<?php
/**
* WordPress List utility class
*
* @package WordPress
* @since 4.7.0
*/
/**
* List utility.
*
* Utility class to handle operations on an array of objects or arrays.
*
* @since 4.7.0
*/
class WP_List_Util {
/**
* The input array.
*
* @since 4.7.0
* @var array
*/
private $input = array();
/**
* The output array.
*
* @since 4.7.0
* @var array
*/
private $output = array();
/**
* Temporary arguments for sorting.
*
* @since 4.7.0
* @var string[]
*/
private $orderby = array();
/**
* Constructor.
*
* Sets the input array.
*
* @since 4.7.0
*
* @param array $input Array to perform operations on.
*/
public function __construct( $input ) {
$this->output = $input;
$this->input = $input;
}
/**
* Returns the original input array.
*
* @since 4.7.0
*
* @return array The input array.
*/
public function get_input() {
return $this->input;
}
/**
* Returns the output array.
*
* @since 4.7.0
*
* @return array The output array.
*/
public function get_output() {
return $this->output;
}
/**
* Filters the list, based on a set of key => value arguments.
*
* Retrieves the objects from the list that match the given arguments.
* Key represents property name, and value represents property value.
*
* If an object has more properties than those specified in arguments,
* that will not disqualify it. When using the 'AND' operator,
* any missing properties will disqualify it.
*
* @since 4.7.0
*
* @param array $args Optional. An array of key => value arguments to match
* against each object. Default empty array.
* @param string $operator Optional. The logical operation to perform. 'AND' means
* all elements from the array must match. 'OR' means only
* one element needs to match. 'NOT' means no elements may
* match. Default 'AND'.
* @return array Array of found values.
*/
public function filter( $args = array(), $operator = 'AND' ) {
if ( empty( $args ) ) {
return $this->output;
}
$operator = strtoupper( $operator );
if ( ! in_array( $operator, array( 'AND', 'OR', 'NOT' ), true ) ) {
$this->output = array();
return $this->output;
}
$count = count( $args );
$filtered = array();
foreach ( $this->output as $key => $obj ) {
$matched = 0;
foreach ( $args as $m_key => $m_value ) {
if ( is_array( $obj ) ) {
// Treat object as an array.
if ( array_key_exists( $m_key, $obj ) && ( $m_value == $obj[ $m_key ] ) ) {
$matched++;
}
} elseif ( is_object( $obj ) ) {
// Treat object as an object.
if ( isset( $obj->{$m_key} ) && ( $m_value == $obj->{$m_key} ) ) {
$matched++;
}
}
}
if ( ( 'AND' === $operator && $matched === $count )
|| ( 'OR' === $operator && $matched > 0 )
|| ( 'NOT' === $operator && 0 === $matched )
) {
$filtered[ $key ] = $obj;
}
}
$this->output = $filtered;
return $this->output;
}
/**
* Plucks a certain field out of each element in the input array.
*
* This has the same functionality and prototype of
* array_column() (PHP 5.5) but also supports objects.
*
* @since 4.7.0
*
* @param int|string $field Field to fetch from the object or array.
* @param int|string $index_key Optional. Field from the element to use as keys for the new array.
* Default null.
* @return array Array of found values. If `$index_key` is set, an array of found values with keys
* corresponding to `$index_key`. If `$index_key` is null, array keys from the original
* `$list` will be preserved in the results.
*/
public function pluck( $field, $index_key = null ) {
$newlist = array();
if ( ! $index_key ) {
/*
* This is simple. Could at some point wrap array_column()
* if we knew we had an array of arrays.
*/
foreach ( $this->output as $key => $value ) {
if ( is_object( $value ) ) {
$newlist[ $key ] = $value->$field;
} else {
$newlist[ $key ] = $value[ $field ];
}
}
$this->output = $newlist;
return $this->output;
}
/*
* When index_key is not set for a particular item, push the value
* to the end of the stack. This is how array_column() behaves.
*/
foreach ( $this->output as $value ) {
if ( is_object( $value ) ) {
if ( isset( $value->$index_key ) ) {
$newlist[ $value->$index_key ] = $value->$field;
} else {
$newlist[] = $value->$field;
}
} else {
if ( isset( $value[ $index_key ] ) ) {
$newlist[ $value[ $index_key ] ] = $value[ $field ];
} else {
$newlist[] = $value[ $field ];
}
}
}
$this->output = $newlist;
return $this->output;
}
/**
* Sorts the input array based on one or more orderby arguments.
*
* @since 4.7.0
*
* @param string|array $orderby Optional. Either the field name to order by or an array
* of multiple orderby fields as $orderby => $order.
* @param string $order Optional. Either 'ASC' or 'DESC'. Only used if $orderby
* is a string.
* @param bool $preserve_keys Optional. Whether to preserve keys. Default false.
* @return array The sorted array.
*/
public function sort( $orderby = array(), $order = 'ASC', $preserve_keys = false ) {
if ( empty( $orderby ) ) {
return $this->output;
}
if ( is_string( $orderby ) ) {
$orderby = array( $orderby => $order );
}
foreach ( $orderby as $field => $direction ) {
$orderby[ $field ] = 'DESC' === strtoupper( $direction ) ? 'DESC' : 'ASC';
}
$this->orderby = $orderby;
if ( $preserve_keys ) {
uasort( $this->output, array( $this, 'sort_callback' ) );
} else {
usort( $this->output, array( $this, 'sort_callback' ) );
}
$this->orderby = array();
return $this->output;
}
/**
* Callback to sort an array by specific fields.
*
* @since 4.7.0
*
* @see WP_List_Util::sort()
*
* @param object|array $a One object to compare.
* @param object|array $b The other object to compare.
* @return int 0 if both objects equal. -1 if second object should come first, 1 otherwise.
*/
private function sort_callback( $a, $b ) {
if ( empty( $this->orderby ) ) {
return 0;
}
$a = (array) $a;
$b = (array) $b;
foreach ( $this->orderby as $field => $direction ) {
if ( ! isset( $a[ $field ] ) || ! isset( $b[ $field ] ) ) {
continue;
}
if ( $a[ $field ] == $b[ $field ] ) {
continue;
}
$results = 'DESC' === $direction ? array( 1, -1 ) : array( -1, 1 );
if ( is_numeric( $a[ $field ] ) && is_numeric( $b[ $field ] ) ) {
return ( $a[ $field ] < $b[ $field ] ) ? $results[0] : $results[1];
}
return 0 > strcmp( $a[ $field ], $b[ $field ] ) ? $results[0] : $results[1];
}
return 0;
}
}