Generate JetSmartFilters options from JetEngine Query

JE_Query_Filter_Options_Generator.php

<?php

class JE_Query_Filter_Options_Generator {
	
	public function __construct() {
		add_action( 'plugins_loaded', array( $this, 'maybe_add_filters' ) );
	}
	
	public function maybe_add_filters() {
		
		if ( ! function_exists( 'jet_engine' ) ) {
			return;
		}
		
		add_filter( 'jet-smart-filters/post-type/meta-fields-settings', array( $this, 'add_options_to_list' ) );
		add_filter( 'jet-smart-filters/filters/filter-options', array( $this, 'apply_filter_options' ), 9999, 3 );
		
	}

	public function add_options_to_list( $fields ) {

		$queries = array(
				'' => __( 'Select query...', 'jet-engine' ),
			);

		$queries = $queries + Jet_Engine\Query_Builder\Manager::instance()->get_queries_for_options();

		$insert = array(
				'_je_query_use_query' => array(
						'title'   => __( 'Use JetEngine Query to generate options from', 'jet-smart-filters' ),
						'type'    => 'switcher',
						'element' => 'control',
						'conditions' => array(
							'_filter_type' => array( 'checkboxes', 'radio', 'select' ),
						),
					),
				'_je_query_id' => array(
					'title'   => __( 'Select query', 'jet-engine' ),
					'type'    => 'select',
					'element' => 'control',
					'options' => $queries,
					'conditions' => array(
						'_filter_type' => array( 'checkboxes', 'select', 'radio' ),
						'_je_query_use_query' => array( true, 'true', '1' ),
					),
				),
				'_je_query_value' => array(
						'title'   => __( 'Property to get value from', 'jet-engine' ),
						'type'    => 'text',
						'value'   => 'ID',
						'element' => 'control',
						'conditions' => array(
							'_filter_type' => array( 'checkboxes', 'select', 'radio' ),
							'_je_query_use_query' => array( true, 'true', '1' ),
						),
					),
				'_je_query_label' => array(
						'title'   => __( 'Property to get label from', 'jet-engine' ),
						'type'    => 'text',
						'value'   => 'post_title',
						'element' => 'control',
						'conditions' => array(
							'_filter_type' => array( 'checkboxes', 'select', 'radio' ),
							'_je_query_use_query' => array( true, 'true', '1' ),
						),
					),
			);

		return $this->je_insert_after( $fields, '_source_post_type', $insert );

	}

	public function apply_filter_options( $options, $filter_id, $filter ) {

		$use_query = get_post_meta( $filter_id, '_je_query_use_query', true );
		$use_query = filter_var( $use_query, FILTER_VALIDATE_BOOLEAN );
		
		if ( ! $use_query ) {
			return $options;
		}

		$query_id = get_post_meta( $filter_id, '_je_query_id', true );

		if ( ! $query_id ) {
			return $options;
		}
		
		$query = Jet_Engine\Query_Builder\Manager::instance()->get_query_by_id( $query_id );
		
		if ( ! $query ) {
			return $options;
		}

		$value_prop = get_post_meta( $filter_id, '_je_query_value', true );
		$label_prop = get_post_meta( $filter_id, '_je_query_label', true );

		$objects = $query->get_items();

		$new_options = array();
		
		foreach ($objects as $object) {

			$value = isset( $object->$value_prop ) ? $object->$value_prop : false;
			$label = isset( $object->$label_prop ) ? $object->$label_prop : false;
			
			if ( $value && $label && ! isset( $new_options[ $value ] ) ) {
				$new_options[ $value ] = $label;
			}
		}

		$type = get_post_meta( $filter_id, '_filter_type', true );
		
		switch( $type ) {

			case 'select':
				$placeholder = get_post_meta( $filter_id, '_placeholder', true );

				if ( ! $placeholder ) {
					$placeholder = __( 'Select...', 'jet-engine' );
				}

				$new_options = array( '' => $placeholder ) + $new_options;
				break;
			case 'radio':
			case 'checkboxes':
				$source = get_post_meta( $filter_id, '_data_source', true );
				if ( $source === 'taxonomies' ) {
					$tax = get_post_meta( $filter_id, '_source_taxonomy', true );
					$by_parents = get_post_meta( $filter_id, '_group_by_parent', true );
					$by_parents = filter_var( $by_parents, FILTER_VALIDATE_BOOLEAN );
					if ( $by_parents ) {
						foreach ( $new_options as $term_id => $term_name ) {
							$term = get_term( $term_id, $tax );
							if ( ! $term || is_wp_error( $term ) ) {
								continue;
							}
							$new_options[$term_id] = $term;
						}
					}
				}
				if ( $type === 'radio' ) {
					
					$add_all_option   = filter_var( get_post_meta( $filter_id, '_add_all_option', true ), FILTER_VALIDATE_BOOLEAN );
					$all_option_label = $add_all_option ? get_post_meta( $filter_id, '_all_option_label', true ) : false;
					
					if ( $all_option_label ) {
						if ( true === $by_parents ) {
							$all_option = (object) array( 
								'term_id' => 'all',
								'name' => htmlspecialchars( $all_option_label )
							);
						} else {
							$all_option = htmlspecialchars( $all_option_label );
						}

						$new_options = array( 'all' => $all_option ) + $new_options;
					}	
					
				}
				break;
		}
		
		return $new_options;
			
	}

	public function je_insert_after( $source = array(), $after = null, $insert = array() ) {

		$keys   = array_keys( $source );
		$index  = array_search( $after, $keys );

		if ( ! $source ) {
			$source = array();
		}

		if ( false === $index ) {
			return $source + $insert;
		}

		$offset = $index + 1;

		return array_slice( $source, 0, $offset, true ) + $insert + array_slice( $source, $offset, null, true );

	}
}

new JE_Query_Filter_Options_Generator();

Taxonomy_Filter_Manual_Options.php

<?php

class Taxonomy_Filter_Manual_Options {
	
	public function __construct() {
		
		add_filter( 'jet-smart-filters/query/final-query', array( $this, 'modify_query' ) );
		add_filter( 'jet-smart-filters/query/meta-query-row', array( $this, 'clear_meta_row' ) );
		
	}
	
	public function modify_query( $query ) {
    
		if ( isset( $query['tax_query'] ) ) {

			foreach ( $query['tax_query'] as $index => $item ) {
				if ( is_array( $item ) && false !== strpos( $item['taxonomy'], '_meta_query_' ) ) {
					$query['tax_query'][$index]['taxonomy'] = str_replace( '_meta_query_', '', $item['taxonomy'] );
				}
			}

		}

		return $query;

	}
	
	public function clear_meta_row( $row ) {

		if ( false !== strpos( $row['key'], '_tax_query_' ) ) {
			$row = array();
		}

		return $row;

	}
	
}

new Taxonomy_Filter_Manual_Options();