MediaWiki 1.30.2

[autoinstallsdev/mediawiki.git] / vendor / oojs / oojs-ui / php / mixins / TabIndexedElement.php

diff --git a/vendor/oojs/oojs-ui/php/mixins/TabIndexedElement.php b/vendor/oojs/oojs-ui/php/mixins/TabIndexedElement.php
new file mode 100644 (file)
index 0000000..398281e
--- /dev/null
+++ b/vendor/oojs/oojs-ui/php/mixins/TabIndexedElement.php
@@ -0,0 +1,132 @@
+<?php
+
+namespace OOUI;
+
+/**
+ * Element supporting "sequential focus navigation" using the 'tabindex' attribute.
+ *
+ * @abstract
+ */
+trait TabIndexedElement {
+       /**
+        * Tab index value.
+        *
+        * @var number|null
+        */
+       protected $tabIndex = null;
+
+       /**
+        * @var Element
+        */
+       protected $tabIndexed;
+
+       /**
+        * @param array $config Configuration options
+        * @param string|number|null $config['tabIndex'] Tab index value. Use 0 to use default ordering,
+        *   use -1 to prevent tab focusing, use null to suppress the `tabindex` attribute. (default: 0)
+        */
+       public function initializeTabIndexedElement( array $config = [] ) {
+               // Properties
+               $this->tabIndexed = isset( $config['tabIndexed'] ) ? $config['tabIndexed'] : $this;
+
+               // Initialization
+               $this->setTabIndex( isset( $config['tabIndex'] ) ? $config['tabIndex'] : 0 );
+
+               $this->registerConfigCallback( function ( &$config ) {
+                       if ( $this->tabIndex !== 0 ) {
+                               $config['tabIndex'] = $this->tabIndex;
+                       }
+               } );
+       }
+
+       /**
+        * Set tab index value.
+        *
+        * @param string|number|null $tabIndex Tab index value or null for no tab index
+        * @return $this
+        */
+       public function setTabIndex( $tabIndex ) {
+               $tabIndex = preg_match( '/^-?\d+$/', $tabIndex ) ? (int)$tabIndex : null;
+
+               if ( $this->tabIndex !== $tabIndex ) {
+                       $this->tabIndex = $tabIndex;
+                       $this->updateTabIndex();
+               }
+
+               return $this;
+       }
+
+       /**
+        * Update the tabIndex attribute, in case of changes to tabIndex or disabled
+        * state.
+        *
+        * @return $this
+        */
+       public function updateTabIndex() {
+               $disabled = $this->isDisabled();
+               if ( $this->tabIndex !== null ) {
+                       $this->tabIndexed->setAttributes( [
+                               // Do not index over disabled elements
+                               'tabindex' => $disabled ? -1 : $this->tabIndex,
+                               // ChromeVox and NVDA do not seem to inherit this from parent elements
+                               'aria-disabled' => ( $disabled ? 'true' : 'false' )
+                       ] );
+               } else {
+                       $this->tabIndexed->removeAttributes( [ 'tabindex', 'aria-disabled' ] );
+               }
+               return $this;
+       }
+
+       /**
+        * Get tab index value.
+        *
+        * @return number|null Tab index value
+        */
+       public function getTabIndex() {
+               return $this->tabIndex;
+       }
+
+       /**
+        * Get an ID of a focusable element of this widget, if any, to be used for `<label for>` value.
+        *
+        * If the element already has an ID then that is returned, otherwise unique ID is
+        * generated, set on the element, and returned.
+        *
+        * @return string|null The ID of the focusable element
+        */
+       public function getInputId() {
+               $id = $this->tabIndexed->getAttribute( 'id' );
+
+               if ( !$this->isLabelableNode( $this->tabIndexed ) ) {
+                       return null;
+               }
+
+               if ( $id === null ) {
+                       $id = Tag::generateElementId();
+                       $this->tabIndexed->setAttributes( [ 'id' => $id ] );
+               }
+
+               return $id;
+       }
+
+       /**
+        * Whether the node is 'labelable' according to the HTML spec
+        * (i.e., whether it can be interacted with through a `<label for="…">`).
+        * See: <https://html.spec.whatwg.org/multipage/forms.html#category-label>.
+        *
+        * @param Tag $tag
+        * @return boolean
+        */
+       private function isLabelableNode( Tag $tag ) {
+               $labelableTags = [ 'button', 'meter', 'output', 'progress', 'select', 'textarea' ];
+               $tagName = strtolower( $tag->getTag() );
+
+               if ( $tagName === 'input' && $tag->getAttribute( 'type' ) !== 'hidden' ) {
+                       return true;
+               }
+               if ( in_array( $tagName, $labelableTags, true ) ) {
+                       return true;
+               }
+               return false;
+       }
+}