/*
 * (C) 1999-2003 Lars Knoll (knoll@kde.org)
 * (C) 2002-2003 Dirk Mueller (mueller@kde.org)
 * Copyright (C) 2002-2021 Apple Inc. All rights reserved.
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Library General Public
 * License as published by the Free Software Foundation; either
 * version 2 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Library General Public License for more details.
 *
 * You should have received a copy of the GNU Library General Public License
 * along with this library; see the file COPYING.LIB.  If not, write to
 * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
 * Boston, MA 02110-1301, USA.
 */

#pragma once

#include "CSSSelectorList.h"
#include "CSSVariableData.h"
#include "CompiledSelector.h"
#include "ContainerQuery.h"
#include "FontFeatureValues.h"
#include "FontPaletteValues.h"
#include "MediaQuery.h"
#include "StyleRuleType.h"
#include <map>
#include <variant>
#include <wtf/Ref.h>
#include <wtf/RefPtr.h>
#include <wtf/TypeCasts.h>
#include <wtf/UniqueArray.h>

namespace WebCore {

class CSSRule;
class CSSGroupingRule;
class CSSStyleRule;
class CSSStyleSheet;
class MutableStyleProperties;
class StyleRuleKeyframe;
class StyleProperties;

using CascadeLayerName = Vector<AtomString>;
    
DECLARE_ALLOCATOR_WITH_HEAP_IDENTIFIER(StyleRuleBase);
class StyleRuleBase : public RefCounted<StyleRuleBase> {
    WTF_MAKE_STRUCT_FAST_ALLOCATED_WITH_HEAP_IDENTIFIER(StyleRuleBase);
public:
    StyleRuleType type() const { return static_cast<StyleRuleType>(m_type); }
    
    bool isCharsetRule() const { return type() == StyleRuleType::Charset; }
    bool isCounterStyleRule() const { return type() == StyleRuleType::CounterStyle; }
    bool isFontFaceRule() const { return type() == StyleRuleType::FontFace; }
    bool isFontPaletteValuesRule() const { return type() == StyleRuleType::FontPaletteValues; }
    bool isFontFeatureValuesRule() const { return type() == StyleRuleType::FontFeatureValues; }
    bool isFontFeatureValuesBlockRule() const { return type() == StyleRuleType::FontFeatureValuesBlock; }
    bool isKeyframesRule() const { return type() == StyleRuleType::Keyframes; }
    bool isKeyframeRule() const { return type() == StyleRuleType::Keyframe; }
    bool isNamespaceRule() const { return type() == StyleRuleType::Namespace; }
    bool isMediaRule() const { return type() == StyleRuleType::Media; }
    bool isPageRule() const { return type() == StyleRuleType::Page; }
    bool isStyleRule() const { return type() == StyleRuleType::Style || type() == StyleRuleType::StyleWithNesting; }
    bool isStyleRuleWithNesting() const { return type() == StyleRuleType::StyleWithNesting; }
    bool isGroupRule() const { return type() == StyleRuleType::Media || type() == StyleRuleType::Supports || type() == StyleRuleType::LayerBlock || type() == StyleRuleType::Container; }
    bool isSupportsRule() const { return type() == StyleRuleType::Supports; }
    bool isImportRule() const { return type() == StyleRuleType::Import; }
    bool isLayerRule() const { return type() == StyleRuleType::LayerBlock || type() == StyleRuleType::LayerStatement; }
    bool isContainerRule() const { return type() == StyleRuleType::Container; }
    bool isPropertyRule() const { return type() == StyleRuleType::Property; }

    Ref<StyleRuleBase> copy() const;

    Ref<CSSRule> createCSSOMWrapper(CSSStyleSheet& parentSheet) const;
    Ref<CSSRule> createCSSOMWrapper(CSSGroupingRule& parentRule) const;
    Ref<CSSRule> createCSSOMWrapper(CSSStyleRule& parentRule) const;

    // This is only needed to support getMatchedCSSRules.
    Ref<CSSRule> createCSSOMWrapper() const;

    WEBCORE_EXPORT void operator delete(StyleRuleBase*, std::destroying_delete_t);

protected:
    explicit StyleRuleBase(StyleRuleType, bool hasDocumentSecurityOrigin = false);
    StyleRuleBase(const StyleRuleBase&);

    bool hasDocumentSecurityOrigin() const { return m_hasDocumentSecurityOrigin; }
    void setType(StyleRuleType type) { m_type = static_cast<unsigned>(type); }

private:
    template<typename Visitor> constexpr decltype(auto) visitDerived(Visitor&&);
    template<typename Visitor> constexpr decltype(auto) visitDerived(Visitor&&) const;

    Ref<CSSRule> createCSSOMWrapper(CSSStyleSheet* parentSheet, CSSRule* parentRule) const;

    unsigned m_type : 5; // StyleRuleType

    // This is only needed to support getMatchedCSSRules.
    unsigned m_hasDocumentSecurityOrigin : 1;
};

DECLARE_ALLOCATOR_WITH_HEAP_IDENTIFIER(StyleRule);
class StyleRule : public StyleRuleBase {
    WTF_MAKE_STRUCT_FAST_ALLOCATED_WITH_HEAP_IDENTIFIER(StyleRule);
public:
    static Ref<StyleRule> create(Ref<StyleProperties>&&, bool hasDocumentSecurityOrigin, CSSSelectorList&&);
    Ref<StyleRule> copy() const;
    ~StyleRule();

    const CSSSelectorList& selectorList() const { return m_selectorList; }
    const StyleProperties& properties() const { return m_properties.get(); }
    MutableStyleProperties& mutableProperties();

    bool isSplitRule() const { return m_isSplitRule; }
    void markAsSplitRule() { m_isSplitRule = true; }
    bool isLastRuleInSplitRule() const { return m_isLastRuleInSplitRule; }
    void markAsLastRuleInSplitRule() { m_isLastRuleInSplitRule = true; }

    using StyleRuleBase::hasDocumentSecurityOrigin;

    void wrapperAdoptSelectorList(CSSSelectorList&&);

    Vector<Ref<StyleRule>> splitIntoMultipleRulesWithMaximumSelectorComponentCount(unsigned) const;

#if ENABLE(CSS_SELECTOR_JIT)
    CompiledSelector& compiledSelectorForListIndex(unsigned index) const;
    void releaseCompiledSelectors() const { m_compiledSelectors = nullptr; }
#endif

    static unsigned averageSizeInBytes();
    void setProperties(Ref<StyleProperties>&&);

protected:
    StyleRule(Ref<StyleProperties>&&, bool hasDocumentSecurityOrigin, CSSSelectorList&&);
    StyleRule(const StyleRule&);

private:
    static Ref<StyleRule> createForSplitting(const Vector<const CSSSelector*>&, Ref<StyleProperties>&&, bool hasDocumentSecurityOrigin);

    bool m_isSplitRule { false };
    bool m_isLastRuleInSplitRule { false };

    mutable Ref<StyleProperties> m_properties;
    CSSSelectorList m_selectorList;
#if ENABLE(CSS_SELECTOR_JIT)
    mutable UniqueArray<CompiledSelector> m_compiledSelectors;
#endif
};

DECLARE_ALLOCATOR_WITH_HEAP_IDENTIFIER(StyleRuleWithNesting);
class StyleRuleWithNesting final : public StyleRule {
    WTF_MAKE_STRUCT_FAST_ALLOCATED_WITH_HEAP_IDENTIFIER(StyleRuleWithNesting);
public:
    static Ref<StyleRuleWithNesting> create(Ref<StyleProperties>&&, bool hasDocumentSecurityOrigin, CSSSelectorList&&, Vector<Ref<StyleRuleBase>>&& nestedRules);
    static Ref<StyleRuleWithNesting> create(StyleRule&&);
    Ref<StyleRuleWithNesting> copy() const;
    ~StyleRuleWithNesting();

    const Vector<Ref<StyleRuleBase>>& nestedRules() const { return m_nestedRules; }
    Vector<Ref<StyleRuleBase>>& nestedRules() { return m_nestedRules; }
    const CSSSelectorList& originalSelectorList() const { return m_originalSelectorList; }
    void wrapperAdoptOriginalSelectorList(CSSSelectorList&&);

protected:
    StyleRuleWithNesting(const StyleRuleWithNesting&);

private:
    StyleRuleWithNesting(Ref<StyleProperties>&&, bool hasDocumentSecurityOrigin, CSSSelectorList&&, Vector<Ref<StyleRuleBase>>&& nestedRules);
    StyleRuleWithNesting(StyleRule&&);

    Vector<Ref<StyleRuleBase>> m_nestedRules;
    CSSSelectorList m_originalSelectorList;
};

class StyleRuleFontFace final : public StyleRuleBase {
public:
    static Ref<StyleRuleFontFace> create(Ref<StyleProperties>&& properties) { return adoptRef(*new StyleRuleFontFace(WTFMove(properties))); }
    ~StyleRuleFontFace();

    const StyleProperties& properties() const { return m_properties; }
    MutableStyleProperties& mutableProperties();

    Ref<StyleRuleFontFace> copy() const { return adoptRef(*new StyleRuleFontFace(*this)); }

private:
    explicit StyleRuleFontFace(Ref<StyleProperties>&&);
    StyleRuleFontFace(const StyleRuleFontFace&);

    Ref<StyleProperties> m_properties;
};

class StyleRuleFontPaletteValues final : public StyleRuleBase {
public:
    static Ref<StyleRuleFontPaletteValues> create(const AtomString& name, const AtomString& fontFamily, std::optional<FontPaletteIndex> basePalette, Vector<FontPaletteValues::OverriddenColor>&&);

    const AtomString& name() const { return m_name; }
    const AtomString& fontFamily() const { return m_fontFamily; }
    const FontPaletteValues& fontPaletteValues() const { return m_fontPaletteValues; }
    std::optional<FontPaletteIndex> basePalette() const { return m_fontPaletteValues.basePalette(); }
    const Vector<FontPaletteValues::OverriddenColor>& overrideColors() const { return m_fontPaletteValues.overrideColors(); }

    Ref<StyleRuleFontPaletteValues> copy() const { return adoptRef(*new StyleRuleFontPaletteValues(*this)); }

private:
    StyleRuleFontPaletteValues(const AtomString& name, const AtomString& fontFamily, std::optional<FontPaletteIndex> basePalette, Vector<FontPaletteValues::OverriddenColor>&& overrideColors);
    StyleRuleFontPaletteValues(const StyleRuleFontPaletteValues&) = default;

    AtomString m_name;
    AtomString m_fontFamily;
    FontPaletteValues m_fontPaletteValues;
};

class StyleRuleFontFeatureValuesBlock final : public StyleRuleBase {
public:
    static Ref<StyleRuleFontFeatureValuesBlock> create(FontFeatureValuesType type, const Vector<FontFeatureValuesTag>& tags)
    {
        return adoptRef(*new StyleRuleFontFeatureValuesBlock(type, tags));
    }
    
    ~StyleRuleFontFeatureValuesBlock() = default;

    FontFeatureValuesType fontFeatureValuesType() const { return m_type; }

    const Vector<FontFeatureValuesTag>& tags() const { return m_tags; }

    Ref<StyleRuleFontFeatureValuesBlock> copy() const { return adoptRef(*new StyleRuleFontFeatureValuesBlock(*this)); }
private:
    StyleRuleFontFeatureValuesBlock(FontFeatureValuesType, const Vector<FontFeatureValuesTag>&);
    StyleRuleFontFeatureValuesBlock(const StyleRuleFontFeatureValuesBlock&) = default;

    FontFeatureValuesType m_type;
    Vector<FontFeatureValuesTag> m_tags;
};

class StyleRuleFontFeatureValues final : public StyleRuleBase {
public:
    static Ref<StyleRuleFontFeatureValues> create(const Vector<AtomString>& fontFamilies, Ref<FontFeatureValues>&&);
    
    ~StyleRuleFontFeatureValues() = default;

    const Vector<AtomString>& fontFamilies() const { return m_fontFamilies; }

    Ref<FontFeatureValues> value() const { return m_value; }

    Ref<StyleRuleFontFeatureValues> copy() const { return adoptRef(*new StyleRuleFontFeatureValues(*this)); }

private:
    StyleRuleFontFeatureValues(const Vector<AtomString>&, Ref<FontFeatureValues>&&);
    StyleRuleFontFeatureValues(const StyleRuleFontFeatureValues&) = default;

    Vector<AtomString> m_fontFamilies;
    Ref<FontFeatureValues> m_value;
};

class StyleRulePage final : public StyleRuleBase {
public:
    static Ref<StyleRulePage> create(Ref<StyleProperties>&&, CSSSelectorList&&);

    ~StyleRulePage();

    const CSSSelector* selector() const { return m_selectorList.first(); }    
    const StyleProperties& properties() const { return m_properties; }
    MutableStyleProperties& mutableProperties();

    void wrapperAdoptSelectorList(CSSSelectorList&& selectors) { m_selectorList = WTFMove(selectors); }

    Ref<StyleRulePage> copy() const { return adoptRef(*new StyleRulePage(*this)); }

private:
    explicit StyleRulePage(Ref<StyleProperties>&&, CSSSelectorList&&);
    StyleRulePage(const StyleRulePage&);
    
    Ref<StyleProperties> m_properties;
    CSSSelectorList m_selectorList;
};

class StyleRuleGroup : public StyleRuleBase {
public:
    const Vector<Ref<StyleRuleBase>>& childRules() const;

    void wrapperInsertRule(unsigned, Ref<StyleRuleBase>&&);
    void wrapperRemoveRule(unsigned);

    friend class CSSGroupingRule;
    friend class CSSStyleSheet;

protected:
    StyleRuleGroup(StyleRuleType, Vector<Ref<StyleRuleBase>>&&);
    StyleRuleGroup(const StyleRuleGroup&);
    
private:
    mutable Vector<Ref<StyleRuleBase>> m_childRules;
};

class StyleRuleMedia final : public StyleRuleGroup {
public:
    static Ref<StyleRuleMedia> create(MQ::MediaQueryList&&, Vector<Ref<StyleRuleBase>>&&);
    Ref<StyleRuleMedia> copy() const;

    const MQ::MediaQueryList& mediaQueries() const { return m_mediaQueries; }
    void setMediaQueries(MQ::MediaQueryList&& queries) { m_mediaQueries = WTFMove(queries); }

private:
    StyleRuleMedia(MQ::MediaQueryList&&, Vector<Ref<StyleRuleBase>>&&);
    StyleRuleMedia(const StyleRuleMedia&);

    MQ::MediaQueryList m_mediaQueries;
};

class StyleRuleSupports final : public StyleRuleGroup {
public:
    static Ref<StyleRuleSupports> create(const String& conditionText, bool conditionIsSupported, Vector<Ref<StyleRuleBase>>&&);
    Ref<StyleRuleSupports> copy() const { return adoptRef(*new StyleRuleSupports(*this)); }

    String conditionText() const { return m_conditionText; }
    bool conditionIsSupported() const { return m_conditionIsSupported; }

private:
    StyleRuleSupports(const String& conditionText, bool conditionIsSupported, Vector<Ref<StyleRuleBase>>&&);
    StyleRuleSupports(const StyleRuleSupports&) = default;

    String m_conditionText;
    bool m_conditionIsSupported;
};

class StyleRuleLayer final : public StyleRuleGroup {
public:
    static Ref<StyleRuleLayer> createStatement(Vector<CascadeLayerName>&&);
    static Ref<StyleRuleLayer> createBlock(CascadeLayerName&&, Vector<Ref<StyleRuleBase>>&&);
    Ref<StyleRuleLayer> copy() const { return adoptRef(*new StyleRuleLayer(*this)); }

    bool isStatement() const { return type() == StyleRuleType::LayerStatement; }

    auto& name() const { return std::get<CascadeLayerName>(m_nameVariant); }
    auto& nameList() const { return std::get<Vector<CascadeLayerName>>(m_nameVariant); }

private:
    StyleRuleLayer(Vector<CascadeLayerName>&&);
    StyleRuleLayer(CascadeLayerName&&, Vector<Ref<StyleRuleBase>>&&);
    StyleRuleLayer(const StyleRuleLayer&) = default;

    std::variant<CascadeLayerName, Vector<CascadeLayerName>> m_nameVariant;
};

class StyleRuleContainer final : public StyleRuleGroup {
public:
    static Ref<StyleRuleContainer> create(CQ::ContainerQuery&&, Vector<Ref<StyleRuleBase>>&&);
    Ref<StyleRuleContainer> copy() const { return adoptRef(*new StyleRuleContainer(*this)); }

    const CQ::ContainerQuery& containerQuery() const { return m_containerQuery; }

private:
    StyleRuleContainer(CQ::ContainerQuery&&, Vector<Ref<StyleRuleBase>>&&);
    StyleRuleContainer(const StyleRuleContainer&) = default;

    CQ::ContainerQuery m_containerQuery;
};

class StyleRuleProperty final : public StyleRuleBase {
public:
    struct Descriptor {
        AtomString name;
        String syntax { };
        std::optional<bool> inherits { };
        RefPtr<const CSSVariableData> initialValue { };
    };
    static Ref<StyleRuleProperty> create(Descriptor&&);
    Ref<StyleRuleProperty> copy() const { return adoptRef(*new StyleRuleProperty(*this)); }

    const Descriptor& descriptor() const { return m_descriptor; }

private:
    StyleRuleProperty(Descriptor&&);
    StyleRuleProperty(const StyleRuleProperty&) = default;

    Descriptor m_descriptor;
};

// This is only used by the CSS parser.
class StyleRuleCharset final : public StyleRuleBase {
public:
    static Ref<StyleRuleCharset> create() { return adoptRef(*new StyleRuleCharset); }
    Ref<StyleRuleCharset> copy() const { return adoptRef(*new StyleRuleCharset(*this)); }

private:
    StyleRuleCharset();
    StyleRuleCharset(const StyleRuleCharset&) = default;
};

class StyleRuleNamespace final : public StyleRuleBase {
public:
    static Ref<StyleRuleNamespace> create(const AtomString& prefix, const AtomString& uri);

    Ref<StyleRuleNamespace> copy() const { return adoptRef(*new StyleRuleNamespace(*this)); }

    AtomString prefix() const { return m_prefix; }
    AtomString uri() const { return m_uri; }

private:
    StyleRuleNamespace(const AtomString& prefix, const AtomString& uri);
    StyleRuleNamespace(const StyleRuleNamespace&) = default;

    AtomString m_prefix;
    AtomString m_uri;
};
    
inline StyleRuleBase::StyleRuleBase(StyleRuleType type, bool hasDocumentSecurityOrigin)
    : m_type(static_cast<unsigned>(type))
    , m_hasDocumentSecurityOrigin(hasDocumentSecurityOrigin)
{
}

inline StyleRuleBase::StyleRuleBase(const StyleRuleBase& o)
    : RefCounted()
    , m_type(o.m_type)
    , m_hasDocumentSecurityOrigin(o.m_hasDocumentSecurityOrigin)
{
}

inline void StyleRule::wrapperAdoptSelectorList(CSSSelectorList&& selectors)
{
    m_selectorList = WTFMove(selectors);
#if ENABLE(CSS_SELECTOR_JIT)
    m_compiledSelectors = nullptr;
#endif
}

inline void StyleRuleWithNesting::wrapperAdoptOriginalSelectorList(CSSSelectorList&& selectors)
{
    m_originalSelectorList = CSSSelectorList { selectors };
    StyleRule::wrapperAdoptSelectorList(WTFMove(selectors));
}

#if ENABLE(CSS_SELECTOR_JIT)

inline CompiledSelector& StyleRule::compiledSelectorForListIndex(unsigned index) const
{
    ASSERT(index < m_selectorList.listSize());

    if (!m_compiledSelectors) {
        auto listSize = m_selectorList.listSize();
        RELEASE_ASSERT_WITH_SECURITY_IMPLICATION(index < listSize);
        m_compiledSelectors = makeUniqueArray<CompiledSelector>(listSize);
    }
    return m_compiledSelectors[index];
}

#endif

} // namespace WebCore

SPECIALIZE_TYPE_TRAITS_BEGIN(WebCore::StyleRule)
    static bool isType(const WebCore::StyleRuleBase& rule) { return rule.isStyleRule(); }
SPECIALIZE_TYPE_TRAITS_END()

SPECIALIZE_TYPE_TRAITS_BEGIN(WebCore::StyleRuleWithNesting)
    static bool isType(const WebCore::StyleRuleBase& rule) { return rule.isStyleRuleWithNesting(); }
SPECIALIZE_TYPE_TRAITS_END()

SPECIALIZE_TYPE_TRAITS_BEGIN(WebCore::StyleRuleGroup)
    static bool isType(const WebCore::StyleRuleBase& rule) { return rule.isGroupRule(); }
SPECIALIZE_TYPE_TRAITS_END()

SPECIALIZE_TYPE_TRAITS_BEGIN(WebCore::StyleRuleFontFace)
    static bool isType(const WebCore::StyleRuleBase& rule) { return rule.isFontFaceRule(); }
SPECIALIZE_TYPE_TRAITS_END()

SPECIALIZE_TYPE_TRAITS_BEGIN(WebCore::StyleRuleFontFeatureValues)
    static bool isType(const WebCore::StyleRuleBase& rule) { return rule.isFontFeatureValuesRule(); }
SPECIALIZE_TYPE_TRAITS_END()

SPECIALIZE_TYPE_TRAITS_BEGIN(WebCore::StyleRuleFontFeatureValuesBlock)
    static bool isType(const WebCore::StyleRuleBase& rule) { return rule.isFontFeatureValuesBlockRule(); }
SPECIALIZE_TYPE_TRAITS_END()

SPECIALIZE_TYPE_TRAITS_BEGIN(WebCore::StyleRuleFontPaletteValues)
    static bool isType(const WebCore::StyleRuleBase& rule) { return rule.isFontPaletteValuesRule(); }
SPECIALIZE_TYPE_TRAITS_END()

SPECIALIZE_TYPE_TRAITS_BEGIN(WebCore::StyleRuleMedia)
    static bool isType(const WebCore::StyleRuleBase& rule) { return rule.isMediaRule(); }
SPECIALIZE_TYPE_TRAITS_END()

SPECIALIZE_TYPE_TRAITS_BEGIN(WebCore::StyleRulePage)
    static bool isType(const WebCore::StyleRuleBase& rule) { return rule.isPageRule(); }
SPECIALIZE_TYPE_TRAITS_END()

SPECIALIZE_TYPE_TRAITS_BEGIN(WebCore::StyleRuleSupports)
    static bool isType(const WebCore::StyleRuleBase& rule) { return rule.isSupportsRule(); }
SPECIALIZE_TYPE_TRAITS_END()

SPECIALIZE_TYPE_TRAITS_BEGIN(WebCore::StyleRuleNamespace)
    static bool isType(const WebCore::StyleRuleBase& rule) { return rule.isNamespaceRule(); }
SPECIALIZE_TYPE_TRAITS_END()

SPECIALIZE_TYPE_TRAITS_BEGIN(WebCore::StyleRuleKeyframe)
    static bool isType(const WebCore::StyleRuleBase& rule) { return rule.isKeyframeRule(); }
SPECIALIZE_TYPE_TRAITS_END()

SPECIALIZE_TYPE_TRAITS_BEGIN(WebCore::StyleRuleCharset)
    static bool isType(const WebCore::StyleRuleBase& rule) { return rule.isCharsetRule(); }
SPECIALIZE_TYPE_TRAITS_END()

SPECIALIZE_TYPE_TRAITS_BEGIN(WebCore::StyleRuleLayer)
    static bool isType(const WebCore::StyleRuleBase& rule) { return rule.isLayerRule(); }
SPECIALIZE_TYPE_TRAITS_END()

SPECIALIZE_TYPE_TRAITS_BEGIN(WebCore::StyleRuleContainer)
    static bool isType(const WebCore::StyleRuleBase& rule) { return rule.isContainerRule(); }
SPECIALIZE_TYPE_TRAITS_END()

SPECIALIZE_TYPE_TRAITS_BEGIN(WebCore::StyleRuleProperty)
    static bool isType(const WebCore::StyleRuleBase& rule) { return rule.isPropertyRule(); }
SPECIALIZE_TYPE_TRAITS_END()