<?php

// This file is part of Moodle - http://moodle.org/
//
// Moodle is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// Moodle is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.

/**
 * pdflib.php - Moodle PDF library
 *
 * We currently use the TCPDF library by Nicola Asuni.
 *
 * The default location for fonts that are included with TCPDF is
 * lib/tcpdf/fonts/. If PDF_CUSTOM_FONT_PATH exists, this directory
 * will be used instead of lib/tcpdf/fonts/. If there is only one font
 * present in PDF_CUSTOM_FONT_PATH, the font is used as the default
 * font.
 *
 * See lib/tcpdf/fonts/README for details on how to convert fonts for use
 * with TCPDF.
 *
 * Example usage:
 * <code>
 *    $doc = new pdf;
 *    $doc->setPrintHeader(false);
 *    $doc->setPrintFooter(false);
 *    $doc->AddPage();
 *    $doc->Write(5, 'Hello World!');
 *    $doc->Output();
 * </code>
 *
 * @package     moodlecore
 * @copyright   Vy-Shane Sin Fat
 * @license     http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
 */

defined('MOODLE_INTERNAL') || die();

/** defines the site-specific location of fonts */
define('PDF_CUSTOM_FONT_PATH', $CFG->dataroot.'/fonts/');

/** default font to be used if there are more of them available */
define('PDF_DEFAULT_FONT', 'FreeSerif');

/** tell tcpdf it is configured here instead of in its own config file */
define('K_TCPDF_EXTERNAL_CONFIG', 1);

// The configuration constants needed by tcpdf follow

/** tcpdf installation path */
define('K_PATH_MAIN', $CFG->dirroot.'/lib/tcpdf/');

/** URL path to tcpdf installation folder */
define('K_PATH_URL', $CFG->wwwroot . '/lib/tcpdf/');

/** path for PDF fonts */
define('K_PATH_FONTS', K_PATH_MAIN . 'fonts/');

/** cache directory for temporary files (full path) */
define('K_PATH_CACHE', $CFG->cachedir . '/tcpdf/');

/** images directory */
define('K_PATH_IMAGES', $CFG->dirroot . '/');

/** blank image */
define('K_BLANK_IMAGE', K_PATH_IMAGES . '/pix/spacer.gif');

/** height of cell repect font height */
define('K_CELL_HEIGHT_RATIO', 1.25);

/** reduction factor for small font */
define('K_SMALL_RATIO', 2/3);

/** Throw exceptions from errors so they can be caught and recovered from. */
define('K_TCPDF_THROW_EXCEPTION_ERROR', true);

require_once(dirname(__FILE__).'/tcpdf/tcpdf.php');

/**
 * Wrapper class that extends TCPDF (lib/tcpdf/tcpdf.php).
 * Moodle customisations are done here.
 *
 * @package     moodlecore
 * @copyright   Vy-Shane Sin Fat
 * @license     http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
 */
class pdf extends TCPDF {

    /**
     * Class constructor
     *
     * See the parent class documentation for the parameters info.
     */
    public function __construct($orientation='P', $unit='mm', $format='A4', $unicode=true, $encoding='UTF-8') {
        make_cache_directory('tcpdf');

        parent::__construct($orientation, $unit, $format, $unicode, $encoding);

        if (is_dir(PDF_CUSTOM_FONT_PATH)) {
            $fontfiles = $this->_getfontfiles(PDF_CUSTOM_FONT_PATH);

            if (count($fontfiles) == 1) {
                $autofontname = substr($fontfiles[0], 0, -4);
                $this->AddFont($autofontname, '', $autofontname.'.php');
                $this->SetFont($autofontname);
            } else if (count($fontfiles == 0)) {
                $this->SetFont(PDF_DEFAULT_FONT);
            }
        } else {
            $this->SetFont(PDF_DEFAULT_FONT);
        }

        // theses replace the tcpdf's config/lang/ definitions
        $this->l['w_page']          = get_string('page');
        $this->l['a_meta_language'] = current_language();
        $this->l['a_meta_charset']  = 'UTF-8';
        $this->l['a_meta_dir']      = get_string('thisdirection', 'langconfig');
    }

    /**
     * Send the document to a given destination: string, local file or browser.
     * In the last case, the plug-in may be used (if present) or a download ("Save as" dialog box) may be forced.<br />
     * The method first calls Close() if necessary to terminate the document.
     * @param $name (string) The name of the file when saved. Note that special characters are removed and blanks characters are replaced with the underscore character.
     * @param $dest (string) Destination where to send the document. It can take one of the following values:<ul><li>I: send the file inline to the browser (default). The plug-in is used if available. The name given by name is used when one selects the "Save as" option on the link generating the PDF.</li><li>D: send to the browser and force a file download with the name given by name.</li><li>F: save to a local server file with the name given by name.</li><li>S: return the document as a string (name is ignored).</li><li>FI: equivalent to F + I option</li><li>FD: equivalent to F + D option</li><li>E: return the document as base64 mime multi-part email attachment (RFC 2045)</li></ul>
     * @public
     * @since 1.0
     * @see Close()
     */
    public function Output($name='doc.pdf', $dest='I') {
        $olddebug = error_reporting(0);
        $result  = parent::output($name, $dest);
        error_reporting($olddebug);
        return $result;
    }

    /**
     * Return fonts path
     * Overriding TCPDF::_getfontpath()
     *
     * @global object
     */
    protected function _getfontpath() {
        global $CFG;

        if (is_dir(PDF_CUSTOM_FONT_PATH)
                    && count($this->_getfontfiles(PDF_CUSTOM_FONT_PATH)) > 0) {
            $fontpath = PDF_CUSTOM_FONT_PATH;
        } else {
            $fontpath = K_PATH_FONTS;
        }
        return $fontpath;
    }

    /**
     * Get the .php files for the fonts
     */
    protected function _getfontfiles($fontdir) {
        $dirlist = get_directory_list($fontdir);
        $fontfiles = array();

        foreach ($dirlist as $file) {
            if (substr($file, -4) == '.php') {
                array_push($fontfiles, $file);
            }
        }
        return $fontfiles;
    }

}
