php - Insert a post type every x posts in custom loop -

i hoping me problem.

i'm trying make loop in wordpress 2 different post types ('product' , 'outfits')

the code below working fine, outputs list of 2 post types ordered newest older.

    $loop = new wp_query( array(                  'post_type' => array( 'product', 'outfits' ),                 'posts_per_page' => 15               ) );              $counter = 0;             ?>             <?php if ( $loop->have_posts() ) { while ( $loop->have_posts() ) { $loop->the_post();             $counter++; ?>             <?php $loop->is_home = false; ?>             <?php                 $large_image_url = wp_get_attachment_image_src( get_post_thumbnail_id($post->id), 'large');                 $titulo = get_the_title();                 $content = apply_filters ('the_content', $post->post_content); ?>               <div class="caja-<?php echo $counter; ?>">                  <?php if ( $post->post_type == "product" ) {                                 //some stuff                 <?php } else {                      //some stuff                 } ?>              </div>             <?php } } wp_reset_postdata(); 

what insert product post type after x number of outfits.

i trying merge similar solution i've found in other question no luck. i'm not php expert appreciated

    <?php     $args = array('post_type'=>'post', 'posts_per_page'=>9, 'category_name'=>'news');     $posts = get_posts($args);      $args = array('post_type'=>'testimonials', 'posts_per_page'=>3);     $testimonials = get_posts($args);     // see how many of regular posts got //    $post_count = count($posts);    // see how many testimonials got //    $testimonial_count = count($testimonials);    // add them total result count //    $total_count = $post_count + $testimonial_count;     // loop through total number of results //    for($i = 1; $i <= $total_count; $i++){     // assuming want show 1 testimonial every third post //    if($i % 3 == 0){    // means you're on third post, show testimonial //     setup_postdata($testimonials[$i]);    }    else{     /** show regular post */    setup_postdata($posts[$i]);    }   /** , handle output */   ?><h1><?php the_title();?></h1><?php   } ?> 

$x = 3; $products = get_posts(array(     'post_type' => 'product',     'posts_per_page' => -1 ));  $outfits = get_posts(array(     'post_type' => 'outfit',     'posts_per_page' => -1 ));  foreach ($outfits $num => $outfit) {     if ( ($num+1) % $x == 0) {         if (isset($products[($num+1)/$x - 1])) {             array_splice( $outfits, $num, 0, array($products[($num+1)/$x - 1]) );             }     } }  foreach ($outfits $outfit) {     $posts_id[] = $outfit->id; }  $query = new wp_query(array(     'post_type' => array('outfit', 'product'),     'post__in' => $posts_id,     'posts_per_page' => 15,     'orderby' => 'post__in' ));