PDFMerger.php

<?php
/**
 *  PDFMerger created by Jarrod Nettles December 2009
 *  jarrod@squarecrow.com
 *  https://pdfmerger.codeplex.com/
 *  https://github.com/rguedes/PDFMerger
 *  https://github.com/myokyawhtun/PDFMerger
 *
 *  v1.0.3+
 *
 * Class for easily merging PDFs (or specific pages of PDFs) together into one. Output to a file, browser, download, or return as a string.
 * Unfortunately, this class does not preserve many of the enhancements your original PDF might contain. It treats
 * your PDF page as an image and then concatenates them all together.
 *
 * Note that your PDFs are merged in the order that you provide them using the addPDF function, same as the pages.
 * If you put pages 12-14 before 1-5 then 12-15 will be placed first in the output.
 *
 *
 * Uses FPDI 1.6.1 from Setasign
 * Uses FPDF 1.8.1 by Olivier Plathey with FPDF_TPL extension 1.1.3 by Setasign
 *
 * Both of these packages are free and open source software, bundled with this class for ease of use.
 * They are not modified in any way. PDFMerger has all the limitations of the FPDI package - essentially, it cannot import dynamic content
 * such as form fields, links or page annotations (anything not a part of the page content stream).
 *
 * Sample usage
 *
 <?php
 include 'PDFMerger.php';
 $pdf = new PDFMerger;
 $pdf->addPDF('samplepdfs/one.pdf', '1, 3, 4')
     ->addPDF('samplepdfs/two.pdf', '1-2')
     ->addPDF('samplepdfs/three.pdf', 'all')
     ->merge('file', 'samplepdfs/TEST2.pdf');

 // REPLACE 'file' WITH 'browser', 'download', 'string', or 'file' for output options
 // You do not need to give a file path for browser, string, or download - just the name.

 ?>
 */
class PDFMerger

{
    private $_files;   //['form.pdf']  ["1,2,4, 5-19, 22-"]
    private $_fpdi;
    public $_curpages; // Number of pages in last added file

    /**
     * Merge PDFs.
     * @return void
     */
    public

    function __construct()
    {
        if (!class_exists("FPDF"))
        {
            require_once ('fpdf/fpdf.php');
        }

        if (!class_exists("FPDI"))
        {
            require_once ('fpdi/fpdi.php');
        }
    }

    /**
     * Add a PDF for inclusion in the merge with a valid file path. Pages should be formatted: 1,3,6, 12-16.
     * @param $filepath
     * @param $pages
     * @return void
     * @throws exception
     */
    public

    function addPDF($filepath, $pages = 'all')
    {
        if (file_exists($filepath))
        {
            if (strtolower($pages) != 'all')
            {
                $fpdi1 = new FPDI;
                $count = $fpdi1->setSourceFile($filepath);
                $this->_curpages = $count;
                $pages = $this->_rewritepages($pages, $count);
                unset($fpdi1);
            }

            $this->_files[] = array(
                $filepath,
                $pages
            );
        }
        else
        {
            throw new exception("Could not locate PDF on '$filepath'");
        }

        return $this;
    }

    /**
     * Merges your provided PDFs and outputs to specified location.
     * @param $outputmode
     * @param $outputname
     * @return PDF
     * @throws exception
     */
    public

    function merge($outputmode = 'browser', $outputpath = 'newfile.pdf')
    {
        if (!isset($this->_files) || !is_array($this->_files)):
            throw new exception("No PDFs to merge.");
        endif;
        $fpdi = new FPDI;

        // merger operations

        foreach($this->_files as $fkey => $file)
        {
            $filename = $file[0];
            $filepages = $file[1];
            $count = $fpdi->setSourceFile($filename);
            $this->_files[$fkey][2] = $count;

            // add the pages

            if ($filepages == 'all')
            {
                for ($i = 1; $i <= $count; $i++)
                {
                    $template = $fpdi->importPage($i);
                    $size = $fpdi->getTemplateSize($template);
                    $orientation = ($size['h'] > $size['w']) ? 'P' : 'L';
                    $fpdi->AddPage($orientation, array(
                        $size['w'],
                        $size['h']
                    ));
                    $fpdi->useTemplate($template);
                }
            }
            else
            {
                foreach($filepages as $page)
                {
                    if (!$template = $fpdi->importPage($page)):
                        throw new exception("Could not load page '$page' in PDF '$filename'. Check that the page exists.");
                    endif;
                    $size = $fpdi->getTemplateSize($template);
                    $orientation = ($size['h'] > $size['w']) ? 'P' : 'L';
                    $fpdi->AddPage($orientation, array(
                        $size['w'],
                        $size['h']
                    ));
                    $fpdi->useTemplate($template);
                }
            }
        }

        // output operations

        $mode = $this->_switchmode($outputmode);
        if ($mode == 'S')
        {
            return $fpdi->Output($outputpath, 'S');
        }
        else
        {
            if ($fpdi->Output($outputpath, $mode) == '')
            {
                return true;
            }
            else
            {
                throw new exception("Error outputting PDF to '$outputmode'.");
                return false;
            }
        }
    }

    /**
     * FPDI uses single characters for specifying the output location.
     * Change our more descriptive string into proper format.
     * @param $mode
     * @return Character
     * executed at fpdf::Output()
     */
    private
    function _switchmode($mode)
    {
        switch (strtolower($mode))
        {
        case 'download':
            return 'D'; // Download
            break;

        case 'browser':
            return 'I'; // Inline In Browser
            break;

        case 'file':
            return 'F'; // Save As Local File
            break;

        case 'string':
            return 'S'; // As String
            break;

        default:
            return 'I';
            break;
        }
    }

    /**
     * Takes our provided pages in the form of 1,3,4,16-50,70- and creates an array of all pages
     * @param $pages
     * @param $numpages is total number of pages in file
     * @return array
     * @throws exception
     */
    private
    function _rewritepages($pages, $numpages = 0)
    {
        $pages = str_replace(' ', '', $pages);
        $part = explode(',', $pages);

        // parse hyphens

        foreach($part as $i)
        {
            $ind = explode('-', $i);
            if (count($ind) == 2)
            {
                $x = $ind[0]; //start page
                $y = $ind[1]; //end page
                if (strlen(trim($y)) == 0) $y = $numpages;
                if ($x > $y):
                    throw new exception("Starting page, '$x' is greater than ending page '$y'.");
                    return false;
                endif;

                // add middle pages

                while ($x <= $y):
                    $newpages[] = (int)$x;
                    $x++;
                endwhile;
            }
            else
            {
                $newpages[] = (int)$ind[0];
            }
        }

        return $newpages;
    }
}