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<?php 

class post_to_pdf {

    public $content;
    public $title;
    public $down;

    function __construct() {
        
    }
    
    //retrieve data
    public function get_post_contents($down="yes", $post_id) {
        echo "started";
        global $post;
        global $wpdb;
        $this->down = $down;
        $str = get_post_field('post_content', $post_id);
        $str = preg_replace('/\[crea_pdf_btn.*?\]/', '', $str);
        $this->content = do_shortcode($str);
        $this->title = get_the_title($post_id);
        $this->create_pdf();
        echo $this->title." - ".$this->content;
    } 

    
    //create PDF
    function create_pdf() {
        
        ob_clean();
        include("mpdf/mpdf.php");
        $mpdf = new mPDF();
        $mpdf->SetDisplayMode('fullpage');
        //$stylesheet = file_get_contents('mpdf/styleCorsiPdf.css');
        $mpdf->WriteHTML($this->content);
        if ($this->down == "no") {
            $mpdf->Output();
        } elseif ($this->down == "yes") {
            $pdfNameFinal = $this->title . ".pdf";
            $mpdf->Output($pdfNameFinal, 'D');
        }
        
    }
    
    
}

$ptpdf = new post_to_pdf();


// BUTTON SHORTCODE
function crea_pdf_btn($atts) {
    $shortcode_atts = (shortcode_atts(array(
      'download' => "yes",
    ), $atts));
    $down = $shortcode_atts[ 'download' ];
	$pdf_btn = '<div>
                <form action="'.get_theme_root_uri().'/woptimizr/post_to_pdf/index.php" method="post" id="ptpdf_form" >
                <input type="hidden" name="ptpdf_down" value="'.$down.'">
                <input type="hidden" name="ptpdf_id" value="'.get_the_ID().'">
                <div class="btn btn-sm btn-danger download_pdf">download PDF <i class="fa fa-file-pdf-o mar-lft"></i></div>
                </form>
                </div>'; 
	return $pdf_btn;
}
add_shortcode('crea_pdf_btn','crea_pdf_btn');


// ENQUEUE JS
wp_enqueue_script( 'post-to-pdf-js', get_theme_root_uri().'/woptimizr/post_to_pdf/post_to_pdf.js' );

?>

<?php
require_once( '../../../../wp-load.php' );

if (isset($_POST['ptpdf_down']) && isset($_POST['ptpdf_id'])) {
    $ptpdf_down = $_POST['ptpdf_down'];
    $ptpdf_id = $_POST['ptpdf_id'];

    $ptpdf->get_post_contents($ptpdf_down,$ptpdf_id);
} else {
    header('Location: ' . $_SERVER['HTTP_REFERER']);
}

?>