/* -*- 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/. */

#include "BrowsingContext.h"

#include "mozilla/dom/ChromeBrowsingContext.h"

#include "mozilla/dom/BrowsingContextBinding.h"

#include "mozilla/dom/ContentChild.h"

#include "mozilla/Assertions.h"

#include "mozilla/ClearOnShutdown.h"

#include "mozilla/Logging.h"

#include "mozilla/StaticPtr.h"

#include "nsDataHashtable.h"

#include "nsRefPtrHashtable.h"

#include "nsIDocShell.h"

#include "nsContentUtils.h"

#include "nsThreadUtils.h"

namespace mozilla {

namespace dom {

static LazyLogModule gBrowsingContextLog("BrowsingContext");

static StaticAutoPtr<BrowsingContext::Children> sRootBrowsingContexts;

static StaticAutoPtr<nsDataHashtable<nsUint64HashKey, BrowsingContext*>>

  sBrowsingContexts;

// TODO(farre): This duplicates some of the work performed by the

// bfcache. This should be unified. [Bug 1471601]

static StaticAutoPtr<nsRefPtrHashtable<nsUint64HashKey, BrowsingContext>>

  sCachedBrowsingContexts;

/* static */ void

BrowsingContext::Init()

{

  if (!sRootBrowsingContexts) {

    sRootBrowsingContexts = new BrowsingContext::Children();

    ClearOnShutdown(&sRootBrowsingContexts);

  }

  if (!sBrowsingContexts) {

    sBrowsingContexts =

      new nsDataHashtable<nsUint64HashKey, BrowsingContext*>();

    ClearOnShutdown(&sBrowsingContexts);

  }

  if (!sCachedBrowsingContexts) {

    sCachedBrowsingContexts =

      new nsRefPtrHashtable<nsUint64HashKey, BrowsingContext>();

    ClearOnShutdown(&sCachedBrowsingContexts);

  }

}

/* static */ LogModule*

BrowsingContext::GetLog()

{

  return gBrowsingContextLog;

}

/* static */ already_AddRefed<BrowsingContext>

BrowsingContext::Get(uint64_t aId)

{

  RefPtr<BrowsingContext> abc = sBrowsingContexts->Get(aId);

  return abc.forget();

}

/* static */ already_AddRefed<BrowsingContext>

BrowsingContext::Create(nsIDocShell* aDocShell)

{

  RefPtr<BrowsingContext> context;

  if (XRE_IsParentProcess()) {

    context = new ChromeBrowsingContext(aDocShell);

  } else {

    // TODO(farre): will we ever create BrowsingContexts on processes

    // other than content and parent?

    MOZ_ASSERT(XRE_IsContentProcess());

    context = new BrowsingContext(aDocShell);

  }

  return context.forget();

}

BrowsingContext::BrowsingContext(nsIDocShell* aDocShell)

  : mBrowsingContextId(nsContentUtils::GenerateBrowsingContextId())

  , mDocShell(aDocShell)

{

  sBrowsingContexts->Put(mBrowsingContextId, this);

}

BrowsingContext::BrowsingContext(uint64_t aBrowsingContextId,

                const nsAString& aName)

  : mBrowsingContextId(aBrowsingContextId)

  , mName(aName)

{

  sBrowsingContexts->Put(mBrowsingContextId, this);

}

void

BrowsingContext::Attach(BrowsingContext* aParent)

{

  if (isInList()) {

    MOZ_LOG(GetLog(),

            LogLevel::Debug,

            ("%s: Connecting already existing 0x%08" PRIx64 " to 0x%08" PRIx64,

             XRE_IsParentProcess() ? "Parent" : "Child",

             Id(),

             aParent ? aParent->Id() : 0));

    MOZ_DIAGNOSTIC_ASSERT(sBrowsingContexts->Contains(Id()));

    MOZ_DIAGNOSTIC_ASSERT(!IsCached());

    return;

  }

  bool wasCached = sCachedBrowsingContexts->Remove(Id());

  MOZ_LOG(GetLog(),

          LogLevel::Debug,

          ("%s: %s 0x%08" PRIx64 " to 0x%08" PRIx64,

           XRE_IsParentProcess() ? "Parent" : "Child",

           wasCached ? "Re-connecting" : "Connecting",

           Id(),

           aParent ? aParent->Id() : 0));

  auto* children = aParent ? &aParent->mChildren : sRootBrowsingContexts.get();

  children->insertBack(this);

  mParent = aParent;

  if (!XRE_IsContentProcess()) {

    return;

  }

  auto cc = ContentChild::GetSingleton();

  MOZ_DIAGNOSTIC_ASSERT(cc);

  cc->SendAttachBrowsingContext(

    BrowsingContextId(mParent ? mParent->Id() : 0),

    BrowsingContextId(Id()),

    mName);

}

void

BrowsingContext::Detach()

{

  RefPtr<BrowsingContext> kungFuDeathGrip(this);

  if (sCachedBrowsingContexts) {

    sCachedBrowsingContexts->Remove(Id());

  }

  if (!isInList()) {

    MOZ_LOG(GetLog(),

            LogLevel::Debug,

            ("%s: Detaching already detached 0x%08" PRIx64,

             XRE_IsParentProcess() ? "Parent" : "Child",

             Id()));

    return;

  }

  MOZ_LOG(GetLog(),

          LogLevel::Debug,

          ("%s: Detaching 0x%08" PRIx64 " from 0x%08" PRIx64,

           XRE_IsParentProcess() ? "Parent" : "Child",

           Id(),

           mParent ? mParent->Id() : 0));

  remove();

  if (!XRE_IsContentProcess()) {

    return;

  }

  auto cc = ContentChild::GetSingleton();

  MOZ_DIAGNOSTIC_ASSERT(cc);

  cc->SendDetachBrowsingContext(BrowsingContextId(Id()),

                                false /* aMoveToBFCache */);

}

void

BrowsingContext::CacheChildren()

{

  if (mChildren.isEmpty()) {

    return;

  }

  MOZ_LOG(GetLog(),

          LogLevel::Debug,

          ("%s: Caching children of 0x%08" PRIx64 "",

           XRE_IsParentProcess() ? "Parent" : "Child",

           Id()));

  while (!mChildren.isEmpty()) {

    RefPtr<BrowsingContext> child = mChildren.popFirst();

    sCachedBrowsingContexts->Put(child->Id(), child);

  }

  if (!XRE_IsContentProcess()) {

    return;

  }

  auto cc = ContentChild::GetSingleton();

  MOZ_DIAGNOSTIC_ASSERT(cc);

  cc->SendDetachBrowsingContext(BrowsingContextId(Id()),

                                true /* aMoveToBFCache */);

}

bool

BrowsingContext::IsCached()

{

  return sCachedBrowsingContexts->Contains(Id());

}

void

BrowsingContext::GetChildren(nsTArray<RefPtr<BrowsingContext>>& aChildren)

{

  for (BrowsingContext* context : mChildren) {

    aChildren.AppendElement(context);

  }

}

/* static */ void

BrowsingContext::GetRootBrowsingContexts(nsTArray<RefPtr<BrowsingContext>>& aBrowsingContexts)

{

  for (BrowsingContext* context : *sRootBrowsingContexts) {

    aBrowsingContexts.AppendElement(context);

  }

}

BrowsingContext::~BrowsingContext()

{

  MOZ_DIAGNOSTIC_ASSERT(!isInList());

  if (sBrowsingContexts) {

    sBrowsingContexts->Remove(mBrowsingContextId);

  }

}

nsISupports*

BrowsingContext::GetParentObject() const

{

  return xpc::NativeGlobal(xpc::PrivilegedJunkScope());

}

JSObject*

BrowsingContext::WrapObject(JSContext* aCx,

                            JS::Handle<JSObject*> aGivenProto)

{

  return BrowsingContext_Binding::Wrap(aCx, this, aGivenProto);

}

static void

ImplCycleCollectionUnlink(BrowsingContext::Children& aField)

{

  aField.clear();

}

static void

ImplCycleCollectionTraverse(nsCycleCollectionTraversalCallback& aCallback,

                            BrowsingContext::Children& aField,

                            const char* aName,

                            uint32_t aFlags = 0)

{

  for (BrowsingContext* aContext : aField) {

    aCallback.NoteNativeChild(aContext,

                              NS_CYCLE_COLLECTION_PARTICIPANT(BrowsingContext));

  }

}

NS_IMPL_CYCLE_COLLECTION_CLASS(BrowsingContext)

NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN(BrowsingContext)

  NS_IMPL_CYCLE_COLLECTION_UNLINK(mDocShell, mChildren)

  if (XRE_IsParentProcess()) {

    ChromeBrowsingContext::Cast(tmp)->Unlink();

  }

  NS_IMPL_CYCLE_COLLECTION_UNLINK_PRESERVED_WRAPPER

NS_IMPL_CYCLE_COLLECTION_UNLINK_END

NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN(BrowsingContext)

  NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mDocShell, mChildren)

  if (XRE_IsParentProcess()) {

    ChromeBrowsingContext::Cast(tmp)->Traverse(cb);

  }

NS_IMPL_CYCLE_COLLECTION_TRAVERSE_END

NS_IMPL_CYCLE_COLLECTION_TRACE_WRAPPERCACHE(BrowsingContext)

NS_IMPL_CYCLE_COLLECTION_ROOT_NATIVE(BrowsingContext, AddRef)

NS_IMPL_CYCLE_COLLECTION_UNROOT_NATIVE(BrowsingContext, Release)

} // namespace dom

} // namespace mozilla