third_party/WebKit/Source/core/style/StyleInheritedVariables.h

// Copyright 2015 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef StyleInheritedVariables_h
#define StyleInheritedVariables_h

#include "core/css/CSSValue.h"
#include "core/css/CSSVariableData.h"
#include "wtf/Forward.h"
#include "wtf/HashMap.h"
#include "wtf/RefCounted.h"
#include "wtf/text/AtomicStringHash.h"

namespace blink {

class StyleInheritedVariables : public RefCounted<StyleInheritedVariables> {
public:
    static PassRefPtr<StyleInheritedVariables> create() { return adoptRef(new StyleInheritedVariables()); }

    PassRefPtr<StyleInheritedVariables> copy() { return adoptRef(new StyleInheritedVariables(*this)); }

    bool operator==(const StyleInheritedVariables& other) const;
    bool operator!=(const StyleInheritedVariables& other) const { return !(*this == other); }

    void setVariable(const AtomicString& name, PassRefPtr<CSSVariableData> value) { m_data.set(name, std::move(value)); }
    CSSVariableData* getVariable(const AtomicString& name) const;
    void removeVariable(const AtomicString&);

    void setRegisteredVariable(const AtomicString&, const CSSValue*);
    CSSValue* registeredVariable(const AtomicString&) const;

    // This map will contain null pointers if variables are invalid due to
    // cycles or referencing invalid variables without using a fallback.
    // Note that this method is slow as a new map is constructed.
    std::unique_ptr<HashMap<AtomicString, RefPtr<CSSVariableData>>> getVariables() const;
private:
    StyleInheritedVariables()
        : m_root(nullptr)
        { }
    StyleInheritedVariables(StyleInheritedVariables& other);

    friend class CSSVariableResolver;

    HashMap<AtomicString, RefPtr<CSSVariableData>> m_data;
    HashMap<AtomicString, Persistent<CSSValue>> m_registeredData;
    RefPtr<StyleInheritedVariables> m_root;
};

} // namespace blink

#endif // StyleInheritedVariables_h