/*
 * Copyright (C) 2011 Google Inc. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are
 * met:
 *
 *     * Redistributions of source code must retain the above copyright
 * notice, this list of conditions and the following disclaimer.
 *     * Neither the name of Google Inc. nor the names of its
 * contributors may be used to endorse or promote products derived from
 * this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#ifndef ShadowRoot_h
#define ShadowRoot_h

#include "core/CoreExport.h"
#include "core/dom/ContainerNode.h"
#include "core/dom/DocumentFragment.h"
#include "core/dom/Element.h"
#include "core/dom/TreeScope.h"

namespace blink {

class Document;
class ElementShadow;
class ExceptionState;
class HTMLShadowElement;
class HTMLSlotElement;
class InsertionPoint;
class ShadowRootRareDataV0;
class SlotAssignment;
class StyleSheetList;

enum class ShadowRootType { UserAgent, V0, Open, Closed };

class CORE_EXPORT ShadowRoot final : public DocumentFragment, public TreeScope {
  DEFINE_WRAPPERTYPEINFO();
  USING_GARBAGE_COLLECTED_MIXIN(ShadowRoot);

 public:
  // FIXME: Current implementation does not work well if a shadow root is
  // dynamically created.  So multiple shadow subtrees in several elements are
  // prohibited.
  // See https://github.com/w3c/webcomponents/issues/102 and
  // http://crbug.com/234020
  static ShadowRoot* create(Document& document, ShadowRootType type) {
    return new ShadowRoot(document, type);
  }

  // Disambiguate between Node and TreeScope hierarchies; TreeScope's
  // implementation is simpler.
  using TreeScope::document;
  using TreeScope::getElementById;

  // Make protected methods from base class public here.
  using TreeScope::setDocument;
  using TreeScope::setParentTreeScope;

  Element& host() const {
    DCHECK(parentOrShadowHostNode());
    return *toElement(parentOrShadowHostNode());
  }
  ElementShadow* owner() const { return host().shadow(); }
  ShadowRootType type() const { return static_cast<ShadowRootType>(m_type); }
  String mode() const {
    return (type() == ShadowRootType::V0 || type() == ShadowRootType::Open)
               ? "open"
               : "closed";
  };

  bool isOpenOrV0() const {
    return type() == ShadowRootType::V0 || type() == ShadowRootType::Open;
  }
  bool isV1() const {
    return type() == ShadowRootType::Open || type() == ShadowRootType::Closed;
  }

  void attachLayoutTree(const AttachContext& = AttachContext()) override;
  void detachLayoutTree(const AttachContext& = AttachContext()) override;

  InsertionNotificationRequest insertedInto(ContainerNode*) override;
  void removedFrom(ContainerNode*) override;

  // For V0
  ShadowRoot* youngerShadowRoot() const;
  ShadowRoot* olderShadowRoot() const;
  ShadowRoot* olderShadowRootForBindings() const;
  void setYoungerShadowRoot(ShadowRoot&);
  void setOlderShadowRoot(ShadowRoot&);
  bool isYoungest() const { return !youngerShadowRoot(); }
  bool isOldest() const { return !olderShadowRoot(); }
  bool containsShadowElements() const;
  bool containsContentElements() const;
  bool containsInsertionPoints() const {
    return containsShadowElements() || containsContentElements();
  }
  unsigned descendantShadowElementCount() const;
  HTMLShadowElement* shadowInsertionPointOfYoungerShadowRoot() const;
  void setShadowInsertionPointOfYoungerShadowRoot(HTMLShadowElement*);
  void didAddInsertionPoint(InsertionPoint*);
  void didRemoveInsertionPoint(InsertionPoint*);
  const HeapVector<Member<InsertionPoint>>& descendantInsertionPoints();

  // For Internals, don't use this.
  unsigned childShadowRootCount() const { return m_childShadowRootCount; }
  unsigned numberOfStyles() const { return m_numberOfStyles; }

  void recalcStyle(StyleRecalcChange);

  void registerScopedHTMLStyleChild();
  void unregisterScopedHTMLStyleChild();

  SlotAssignment& ensureSlotAssignment();

  void distributeV1();

  Element* activeElement() const;

  String innerHTML() const;
  void setInnerHTML(const String&, ExceptionState&);

  Node* cloneNode(bool, ExceptionState&);

  void setDelegatesFocus(bool flag) { m_delegatesFocus = flag; }
  bool delegatesFocus() const { return m_delegatesFocus; }

  bool containsShadowRoots() const { return m_childShadowRootCount; }

  StyleSheetList& styleSheets();
  void setStyleSheets(StyleSheetList* styleSheetList) {
    m_styleSheetList = styleSheetList;
  }

  DECLARE_VIRTUAL_TRACE();

  DECLARE_VIRTUAL_TRACE_WRAPPERS();

 private:
  ShadowRoot(Document&, ShadowRootType);
  ~ShadowRoot() override;

  void childrenChanged(const ChildrenChange&) override;

  ShadowRootRareDataV0& ensureShadowRootRareDataV0();

  void addChildShadowRoot() { ++m_childShadowRootCount; }
  void removeChildShadowRoot() {
    DCHECK_GT(m_childShadowRootCount, 0u);
    --m_childShadowRootCount;
  }
  void invalidateDescendantInsertionPoints();

  // ShadowRoots should never be cloned.
  Node* cloneNode(bool) override { return nullptr; }

  Member<ShadowRootRareDataV0> m_shadowRootRareDataV0;
  Member<StyleSheetList> m_styleSheetList;
  Member<SlotAssignment> m_slotAssignment;
  unsigned m_numberOfStyles : 14;
  unsigned m_childShadowRootCount : 13;
  unsigned m_type : 2;
  unsigned m_registeredWithParentShadowRoot : 1;
  unsigned m_descendantInsertionPointsIsValid : 1;
  unsigned m_delegatesFocus : 1;
};

inline Element* ShadowRoot::activeElement() const {
  return adjustedFocusedElement();
}

inline ShadowRoot* Element::shadowRootIfV1() const {
  ShadowRoot* root = this->shadowRoot();
  if (root && root->isV1())
    return root;
  return nullptr;
}

DEFINE_NODE_TYPE_CASTS(ShadowRoot, isShadowRoot());
DEFINE_TYPE_CASTS(ShadowRoot,
                  TreeScope,
                  treeScope,
                  treeScope->rootNode().isShadowRoot(),
                  treeScope.rootNode().isShadowRoot());
DEFINE_TYPE_CASTS(TreeScope, ShadowRoot, shadowRoot, true, true);

CORE_EXPORT std::ostream& operator<<(std::ostream&, const ShadowRootType&);

}  // namespace blink

#endif  // ShadowRoot_h