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/**
 * Search by SKU or ID for products. Adapted from code by BenIrvin (Admin Search by ID)
 */
if (is_admin()) :
	add_action( 'parse_request', 'jigoshop_admin_product_search' );
	add_filter( 'get_search_query', 'jigoshop_admin_product_search_label' );
endif;

function jigoshop_admin_product_search( $wp ) {
	global $pagenow, $wpdb;
	
	if( 'edit.php' != $pagenow )
		return false;

	if( ! isset( $wp->query_vars['s'] ) )
		return false;

	if ( ($wp->query_vars['post_type'] == 'product' || $wp->query_vars['post_type'] == 'shop_order') ) {

		if ( 'ID:' == substr( $wp->query_vars['s'], 0, 3 )) {

			$id = absint( substr( $wp->query_vars['s'], 3 ) );
				
			if( ! $id )
				return false; 
			
			unset( $wp->query_vars['s'] );
			$wp->query_vars['p'] = $id;
		}
		elseif( $wp->query_vars['post_type'] == 'product' && 'SKU:' == substr( $wp->query_vars['s'], 0, 4 ) ) {
				
			$sku = trim( substr( $wp->query_vars['s'], 4 ) );
				
			if( ! $sku )
				return false; 
			
			$id = $wpdb->get_var('SELECT post_id FROM '.$wpdb->postmeta.' WHERE meta_key="sku" AND meta_value LIKE "%'.$sku.'%";');
			
			if( ! $id )
				return false; 

			unset( $wp->query_vars['s'] );
			$wp->query_vars['p'] = $id;
			$wp->query_vars['sku'] = $sku;

		}
		elseif( $wp->query_vars['post_type'] == 'shop_order' && 'PID:' == substr( $wp->query_vars['s'], 0, 4 ) ) {

			$id = absint( substr( $wp->query_vars['s'], 4 ) );
			$id_length = strlen($id);

			// Get candidate orders
			$meta_value_check = "'%s:2:\"id\";s:$id_length:\"$id\"%'";
			$sql = "SELECT post_id, meta_value FROM {$wpdb->postmeta}
			        WHERE meta_key = 'order_items' AND meta_value LIKE $meta_value_check ";
			$results = $wpdb->get_results($sql);

			// Verify orders contain this product id
			$ids = array();
			foreach ( $results as $result ) {
				$items = unserialize($result->meta_value);
				foreach ( $items as $item ) {
					if ( $item['id'] == $id ) {
						$ids[] = $result->post_id;
						break;
					}
				}
			}

			if ( count($ids) === 0 )
				return false;
		
			// Set search parameters
			unset( $wp->query_vars['s'] );
			$wp->query_vars['post__in'] = $ids;
			$wp->query_vars['order_product_id'] = $id;

		}
	}

}

function jigoshop_admin_product_search_label($query) {
	global $pagenow, $typenow, $wp;

	if ( 'edit.php' != $pagenow ) 
		return $query;

	if ( $typenow == 'product' || $typenow == 'shop_order' ) {
	
		$s = get_query_var( 's' );
		if ( $s )
			return $query;
		
		$sku = get_query_var( 'sku' );
		if($sku) {
			$post_type = get_post_type_object($wp->query_vars['post_type']);
			return sprintf(__("[%s with SKU of %s]", 'jigoshop'), $post_type->labels->singular_name, $sku);
		}
		
		$p = get_query_var( 'p' );
		if ($p) {
			$post_type = get_post_type_object($wp->query_vars['post_type']);
			return sprintf(__("[%s with ID of %d]", 'jigoshop'), $post_type->labels->singular_name, $p);
		}

		$order_id = get_query_var( 'order_product_id' );
		if (get_query_var( 'post__in' )) {
			$post_type = get_post_type_object($wp->query_vars['post_type']);
			return sprintf(__("[%s with product ID of %d]", 'jigoshop'), $post_type->labels->singular_name, $order_id);
		}
	}
	
	return $query;
}