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Serenity Operating System
1/*
2 * Copyright (c) 2021-2022, Sam Atkins <atkinssj@serenityos.org>
3 *
4 * SPDX-License-Identifier: BSD-2-Clause
5 */
6
7#include <AK/TypeCasts.h>
8#include <LibWeb/Bindings/CSSRuleListPrototype.h>
9#include <LibWeb/Bindings/Intrinsics.h>
10#include <LibWeb/CSS/CSSImportRule.h>
11#include <LibWeb/CSS/CSSMediaRule.h>
12#include <LibWeb/CSS/CSSRule.h>
13#include <LibWeb/CSS/CSSRuleList.h>
14#include <LibWeb/CSS/CSSSupportsRule.h>
15#include <LibWeb/CSS/Parser/Parser.h>
16#include <LibWeb/HTML/Window.h>
17
18namespace Web::CSS {
19
20WebIDL::ExceptionOr<JS::NonnullGCPtr<CSSRuleList>> CSSRuleList::create(JS::Realm& realm, JS::MarkedVector<CSSRule*> const& rules)
21{
22 auto rule_list = MUST_OR_THROW_OOM(realm.heap().allocate<CSSRuleList>(realm, realm));
23 for (auto* rule : rules)
24 rule_list->m_rules.append(*rule);
25 return rule_list;
26}
27
28CSSRuleList::CSSRuleList(JS::Realm& realm)
29 : Bindings::LegacyPlatformObject(realm)
30{
31}
32
33WebIDL::ExceptionOr<JS::NonnullGCPtr<CSSRuleList>> CSSRuleList::create_empty(JS::Realm& realm)
34{
35 return MUST_OR_THROW_OOM(realm.heap().allocate<CSSRuleList>(realm, realm));
36}
37
38JS::ThrowCompletionOr<void> CSSRuleList::initialize(JS::Realm& realm)
39{
40 MUST_OR_THROW_OOM(Base::initialize(realm));
41 set_prototype(&Bindings::ensure_web_prototype<Bindings::CSSRuleListPrototype>(realm, "CSSRuleList"));
42
43 return {};
44}
45
46void CSSRuleList::visit_edges(Cell::Visitor& visitor)
47{
48 Base::visit_edges(visitor);
49 for (auto& rule : m_rules)
50 visitor.visit(&rule);
51}
52
53bool CSSRuleList::is_supported_property_index(u32 index) const
54{
55 // The object’s supported property indices are the numbers in the range zero to one less than the number of CSSRule objects represented by the collection.
56 // If there are no such CSSRule objects, then there are no supported property indices.
57 return index < m_rules.size();
58}
59
60// https://www.w3.org/TR/cssom/#insert-a-css-rule
61WebIDL::ExceptionOr<unsigned> CSSRuleList::insert_a_css_rule(Variant<StringView, CSSRule*> rule, u32 index)
62{
63 // 1. Set length to the number of items in list.
64 auto length = m_rules.size();
65
66 // 2. If index is greater than length, then throw an IndexSizeError exception.
67 if (index > length)
68 return WebIDL::IndexSizeError::create(realm(), "CSS rule index out of bounds.");
69
70 // 3. Set new rule to the results of performing parse a CSS rule on argument rule.
71 // NOTE: The insert-a-css-rule spec expects `rule` to be a string, but the CSSStyleSheet.insertRule()
72 // spec calls this algorithm with an already-parsed CSSRule. So, we use a Variant and skip step 3
73 // if that variant holds a CSSRule already.
74 CSSRule* new_rule = nullptr;
75 if (rule.has<StringView>()) {
76 new_rule = parse_css_rule(
77 CSS::Parser::ParsingContext { realm() },
78 rule.get<StringView>());
79 } else {
80 new_rule = rule.get<CSSRule*>();
81 }
82
83 // 4. If new rule is a syntax error, throw a SyntaxError exception.
84 if (!new_rule)
85 return WebIDL::SyntaxError::create(realm(), "Unable to parse CSS rule.");
86
87 // FIXME: 5. If new rule cannot be inserted into list at the zero-index position index due to constraints specified by CSS, then throw a HierarchyRequestError exception. [CSS21]
88
89 // FIXME: 6. If new rule is an @namespace at-rule, and list contains anything other than @import at-rules, and @namespace at-rules, throw an InvalidStateError exception.
90
91 // 7. Insert new rule into list at the zero-indexed position index.
92 m_rules.insert(index, *new_rule);
93
94 // 8. Return index.
95 return index;
96}
97
98// https://www.w3.org/TR/cssom/#remove-a-css-rule
99WebIDL::ExceptionOr<void> CSSRuleList::remove_a_css_rule(u32 index)
100{
101 // 1. Set length to the number of items in list.
102 auto length = m_rules.size();
103
104 // 2. If index is greater than or equal to length, then throw an IndexSizeError exception.
105 if (index >= length)
106 return WebIDL::IndexSizeError::create(realm(), "CSS rule index out of bounds.");
107
108 // 3. Set old rule to the indexth item in list.
109 CSSRule& old_rule = m_rules[index];
110
111 // FIXME: 4. If old rule is an @namespace at-rule, and list contains anything other than @import at-rules, and @namespace at-rules, throw an InvalidStateError exception.
112
113 // 5. Remove rule old rule from list at the zero-indexed position index.
114 m_rules.remove(index);
115
116 // 6. Set old rule’s parent CSS rule and parent CSS style sheet to null.
117 old_rule.set_parent_rule(nullptr);
118 old_rule.set_parent_style_sheet(nullptr);
119
120 return {};
121}
122
123void CSSRuleList::for_each_effective_style_rule(Function<void(CSSStyleRule const&)> const& callback) const
124{
125 for (auto const& rule : m_rules) {
126 switch (rule.type()) {
127 case CSSRule::Type::FontFace:
128 break;
129 case CSSRule::Type::Import: {
130 auto const& import_rule = static_cast<CSSImportRule const&>(rule);
131 if (import_rule.has_import_result() && import_rule.loaded_style_sheet())
132 import_rule.loaded_style_sheet()->for_each_effective_style_rule(callback);
133 break;
134 }
135 case CSSRule::Type::Media:
136 static_cast<CSSMediaRule const&>(rule).for_each_effective_style_rule(callback);
137 break;
138 case CSSRule::Type::Style:
139 callback(static_cast<CSSStyleRule const&>(rule));
140 break;
141 case CSSRule::Type::Supports:
142 static_cast<CSSSupportsRule const&>(rule).for_each_effective_style_rule(callback);
143 break;
144 }
145 }
146}
147
148bool CSSRuleList::evaluate_media_queries(HTML::Window const& window)
149{
150 bool any_media_queries_changed_match_state = false;
151
152 for (auto& rule : m_rules) {
153 switch (rule.type()) {
154 case CSSRule::Type::FontFace:
155 break;
156 case CSSRule::Type::Import: {
157 auto& import_rule = verify_cast<CSSImportRule>(rule);
158 if (import_rule.has_import_result() && import_rule.loaded_style_sheet() && import_rule.loaded_style_sheet()->evaluate_media_queries(window))
159 any_media_queries_changed_match_state = true;
160 break;
161 }
162 case CSSRule::Type::Media: {
163 auto& media_rule = verify_cast<CSSMediaRule>(rule);
164 bool did_match = media_rule.condition_matches();
165 bool now_matches = media_rule.evaluate(window);
166 if (did_match != now_matches)
167 any_media_queries_changed_match_state = true;
168 if (now_matches && media_rule.css_rules().evaluate_media_queries(window))
169 any_media_queries_changed_match_state = true;
170 break;
171 }
172 case CSSRule::Type::Style:
173 break;
174 case CSSRule::Type::Supports: {
175 auto& supports_rule = verify_cast<CSSSupportsRule>(rule);
176 if (supports_rule.condition_matches() && supports_rule.css_rules().evaluate_media_queries(window))
177 any_media_queries_changed_match_state = true;
178 break;
179 }
180 }
181 }
182
183 return any_media_queries_changed_match_state;
184}
185
186WebIDL::ExceptionOr<JS::Value> CSSRuleList::item_value(size_t index) const
187{
188 return item(index);
189}
190
191}