layout/base/nsLayoutHistoryState.cpp

   1 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* vim: set ts=8 sts=2 et sw=2 tw=80: */
   3 /* This Source Code Form is subject to the terms of the Mozilla Public
   4  * License, v. 2.0. If a copy of the MPL was not distributed with this
   5  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   6
   7 /*
   8  * container for information saved in session history when the document
   9  * is not
  10  */
  11
  12 #include "nsILayoutHistoryState.h"
  13 #include "nsWeakReference.h"
  14 #include "mozilla/PresState.h"
  15 #include "mozilla/Attributes.h"
  16 #include "mozilla/UniquePtr.h"
  17 #include "nsTHashMap.h"
  18
  19 using namespace mozilla;
  20
  21 class nsLayoutHistoryState final : public nsILayoutHistoryState,
  22                                    public nsSupportsWeakReference {
  23  public:
  24   nsLayoutHistoryState() : mScrollPositionOnly(false) {}
  25
  26   NS_DECL_ISUPPORTS
  27   NS_DECL_NSILAYOUTHISTORYSTATE
  28
  29  private:
  30   ~nsLayoutHistoryState() = default;
  31   bool mScrollPositionOnly;
  32
  33   nsTHashMap<nsCString, UniquePtr<PresState>> mStates;
  34 };
  35
  36 already_AddRefed<nsILayoutHistoryState> NS_NewLayoutHistoryState() {
  37   RefPtr<nsLayoutHistoryState> state = new nsLayoutHistoryState();
  38   return state.forget();
  39 }
  40
  41 NS_IMPL_ISUPPORTS(nsLayoutHistoryState, nsILayoutHistoryState,
  42                   nsISupportsWeakReference)
  43
  44 NS_IMETHODIMP
  45 nsLayoutHistoryState::GetHasStates(bool* aHasStates) {
  46   *aHasStates = HasStates();
  47   return NS_OK;
  48 }
  49
  50 NS_IMETHODIMP
  51 nsLayoutHistoryState::GetKeys(nsTArray<nsCString>& aKeys) {
  52   if (!HasStates()) {
  53     return NS_ERROR_FAILURE;
  54   }
  55
  56   AppendToArray(aKeys, mStates.Keys());
  57
  58   return NS_OK;
  59 }
  60
  61 NS_IMETHODIMP
  62 nsLayoutHistoryState::GetPresState(const nsACString& aKey, float* aScrollX,
  63                                    float* aScrollY,
  64                                    bool* aAllowScrollOriginDowngrade,
  65                                    float* aRes) {
  66   PresState* state = GetState(nsCString(aKey));
  67
  68   if (!state) {
  69     return NS_ERROR_FAILURE;
  70   }
  71
  72   *aScrollX = state->scrollState().x;
  73   *aScrollY = state->scrollState().y;
  74   *aAllowScrollOriginDowngrade = state->allowScrollOriginDowngrade();
  75   *aRes = state->resolution();
  76
  77   return NS_OK;
  78 }
  79
  80 NS_IMETHODIMP
  81 nsLayoutHistoryState::AddNewPresState(const nsACString& aKey, float aScrollX,
  82                                       float aScrollY,
  83                                       bool aAllowScrollOriginDowngrade,
  84                                       float aRes) {
  85   UniquePtr<PresState> newState = NewPresState();
  86   newState->scrollState() = nsPoint(aScrollX, aScrollY);
  87   newState->allowScrollOriginDowngrade() = aAllowScrollOriginDowngrade;
  88   newState->resolution() = aRes;
  89
  90   mStates.InsertOrUpdate(nsCString(aKey), std::move(newState));
  91
  92   return NS_OK;
  93 }
  94
  95 void nsLayoutHistoryState::AddState(const nsCString& aStateKey,
  96                                     UniquePtr<PresState> aState) {
  97   mStates.InsertOrUpdate(aStateKey, std::move(aState));
  98 }
  99
 100 PresState* nsLayoutHistoryState::GetState(const nsCString& aKey) {
 101   auto statePtr = mStates.Lookup(aKey);
 102   if (!statePtr) {
 103     return nullptr;
 104   }
 105   PresState* state = statePtr->get();
 106
 107   if (mScrollPositionOnly) {
 108     // Ensure any state that shouldn't be restored is removed
 109     state->contentData() = void_t();
 110     state->disabledSet() = false;
 111   }
 112
 113   return state;
 114 }
 115
 116 void nsLayoutHistoryState::RemoveState(const nsCString& aKey) {
 117   mStates.Remove(aKey);
 118 }
 119
 120 bool nsLayoutHistoryState::HasStates() { return mStates.Count() != 0; }
 121
 122 void nsLayoutHistoryState::SetScrollPositionOnly(const bool aFlag) {
 123   mScrollPositionOnly = aFlag;
 124 }
 125
 126 void nsLayoutHistoryState::ResetScrollState() {
 127   for (const auto& state : mStates.Values()) {
 128     if (state) {
 129       state->scrollState() = nsPoint(0, 0);
 130     }
 131   }
 132 }
 133
 134 void nsLayoutHistoryState::GetContents(bool* aScrollPositionOnly,
 135                                        nsTArray<nsCString>& aKeys,
 136                                        nsTArray<mozilla::PresState>& aStates) {
 137   *aScrollPositionOnly = mScrollPositionOnly;
 138   aKeys.SetCapacity(mStates.Count());
 139   aStates.SetCapacity(mStates.Count());
 140   for (const auto& entry : mStates) {
 141     aKeys.AppendElement(entry.GetKey());
 142     aStates.AppendElement(*(entry.GetData().get()));
 143   }
 144 }
 145
 146 void nsLayoutHistoryState::Reset() {
 147   mScrollPositionOnly = false;
 148   mStates.Clear();
 149 }
 150
 151 namespace mozilla {
 152 UniquePtr<PresState> NewPresState() {
 153   return MakeUnique<PresState>(
 154       /* contentData */ mozilla::void_t(),
 155       /* scrollState */ nsPoint(0, 0),
 156       /* allowScrollOriginDowngrade */ true,
 157       /* resolution */ 1.0,
 158       /* disabledSet */ false,
 159       /* disabled */ false,
 160       /* droppedDown */ false);
 161 }
 162 }  // namespace mozilla