<?php
/**
* Taxonomy API: Walker_Category class
*
* @package WordPress
* @subpackage Template
* @since 4.4.0
*/

/**
* Core class used to create an HTML list of categories.
*
* @since 2.1.0
*
* @see Walker
*/
class Walker_Category extends Walker {

/**
* What the class handles.
*
* @since 2.1.0
* @var string
*
* @see Walker::$tree_type
*/
public $tree_type = 'category';

/**
* Database fields to use.
*
* @since 2.1.0
* @var string[]
*
* @see Walker::$db_fields
* @todo Decouple this
*/
public $db_fields = array(
'parent' => 'parent',
'id' => 'term_id',
);

/**
* Starts the list before the elements are added.
*
* @since 2.1.0
*
* @see Walker::start_lvl()
*
* @param string $output Used to append additional content. Passed by reference.
* @param int $depth Optional. Depth of category. Used for tab indentation. Default 0.
* @param array $args Optional. An array of arguments. Will only append content if style argument
* value is 'list'. See wp_list_categories(). Default empty array.
*/
public function start_lvl( &$output, $depth = 0, $args = array() ) {
if ( 'list' !== $args['style'] ) {
return;
}

$indent = str_repeat( "\t", $depth );
$output .= "$indent<ul class='children'>\n";
}

/**
* Ends the list of after the elements are added.
*
* @since 2.1.0
*
* @see Walker::end_lvl()
*
* @param string $output Used to append additional content. Passed by reference.
* @param int $depth Optional. Depth of category. Used for tab indentation. Default 0.
* @param array $args Optional. An array of arguments. Will only append content if style argument
* value is 'list'. See wp_list_categories(). Default empty array.
*/
public function end_lvl( &$output, $depth = 0, $args = array() ) {
if ( 'list' !== $args['style'] ) {
return;
}

$indent = str_repeat( "\t", $depth );
$output .= "$indent</ul>\n";
}

/**
* Starts the element output.
*
* @since 2.1.0
* @since 5.9.0 Renamed `$category` to `$data_object` and `$id` to `$current_object_id`
* to match parent class for PHP 8 named parameter support.
*
* @see Walker::start_el()
*
* @param string $output Used to append additional content (passed by reference).
* @param WP_Term $data_object Category data object.
* @param int $depth Optional. Depth of category in reference to parents. Default 0.
* @param array $args Optional. An array of arguments. See wp_list_categories().
* Default empty array.
* @param int $current_object_id Optional. ID of the current category. Default 0.
*/
public function start_el( &$output, $data_object, $depth = 0, $args = array(), $current_object_id = 0 ) {
// Restores the more descriptive, specific name for use within this method.
$category = $data_object;

/** This filter is documented in wp-includes/category-template.php */
$cat_name = apply_filters( 'list_cats', esc_attr( $category->name ), $category );

// Don't generate an element if the category name is empty.
if ( '' === $cat_name ) {
return;
}

$atts = array();
$atts['href'] = get_term_link( $category );

if ( $args['use_desc_for_title'] && ! empty( $category->description ) ) {
/**
* Filters the category description for display.
*
* @since 1.2.0
*
* @param string $description Category description.
* @param WP_Term $category Category object.
*/
$atts['title'] = strip_tags( apply_filters( 'category_description', $category->description, $category ) );
}

/**
* Filters the HTML attributes applied to a category list item's anchor element.
*
* @since 5.2.0
*
* @param array $atts {
* The HTML attributes applied to the list item's `<a>` element, empty strings are ignored.
*
* @type string $href The href attribute.
* @type string $title The title attribute.
* }
* @param WP_Term $category Term data object.
* @param int $depth Depth of category, used for padding.
* @param array $args An array of arguments.
* @param int $current_object_id ID of the current category.
*/
$atts = apply_filters( 'category_list_link_attributes', $atts, $category, $depth, $args, $current_object_id );

$attributes = '';
foreach ( $atts as $attr => $value ) {
if ( is_scalar( $value ) && '' !== $value && false !== $value ) {
$value = ( 'href' === $attr ) ? esc_url( $value ) : esc_attr( $value );
$attributes .= ' ' . $attr . '="' . $value . '"';
}
}

$link = sprintf(
'<a%s>%s</a>',
$attributes,
$cat_name
);

if ( ! empty( $args['feed_image'] ) || ! empty( $args['feed'] ) ) {
$link .= ' ';

if ( empty( $args['feed_image'] ) ) {
$link .= '(';
}

$link .= '<a href="' . esc_url( get_term_feed_link( $category, $category->taxonomy, $args['feed_type'] ) ) . '"';

if ( empty( $args['feed'] ) ) {
/* translators: %s: Category name. */
$alt = ' alt="' . sprintf( __( 'Feed for all posts filed under %s' ), $cat_name ) . '"';
} else {
$alt = ' alt="' . $args['feed'] . '"';
$name = $args['feed'];
$link .= empty( $args['title'] ) ? '' : $args['title'];
}

$link .= '>';

if ( empty( $args['feed_image'] ) ) {
$link .= $name;
} else {
$link .= "<img src='" . esc_url( $args['feed_image'] ) . "'$alt" . ' />';
}

$link .= '</a>';

if ( empty( $args['feed_image'] ) ) {
$link .= ')';
}
}

if ( ! empty( $args['show_count'] ) ) {
$link .= ' (' . number_format_i18n( $category->count ) . ')';
}

if ( 'list' === $args['style'] ) {
$output .= "\t<li";
$css_classes = array(
'cat-item',
'cat-item-' . $category->term_id,
);

if ( ! empty( $args['current_category'] ) ) {
// 'current_category' can be an array, so we use `get_terms()`.
$_current_terms = get_terms(
array(
'taxonomy' => $category->taxonomy,
'include' => $args['current_category'],
'hide_empty' => false,
)
);

foreach ( $_current_terms as $_current_term ) {
if ( $category->term_id === $_current_term->term_id ) {
$css_classes[] = 'current-cat';
$link = str_replace( '<a', '<a aria-current="page"', $link );
} elseif ( $category->term_id === $_current_term->parent ) {
$css_classes[] = 'current-cat-parent';
}

while ( $_current_term->parent ) {
if ( $category->term_id === $_current_term->parent ) {
$css_classes[] = 'current-cat-ancestor';
break;
}

$_current_term = get_term( $_current_term->parent, $category->taxonomy );
}
}
}

/**
* Filters the list of CSS classes to include with each category in the list.
*
* @since 4.2.0
*
* @see wp_list_categories()
*
* @param string[] $css_classes An array of CSS classes to be applied to each list item.
* @param WP_Term $category Category data object.
* @param int $depth Depth of page, used for padding.
* @param array $args An array of wp_list_categories() arguments.
*/
$css_classes = implode( ' ', apply_filters( 'category_css_class', $css_classes, $category, $depth, $args ) );
$css_classes = $css_classes ? ' class="' . esc_attr( $css_classes ) . '"' : '';

$output .= $css_classes;
$output .= ">$link\n";
} elseif ( isset( $args['separator'] ) ) {
$output .= "\t$link" . $args['separator'] . "\n";
} else {
$output .= "\t$link<br />\n";
}
}

/**
* Ends the element output, if needed.
*
* @since 2.1.0
* @since 5.9.0 Renamed `$page` to `$data_object` to match parent class for PHP 8 named parameter support.
*
* @see Walker::end_el()
*
* @param string $output Used to append additional content (passed by reference).
* @param object $data_object Category data object. Not used.
* @param int $depth Optional. Depth of category. Not used.
* @param array $args Optional. An array of arguments. Only uses 'list' for whether should
* append to output. See wp_list_categories(). Default empty array.
*/
public function end_el( &$output, $data_object, $depth = 0, $args = array() ) {
if ( 'list' !== $args['style'] ) {
return;
}

$output .= "</li>\n";
}
}