<?php
/**
 * webtrees: online genealogy
 * Copyright (C) 2018 webtrees development team
 * This program 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.
 * This program 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 this program. If not, see <http://www.gnu.org/licenses/>.
 */
declare(strict_types=1);

namespace Fisharebest\Webtrees\Report;

use Fisharebest\Webtrees\Tree;

/**
 * Class ReportParserBase
 */
class ReportParserBase
{
    /** @var resource The XML parser */
    protected $xml_parser;

    /** @var string Text contents of tags */
    protected $text = '';

    /**
     * Create a parser for a report
     *
     * @param string $report The XML filename
     */
    public function __construct(string $report)
    {
        $this->xml_parser = xml_parser_create();
        xml_parser_set_option($this->xml_parser, XML_OPTION_CASE_FOLDING, false);
        xml_set_element_handler($this->xml_parser, [
            $this,
            'startElement',
        ], [
            $this,
            'endElement',
        ]);
        xml_set_character_data_handler($this->xml_parser, [
            $this,
            'characterData',
        ]);

        $fp = fopen($report, 'r');
        while (($data = fread($fp, 4096))) {
            if (!xml_parse($this->xml_parser, $data, feof($fp))) {
                throw new \DomainException(sprintf(
                    'XML error: %s at line %d',
                    xml_error_string(xml_get_error_code($this->xml_parser)),
                    xml_get_current_line_number($this->xml_parser)
                ));
            }
        }

        xml_parser_free($this->xml_parser);
    }

    /**
     * XML handler for an opening (or self-closing) tag.
     *
     * @param resource $parser The resource handler for the xml parser
     * @param string   $name   The name of the xml element parsed
     * @param string[] $attrs  An array of key value pairs for the attributes
     *
     * @return void
     */
    protected function startElement($parser, $name, $attrs)
    {
        $method = $name . 'StartHandler';
        if (method_exists($this, $method)) {
            $this->$method($attrs);
        }
    }

    /**
     * XML handler for a closing tag.
     *
     * @param resource $parser the resource handler for the xml parser
     * @param string   $name   the name of the xml element parsed
     *
     * @return void
     */
    protected function endElement($parser, $name)
    {
        $method = $name . 'EndHandler';
        if (method_exists($this, $method)) {
            $this->$method();
        }
    }

    /**
     * XML handler for character data.
     *
     * @param resource $parser The resource handler for the xml parser
     * @param string   $data   The name of the xml element parsed
     *
     * @return void
     */
    protected function characterData($parser, $data)
    {
        $this->text .= $data;
    }
}