LibWeb: Create base class CSSRule for all CSS rules

This is a foundation for handling other ("at") CSS rules.

12 files changed, 147 insertions, 17 deletions

diff --git a/Userland/Libraries/LibWeb/CMakeLists.txt b/Userland/Libraries/LibWeb/CMakeLists.txt
index 563f3f743e..61ed208ca5 100644
--- a/Userland/Libraries/LibWeb/CMakeLists.txt
+++ b/Userland/Libraries/LibWeb/CMakeLists.txt
@@ -9,6 +9,7 @@ set(SOURCES
     Bindings/ScriptExecutionContext.cpp
     Bindings/WindowObject.cpp
     Bindings/Wrappable.cpp
+    CSS/CSSRule.cpp
     CSS/DefaultStyleSheetSource.cpp
     CSS/Length.cpp
     CSS/Parser/CSSParser.cpp
diff --git a/Userland/Libraries/LibWeb/CSS/CSSRule.cpp b/Userland/Libraries/LibWeb/CSS/CSSRule.cpp
new file mode 100644
index 0000000000..1f4790293c
--- /dev/null
+++ b/Userland/Libraries/LibWeb/CSS/CSSRule.cpp
@@ -0,0 +1,35 @@
+/*
+ * Copyright (c) 2021, the SerenityOS developers.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice, this
+ *    list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ *
+ * 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 HOLDER 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.
+ */
+
+#include <LibWeb/CSS/CSSRule.h>
+
+namespace Web::CSS {
+
+CSSRule::~CSSRule()
+{
+}
+
+}
diff --git a/Userland/Libraries/LibWeb/CSS/CSSRule.h b/Userland/Libraries/LibWeb/CSS/CSSRule.h
new file mode 100644
index 0000000000..de2a365252
--- /dev/null
+++ b/Userland/Libraries/LibWeb/CSS/CSSRule.h
@@ -0,0 +1,53 @@
+/*
+ * Copyright (c) 2021, the SerenityOS developers.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice, this
+ *    list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ *
+ * 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 HOLDER 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.
+ */
+
+#pragma once
+
+#include <AK/RefCounted.h>
+#include <AK/String.h>
+#include <LibWeb/CSS/Selector.h>
+#include <LibWeb/CSS/StyleDeclaration.h>
+
+namespace Web::CSS {
+
+class CSSRule : public RefCounted<CSSRule> {
+public:
+    virtual ~CSSRule();
+
+    enum class Type : u32 {
+        Style,
+        Import,
+        Media,
+        __Count,
+    };
+
+    virtual StringView class_name() const = 0;
+    virtual Type type() const = 0;
+
+private:
+};
+
+}
diff --git a/Userland/Libraries/LibWeb/CSS/Parser/CSSParser.cpp b/Userland/Libraries/LibWeb/CSS/Parser/CSSParser.cpp
index 87fcde8d6e..b83b21c238 100644
--- a/Userland/Libraries/LibWeb/CSS/Parser/CSSParser.cpp
+++ b/Userland/Libraries/LibWeb/CSS/Parser/CSSParser.cpp
@@ -25,8 +25,10 @@
  */
 
 #include <AK/HashMap.h>
+#include <LibWeb/CSS/CSSRule.h>
 #include <LibWeb/CSS/Parser/CSSParser.h>
 #include <LibWeb/CSS/PropertyID.h>
+#include <LibWeb/CSS/StyleRule.h>
 #include <LibWeb/CSS/StyleSheet.h>
 #include <LibWeb/DOM/Document.h>
 #include <ctype.h>
@@ -853,7 +855,7 @@ public:
 private:
     CSS::ParsingContext m_context;
 
-    NonnullRefPtrVector<CSS::StyleRule> rules;
+    NonnullRefPtrVector<CSS::CSSRule> rules;
 
     struct CurrentRule {
         Vector<CSS::Selector> selectors;
diff --git a/Userland/Libraries/LibWeb/CSS/StyleInvalidator.cpp b/Userland/Libraries/LibWeb/CSS/StyleInvalidator.cpp
index bf5f15c332..d5d7b14ca8 100644
--- a/Userland/Libraries/LibWeb/CSS/StyleInvalidator.cpp
+++ b/Userland/Libraries/LibWeb/CSS/StyleInvalidator.cpp
@@ -25,6 +25,7 @@
  */
 
 #include <LibWeb/CSS/StyleInvalidator.h>
+#include <LibWeb/CSS/StyleRule.h>
 #include <LibWeb/DOM/Document.h>
 #include <LibWeb/DOM/Element.h>
 
diff --git a/Userland/Libraries/LibWeb/CSS/StyleResolver.cpp b/Userland/Libraries/LibWeb/CSS/StyleResolver.cpp
index 2ced865baa..544e8cc646 100644
--- a/Userland/Libraries/LibWeb/CSS/StyleResolver.cpp
+++ b/Userland/Libraries/LibWeb/CSS/StyleResolver.cpp
@@ -1,5 +1,6 @@
 /*
  * Copyright (c) 2018-2020, Andreas Kling <kling@serenityos.org>
+ * Copyright (c) 2021, the SerenityOS developers.
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
@@ -28,6 +29,7 @@
 #include <LibWeb/CSS/Parser/CSSParser.h>
 #include <LibWeb/CSS/SelectorEngine.h>
 #include <LibWeb/CSS/StyleResolver.h>
+#include <LibWeb/CSS/StyleRule.h>
 #include <LibWeb/CSS/StyleSheet.h>
 #include <LibWeb/DOM/Document.h>
 #include <LibWeb/DOM/Element.h>
@@ -86,7 +88,7 @@ Vector<MatchingRule> StyleResolver::collect_matching_rules(const DOM::Element& e
     size_t style_sheet_index = 0;
     for_each_stylesheet([&](auto& sheet) {
         size_t rule_index = 0;
-        for (auto& rule : sheet.rules()) {
+        sheet.for_each_effective_style_rule([&](auto& rule) {
             size_t selector_index = 0;
             for (auto& selector : rule.selectors()) {
                 if (SelectorEngine::matches(selector, element)) {
@@ -96,7 +98,7 @@ Vector<MatchingRule> StyleResolver::collect_matching_rules(const DOM::Element& e
                 ++selector_index;
             }
             ++rule_index;
-        }
+        });
         ++style_sheet_index;
     });
 
diff --git a/Userland/Libraries/LibWeb/CSS/StyleRule.h b/Userland/Libraries/LibWeb/CSS/StyleRule.h
index d668c5b42b..8e2d3acf44 100644
--- a/Userland/Libraries/LibWeb/CSS/StyleRule.h
+++ b/Userland/Libraries/LibWeb/CSS/StyleRule.h
@@ -1,5 +1,6 @@
 /*
  * Copyright (c) 2018-2020, Andreas Kling <kling@serenityos.org>
+ * Copyright (c) 2021, the SerenityOS developers.
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
@@ -27,12 +28,13 @@
 #pragma once
 
 #include <AK/NonnullRefPtrVector.h>
+#include <LibWeb/CSS/CSSRule.h>
 #include <LibWeb/CSS/Selector.h>
 #include <LibWeb/CSS/StyleDeclaration.h>
 
 namespace Web::CSS {
 
-class StyleRule : public RefCounted<StyleRule> {
+class StyleRule : public CSSRule {
     AK_MAKE_NONCOPYABLE(StyleRule);
     AK_MAKE_NONMOVABLE(StyleRule);
 
@@ -47,6 +49,9 @@ public:
     const Vector<Selector>& selectors() const { return m_selectors; }
     const StyleDeclaration& declaration() const { return m_declaration; }
 
+    virtual StringView class_name() const { return "StyleRule"; };
+    virtual Type type() const { return Type::Style; };
+
 private:
     StyleRule(Vector<Selector>&&, NonnullRefPtr<StyleDeclaration>&&);
 
diff --git a/Userland/Libraries/LibWeb/CSS/StyleSheet.cpp b/Userland/Libraries/LibWeb/CSS/StyleSheet.cpp
index d4c37ba53e..fd664327b7 100644
--- a/Userland/Libraries/LibWeb/CSS/StyleSheet.cpp
+++ b/Userland/Libraries/LibWeb/CSS/StyleSheet.cpp
@@ -1,5 +1,6 @@
 /*
  * Copyright (c) 2018-2020, Andreas Kling <kling@serenityos.org>
+ * Copyright (c) 2021, the SerenityOS developers.
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
@@ -28,7 +29,7 @@
 
 namespace Web::CSS {
 
-StyleSheet::StyleSheet(NonnullRefPtrVector<StyleRule>&& rules)
+StyleSheet::StyleSheet(NonnullRefPtrVector<CSSRule>&& rules)
     : m_rules(move(rules))
 {
 }
diff --git a/Userland/Libraries/LibWeb/CSS/StyleSheet.h b/Userland/Libraries/LibWeb/CSS/StyleSheet.h
index 9e3695e03d..146a6a172d 100644
--- a/Userland/Libraries/LibWeb/CSS/StyleSheet.h
+++ b/Userland/Libraries/LibWeb/CSS/StyleSheet.h
@@ -1,5 +1,6 @@
 /*
  * Copyright (c) 2018-2020, Andreas Kling <kling@serenityos.org>
+ * Copyright (c) 2021, the SerenityOS developers.
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
@@ -27,26 +28,37 @@
 #pragma once
 
 #include <AK/NonnullRefPtrVector.h>
-#include <LibWeb/CSS/StyleRule.h>
+#include <AK/TypeCasts.h>
+#include <LibWeb/CSS/CSSRule.h>
+#include <LibWeb/Loader/Resource.h>
 
 namespace Web::CSS {
 
 class StyleSheet : public RefCounted<StyleSheet> {
 public:
-    static NonnullRefPtr<StyleSheet> create(NonnullRefPtrVector<StyleRule>&& rules)
+    static NonnullRefPtr<StyleSheet> create(NonnullRefPtrVector<CSSRule>&& rules)
     {
         return adopt(*new StyleSheet(move(rules)));
     }
 
     ~StyleSheet();
 
-    const NonnullRefPtrVector<StyleRule>& rules() const { return m_rules; }
-    NonnullRefPtrVector<StyleRule>& rules() { return m_rules; }
+    const NonnullRefPtrVector<CSSRule>& rules() const { return m_rules; }
+    NonnullRefPtrVector<CSSRule>& rules() { return m_rules; }
+
+    template<typename Callback>
+    void for_each_effective_style_rule(Callback callback) const
+    {
+        for (auto& rule : m_rules)
+            if (rule.type() == CSSRule::Type::Style) {
+                callback(downcast<StyleRule>(rule));
+            }
+    }
 
 private:
-    explicit StyleSheet(NonnullRefPtrVector<StyleRule>&&);
+    explicit StyleSheet(NonnullRefPtrVector<CSSRule>&&);
 
-    NonnullRefPtrVector<StyleRule> m_rules;
+    NonnullRefPtrVector<CSSRule> m_rules;
 };
 
 }
diff --git a/Userland/Libraries/LibWeb/Dump.cpp b/Userland/Libraries/LibWeb/Dump.cpp
index cb7a8bc62e..2ce412a23a 100644
--- a/Userland/Libraries/LibWeb/Dump.cpp
+++ b/Userland/Libraries/LibWeb/Dump.cpp
@@ -1,5 +1,6 @@
 /*
  * Copyright (c) 2018-2021, Andreas Kling <kling@serenityos.org>
+ * Copyright (c) 2021, the SerenityOS developers.
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
@@ -27,7 +28,9 @@
 #include <AK/QuickSort.h>
 #include <AK/StringBuilder.h>
 #include <AK/Utf8View.h>
+#include <LibWeb/CSS/CSSRule.h>
 #include <LibWeb/CSS/PropertyID.h>
+#include <LibWeb/CSS/StyleRule.h>
 #include <LibWeb/CSS/StyleSheet.h>
 #include <LibWeb/DOM/Comment.h>
 #include <LibWeb/DOM/Document.h>
@@ -389,16 +392,27 @@ void dump_selector(StringBuilder& builder, const CSS::Selector& selector)
     }
 }
 
-void dump_rule(const CSS::StyleRule& rule)
+void dump_rule(const CSS::CSSRule& rule)
 {
     StringBuilder builder;
     dump_rule(builder, rule);
     dbgln("{}", builder.string_view());
 }
 
-void dump_rule(StringBuilder& builder, const CSS::StyleRule& rule)
+void dump_rule(StringBuilder& builder, const CSS::CSSRule& rule)
+{
+    builder.appendff("{}:\n", rule.class_name());
+    switch (rule.type()) {
+    case CSS::CSSRule::Type::Style:
+        dump_style_rule(builder, downcast<const CSS::StyleRule>(rule));
+        break;
+    default:
+        VERIFY_NOT_REACHED();
+    }
+}
+
+void dump_style_rule(StringBuilder& builder, const CSS::StyleRule& rule)
 {
-    builder.append("Rule:\n");
     for (auto& selector : rule.selectors()) {
         dump_selector(builder, selector);
     }
@@ -417,7 +431,7 @@ void dump_sheet(const CSS::StyleSheet& sheet)
 
 void dump_sheet(StringBuilder& builder, const CSS::StyleSheet& sheet)
 {
-    builder.appendff("StyleSheet{{{}}}: {} rule(s)", &sheet, sheet.rules().size());
+    builder.appendff("StyleSheet{{{}}}: {} rule(s)\n", &sheet, sheet.rules().size());
 
     for (auto& rule : sheet.rules()) {
         dump_rule(builder, rule);
diff --git a/Userland/Libraries/LibWeb/Dump.h b/Userland/Libraries/LibWeb/Dump.h
index aabbab6ee0..78ba4a46bd 100644
--- a/Userland/Libraries/LibWeb/Dump.h
+++ b/Userland/Libraries/LibWeb/Dump.h
@@ -1,5 +1,6 @@
 /*
  * Copyright (c) 2018-2021, Andreas Kling <kling@serenityos.org>
+ * Copyright (c) 2021, the SerenityOS developers.
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
@@ -37,8 +38,9 @@ void dump_tree(StringBuilder&, const Layout::Node&, bool show_box_model = false,
 void dump_tree(const Layout::Node&, bool show_box_model = false, bool show_specified_style = false);
 void dump_sheet(StringBuilder&, const CSS::StyleSheet&);
 void dump_sheet(const CSS::StyleSheet&);
-void dump_rule(StringBuilder&, const CSS::StyleRule&);
-void dump_rule(const CSS::StyleRule&);
+void dump_rule(StringBuilder&, const CSS::CSSRule&);
+void dump_rule(const CSS::CSSRule&);
+void dump_style_rule(StringBuilder&, const CSS::StyleRule&);
 void dump_selector(StringBuilder&, const CSS::Selector&);
 void dump_selector(const CSS::Selector&);
 
diff --git a/Userland/Libraries/LibWeb/Forward.h b/Userland/Libraries/LibWeb/Forward.h
index cf5664944a..f7a9b71fc0 100644
--- a/Userland/Libraries/LibWeb/Forward.h
+++ b/Userland/Libraries/LibWeb/Forward.h
@@ -1,5 +1,6 @@
 /*
  * Copyright (c) 2020-2021, Andreas Kling <kling@serenityos.org>
+ * Copyright (c) 2021, the SerenityOS developers.
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
@@ -27,6 +28,7 @@
 #pragma once
 
 namespace Web::CSS {
+class CSSRule;
 class Length;
 class Selector;
 class StyleDeclaration;