StyleSizeOverrides& aSizeOverrides,
    ComputeSizeFlags aFlags) {
  return {ComputeSizeWithIntrinsicDimensions(
              aRenderingContext, aWM, GetIntrinsicSize(), GetAspectRatio(),
              aCBSize, aMargin, aBorderPadding, aSizeOverrides, aFlags),
          AspectRatioUsage::None};
}

void nsSubDocumentFrame::Reflow(nsPresContext* aPresContext,
                                ReflowOutput& aDesiredSize,
                                const ReflowInput& aReflowInput,
                                nsReflowStatus& aStatus) {
  MarkInReflow();
  DO_GLOBAL_REFLOW_COUNT("nsSubDocumentFrame");
  MOZ_ASSERT(aStatus.IsEmpty(), "Caller should pass a fresh reflow status!");
  NS_FRAME_TRACE(
      NS_FRAME_TRACE_CALLS,
      ("enter nsSubDocumentFrame::Reflow: maxSize=%d,%d",
       aReflowInput.AvailableWidth(), aReflowInput.AvailableHeight()));

  NS_ASSERTION(aReflowInput.ComputedISize() != NS_UNCONSTRAINEDSIZE,
               "Shouldn't have unconstrained inline-size here "
               "thanks to the rules of reflow");
  NS_ASSERTION(aReflowInput.ComputedBSize() != NS_UNCONSTRAINEDSIZE,
               "Shouldn't have unconstrained block-size here "
               "thanks to ComputeAutoSize");

  NS_ASSERTION(mContent->GetPrimaryFrame() == this, "Shouldn't happen");

  // XUL <iframe> or <browser>, or HTML <iframe>, <object> or <embed>
  const auto wm = aReflowInput.GetWritingMode();
  aDesiredSize.SetSize(wm, aReflowInput.ComputedSizeWithBorderPadding(wm));

  // "offset" is the offset of our content area from our frame's
  // top-left corner.
  nsPoint offset = nsPoint(aReflowInput.ComputedPhysicalBorderPadding().left,
                           aReflowInput.ComputedPhysicalBorderPadding().top);

  if (mInnerView) {
    const nsMargin& bp = aReflowInput.ComputedPhysicalBorderPadding();
    nsSize innerSize(aDesiredSize.Width() - bp.LeftRight(),
                     aDesiredSize.Height() - bp.TopBottom());

    // Size & position the view according to 'object-fit' & 'object-position'.
    nsRect destRect = nsLayoutUtils::ComputeObjectDestRect(
        nsRect(offset, innerSize), GetIntrinsicSize(), GetIntrinsicRatio(),
        StylePosition());

    nsViewManager* vm = mInnerView->GetViewManager();
    vm->MoveViewTo(mInnerView, destRect.x, destRect.y);
    vm->ResizeView(mInnerView, nsRect(nsPoint(0, 0), destRect.Size()));
  }

  aDesiredSize.SetOverflowAreasToDesiredBounds();

  FinishAndStoreOverflow(&aDesiredSize);

  if (!aPresContext->IsRootPaginatedDocument() && !mPostedReflowCallback) {
    PresShell()->PostReflowCallback(this);
    mPostedReflowCallback = true;
  }

  NS_FRAME_TRACE(
      NS_FRAME_TRACE_CALLS,
      ("exit nsSubDocumentFrame::Reflow: size=%d,%d status=%s",
       aDesiredSize.Width(), aDesiredSize.Height(), ToString(aStatus).c_str()));
}

bool nsSubDocumentFrame::ReflowFinished() {
  RefPtr<nsFrameLoader> frameloader = FrameLoader();
  if (frameloader) {
    AutoWeakFrame weakFrame(this);

    frameloader->UpdatePositionAndSize(this);

    if (weakFrame.IsAlive()) {
      // Make sure that we can post a reflow callback in the future.
      mPostedReflowCallback = false;
    }
  } else {
    mPostedReflowCallback = false;
  }
  return false;
}

void nsSubDocumentFrame::ReflowCallbackCanceled() {
  mPostedReflowCallback = false;
}

nsresult nsSubDocumentFrame::AttributeChanged(int32_t aNameSpaceID,
                                              nsAtom* aAttribute,
                                              int32_t aModType) {
  if (aNameSpaceID != kNameSpaceID_None) {
    return NS_OK;
  }

  // If the noResize attribute changes, dis/allow frame to be resized
  if (aAttribute == nsGkAtoms::noresize) {
    // Note that we're not doing content type checks, but that's ok -- if
    // they'd fail we will just end up with a null framesetFrame.
    if (mContent->GetParent()->IsHTMLElement(nsGkAtoms::frameset)) {
      nsIFrame* parentFrame = GetParent();

      if (parentFrame) {
        // There is no interface for nsHTMLFramesetFrame so QI'ing to
        // concrete class, yay!
        nsHTMLFramesetFrame* framesetFrame = do_QueryFrame(parentFrame);
        if (framesetFrame) {
          framesetFrame->RecalculateBorderResize();
        }
      }
    }
  } else if (aAttribute == nsGkAtoms::marginwidth ||
             aAttribute == nsGkAtoms::marginheight) {
    // Notify the frameloader
    if (RefPtr<nsFrameLoader> frameloader = FrameLoader()) {
      frameloader->MarginsChanged();
    }
  }

  return NS_OK;
}

void nsSubDocumentFrame::MaybeUpdateEmbedderColorScheme() {
  nsFrameLoader* fl = mFrameLoader.get();
  if (!fl) {
    return;
  }

  BrowsingContext* bc = fl->GetExtantBrowsingContext();
  if (!bc) {
    return;
  }

  auto ToOverride = [](ColorScheme aScheme) -> PrefersColorSchemeOverride {
    return aScheme == ColorScheme::Dark ? PrefersColorSchemeOverride::Dark
                                        : PrefersColorSchemeOverride::Light;
  };

  EmbedderColorSchemes schemes{
      ToOverride(LookAndFeel::ColorSchemeForFrame(this, ColorSchemeMode::Used)),
      ToOverride(
          LookAndFeel::ColorSchemeForFrame(this, ColorSchemeMode::Preferred))};
  if (bc->GetEmbedderColorSchemes() == schemes) {
    return;
  }

  Unused << bc->SetEmbedderColorSchemes(schemes);
}

void nsSubDocumentFrame::MaybeUpdateRemoteStyle(
    ComputedStyle* aOldComputedStyle) {
  if (!mIsInObjectOrEmbed) {
    return;
  }

  if (aOldComputedStyle &&
      aOldComputedStyle->StyleVisibility()->mImageRendering ==
          Style()->StyleVisibility()->mImageRendering) {
    return;
  }

  if (!mFrameLoader) {
    return;
  }

  if (mFrameLoader->IsRemoteFrame()) {
    mFrameLoader->UpdateRemoteStyle(
        Style()->StyleVisibility()->mImageRendering);
    return;
  }

  BrowsingContext* context = mFrameLoader->GetExtantBrowsingContext();
  if (!context) {
    return;
  }

  Document* document = context->GetDocument();
  if (!document) {
    return;
  }

  if (document->IsImageDocument()) {
    document->AsImageDocument()->UpdateRemoteStyle(
        Style()->StyleVisibility()->mImageRendering);
  }
}

void nsSubDocumentFrame::DidSetComputedStyle(ComputedStyle* aOldComputedStyle) {
  nsAtomicContainerFrame::DidSetComputedStyle(aOldComputedStyle);

  MaybeUpdateEmbedderColorScheme();

  MaybeUpdateRemoteStyle(aOldComputedStyle);

  // If this presshell has invisible ancestors, we don't need to propagate the
  // visibility style change to the subdocument since the subdocument should
  // have already set the IsUnderHiddenEmbedderElement flag in
  // nsSubDocumentFrame::Init.
  if (PresShell()->IsUnderHiddenEmbedderElement()) {
    return;
  }

  const bool isVisible = StyleVisibility()->IsVisible();
  if (!aOldComputedStyle ||
      isVisible != aOldComputedStyle->StyleVisibility()->IsVisible()) {
    PropagateIsUnderHiddenEmbedderElement(!isVisible);
  }
}

nsIFrame* NS_NewSubDocumentFrame(PresShell* aPresShell, ComputedStyle* aStyle) {
  return new (aPresShell)
      nsSubDocumentFrame(aStyle, aPresShell->GetPresContext());
}

NS_IMPL_FRAMEARENA_HELPERS(nsSubDocumentFrame)

class nsHideViewer final : public Runnable {
 public:
  nsHideViewer(nsIContent* aFrameElement, nsFrameLoader* aFrameLoader,
               PresShell* aPresShell, bool aHideViewerIfFrameless)
      : mozilla::Runnable("nsHideViewer"),
        mFrameElement(aFrameElement),
        mFrameLoader(aFrameLoader),
        mPresShell(aPresShell),
        mHideViewerIfFrameless(aHideViewerIfFrameless) {
    NS_ASSERTION(mFrameElement, "Must have a frame element");
    NS_ASSERTION(mFrameLoader, "Must have a frame loader");
    NS_ASSERTION(mPresShell, "Must have a presshell");
  }

  MOZ_CAN_RUN_SCRIPT_BOUNDARY NS_IMETHOD Run() override {
    // Flush frames, to ensure any pending display:none changes are made.
    // Note it can be unsafe to flush if we've destroyed the presentation
    // for some other reason, like if we're shutting down.
    //
    // But avoid the flush if we know for sure we're away, like when we're out
    // of the document already.
    //
    // FIXME(emilio): This could still be a perf footgun when removing lots of
    // siblings where each of them cause the reframe of an ancestor which happen
    // to contain a subdocument.
    //
    // We should find some way to avoid that!
    if (!mPresShell->IsDestroying() && mFrameElement->IsInComposedDoc()) {
      mPresShell->FlushPendingNotifications(FlushType::Frames);
    }

    // Either the frame has been constructed by now, or it never will be,
    // either way we want to clear the stashed views.
    mFrameLoader->SetDetachedSubdocFrame(nullptr);

    nsSubDocumentFrame* frame = do_QueryFrame(mFrameElement->GetPrimaryFrame());
    if (!frame || frame->FrameLoader() != mFrameLoader) {
      PropagateIsUnderHiddenEmbedderElement(mFrameLoader, true);
      if (mHideViewerIfFrameless) {
        // The frame element has no nsIFrame for the same frame loader.
        // Hide the nsFrameLoader, which destroys the presentation.
        mFrameLoader->Hide();
      }
    }
    return NS_OK;
  }

 private:
  const nsCOMPtr<nsIContent> mFrameElement;
  const RefPtr<nsFrameLoader> mFrameLoader;
  const RefPtr<PresShell> mPresShell;
  const bool mHideViewerIfFrameless;
};

static nsView* BeginSwapDocShellsForViews(nsView* aSibling);

void nsSubDocumentFrame::Destroy(DestroyContext& aContext) {
  if (mPostedReflowCallback) {
    PresShell()->CancelReflowCallback(this);
    mPostedReflowCallback = false;
  }

  // Detach the subdocument's views and stash them in the frame loader.
  // We can then reattach them if we're being reframed (for example if
  // the frame has been made position:fixed).
  if (RefPtr<nsFrameLoader> frameloader = FrameLoader()) {
    ClearDisplayItems();

    nsView* detachedViews =
        ::BeginSwapDocShellsForViews(mInnerView->GetFirstChild());

    frameloader->SetDetachedSubdocFrame(
        detachedViews ? detachedViews->GetFrame() : nullptr);

    // We call nsFrameLoader::HideViewer() in a script runner so that we can
    // safely determine whether the frame is being reframed or destroyed.
    nsContentUtils::AddScriptRunner(new nsHideViewer(
        mContent, frameloader, PresShell(), (mDidCreateDoc || mCallingShow)));
  }

  nsAtomicContainerFrame::Destroy(aContext);
}

nsFrameLoader* nsSubDocumentFrame::FrameLoader() const {
  if (mFrameLoader) {
    return mFrameLoader;
  }

  if (RefPtr<nsFrameLoaderOwner> loaderOwner = do_QueryObject(GetContent())) {
    mFrameLoader = loaderOwner->GetFrameLoader();
  }

  return mFrameLoader;
}

auto nsSubDocumentFrame::GetRemotePaintData() const -> RemoteFramePaintData {
  if (mRetainedRemoteFrame) {
    return *mRetainedRemoteFrame;
  }

  RemoteFramePaintData data;
  nsFrameLoader* fl = FrameLoader();
  if (!fl) {
    return data;
  }

  auto* rb = fl->GetRemoteBrowser();
  if (!rb) {
    return data;
  }
  data.mLayersId = rb->GetLayersId();
  data.mTabId = rb->GetTabId();
  return data;
}

void nsSubDocumentFrame::ResetFrameLoader(RetainPaintData aRetain) {
  if (aRetain == RetainPaintData::Yes && mFrameLoader) {
    mRetainedRemoteFrame = Some(GetRemotePaintData());
  } else {
    mRetainedRemoteFrame.reset();
  }
  mFrameLoader = nullptr;
  ClearDisplayItems();
  nsContentUtils::AddScriptRunner(new AsyncFrameInit(this));
}

void nsSubDocumentFrame::ClearRetainedPaintData() {
  mRetainedRemoteFrame.reset();
  ClearDisplayItems();
  InvalidateFrameSubtree();
}

// XXX this should be called ObtainDocShell or something like that,
// to indicate that it could have side effects
nsIDocShell* nsSubDocumentFrame::GetDocShell() const {
  // How can FrameLoader() return null???
  if (NS_WARN_IF(!FrameLoader())) {
    return nullptr;
  }
  return mFrameLoader->GetDocShell(IgnoreErrors());
}

static void DestroyDisplayItemDataForFrames(nsIFrame* aFrame) {
  // Destroying a WebRenderUserDataTable can cause destruction of other objects
  // which can remove frame properties in their destructor. If we delete a frame
  // property it runs the destructor of the stored object in the middle of
  // updating the frame property table, so if the destruction of that object
  // causes another update to the frame property table it would leave the frame
  // property table in an inconsistent state. So we remove it from the table and
  // then destroy it. (bug 1530657)
  WebRenderUserDataTable* userDataTable =
      aFrame->TakeProperty(WebRenderUserDataProperty::Key());
  if (userDataTable) {
    for (const auto& data : userDataTable->Values()) {
      data->RemoveFromTable();
    }
    delete userDataTable;
  }

  for (const auto& childList : aFrame->ChildLists()) {
    for (nsIFrame* child : childList.mList) {
      DestroyDisplayItemDataForFrames(child);
    }
  }
}

static CallState BeginSwapDocShellsForDocument(Document& aDocument) {
  if (PresShell* presShell = aDocument.GetPresShell()) {
    // Disable painting while the views are detached, see bug 946929.
    presShell->SetNeverPainting(true);

    if (nsIFrame* rootFrame = presShell->GetRootFrame()) {
      ::DestroyDisplayItemDataForFrames(rootFrame);
    }
  }
  aDocument.EnumerateSubDocuments(BeginSwapDocShellsForDocument);
  return CallState::Continue;
}

static nsView* BeginSwapDocShellsForViews(nsView* aSibling) {
  // Collect the removed sibling views in reverse order in 'removedViews'.
  nsView* removedViews = nullptr;
  while (aSibling) {
    if (Document* doc = ::GetDocumentFromView(aSibling)) {
      ::BeginSwapDocShellsForDocument(*doc);
    }
    nsView* next = aSibling->GetNextSibling();
    aSibling->GetViewManager()->RemoveChild(aSibling);
    aSibling->SetNextSibling(removedViews);
    removedViews = aSibling;
    aSibling = next;
  }
  return removedViews;
}

/* static */
void nsSubDocumentFrame::InsertViewsInReverseOrder(nsView* aSibling,
                                                   nsView* aParent) {
  MOZ_ASSERT(aParent, "null view");
  MOZ_ASSERT(!aParent->GetFirstChild(), "inserting into non-empty list");

  nsViewManager* vm = aParent->GetViewManager();
  while (aSibling) {
    nsView* next = aSibling->GetNextSibling();
    aSibling->SetNextSibling(nullptr);
    // true means 'after' in document order which is 'before' in view order,
    // so this call prepends the child, thus reversing the siblings as we go.
    vm->InsertChild(aParent, aSibling, nullptr, true);
    aSibling = next;
  }
}

nsresult nsSubDocumentFrame::BeginSwapDocShells(nsIFrame* aOther) {
  if (!aOther || !aOther->IsSubDocumentFrame()) {
    return NS_ERROR_NOT_IMPLEMENTED;
  }

  nsSubDocumentFrame* other = static_cast<nsSubDocumentFrame*>(aOther);
  if (!mFrameLoader || !mDidCreateDoc || mCallingShow || !other->mFrameLoader ||
      !other->mDidCreateDoc) {
    return NS_ERROR_NOT_IMPLEMENTED;
  }

  ClearDisplayItems();
  other->ClearDisplayItems();

  if (mInnerView && other->mInnerView) {
    nsView* ourSubdocViews = mInnerView->GetFirstChild();
    nsView* ourRemovedViews = ::BeginSwapDocShellsForViews(ourSubdocViews);
    nsView* otherSubdocViews = other->mInnerView->GetFirstChild();
    nsView* otherRemovedViews = ::BeginSwapDocShellsForViews(otherSubdocViews);

    InsertViewsInReverseOrder(ourRemovedViews, other->mInnerView);
    InsertViewsInReverseOrder(otherRemovedViews, mInnerView);
  }
  mFrameLoader.swap(other->mFrameLoader);
  return NS_OK;
}

static CallState EndSwapDocShellsForDocument(Document& aDocument) {
  // Our docshell and view trees have been updated for the new hierarchy.
  // Now also update all nsDeviceContext::mWidget to that of the
  // container view in the new hierarchy.
  if (nsCOMPtr<nsIDocShell> ds = aDocument.GetDocShell()) {
    nsCOMPtr<nsIDocumentViewer> viewer;
    ds->GetDocViewer(getter_AddRefs(viewer));
    while (viewer) {
      RefPtr<nsPresContext> pc = viewer->GetPresContext();
      if (pc && pc->GetPresShell()) {
        pc->GetPresShell()->SetNeverPainting(ds->IsInvisible());
      }
      nsDeviceContext* dc = pc ? pc->DeviceContext() : nullptr;
      if (dc) {
        nsView* v = viewer->FindContainerView();
        dc->Init(v ? v->GetNearestWidget(nullptr) : nullptr);
      }
      viewer = viewer->GetPreviousViewer();
    }
  }

  aDocument.EnumerateSubDocuments(EndSwapDocShellsForDocument);
  return CallState::Continue;
}

/* static */
void nsSubDocumentFrame::EndSwapDocShellsForViews(nsView* aSibling) {
  for (; aSibling; aSibling = aSibling->GetNextSibling()) {
    if (Document* doc = ::GetDocumentFromView(aSibling)) {
      ::EndSwapDocShellsForDocument(*doc);
    }
    nsIFrame* frame = aSibling->GetFrame();
    if (frame) {
      nsIFrame* parent = nsLayoutUtils::GetCrossDocParentFrameInProcess(frame);
      if (parent->HasAnyStateBits(NS_FRAME_IN_POPUP)) {
        nsIFrame::AddInPopupStateBitToDescendants(frame);
      } else {
        nsIFrame::RemoveInPopupStateBitFromDescendants(frame);
      }
      if (frame->HasInvalidFrameInSubtree()) {
        while (parent &&
               !parent->HasAnyStateBits(NS_FRAME_DESCENDANT_NEEDS_PAINT |
                                        NS_FRAME_IS_NONDISPLAY)) {
          parent->AddStateBits(NS_FRAME_DESCENDANT_NEEDS_PAINT);
          parent = nsLayoutUtils::GetCrossDocParentFrameInProcess(parent);
        }
      }
    }
  }
}

void nsSubDocumentFrame::EndSwapDocShells(nsIFrame* aOther) {
  nsSubDocumentFrame* other = static_cast<nsSubDocumentFrame*>(aOther);
  AutoWeakFrame weakThis(this);
  AutoWeakFrame weakOther(aOther);

  if (mInnerView) {
    EndSwapDocShellsForViews(mInnerView->GetFirstChild());
  }
  if (other->mInnerView) {
    EndSwapDocShellsForViews(other->mInnerView->GetFirstChild());
  }

  // Now make sure we reflow both frames, in case their contents
  // determine their size.
  // And repaint them, for good measure, in case there's nothing
  // interesting that happens during reflow.
  if (weakThis.IsAlive()) {
    PresShell()->FrameNeedsReflow(this, IntrinsicDirty::FrameAndAncestors,
                                  NS_FRAME_IS_DIRTY);
    InvalidateFrameSubtree();
    PropagateIsUnderHiddenEmbedderElement(
        PresShell()->IsUnderHiddenEmbedderElement() ||
        !StyleVisibility()->IsVisible());
  }
  if (weakOther.IsAlive()) {
    other->PresShell()->FrameNeedsReflow(
        other, IntrinsicDirty::FrameAndAncestors, NS_FRAME_IS_DIRTY);
    other->InvalidateFrameSubtree();
    other->PropagateIsUnderHiddenEmbedderElement(
        other->PresShell()->IsUnderHiddenEmbedderElement() ||
        !other->StyleVisibility()->IsVisible());
  }
}

void nsSubDocumentFrame::ClearDisplayItems() {
  if (auto* builder = nsLayoutUtils::GetRetainedDisplayListBuilder(this)) {
    DL_LOGD("nsSubDocumentFrame::ClearDisplayItems() %p", this);
    builder->ClearRetainedData();
  }
}

nsView* nsSubDocumentFrame::EnsureInnerView() {
  if (mInnerView) {
    return mInnerView;
  }

  // create, init, set the parent of the view
  nsView* outerView = GetView();
  NS_ASSERTION(outerView, "Must have an outer view already");
  nsRect viewBounds(0, 0, 0, 0);  // size will be fixed during reflow

  nsViewManager* viewMan = outerView->GetViewManager();
  nsView* innerView = viewMan->CreateView(viewBounds, outerView);
  if (!innerView) {
    NS_ERROR("Could not create inner view");
    return nullptr;
  }
  mInnerView = innerView;
  viewMan->InsertChild(outerView, innerView, nullptr, true);

  return mInnerView;
}

nsPoint nsSubDocumentFrame::GetExtraOffset() const {
  MOZ_ASSERT(mInnerView);
  return mInnerView->GetPosition();
}

void nsSubDocumentFrame::SubdocumentIntrinsicSizeOrRatioChanged() {
  const nsStylePosition* pos = StylePosition();
  bool dependsOnIntrinsics =
      !pos->mWidth.ConvertsToLength() || !pos->mHeight.ConvertsToLength();

  if (dependsOnIntrinsics || pos->mObjectFit != StyleObjectFit::Fill) {
    auto dirtyHint = dependsOnIntrinsics
                         ? IntrinsicDirty::FrameAncestorsAndDescendants
                         : IntrinsicDirty::None;
    PresShell()->FrameNeedsReflow(this, dirtyHint, NS_FRAME_IS_DIRTY);
    InvalidateFrame();
  }
}

// Return true iff |aManager| is a "temporary layer manager".  They're
// used for small software rendering tasks, like drawWindow.  That's
// currently implemented by a BasicLayerManager without a backing
// widget, and hence in non-retained mode.
nsDisplayRemote::nsDisplayRemote(nsDisplayListBuilder* aBuilder,
                                 nsSubDocumentFrame* aFrame)
    : nsPaintedDisplayItem(aBuilder, aFrame),
      mEventRegionsOverride(EventRegionsOverride::NoOverride) {
  const bool frameIsPointerEventsNone =
      aFrame->Style()->PointerEvents() == StylePointerEvents::None;
  if (aBuilder->IsInsidePointerEventsNoneDoc() || frameIsPointerEventsNone) {
    mEventRegionsOverride |= EventRegionsOverride::ForceEmptyHitRegion;
  }
  if (nsLayoutUtils::HasDocumentLevelListenersForApzAwareEvents(
          aFrame->PresShell())) {
    mEventRegionsOverride |= EventRegionsOverride::ForceDispatchToContent;
  }

  mPaintData = aFrame->GetRemotePaintData();
}

namespace mozilla {

void nsDisplayRemote::Paint(nsDisplayListBuilder* aBuilder, gfxContext* aCtx) {
  nsPresContext* pc = mFrame->PresContext();
  nsFrameLoader* fl = GetFrameLoader();
  if (pc->GetPrintSettings() && fl->IsRemoteFrame()) {
    // See the comment below in CreateWebRenderCommands() as for why doing this.
    fl->UpdatePositionAndSize(static_cast<nsSubDocumentFrame*>(mFrame));
  }

  DrawTarget* target = aCtx->GetDrawTarget();
  if (!target->IsRecording() || mPaintData.mTabId == 0) {
    NS_WARNING("Remote iframe not rendered");
    return;
  }

  // Rendering the inner document will apply a scale to account for its app
  // units per dev pixel ratio. We want to apply the inverse scaling using our
  // app units per dev pixel ratio, so that no actual scaling will be applied if
  // they match. For in-process rendering, nsSubDocumentFrame creates an
  // nsDisplayZoom item if the app units per dev pixel ratio changes.
  //
  // Similarly, rendering the inner document will scale up by the cross process
  // paint scale again, so we also need to account for that.
  const int32_t appUnitsPerDevPixel = pc->AppUnitsPerDevPixel();

  gfxContextMatrixAutoSaveRestore saveMatrix(aCtx);
  gfxFloat targetAuPerDev =
      gfxFloat(AppUnitsPerCSSPixel()) / aCtx->GetCrossProcessPaintScale();

  gfxFloat scale = targetAuPerDev / appUnitsPerDevPixel;
  aCtx->Multiply(gfxMatrix::Scaling(scale, scale));

  Rect destRect =
      NSRectToSnappedRect(GetContentRect(), targetAuPerDev, *target);
  target->DrawDependentSurface(mPaintData.mTabId, destRect);
}

bool nsDisplayRemote::CreateWebRenderCommands(
    mozilla::wr::DisplayListBuilder& aBuilder,
    mozilla::wr::IpcResourceUpdateQueue& aResources,
    const StackingContextHelper& aSc,
    mozilla::layers::RenderRootStateManager* aManager,
    nsDisplayListBuilder* aDisplayListBuilder) {
  if (!mPaintData.mLayersId.IsValid()) {
    return true;
  }

  nsPresContext* pc = mFrame->PresContext();
  nsFrameLoader* fl = GetFrameLoader();

  auto* subDocFrame = static_cast<nsSubDocumentFrame*>(mFrame);
  nsRect destRect = subDocFrame->GetDestRect();
  if (RefPtr<RemoteBrowser> remoteBrowser = fl->GetRemoteBrowser()) {
    if (pc->GetPrintSettings()) {
      // HACK(emilio): Usually we update sizing/positioning from
      // ReflowFinished(). Print documents have no incremental reflow at all
      // though, so we can't rely on it firing after a frame becomes remote.
      // Thus, if we're painting a remote frame, update its sizing and position
      // now.
      //
      // UpdatePositionAndSize() can cause havoc for non-remote frames but
      // luckily we don't care about those, so this is fine.
      fl->UpdatePositionAndSize(subDocFrame);
    }

    // Adjust mItemVisibleRect, which is relative to the reference frame, to be
    // relative to this frame.
    const nsRect buildingRect = GetBuildingRect() - ToReferenceFrame();
    Maybe<nsRect> visibleRect =
        buildingRect.EdgeInclusiveIntersection(destRect);
    if (visibleRect) {
      *visibleRect -= destRect.TopLeft();
    }

    // Generate an effects update notifying the browser it is visible
    MatrixScales scale = aSc.GetInheritedScale();

    ParentLayerToScreenScale2D transformToAncestorScale =
        ParentLayerToParentLayerScale(
            pc->GetPresShell() ? pc->GetPresShell()->GetCumulativeResolution()
                               : 1.f) *
        nsLayoutUtils::GetTransformToAncestorScaleCrossProcessForFrameMetrics(
            mFrame);

    aDisplayListBuilder->AddEffectUpdate(
        remoteBrowser, EffectsInfo::VisibleWithinRect(
                           visibleRect, scale, transformToAncestorScale));

    // Create a WebRenderRemoteData to notify the RemoteBrowser when it is no
    // longer visible
    RefPtr<WebRenderRemoteData> userData =
        aManager->CommandBuilder()
            .CreateOrRecycleWebRenderUserData<WebRenderRemoteData>(this,
                                                                   nullptr);
    userData->SetRemoteBrowser(remoteBrowser);
  }

  nscoord auPerDevPixel = pc->AppUnitsPerDevPixel();
  nsPoint layerOffset =
      aDisplayListBuilder->ToReferenceFrame(mFrame) + destRect.TopLeft();
  mOffset = LayoutDevicePoint::FromAppUnits(layerOffset, auPerDevPixel);

  destRect.MoveTo(0, 0);
  auto rect = LayoutDeviceRect::FromAppUnits(destRect, auPerDevPixel);
  rect += mOffset;

  aBuilder.PushIFrame(rect, !BackfaceIsHidden(),
                      mozilla::wr::AsPipelineId(mPaintData.mLayersId),
                      /*ignoreMissingPipelines*/ true);

  return true;
}

bool nsDisplayRemote::UpdateScrollData(
    mozilla::layers::WebRenderScrollData* aData,
    mozilla::layers::WebRenderLayerScrollData* aLayerData) {
  if (!mPaintData.mLayersId.IsValid()) {
    return true;
  }

  if (aLayerData) {
    aLayerData->SetReferentId(mPaintData.mLayersId);

    auto size = static_cast<nsSubDocumentFrame*>(mFrame)->GetSubdocumentSize();
    Matrix4x4 m = Matrix4x4::Translation(mOffset.x, mOffset.y, 0.0);
    aLayerData->SetTransform(m);
    aLayerData->SetEventRegionsOverride(mEventRegionsOverride);
    aLayerData->SetRemoteDocumentSize(LayerIntSize(size.width, size.height));
  }
  return true;
}

nsFrameLoader* nsDisplayRemote::GetFrameLoader() const {
  return static_cast<nsSubDocumentFrame*>(mFrame)->FrameLoader();
}

}  // namespace mozilla