<?php

defined( 'ABSPATH' ) or die( 'Access denied' );

if( ! class_exists('A_W_F_frontend') ) {

  class A_W_F_frontend {
    
    /** Current running instance of A_W_F_frontend object
     *
     * @since 1.0.0
     * @var A_W_F_frontend object
     */
    private static $instance;
    
    public $filters_manager;

    public $awf_settings = array();

    public $filter_on = false;

    public $awf_var_names = array(
      'orderby' => 'orderby', // wc - hardcoded
      'search' => 's', // wc - hardcoded
      'ppp' => 'ppp',
      'min_price' => 'min_price',
      'max_price' => 'max_price',
      'min_rating' => 'min_rating',
      'max_rating' => 'max_rating',
      'stock' => 'availability',
      'featured' => 'featured',
      'onsale' => 'onsale',
    );
    public $tax_var_names = array( 'product_tag' => 'product-tags', 'product_cat' => 'product-categories' );
    public $unregistered_tax_vars = array();
    public $query;
    public $url_query;
    public $page_associations;
    public $shop_on_frontpage;
    public $shop_page_id;
    public $shop_url;
    public $current_url;

    public $permalinks_on = false;
    public $archived_taxonomies;
    public $cat_url_template;
    private $cat_names = '';

    private $is_wp_page = false;
    private $is_sc_page = false;

    public $counts_cache_name;
    public $counts;
    public $update_counts_cache;

    private function __construct() {
      
      $this->query = (object) array( 'awf' => array(), 'tax' => array() );

      add_action( 'init', array( $this, 'initialize'), 20 );
      add_filter( 'query_vars', array( $this, 'register_query_vars' ) );
      add_action( 'pre_get_posts', array( $this, 'before_wc_query' ), 0 );
      add_action( 'template_redirect', array( $this, 'redirect_archives' ), 20 );
      //add_action( 'woocommerce_product_query', array( $this, 'wc_query' ), 50, 2 );
      //add_action( 'pre_get_posts', array( $this, 'after_wc_query' ), 20 );
      add_action( 'wp_enqueue_scripts', array( $this, 'enqueue_scripts'), 10 );
      add_action( 'shutdown', array( $this, 'update_counts_cache') );
      
      $this->filters_manager = 'A_W_F_filter_frontend';
    }

    public function ajax_controller() {

      if( 'filter' === $_GET['awf_action'] ) {
        $sc_args; $sc;
        
        if( isset( $_GET['awf_sc_page'] ) ) {
          $this->is_sc_page = (int) $_GET['awf_sc_page'];
          $this->initialize();

          add_filter( 'shortcode_atts_products', array( $this, 'add_awf_sc_class' ) );
          add_action( 'woocommerce_shortcode_before_products_loop', array( $this, 'insert_sc_ajax_vars' ) );
          add_action( 'woocommerce_shortcode_products_loop_no_results', array( $this, 'insert_sc_ajax_vars' ) );

          $sc_args = isset( $_GET['awf_sc'] ) ? $_GET['awf_sc'] : array();

        } else {
          $this->initialize();

          $sc_args = array( 'paginate' => true );

          if( ! empty( $this->awf_settings['shop_columns'] ) ) { $sc_args['columns'] = $this->awf_settings['shop_columns']; }
          
          if( empty( $this->awf_settings['ppp_default'] ) ) { $sc_args['limit'] = get_option( 'posts_per_page', 12 ); }
          else { $sc_args['limit'] = $this->awf_settings['ppp_default']; }
        }

        $this->build_ajax_queries();
        
        add_filter( 'woocommerce_shortcode_products_query', array( $this, 'wc_shortcode_query' ), 10, 3 );
        add_filter( 'woocommerce_pagination_args', array( $this, 'adjust_wc_pagination' ) );
        
        add_filter( 'paginate_links', function( $href ) { 
          $remove_pagination_args = array_keys( $_REQUEST );
          if( ! empty( $this->awf_settings['cat_views_on'] ) && ! empty( $this->permalinks_on ) ) {
            $remove_pagination_args[] = 'product_cat';
          }
          return remove_query_arg( $remove_pagination_args, $href );
        });
        add_action( 'woocommerce_shortcode_products_loop_no_results', array( $this, 'display_no_results_msg' ) );

        if( ! isset( $this->query->awf['orderby'] ) ) {
          $sc_args['orderby'] = 'popularity';
        }

        $sc = '[products';
        foreach( $sc_args as $k => $v ) {
          if( ! empty( $v ) ) {
            if( in_array( $k, array( 'limit', 'columns', 'rows', 'page' ) ) ) {
             $sc .= ' ' . $k . '="' . intval( $v ) . '"';
              
            } else {
             $sc .= ' ' . sanitize_key( $k ) . '="' . sanitize_title_for_query( $v ) . '"';
            }
          }
        }
        $sc .= ']';

        echo do_shortcode( $sc );

      } else if( 'update_filters' === $_GET['awf_action'] ) {

  //      $microtime = microtime();

        $response = array();
        $this->awf_settings['cat_views_on'] = ( 'yes' === get_option( 'awf_cat_views_on' ) );
        $this->awf_settings['include_children'] = ( 'yes' === get_option( 'awf_include_children_on', 'yes' ) );
        $this->set_query_vars();
        $this->build_ajax_queries();

        // @ToDo remove excluded taxonomy
        $excluded_taxonomy = sanitize_text_field( $_GET['awf_exclude_taxonomy'] );

        ksort( $this->query->tax );
        ksort( $this->query->awf );

        array_walk( $this->query->tax, function( &$value, $key ) {
          if( is_array( $value ) ) { sort( $value ); }
        });

        array_walk( $this->query->awf, function( &$value, $key ) {
          if( is_array( $value ) ) { sort( $value ); }
        });

        unset( $this->query->awf['orderby'] );
        unset( $this->query->awf['ppp'] );

        $this->counts_cache_name = 'awf_counts_' . md5( wp_json_encode( $this->query ) );
        $this->counts = get_transient( $this->counts_cache_name );
        if( false === $this->counts ) { $this->counts = array(); }

        foreach( $_GET['awf_callers'] as $caller ) {
          $caller = sanitize_text_field( $caller );

          $pieces = substr( $caller, 0, -strlen( '-wrapper' ) );
          $pieces = explode( '-', $pieces );
          $preset_id = (int) array_pop( $pieces );

          if( isset( A_W_F::$presets[$preset_id] ) ) { $preset = new A_W_F_preset_frontend( $preset_id ); }
        }

        if( true === $this->update_counts_cache && ! empty( $this->counts ) ) {
          set_transient( $this->counts_cache_name, $this->counts, DAY_IN_SECONDS * 30 );
        }

        foreach( $this->counts as $taxonomy => $counts ) {
          $response['counts'][$this->tax_var_names[$taxonomy]] = $counts;
        }
        
  //      $response['time'] = microtime() - $microtime ;
        echo( json_encode( $response ) );
      }

      die();
    }

    private function build_ajax_queries() {

      if( empty( $_GET['awf_query'] ) ) { return; }

      foreach( $_GET['awf_query'] as $var => $value ) {

        if( 'product_cat' === $var ) { $var = $this->tax_var_names['product_cat']; }

        if( ( false !== ( $taxonomy = array_search( $var, $this->tax_var_names ) ) ) ) {
          $terms = array_map( 'sanitize_text_field', explode( ',', $value ) );

          if( 'product_cat' === $taxonomy ) {
            if( isset( $this->query->tax['product_cat'] ) ) {
              $this->query->tax['product_cat'] = array_merge( $this->query->tax['product_cat'], $terms );
            } else {
              $this->query->tax['product_cat'] = $terms;
            }

          } else {
            $this->query->tax[$taxonomy] = $terms;
          }

        } else if( false !== ( $awf_var_name = array_search( $var, $this->awf_var_names ) ) ) {
          $this->query->awf[$awf_var_name] = sanitize_text_field( $value );
        }
      }
      
      if( isset( $this->query->tax['product_cat'] ) ) {
        $this->query->tax['product_cat'] = array_unique( $this->query->tax['product_cat'] );

        if( ! empty( $this->awf_settings['cat_views_on'] ) ) {
          $this->current_url = str_replace( 'awf-insert-product-cats', implode( ',', $this->query->tax['product_cat'] ), $this->cat_url_template );
        }
      }
      
      if( 'filter' === $_GET['awf_action'] ) { $_GET = $this->get_url_query(); }
    }

    public function initialize() {

      $this->shop_page_id = wc_get_page_id( 'shop' );
      if( 'page' === get_option( 'show_on_front' ) && intval( get_option( 'page_on_front' ) ) === $this->shop_page_id ) {
        $this->shop_on_frontpage = true;
      }

      $this->set_awf_settings();
      $this->set_query_vars();
      $this->setup_urls();

      if( isset( $_POST['awf_submit'] ) ) {

        $url_query = array();
        foreach( $_POST as $var => $value ) {
          if( is_array( $value ) ) $value = implode( ',', $value );
          if( ! empty( $value ) ) { $url_query[$var] = $value; }
        }
        unset( $url_query['awf_submit'] );
        
        if( ! empty( $this->shop_on_frontpage ) && empty( $this->is_sc_page )
           && ( ! empty( $url_query['s'] ) || ! empty( $url_query['orderby'] ) )
        ) {
          $url_query['post_type'] = 'product';
        }
        
        $url = $this->shop_url;
        
        if( isset( $url_query[$this->tax_var_names['product_cat']] ) && ! empty( $this->awf_settings['cat_views_on'] ) ) {
          $url = str_replace( 'awf-insert-product-cats', $url_query[$this->tax_var_names['product_cat']], $this->cat_url_template );
          unset( $url_query[$this->tax_var_names['product_cat']] );
        }

        $url = add_query_arg( $url_query, $url );

        wp_redirect( esc_url_raw( $url ) );
        exit();
      }
    }

    private function set_awf_settings() {
      if( false === $this->is_sc_page ) {
        $this->awf_settings['cat_views_on'] = ( 'yes' === get_option( 'awf_cat_views_on' ) );
      }

      if( 0 < ( $this->awf_settings['shop_columns'] = (int) get_option( 'awf_shop_columns', 0 ) ) && ! wp_doing_ajax() ) {
        add_filter( 'loop_shop_columns', array( $this, 'set_shop_columns' ) );
      }

      $this->awf_settings['ppp_default'] = (int) get_option( 'awf_ppp_default', 0 );
      if( ! wp_doing_ajax() ) { add_filter('loop_shop_per_page', array( $this, 'set_products_per_page' ) ); }

      $this->awf_settings['include_children'] = ( 'yes' === get_option( 'awf_include_children_on', 'yes' ) );
    }

    public function set_query_vars() {

      $taxonomies = get_object_taxonomies( 'product', 'objects' );

      foreach( $taxonomies as $t ) {

        if( in_array( $t->name, A_W_F::$excluded_taxonomies ) ) continue;
        
        if( ! empty( $t->rewrite ) ) { $this->archived_taxonomies[$t->name]; }

        if( empty( $t->query_var ) ) {
          $this->unregistered_tax_vars[] = $t->name;
          $taxonomy_var_name = $t->name;
        } else {
          $taxonomy_var_name = $t->query_var;
        }

        if( ! isset( $this->tax_var_names[$t->name] ) ) {
          if( $pretty_name_from_options = get_option( 'awf_' . $t->name . '_pretty_name', false ) ) {
            $this->tax_var_names[$t->name] = $pretty_name_from_options;
          } else {
            $this->tax_var_names[$t->name] = $taxonomy_var_name;
          }
        }
      }

      if( ! empty( $this->awf_settings['cat_views_on'] ) ) {
        $this->tax_var_names['product_cat'] = 'product_cat';
      }
      
      foreach( $this->awf_var_names as $var => $name ) {
        $pretty_name = get_option( 'awf_' . $var . '_pretty_name', '' );
        if( ! empty( $pretty_name ) ) {
          $this->awf_var_names[$var] = $pretty_name;
        }
      }
    }

    public function setup_urls() {

      $this->permalinks_on = ! empty( get_option( 'permalink_structure' ) );

      if ( false !== $this->is_sc_page ) {
        $this->shop_url = $this->current_url = get_permalink( $this->is_sc_page );

      } elseif( ! empty( $this->shop_on_frontpage ) ) {
        $this->shop_url = $this->current_url = get_home_url() . '/';

      } else {
        if( $this->permalinks_on ) {
          $this->shop_url = $this->current_url = get_permalink( $this->shop_page_id );

        } else {
          $this->shop_url = $this->current_url = get_post_type_archive_link( 'product' );
        }

      }

      if( ! empty( $this->awf_settings['cat_views_on'] ) ) {

        $bases = wc_get_permalink_structure();
        $a_cat = get_terms( array( 'taxonomy' => 'product_cat', 'parent' => 0, 'fields' => 'slugs', 'number' => 1 ) );

        if( ! empty( $a_cat ) ) {
          $a_cat_url = get_term_link( $a_cat[0], 'product_cat' );

          if ( $this->permalinks_on ) {
            $this->cat_url_template = str_replace(
              '/' . $bases['category_rewrite_slug'] . '/' . $a_cat[0] . '/',
              '/' . $bases['category_rewrite_slug'] . '/awf-insert-product-cats/',
              $a_cat_url
            );

          } else {
            $this->cat_url_template = str_replace( 'product_cat=' . $a_cat[0], 'product_cat=awf-insert-product-cats', $a_cat_url );
          }

        } else {
          $this->awf_settings['cat_views_on'] = false;
        }
      }
    }

    public function register_query_vars( $vars ) {

      foreach( $this->tax_var_names as $var ) {
        if( ! in_array( $var, $vars ) ) { $vars[] = $var; }
      }

      foreach( $this->awf_var_names as $var ) {
        if( ! in_array( $var, $vars ) ) { $vars[] = $var; }
      }

      return $vars;
    }

    public function before_wc_query( $query ) {

      if( ! $query->is_main_query() || is_admin() ) { return; }

      if( ( (int) $query->get( 'page_id' ) === $this->shop_page_id )
        || ( $query->is_home() && ! empty( $this->shop_on_frontpage ) )
      ) {
        $query->set( 'post_type', 'product' );
        $query->is_singular          = false;
        $query->is_post_type_archive = true;
        $query->is_archive           = true;
      }
      
      if( ! empty( $query->get( 'page_id' ) ) ) {
        $this->is_wp_page = $query->get( 'page_id' ) . '';
      } elseif( $query->queried_object instanceof WP_Post ) {
        $this->is_wp_page = $query->queried_object_id . '';
      }
      
      if( in_array( $this->is_wp_page, get_option( 'awf_shortcode_pages', array() ) ) ) {
        $this->is_sc_page = $this->is_wp_page;
        $this->filter_on = true;
        $this->awf_settings['cat_views_on'] = false;
        $this->permalinks_on = false;
        $this->shop_url = $this->current_url = get_permalink( $this->is_wp_page );

        if( isset( $query->query['s'] ) ) { 
          $this->query->awf['search'] = $query->query['s'];
          unset( $query->query_vars['s'] );
        }

        add_filter( 'woocommerce_shortcode_products_query', array( $this, 'wc_shortcode_query' ), 10, 3 );
        add_filter( 'shortcode_atts_products', array( $this, 'add_awf_sc_class' ) );
        add_action( 'woocommerce_shortcode_before_products_loop', array( $this, 'insert_sc_ajax_vars' ) );
        add_action( 'woocommerce_shortcode_products_loop_no_results', array( $this, 'insert_sc_ajax_vars' ) );
        add_action( 'woocommerce_shortcode_products_loop_no_results', array( $this, 'display_shortcode_no_results_message' ), 20 );

      } else if( ( $query->get( 'post_type' ) === 'product' ) || ! empty( $query->get( 'product_cat' ) ) ) {
        
        $this->filter_on = true;
        
        if( 'yes' === get_option( 'awf_force_products_display_on', 'yes' ) ) { add_filter( 'woocommerce_is_filtered', '__return_true' ); }
        
        add_filter( 'woocommerce_product_query_tax_query', array( $this, 'set_wc_tax_query' ) );
        add_filter( 'woocommerce_product_query_meta_query', array( $this, 'set_wc_meta_query' ) );
        add_filter( 'loop_shop_post_in', array( $this, 'set_wc_post__in' ) );

        add_filter( 'woocommerce_redirect_single_search_result', array( $this, 'redirect_single_search_result' ) );
        add_filter( 'woocommerce_page_title', array( $this, 'adjust_shop_title' ) );
        add_filter( 'woocommerce_get_breadcrumb', array( $this, 'adjust_breadcrumbs' ), 10, 2 );
        add_filter( 'document_title_parts', array( $this, 'adjust_document_title' ) );
      }

      foreach( $query->query as $var => $value ) {

        if( ( false !== ( $var_name = array_search( $var, $this->tax_var_names ) ) ) || ( $var === 'product_cat' ) ) {

          if( is_array( $value ) ) {
            $terms = $value;
          } else {
            $terms = explode( ',', $value );
          }

          if( 'product_cat' === $var_name ) { $var = 'product_cat'; }

          if( 'product_cat' === $var ) {

            if ( $this->permalinks_on ) {
              foreach( $terms as $i => $t ) {
                $t = explode( '/', $t );
                $terms[$i] = array_pop( $t );
              }
            }

            if( isset( $this->query->tax['product_cat'] ) ) {
              $this->query->tax['product_cat'] = array_merge( $this->query->tax['product_cat'], $terms );
            } else {
              $this->query->tax['product_cat'] = $terms;
            }

          } else {
            $this->query->tax[$var_name] = $terms;
          }

        } else if( false !== ( $awf_var_name = array_search( $var, $this->awf_var_names ) ) ) {
          $this->query->awf[$awf_var_name] = $value;
        }
      }

      if( isset( $this->query->tax['product_cat'] ) ) {
        $this->query->tax['product_cat'] = array_unique( $this->query->tax['product_cat'] );
        $query->set( 'product_cat', implode( ',', $this->query->tax['product_cat'] ) );

        if( ! empty( $this->awf_settings['cat_views_on'] ) ) {
          $this->current_url = str_replace( 'awf-insert-product-cats', implode( ',', $this->query->tax['product_cat'] ), $this->cat_url_template );
        }
        
        $cat_names = array();
        foreach( $this->query->tax['product_cat'] as $slug ) {
          $cat_names[] = get_term_by( 'slug', $slug, 'product_cat' )->name;
        }
        $this->cat_names = implode( ', ', $cat_names ) ;

      }
      
      $this->url_query = $this->get_url_query();
    }

    public function wc_shortcode_query( $args, $attrs, $type ) {
            
      if( isset( $this->query->awf['ppp'] ) ) { $args['posts_per_page'] = (int) $this->query->awf['ppp']; }
      
      $tax_query = $this->set_wc_tax_query( array() );

      if( isset( $this->query->tax['product_cat'] ) && ! empty( $attrs['category'] ) ) {

        foreach( $args['tax_query'] as $i => $wc_tax ) {
          if( 'product_cat' === $wc_tax['taxonomy'] ) {
            foreach( $tax_query as $ii => $awf_tax ) {
              if( 'product_cat' === $awf_tax['taxonomy'] ) {
                $args['tax_query'][$i]['terms'] = array_unique( array_merge( $wc_tax['terms'], $awf_tax['terms'] ) );
                $args['tax_query'][$i]['operator'] = $attrs['cat_operator'];
                $args['tax_query'][$i]['include_children'] = $awf_tax['include_children'];
                unset( $tax_query[$ii] );
                break 2;
              }
            }
          }
        }

      }

      $args['tax_query'] = array_merge( $args['tax_query'], $tax_query );

      $meta_query = $this->set_wc_meta_query( array() );
      
      $args['meta_query'] = array_merge( $args['meta_query'], $meta_query );

      $this->set_sc_post__in( $args );
      
      if( isset( $this->query->awf['onsale'] ) ) {
        $postin = isset( $args['post__in'] ) ? $args['post__in'] : array();
        $args['post__in'] = $this->set_wc_post__in( $postin );
      }

      if( isset( $this->query->awf['orderby'] ) ) {
        $pieces = explode( '-', $this->query->awf['orderby'] );
        if( empty( $pieces[1] ) ) { $pieces[1] = 'ASC'; } else {
          $pieces[1] = in_array( strtoupper( $pieces[1] ), array( 'ASC', 'DESC') ) ? strtoupper( $pieces[1] ) : 'ASC' ;
        }

        $ordering_args = WC()->query->get_catalog_ordering_args( $pieces[0], $pieces[1] );
        $args['orderby']        = $ordering_args['orderby'];
        $args['order']          = $ordering_args['order'];
        if ( $ordering_args['meta_key'] ) {
          $args['meta_key']       = $ordering_args['meta_key'];
        }
      }
      
      return $args;
    }

    public function set_wc_tax_query( $query ) {
      
      foreach( $this->query->tax as $var => $terms ) {
        $operator = get_option( 'awf_' . $var . '_query_operator', 'IN' );
        
        $query[] = array(
          'taxonomy' => $var,
          'field' => 'slug',
          'terms' => $terms,
          'operator' => $operator,
          'include_children' => $this->awf_settings['include_children'],
        );
      }

      if( isset( $this->query->awf['stock'] ) ) {
        if( in_array( $this->query->awf['stock'], array( 'instock', 'outofstock' ) ) ) {
          $this->{ 'set_visibility_' . $this->query->awf['stock'] }( $query );
        }      
      }

      if( isset( $this->query->awf['featured'] ) ) {
        $this->set_visibility_featured( $query );
      }
      
      return $query;
    }

    public function set_wc_meta_query( $query ) {

      if( isset( $this->query->awf['stock'] ) && ( 'onbackorder' === $this->query->awf['stock'] ) ) {
        $query[] = array(
          'key' => '_stock_status',
          'value' => 'onbackorder'
        );
      }
      
      if( ( isset( $this->query->awf['min_price'] ) || isset( $this->query->awf['max_price'] ) ) ) {
        
        if( version_compare( WC_VERSION, '3.6', '>=' ) ) {
          add_action( 'woocommerce_product_query', function() {
            remove_filter( 'posts_clauses', array( WC()->query, 'price_filter_post_clauses' ), 10 );
          } );
        }
        
        if( ! isset( $query['price_filter'] ) ) {
          $min_price = isset( $this->query->awf['min_price'] ) ? floatval( wp_unslash( $this->query->awf['min_price'] ) ) : 0;
          $max_price = isset( $this->query->awf['max_price'] ) ? floatval( wp_unslash( $this->query->awf['max_price'] ) ) : PHP_INT_MAX;

          if ( wc_tax_enabled() && 'incl' === get_option( 'woocommerce_tax_display_shop' ) && ! wc_prices_include_tax() ) {
            $tax_rates = WC_Tax::get_rates( '' );

            if ( $tax_rates ) {
              $min_price -= WC_Tax::get_tax_total( WC_Tax::calc_inclusive_tax( $min_price, $tax_rates ) );
              $max_price -= WC_Tax::get_tax_total( WC_Tax::calc_inclusive_tax( $max_price, $tax_rates ) );
            }
          }

          $query['price_filter'] = array(
            'key'     => '_price',
            'value'   => array( $min_price, $max_price ),
            'compare' => 'BETWEEN',
            'type'    => 'DECIMAL(10,' . wc_get_price_decimals() . ')',
          );
        }
      }
      
      if( ( isset( $this->query->awf['min_rating'] ) || isset( $this->query->awf['max_rating'] ) ) & ! isset( $query['awf_rating_filter']['awf_rating_filter'] ) ) {
        $range_min = isset( $this->query->awf['min_rating'] ) ? (float) $this->query->awf['min_rating'] : (float) 0.01;
        if( floatval(0) === $range_min ) { $range_min = (float) 0.01; }
        $range_max = isset( $this->query->awf['max_rating'] ) ? (float) $this->query->awf['max_rating'] : (float) 5;
        
        $query['awf_rating_filter'] = array(
          'key' => '_wc_average_rating',
          'value' => array( $range_min, $range_max ),
          'compare' => 'BETWEEN',
          'type' => 'DECIMAL(3,2)',
          'awf_rating_filter' => true,
        );
      }
      
      return $query;
    }
    
    public function set_wc_post__in( $postin ) {
      if( isset( $this->query->awf['onsale'] ) ) {
        $onsale_posts = array_merge( array( 0 ), wc_get_product_ids_on_sale() );
        if( empty( $postin ) ) { $postin = $onsale_posts; }
        else { $postin = array_intersect( $postin, $onsale_posts ); }
      }
      
      return $postin;
    }

    public function set_sc_post__in( &$args ) {
      if ( ! empty( $this->query->awf['search'] ) ) {
        $data_store = WC_Data_Store::load( 'product' );
        $posts = $data_store->search_products( wc_clean( wp_unslash( $this->query->awf['search'] ) ), '', true, true );

        if( ! empty( $args['p'] ) ) {
          $posts = array_intersect( $posts, array( $args['p'] ) );
          unset( $args['p'] );
        }

        if( ! empty( $args['post__in'] ) && is_array( $args['post__in'] ) ) {
          $posts = array_intersect( $posts, $args['post__in'] );
        }

        $posts = array_unique( array_merge( $posts, array( 0 ) ) );
        $args['post__in'] = $posts;
      }

      return;
    }

    public function set_default_visibility( &$tax_query ) {
      $tax_query[] = array(
        'taxonomy'         => 'product_visibility',
        'terms'            => 'exclude-from-catalog',
        'field'            => 'name',
        'operator'         => 'NOT IN',
        'include_children' => false,
      );
    }

    public function set_visibility_instock( &$tax_query ) {
      $tax_query[] = array(
          'taxonomy'         => 'product_visibility',
          'terms'            => array( 'outofstock' ),
          'field'            => 'name',
          'operator'         => 'NOT IN',
          'include_children' => false,
      );
    }

    public function set_visibility_outofstock( &$tax_query ) {
      $tax_query[] = array(
          'taxonomy'         => 'product_visibility',
          'terms'            => array( 'outofstock' ),
          'field'            => 'name',
          'operator'         => 'IN',
          'include_children' => false,
      );
    }
    
    public function set_visibility_featured( &$tax_query ) {
      $tax_query[] = array(
        'taxonomy'         => 'product_visibility',
        'terms'            => 'featured',
        'field'            => 'name',
        'operator'         => 'IN',
        'include_children' => false,
      );
    }
    
    public function wc_query( $query, $wc_query ) { return; }
    public function after_wc_query( $query ) { return; }
    
    public function set_shop_columns() {
      return $this->awf_settings['shop_columns'];
    }

    public function set_products_per_page( $ppp ) {

      if( isset( $this->query->awf['ppp'] ) ) {
        $ppp = $this->query->awf['ppp'] = (int) $this->query->awf['ppp'];
//
      } else if(! empty( $this->awf_settings['ppp_default'] ) ) { 
        $ppp = $this->awf_settings['ppp_default']; 
      }

      return $ppp;
    }

    public function adjust_wc_pagination( $args ) {
      if( ! empty( $this->is_sc_page ) ) {
        $args['base'] = esc_url_raw( add_query_arg( array( 'product-page' => '%#%' ), $this->current_url ) );
      } else {
        $args['base'] = esc_url_raw( add_query_arg( array( 'paged' => '%#%' ), $this->current_url ) );        
      }

      $args['add_args'] = $_GET;
      
      return $args;
    }

    public function add_awf_sc_class( $attrs ) {
      if( empty( $attrs['class'] ) ) { $attrs['class'] = 'awf-sc'; } else { $attrs['class'] .= ' awf-sc'; }

      return $attrs;
    }

    public function insert_sc_ajax_vars( $attrs ) {
      foreach( $attrs as $name => $value ) {
        echo '<input type="hidden" name="' . $name . '" value="' . $value . '" class="awf-sc-var">';
      }
    }

    public function display_shortcode_no_results_message( $attrs ) {
      echo '<p class="woocommerce-info">',
        __( 'No products were found matching your selection.', 'annasta_filters' ),
        '</p>';
    }

    public function redirect_archives() {
      if( is_product_category() && empty( $this->awf_settings['cat_views_on'] ) ) {
        $queried_object = get_queried_object();
        wp_redirect( add_query_arg( $this->tax_var_names['product_cat'], $queried_object->slug, $this->shop_url ) );
        die;
        
      } elseif( is_product_tag() ) {
        $queried_object = get_queried_object();
        wp_redirect( add_query_arg( $this->tax_var_names['product_tag'], $queried_object->slug, $this->shop_url ) );
        die;
      }
    }

    public function enqueue_scripts( $hook ) {
      wp_enqueue_style( 'awf-nouislider', A_W_F_PLUGIN_URL . '/styles/nouislider.min.css', array(), A_W_F::$plugin_version );
      
      if ( 'yes' === get_option( 'awf_pretty_scrollbars' ) ) {
        wp_enqueue_style( 'awf-pretty-scrollbars', A_W_F_PLUGIN_URL . '/styles/perfect-scrollbar.css' );
        wp_enqueue_script( 'awf-pretty-scrollbars', A_W_F_PLUGIN_URL . '/code/js/perfect-scrollbar.min.js', array(), A_W_F::$plugin_version );
      }

      wp_enqueue_style( 'awf', A_W_F_PLUGIN_URL . '/styles/awf.css', false, A_W_F::$plugin_version );
      
      $uploads_dir = wp_upload_dir();
      if( file_exists( $uploads_dir['basedir'] . '/annasta-filters/style-options.css' ) ) {
        $style_options_url = $uploads_dir['baseurl'] . '/annasta-filters/style-options.css';
        if ( is_ssl() ) { $style_options_url = str_replace( 'http://', 'https://', $style_options_url ); }
      
        wp_enqueue_style( 'awf-style-options', $style_options_url, array( 'awf' ), A_W_F::$plugin_version );
      }

      wp_enqueue_script( 'awf-nouislider', A_W_F_PLUGIN_URL . '/code/js/nouislider.min.js' );
      wp_enqueue_script( 'awf', A_W_F_PLUGIN_URL . '/code/js/awf.js', array( 'jquery', 'jquery-ui-core', 'jquery-ui-sortable', 'awf-nouislider' ), A_W_F::$plugin_version );

      wp_localize_script( 'awf', 'awf_data', $this->build_js_data() );
    }

    public function enqueue_premium_scripts( $hook ) {
      wp_enqueue_script( 'awf-premium', A_W_F_PLUGIN_URL . '/code/js/awf-premium.js', array( 'jquery', 'jquery-ui-core', 'jquery-ui-sortable' ), A_W_F::$plugin_version );
    }

    private function build_js_data() {
      $shop_url_pieces = explode( '?', $this->shop_url );
      if( ! isset( $shop_url_pieces[1] ) ) { $shop_url_pieces[1] = ''; }

      $js_data = array( 
        'shop_url' => $shop_url_pieces[0],
        'ajax_url' => admin_url( 'admin-ajax.php' ),
        'query' => $this->filter_on ? $_GET : wp_parse_args( $shop_url_pieces[1] ),
        'redirect_ajax' => ! $this->filter_on,
        'product_counts' => new ArrayObject(),
        'products_wrapper' => get_option( 'awf_products_html_wrapper', '#main' ),
      );
      
      if ( $this->permalinks_on ) {
        $js_data['permalinks'] = 'yes';
        if( $this->filter_on ) {
          if( ! empty( $this->awf_settings['cat_views_on'] ) && isset( $this->query->tax['product_cat'] ) ) {
            
            $js_data['query']['product_cat'] = implode( ',', $this->query->tax['product_cat'] );
          }
        }
        
        if ( ! empty( $this->awf_settings['cat_views_on'] ) ) {
          $js_data['cat_url'] = $this->cat_url_template;
        }
      }
      
      if( false !== $this->is_sc_page ) { $js_data['sc_page'] = $this->is_sc_page; }
      elseif( ! empty( $this->shop_on_frontpage ) ) { $js_data['shop_on_frontpage'] = 'yes'; }

      unset( $js_data['query']['paged'] );

      $js_data['query'] = new ArrayObject( $js_data['query'] );

      return $js_data;
    }

    public function display_shortcode( $parameters ) {
      return $this->get_preset_html( $parameters['preset_id'], $parameters['shortcode_id'] );
    }

    public function display_widget( $preset_id, $parameters ) {
      echo $this->get_preset_html( intval( $preset_id ), $parameters['id'] );
    }

    private function get_preset_html( $preset_id, $caller_id ) {
      if( ! isset( A_W_F::$presets[$preset_id] ) ) return;
      
      if( is_null( $this->page_associations ) ) {
        $this->build_page_associations();

        ksort( $this->query->tax );
        ksort( $this->query->awf );

        array_walk( $this->query->tax, function( &$value, $key ) {
          if( is_array( $value ) ) { sort( $value ); }
        });

        array_walk( $this->query->awf, function( &$value, $key ) {
          if( is_array( $value ) ) { sort( $value ); }
        });

        $awf_for_cache = $this->query->awf;
        unset( $awf_for_cache['orderby'] );
        unset( $awf_for_cache['ppp'] );

        $this->counts_cache_name = 'awf_counts_' . md5( wp_json_encode( $this->query ) );
        $this->counts = get_transient( $this->counts_cache_name );
        if( false === $this->counts ) { $this->counts = array(); }
      }

      $associated = false;
      
      foreach( A_W_F::$presets[$preset_id]['associations'] as $association_id ) {
        if( $this->in_page_associations( $association_id ) ) {
          $associated = true;
          break;
        }
      }
      
      if( ! $associated ) { return; }
      
      $preset_id = apply_filters( 'awf_display_preset_id', $preset_id );
      
      $preset = new A_W_F_preset_frontend( $preset_id, $caller_id );

      return $preset->get_html();
    }

    private function build_page_associations() {

      $this->page_associations = array();

      foreach( $this->query->tax as $taxonomy => $terms ) {
        foreach( $terms as $slug ) {
          if( false !== ( $term = get_term_by( 'slug', $slug, $taxonomy ) ) ) {
            $this->add_associations( $term, $taxonomy );
          }
        }
      }

      if( false !== $this->is_wp_page ) {
        $this->page_associations['wp_page'][0][0] = $this->is_wp_page;
      }

    }

    private function add_associations( $term, $taxonomy ) {

      if( $term->parent > 0 ) {
        if( false !== ( $parent = get_term_by( 'id', $term->parent, $taxonomy ) ) ) {
          $this->add_associations( $parent, $taxonomy );
        }
      }

      if(
        ! isset( $this->page_associations[$taxonomy] )
        || ! isset( $this->page_associations[$taxonomy][$term->parent] )
        || ! in_array( $term->slug, $this->page_associations[$taxonomy][$term->parent] )
      ) {
        $this->page_associations[$taxonomy][$term->parent][] = $term->slug;
      }

      return;
    }

    public function in_page_associations( $association_id ) {

      if(
        ( $association_id === 'all' )
        || ( ( $association_id === 'shop-pages' ) && ( is_shop() || is_product_category() ) )
        || ( ( $association_id === 'cat-pages' ) && is_product_category() )
      ) {
        return true;
      }

      $association = explode( '--', $association_id );

      if( ! isset( $this->page_associations[$association[0]] ) ) { return false; }

      foreach( $this->page_associations[$association[0]] as $term ) {
        if( in_array( $association[1], $term ) ) {
          return true;
        }
      }

      return false;
    }

    public function get_url_query() {

      $url_query = array();

      foreach( $this->query->tax as $var => $value ) {
        $url_query[$this->tax_var_names[$var]] = implode( ',', $value );
      }
      foreach( $this->query->awf as $var => $value ) {
        $url_query[$this->awf_var_names[$var]] = $value;
      }
      
      if( ! empty( $this->shop_on_frontpage ) && empty( $this->is_sc_page )
         && ( ! empty( $this->query->awf['orderby'] ) || ! empty( $this->query->awf['search'] ) )
      ) {
          $url_query['post_type'] = 'product';
      }

      return $url_query;
    }

    public function redirect_single_search_result() {

      if ( 'yes' === get_option( 'awf_redirect_search', false ) ) { return true; }

      return false;
    }

    public function display_no_results_msg( $attrs ) {
      echo '<p class="woocommerce-info">' . esc_html__( 'No products were found matching your selection', 'annasta-filters' ) . '</p>';
    }

    public function adjust_shop_title( $title ) {

      if( isset( $this->query->tax['product_cat'] ) ) {
        $title = $this->cat_names;

      } else {
        if ( is_search() ) {
          $title   = get_the_title( $this->shop_page_id );
        }
      }

      return $title;
    }

    public function adjust_document_title( $title ) {
      /* $title = array( 'title', 'page', 'tagline', 'site' ) */

      if ( is_shop() ) {
        if ( is_search() ) {
          $title['title'] = get_the_title( $this->shop_page_id );
        }

      } else if ( is_product_category() ) {
        $title['title'] = get_the_title( $this->shop_page_id ) . ': ' . $this->cat_names;
      }

      return $title;
    }

    public function adjust_breadcrumbs( $crumbs, $class ) {

      if( ! ( is_shop() || is_product_category() ) ) { return $crumbs; }

      if( $this->filter_on ) {
        $crumbs = array();

        $crumbs[] = array( single_post_title( '', false ), home_url() );
        $crumbs[] = array( get_the_title( $this->shop_page_id ), $this->shop_url );

        if( ! empty( $this->cat_names ) ) {
          $crumbs[] = array( $this->cat_names );
        }
      }

      return $crumbs;
    }

    public function update_counts_cache() {
      if( true === $this->update_counts_cache && ! empty( $this->counts ) ) {
        set_transient( $this->counts_cache_name, $this->counts, DAY_IN_SECONDS * 30 );
      }
    }
    
    private final function __clone() {}
    private final function __wakeup() {}
    public static function get_instance() {
      if( is_null( self::$instance ) ) {
        self::$instance = new self();
      }
      return self::$instance;
    }

  }
}

?>