jcs.org
Serenity Operating System
1/*
2 * Copyright (c) 2021, Andreas Kling <kling@serenityos.org>
3 *
4 * SPDX-License-Identifier: BSD-2-Clause
5 */
6
7#include <LibWeb/HTML/FormAssociatedElement.h>
8#include <LibWeb/HTML/HTMLButtonElement.h>
9#include <LibWeb/HTML/HTMLFieldSetElement.h>
10#include <LibWeb/HTML/HTMLFormElement.h>
11#include <LibWeb/HTML/HTMLInputElement.h>
12#include <LibWeb/HTML/HTMLLegendElement.h>
13#include <LibWeb/HTML/HTMLSelectElement.h>
14#include <LibWeb/HTML/HTMLTextAreaElement.h>
15#include <LibWeb/HTML/Parser/HTMLParser.h>
16
17namespace Web::HTML {
18
19void FormAssociatedElement::set_form(HTMLFormElement* form)
20{
21 if (m_form)
22 m_form->remove_associated_element({}, form_associated_element_to_html_element());
23 m_form = form;
24 if (m_form)
25 m_form->add_associated_element({}, form_associated_element_to_html_element());
26}
27
28bool FormAssociatedElement::enabled() const
29{
30 // https://html.spec.whatwg.org/multipage/form-control-infrastructure.html#concept-fe-disabled
31 auto const& html_element = const_cast<FormAssociatedElement&>(*this).form_associated_element_to_html_element();
32
33 // A form control is disabled if any of the following conditions are met:
34 // 1. The element is a button, input, select, textarea, or form-associated custom element, and the disabled attribute is specified on this element (regardless of its value).
35 // FIXME: This doesn't check for form-associated custom elements.
36 if ((is<HTMLButtonElement>(html_element) || is<HTMLInputElement>(html_element) || is<HTMLSelectElement>(html_element) || is<HTMLTextAreaElement>(html_element)) && html_element.has_attribute(HTML::AttributeNames::disabled))
37 return false;
38
39 // 2. The element is a descendant of a fieldset element whose disabled attribute is specified, and is not a descendant of that fieldset element's first legend element child, if any.
40 for (auto* fieldset_ancestor = html_element.first_ancestor_of_type<HTMLFieldSetElement>(); fieldset_ancestor; fieldset_ancestor = fieldset_ancestor->first_ancestor_of_type<HTMLFieldSetElement>()) {
41 if (fieldset_ancestor->has_attribute(HTML::AttributeNames::disabled)) {
42 auto* first_legend_element_child = fieldset_ancestor->first_child_of_type<HTMLLegendElement>();
43 if (!first_legend_element_child || !html_element.is_descendant_of(*first_legend_element_child))
44 return false;
45 }
46 }
47
48 return true;
49}
50
51void FormAssociatedElement::set_parser_inserted(Badge<HTMLParser>)
52{
53 m_parser_inserted = true;
54}
55
56// https://html.spec.whatwg.org/multipage/form-control-infrastructure.html#association-of-controls-and-forms:nodes-are-inserted
57void FormAssociatedElement::form_node_was_inserted()
58{
59 // 1. If the form-associated element's parser inserted flag is set, then return.
60 if (m_parser_inserted)
61 return;
62
63 // 2. Reset the form owner of the form-associated element.
64 reset_form_owner();
65}
66
67// https://html.spec.whatwg.org/multipage/form-control-infrastructure.html#association-of-controls-and-forms:nodes-are-removed
68void FormAssociatedElement::form_node_was_removed()
69{
70 // 1. If the form-associated element has a form owner and the form-associated element and its form owner are no longer in the same tree, then reset the form owner of the form-associated element.
71 if (m_form && &form_associated_element_to_html_element().root() != &m_form->root())
72 reset_form_owner();
73}
74
75// https://html.spec.whatwg.org/multipage/form-control-infrastructure.html#reset-the-form-owner
76void FormAssociatedElement::reset_form_owner()
77{
78 auto& html_element = form_associated_element_to_html_element();
79
80 // Although these aren't in the "reset form owner" algorithm, these here as they are triggers for this algorithm:
81 // FIXME: When a listed form-associated element's form attribute is set, changed, or removed, then the user agent must reset the form owner of that element.
82 // FIXME: When a listed form-associated element has a form attribute and the ID of any of the elements in the tree changes, then the user agent must reset the form owner of that form-associated element.
83 // FIXME: When a listed form-associated element has a form attribute and an element with an ID is inserted into or removed from the Document, then the user agent must reset the form owner of that form-associated element.
84
85 // 1. Unset element's parser inserted flag.
86 m_parser_inserted = false;
87
88 // 2. If all of the following conditions are true
89 // - element's form owner is not null
90 // - element is not listed or its form content attribute is not present
91 // - element's form owner is its nearest form element ancestor after the change to the ancestor chain
92 // then do nothing, and return.
93 if (m_form
94 && (!is_listed() || !html_element.has_attribute(HTML::AttributeNames::form))
95 && html_element.first_ancestor_of_type<HTMLFormElement>() == m_form.ptr()) {
96 return;
97 }
98
99 // 3. Set element's form owner to null.
100 set_form(nullptr);
101
102 // 4. If element is listed, has a form content attribute, and is connected, then:
103 if (is_listed() && html_element.has_attribute(HTML::AttributeNames::form) && html_element.is_connected()) {
104 // 1. If the first element in element's tree, in tree order, to have an ID that is identical to element's form content attribute's value, is a form element, then associate the element with that form element.
105 auto form_value = html_element.attribute(HTML::AttributeNames::form);
106 html_element.root().for_each_in_inclusive_subtree_of_type<HTMLFormElement>([this, &form_value](HTMLFormElement& form_element) {
107 if (form_element.attribute(HTML::AttributeNames::id) == form_value) {
108 set_form(&form_element);
109 return IterationDecision::Break;
110 }
111
112 return IterationDecision::Continue;
113 });
114 }
115
116 // 5. Otherwise, if element has an ancestor form element, then associate element with the nearest such ancestor form element.
117 else {
118 auto* form_ancestor = html_element.first_ancestor_of_type<HTMLFormElement>();
119 if (form_ancestor)
120 set_form(form_ancestor);
121 }
122}
123
124}