summaryrefslogtreecommitdiff
path: root/Userland/Libraries/LibWeb/DOM/HTMLCollection.cpp
blob: 550e946e6ea2479c47389b0adedb6b11821dfbba (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
/*
 * Copyright (c) 2021-2022, Andreas Kling <kling@serenityos.org>
 * Copyright (c) 2021, Luke Wilde <lukew@serenityos.org>
 *
 * SPDX-License-Identifier: BSD-2-Clause
 */

#include <LibWeb/Bindings/Intrinsics.h>
#include <LibWeb/DOM/Element.h>
#include <LibWeb/DOM/HTMLCollection.h>
#include <LibWeb/DOM/ParentNode.h>
#include <LibWeb/Namespace.h>

namespace Web::DOM {

JS::NonnullGCPtr<HTMLCollection> HTMLCollection::create(ParentNode& root, Function<bool(Element const&)> filter)
{
    return *root.heap().allocate<HTMLCollection>(root.realm(), root, move(filter));
}

HTMLCollection::HTMLCollection(ParentNode& root, Function<bool(Element const&)> filter)
    : LegacyPlatformObject(Bindings::cached_web_prototype(root.realm(), "HTMLCollection"))
    , m_root(root)
    , m_filter(move(filter))
{
}

HTMLCollection::~HTMLCollection() = default;

void HTMLCollection::visit_edges(Cell::Visitor& visitor)
{
    Base::visit_edges(visitor);
    visitor.visit(m_root.ptr());
}

JS::MarkedVector<Element*> HTMLCollection::collect_matching_elements() const
{
    JS::MarkedVector<Element*> elements(m_root->heap());
    m_root->for_each_in_inclusive_subtree_of_type<Element>([&](auto& element) {
        if (m_filter(element))
            elements.append(const_cast<Element*>(&element));
        return IterationDecision::Continue;
    });
    return elements;
}

// https://dom.spec.whatwg.org/#dom-htmlcollection-length
size_t HTMLCollection::length()
{
    // The length getter steps are to return the number of nodes represented by the collection.
    return collect_matching_elements().size();
}

// https://dom.spec.whatwg.org/#dom-htmlcollection-item
Element* HTMLCollection::item(size_t index) const
{
    // The item(index) method steps are to return the indexth element in the collection. If there is no indexth element in the collection, then the method must return null.
    auto elements = collect_matching_elements();
    if (index >= elements.size())
        return nullptr;
    return elements[index];
}

// https://dom.spec.whatwg.org/#dom-htmlcollection-nameditem-key
Element* HTMLCollection::named_item(FlyString const& name) const
{
    // 1. If key is the empty string, return null.
    if (name.is_empty())
        return nullptr;
    auto elements = collect_matching_elements();
    // 2. Return the first element in the collection for which at least one of the following is true:
    //      - it has an ID which is key;
    if (auto it = elements.find_if([&](auto& entry) { return entry->attribute(HTML::AttributeNames::id) == name; }); it != elements.end())
        return *it;
    //      - it is in the HTML namespace and has a name attribute whose value is key;
    if (auto it = elements.find_if([&](auto& entry) { return entry->namespace_() == Namespace::HTML && entry->name() == name; }); it != elements.end())
        return *it;
    //    or null if there is no such element.
    return nullptr;
}

// https://dom.spec.whatwg.org/#ref-for-dfn-supported-property-names
Vector<DeprecatedString> HTMLCollection::supported_property_names() const
{
    // 1. Let result be an empty list.
    Vector<DeprecatedString> result;

    // 2. For each element represented by the collection, in tree order:
    auto elements = collect_matching_elements();

    for (auto& element : elements) {
        // 1. If element has an ID which is not in result, append element’s ID to result.
        if (element->has_attribute(HTML::AttributeNames::id)) {
            auto id = element->attribute(HTML::AttributeNames::id);

            if (!result.contains_slow(id))
                result.append(id);
        }

        // 2. If element is in the HTML namespace and has a name attribute whose value is neither the empty string nor is in result, append element’s name attribute value to result.
        if (element->namespace_() == Namespace::HTML && element->has_attribute(HTML::AttributeNames::name)) {
            auto name = element->attribute(HTML::AttributeNames::name);

            if (!name.is_empty() && !result.contains_slow(name))
                result.append(name);
        }
    }

    // 3. Return result.
    return result;
}

// https://dom.spec.whatwg.org/#ref-for-dfn-supported-property-indices%E2%91%A1
bool HTMLCollection::is_supported_property_index(u32 index) const
{
    // The object’s supported property indices are the numbers in the range zero to one less than the number of elements represented by the collection.
    // If there are no such elements, then there are no supported property indices.
    auto elements = collect_matching_elements();
    if (elements.is_empty())
        return false;

    return index < elements.size();
}

JS::Value HTMLCollection::item_value(size_t index) const
{
    auto* element = item(index);
    if (!element)
        return JS::js_undefined();
    return const_cast<Element*>(element);
}

JS::Value HTMLCollection::named_item_value(FlyString const& index) const
{
    auto* element = named_item(index);
    if (!element)
        return JS::js_undefined();
    return const_cast<Element*>(element);
}
}