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/*------------------------------------------------------------------------*\
	Filter Content: Add our own html_blocks/ads in between blocks
\*------------------------------------------------------------------------*/
add_filter( 'the_content', 'pd_post_list_content_filter', 1 );
function pd_post_list_content_filter( $content ) {

    /**
     * ! Filter if not front end and not list post then return
     * * https://stackoverflow.com/questions/52306320/php-insert-html-after-the-nth-occurrence-of-a-p-tag
     */

    error_log( print_r( "BEFORE", true ) );
    error_log( print_r( $content, true ) );
    global $post;

    if ( has_blocks( $post->post_content ) ) {
        
        echo str_replace_n_after("</p>", "<a href='https://www.google.com/'>test</a>",$html , 2);
        
        $blocks = parse_blocks( $post->post_content );

        // array_splice( $blocks, 2, 0, array('<!-- wp:html --><div class="spomething"></div><!-- /wp:html -->') );

        // $content = "";
        // foreach ($blocks as $block) {
            // error_log( print_r( $block, true ) );
            // $content .= $block;
            // if( !empty($block['blockName']) ){
            //     $counter_blocks++;
            // }
        // }

        // error_log( print_r( "this post has " . $counter_blocks . " blocks.", true ) );
        if ( $blocks[0]['blockName'] === 'core/heading' ) {
        }
    }

    // error_log( print_r( "AFTER", true ) );
    // error_log( print_r( $content, true ) );

    // Returns the content.
    return $content;

}

function str_replace_n_after($search, $replace, $subject, $occurrence) {
    $search = preg_quote($search,'/');
    return preg_replace("/((?:.*?$search){".$occurrence."})/s", "$1$replace", $subject);
}