LibWeb: Partially implement MediaQuery class :^)

The main thing that's missing is the actual matching, but this is enough
to get started.

4 files changed, 233 insertions, 0 deletions

diff --git a/Userland/Libraries/LibWeb/CMakeLists.txt b/Userland/Libraries/LibWeb/CMakeLists.txt
index a2f0517ea0..911e28bd83 100644
--- a/Userland/Libraries/LibWeb/CMakeLists.txt
+++ b/Userland/Libraries/LibWeb/CMakeLists.txt
@@ -25,6 +25,7 @@ set(SOURCES
     CSS/ResolvedCSSStyleDeclaration.cpp
     CSS/DefaultStyleSheetSource.cpp
     CSS/Length.cpp
+    CSS/MediaQuery.cpp
     CSS/MediaQueryList.cpp
     CSS/Parser/Parser.cpp
     CSS/Parser/StyleRules.cpp
diff --git a/Userland/Libraries/LibWeb/CSS/MediaQuery.cpp b/Userland/Libraries/LibWeb/CSS/MediaQuery.cpp
new file mode 100644
index 0000000000..507d28a48a
--- /dev/null
+++ b/Userland/Libraries/LibWeb/CSS/MediaQuery.cpp
@@ -0,0 +1,113 @@
+/*
+ * Copyright (c) 2021, Sam Atkins <atkinssj@serenityos.org>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#include <LibWeb/CSS/MediaQuery.h>
+
+namespace Web::CSS {
+
+NonnullRefPtr<MediaQuery> MediaQuery::create_not_all()
+{
+    auto media_query = new MediaQuery;
+    media_query->m_negated = true;
+    media_query->m_media_type = MediaType::All;
+
+    return adopt_ref(*media_query);
+}
+
+String MediaQuery::MediaFeature::to_string() const
+{
+    switch (type) {
+    case Type::IsTrue:
+        return name;
+    case Type::ExactValue:
+        return String::formatted("{}:{}", name, value->to_string());
+    case Type::MinValue:
+        return String::formatted("min-{}:{}", name, value->to_string());
+    case Type::MaxValue:
+        return String::formatted("max-{}:{}", name, value->to_string());
+    }
+
+    VERIFY_NOT_REACHED();
+}
+
+String MediaQuery::MediaCondition::to_string() const
+{
+    StringBuilder builder;
+    builder.append('(');
+    switch (type) {
+    case Type::Single:
+        builder.append(feature.to_string());
+        break;
+    case Type::Not:
+        builder.append("not ");
+        builder.append(conditions.first().to_string());
+        break;
+    case Type::And:
+        builder.join(" and ", conditions);
+        break;
+    case Type::Or:
+        builder.join(" or ", conditions);
+        break;
+    }
+    builder.append(')');
+    return builder.to_string();
+}
+
+String MediaQuery::to_string() const
+{
+    StringBuilder builder;
+
+    if (m_negated)
+        builder.append("not ");
+
+    if (m_negated || m_media_type != MediaType::All || !m_media_condition) {
+        switch (m_media_type) {
+        case MediaType::All:
+            builder.append("all");
+            break;
+        case MediaType::Aural:
+            builder.append("aural");
+            break;
+        case MediaType::Braille:
+            builder.append("braille");
+            break;
+        case MediaType::Embossed:
+            builder.append("embossed");
+            break;
+        case MediaType::Handheld:
+            builder.append("handheld");
+            break;
+        case MediaType::Print:
+            builder.append("print");
+            break;
+        case MediaType::Projection:
+            builder.append("projection");
+            break;
+        case MediaType::Screen:
+            builder.append("screen");
+            break;
+        case MediaType::Speech:
+            builder.append("speech");
+            break;
+        case MediaType::TTY:
+            builder.append("tty");
+            break;
+        case MediaType::TV:
+            builder.append("tv");
+            break;
+        }
+        if (m_media_condition)
+            builder.append(" and ");
+    }
+
+    if (m_media_condition) {
+        builder.append(m_media_condition->to_string());
+    }
+
+    return builder.to_string();
+}
+
+}
diff --git a/Userland/Libraries/LibWeb/CSS/MediaQuery.h b/Userland/Libraries/LibWeb/CSS/MediaQuery.h
new file mode 100644
index 0000000000..97775333c3
--- /dev/null
+++ b/Userland/Libraries/LibWeb/CSS/MediaQuery.h
@@ -0,0 +1,117 @@
+/*
+ * Copyright (c) 2021, Sam Atkins <atkinssj@serenityos.org>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#pragma once
+
+#include <AK/FlyString.h>
+#include <AK/NonnullOwnPtrVector.h>
+#include <AK/NonnullRefPtr.h>
+#include <AK/Optional.h>
+#include <AK/OwnPtr.h>
+#include <AK/RefCounted.h>
+#include <LibWeb/CSS/StyleValue.h>
+
+namespace Web::CSS {
+
+class MediaQuery : public RefCounted<MediaQuery> {
+    friend class Parser;
+
+public:
+    ~MediaQuery() { }
+
+    // https://www.w3.org/TR/mediaqueries-4/#media-types
+    enum class MediaType {
+        All,
+        Print,
+        Screen,
+
+        // Deprecated, must never match:
+        TTY,
+        TV,
+        Projection,
+        Handheld,
+        Braille,
+        Embossed,
+        Aural,
+        Speech,
+    };
+
+    // https://www.w3.org/TR/mediaqueries-4/#mq-features
+    struct MediaFeature {
+        // FIXME: Implement range syntax: https://www.w3.org/TR/mediaqueries-4/#mq-ranges
+        enum class Type {
+            IsTrue,
+            ExactValue,
+            MinValue,
+            MaxValue,
+        };
+
+        Type type;
+        FlyString name;
+        RefPtr<StyleValue> value { nullptr };
+
+        String to_string() const;
+    };
+
+    // https://www.w3.org/TR/mediaqueries-4/#media-conditions
+    struct MediaCondition {
+        enum class Type {
+            Single,
+            And,
+            Or,
+            Not,
+        };
+
+        Type type;
+        MediaFeature feature;
+        NonnullOwnPtrVector<MediaCondition> conditions;
+
+        String to_string() const;
+    };
+
+    static NonnullRefPtr<MediaQuery> create_not_all();
+    static NonnullRefPtr<MediaQuery> create() { return adopt_ref(*new MediaQuery); }
+
+    String to_string() const;
+
+private:
+    MediaQuery() { }
+
+    // https://www.w3.org/TR/mediaqueries-4/#mq-not
+    bool m_negated { false };
+    MediaType m_media_type { MediaType::All };
+    OwnPtr<MediaCondition> m_media_condition { nullptr };
+};
+
+}
+
+namespace AK {
+
+template<>
+struct Formatter<Web::CSS::MediaQuery::MediaFeature> : Formatter<StringView> {
+    void format(FormatBuilder& builder, Web::CSS::MediaQuery::MediaFeature const& media_feature)
+    {
+        Formatter<StringView>::format(builder, media_feature.to_string());
+    }
+};
+
+template<>
+struct Formatter<Web::CSS::MediaQuery::MediaCondition> : Formatter<StringView> {
+    void format(FormatBuilder& builder, Web::CSS::MediaQuery::MediaCondition const& media_condition)
+    {
+        Formatter<StringView>::format(builder, media_condition.to_string());
+    }
+};
+
+template<>
+struct Formatter<Web::CSS::MediaQuery> : Formatter<StringView> {
+    void format(FormatBuilder& builder, Web::CSS::MediaQuery const& media_query)
+    {
+        Formatter<StringView>::format(builder, media_query.to_string());
+    }
+};
+
+}
diff --git a/Userland/Libraries/LibWeb/Forward.h b/Userland/Libraries/LibWeb/Forward.h
index 66f27a3e00..a456b8bae0 100644
--- a/Userland/Libraries/LibWeb/Forward.h
+++ b/Userland/Libraries/LibWeb/Forward.h
@@ -26,6 +26,8 @@ class CSSStyleRule;
 class CSSStyleSheet;
 class ElementInlineCSSStyleDeclaration;
 class Length;
+class MediaQuery;
+class MediaQueryList;
 class PropertyOwningCSSStyleDeclaration;
 class Screen;
 class Selector;