Everywhere: Hoist the Libraries folder to the top-level

Author: https://github.com/trflynn89
Commit: 93712b24bf
Pull-request: https://github.com/LadybirdBrowser/ladybird/pull/2256
Reviewed-by: https://github.com/sideshowbarker

Libraries/LibWeb/HTML/HTMLMetaElement.cpp

@@ -0,0 +1,163 @@
+/*
+ * Copyright (c) 2020, the SerenityOS developers.
+ * Copyright (c) 2023, Luke Wilde <lukew@serenityos.org>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#include <AK/GenericLexer.h>
+#include <LibWeb/Bindings/HTMLMetaElementPrototype.h>
+#include <LibWeb/Bindings/Intrinsics.h>
+#include <LibWeb/CSS/Parser/Parser.h>
+#include <LibWeb/CSS/Parser/ParsingContext.h>
+#include <LibWeb/CSS/PropertyID.h>
+#include <LibWeb/CSS/StyleValues/CSSColorValue.h>
+#include <LibWeb/DOM/Document.h>
+#include <LibWeb/HTML/HTMLMetaElement.h>
+#include <LibWeb/Infra/CharacterTypes.h>
+#include <LibWeb/Page/Page.h>
+
+namespace Web::HTML {
+
+JS_DEFINE_ALLOCATOR(HTMLMetaElement);
+
+HTMLMetaElement::HTMLMetaElement(DOM::Document& document, DOM::QualifiedName qualified_name)
+    : HTMLElement(document, move(qualified_name))
+{
+}
+
+HTMLMetaElement::~HTMLMetaElement() = default;
+
+void HTMLMetaElement::initialize(JS::Realm& realm)
+{
+    Base::initialize(realm);
+    WEB_SET_PROTOTYPE_FOR_INTERFACE(HTMLMetaElement);
+}
+
+Optional<HTMLMetaElement::HttpEquivAttributeState> HTMLMetaElement::http_equiv_state() const
+{
+    auto value = get_attribute_value(HTML::AttributeNames::http_equiv);
+
+#define __ENUMERATE_HTML_META_HTTP_EQUIV_ATTRIBUTE(keyword, state) \
+    if (value.equals_ignoring_ascii_case(keyword##sv))             \
+        return HTMLMetaElement::HttpEquivAttributeState::state;
+    ENUMERATE_HTML_META_HTTP_EQUIV_ATTRIBUTES
+#undef __ENUMERATE_HTML_META_HTTP_EQUIV_ATTRIBUTE
+
+    return OptionalNone {};
+}
+
+void HTMLMetaElement::inserted()
+{
+    Base::inserted();
+
+    // https://html.spec.whatwg.org/multipage/semantics.html#meta-theme-color
+    // 1. To obtain a page's theme color, user agents must run the following steps:
+    //     * The element is in a document tree
+    //     * The element has a name attribute, whose value is an ASCII case-insensitive match for theme-color
+    //     * The element has a content attribute
+    auto content = attribute(AttributeNames::content);
+    if (name().has_value() && name()->equals_ignoring_ascii_case("theme-color"sv) && content.has_value()) {
+        auto context = CSS::Parser::ParsingContext { document() };
+
+        // 2. For each element in candidate elements:
+
+        // 1. If element has a media attribute and the value of element's media attribute does not match the environment, then continue.
+        auto media = attribute(AttributeNames::media);
+        if (media.has_value()) {
+            auto query = parse_media_query(context, media.value());
+            if (document().window() && !query->evaluate(*document().window()))
+                return;
+        }
+
+        // 2. Let value be the result of stripping leading and trailing ASCII whitespace from the value of element's content attribute.
+        auto value = content->bytes_as_string_view().trim(Infra::ASCII_WHITESPACE);
+
+        // 3. Let color be the result of parsing value.
+        auto css_value = parse_css_value(context, value, CSS::PropertyID::Color);
+        if (css_value.is_null() || !css_value->is_color())
+            return;
+        auto color = css_value->to_color({}); // TODO: Pass a layout node?
+
+        // 4. If color is not failure, then return color.
+        document().page().client().page_did_change_theme_color(color);
+        return;
+    }
+
+    // https://html.spec.whatwg.org/multipage/semantics.html#pragma-directives
+    // When a meta element is inserted into the document, if its http-equiv attribute is present and represents one of
+    // the above states, then the user agent must run the algorithm appropriate for that state, as described in the
+    // following list:
+    auto http_equiv = http_equiv_state();
+    if (http_equiv.has_value()) {
+        switch (http_equiv.value()) {
+        case HttpEquivAttributeState::EncodingDeclaration:
+            // https://html.spec.whatwg.org/multipage/semantics.html#attr-meta-http-equiv-content-type
+            // The Encoding declaration state is just an alternative form of setting the charset attribute: it is a character encoding declaration.
+            // This state's user agent requirements are all handled by the parsing section of the specification.
+            break;
+        case HttpEquivAttributeState::Refresh: {
+            // https://html.spec.whatwg.org/multipage/semantics.html#attr-meta-http-equiv-refresh
+            // 1. If the meta element has no content attribute, or if that attribute's value is the empty string, then return.
+            // 2. Let input be the value of the element's content attribute.
+            if (!has_attribute(AttributeNames::content))
+                break;
+
+            auto input = get_attribute_value(AttributeNames::content);
+            if (input.is_empty())
+                break;
+
+            // 3. Run the shared declarative refresh steps with the meta element's node document, input, and the meta element.
+            document().shared_declarative_refresh_steps(input, this);
+            break;
+        }
+        case HttpEquivAttributeState::SetCookie:
+            // https://html.spec.whatwg.org/multipage/semantics.html#attr-meta-http-equiv-set-cookie
+            // This pragma is non-conforming and has no effect.
+            // User agents are required to ignore this pragma.
+            break;
+        case HttpEquivAttributeState::XUACompatible:
+            // https://html.spec.whatwg.org/multipage/semantics.html#attr-meta-http-equiv-x-ua-compatible
+            // In practice, this pragma encourages Internet Explorer to more closely follow the specifications.
+            // For meta elements with an http-equiv attribute in the X-UA-Compatible state, the content attribute must have a value that is an ASCII case-insensitive match for the string "IE=edge".
+            // User agents are required to ignore this pragma.
+            break;
+        case HttpEquivAttributeState::ContentLanguage: {
+            // https://html.spec.whatwg.org/multipage/semantics.html#attr-meta-http-equiv-content-language
+            // 1. If the meta element has no content attribute, then return.
+            if (!has_attribute(AttributeNames::content))
+                break;
+
+            // 2. If the element's content attribute contains a U+002C COMMA character (,) then return.
+            auto content = get_attribute_value(AttributeNames::content);
+            if (content.contains(","sv))
+                break;
+
+            // 3. Let input be the value of the element's content attribute.
+            // 4. Let position point at the first character of input.
+            GenericLexer lexer { content };
+
+            // 5. Skip ASCII whitespace within input given position.
+            lexer.ignore_while(Web::Infra::is_ascii_whitespace);
+
+            // 6. Collect a sequence of code points that are not ASCII whitespace from input given position.
+            // 7. Let candidate be the string that resulted from the previous step.
+            auto candidate = lexer.consume_until(Web::Infra::is_ascii_whitespace);
+
+            // 8. If candidate is the empty string, return.
+            if (candidate.is_empty())
+                break;
+
+            // 9. Set the pragma-set default language to candidate.
+            auto language = String::from_utf8_without_validation(candidate.bytes());
+            document().set_pragma_set_default_language(language);
+            break;
+        }
+        default:
+            dbgln("FIXME: Implement '{}' http-equiv state", get_attribute_value(AttributeNames::http_equiv));
+            break;
+        }
+    }
+}
+
+}