Adjust copyrights years
<?php
/**
* SeekQuarry/Yioop --
* Open Source Pure PHP Search Engine, Crawler, and Indexer
*
* Copyright (C) 2009 - 2023 Chris Pollett chris@pollett.org
*
* LICENSE:
*
* 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 <https://www.gnu.org/licenses/>.
*
* END LICENSE
*
* @author Chris Pollett chris@pollett.org
* @license https://www.gnu.org/licenses/ GPL3
* @link https://www.seekquarry.com/
* @copyright 2009 - 2023
* @filesource
*/
namespace seekquarry\yioop\library\processors;
/**
* Used to create crawl summary information
* for PPT files
*
* @author Chris Pollett
*/
class PptProcessor extends TextProcessor
{
const PPT_IGNORING = 0;
const ZEROONE_IGNORING = 1;
const ZEROTWO_IGNORING = 2;
const FIRST_CHAR_TEXT_SEG = 3;
const READ_LEN_TEXT_SEG = 4;
const SCAN_TEXT_SEG = 5;
const ALWAYS_IGNORE = 6;
/**
* Set-ups the any indexing plugins associated with this page
* processor
*
* @param array $plugins an array of indexing plugins which might
* do further processing on the data handles by this page
* processor
* @param int $max_description_len maximal length of a page summary
* @param int $max_links_to_extract maximum number of links to extract
* from a single document
* @param string $summarizer_option CRAWL_CONSTANT specifying what kind
* of summarizer to use self::BASIC_SUMMARIZER,
* self::GRAPH_BASED_SUMMARIZER and self::CENTROID_SUMMARIZER
* self::CENTROID_SUMMARIZER
*/
public function __construct($plugins = [], $max_description_len = null,
$max_links_to_extract = null,
$summarizer_option = self::BASIC_SUMMARIZER)
{
parent::__construct($plugins, $max_description_len,
$max_links_to_extract, $summarizer_option);
/** Register File Types We Handle*/
self::$indexed_file_types[] = "ppt";
self::$mime_processor["application/vnd.ms-powerpoint"] = "PptProcessor";
}
/**
* Computes a summary based on a string of a binary Powerpoint document
* (as opposed to the modern xml powerpoint format).
*
* Text is extracted from the Powerpoint document using a crude finite
* state machine that was developed by looking at a few Powerpoint
* documents in a Hex editor. Then the TextProcessor:: process() method
* is used to make a summary
*
* @param string $page string of a Powerpoint document
* @param string $url location the document came from, not used by
* TextProcessor at this point. Some of its subclasses override
* this method and use url to produce complete links for
* relative links within a document
*
* @return array a summary of (title, description,links, and content) of
* the information in $page
*/
public function process($page, $url)
{
$text = "";
if (is_string($page)) {
$text_objects = [];
$cur_id = 0;
$state = self::PPT_IGNORING;
$cur_char_pos = 0;
$len = strlen($page);
while ($cur_char_pos < $len) {
$ascii = ord($page[$cur_char_pos]);
switch ($state) {
case self::PPT_IGNORING:
if ($ascii == 0) {
$state = self::ZEROONE_IGNORING;
}
break;
case self::ZEROONE_IGNORING:
if ($ascii == 0) {
$state = self::ZEROTWO_IGNORING;
} else {
$state = self::PPT_IGNORING;
}
break;
case self::ZEROTWO_IGNORING:
if ($ascii == 168) {
$state = self::FIRST_CHAR_TEXT_SEG;
} else if ($ascii != 0) {
$state = self::PPT_IGNORING;
}
break;
case self::FIRST_CHAR_TEXT_SEG:
if ($ascii == 15) {
$state = self::READ_LEN_TEXT_SEG;
$text_len = 0;
$text_len_pos = 0;
} else {
$state = self::PPT_IGNORING;
}
break;
case self::READ_LEN_TEXT_SEG:
if ($text_len_pos < 4) {
$text_len += ($ascii << ($text_len_pos * 8));
$text_len_pos++;
} else {
$state = self::SCAN_TEXT_SEG;
$scan_text_pos = 0;
$out_text = chr($ascii);
}
break;
case self::SCAN_TEXT_SEG:
if (strpos($out_text,
"lick to edit Master title style") > 0) {
$state = self::ALWAYS_IGNORE;
} else if ($scan_text_pos < $text_len) {
if (($ascii >= 32 && $ascii <= 126) ||
$ascii == 10) {
$out_text .= chr($ascii);
$scan_text_pos++;
}
} else {
$text_objects[$cur_id] = $out_text;
$cur_id++;
$state = self::PPT_IGNORING;
}
break;
case self::ALWAYS_IGNORE:
break;
}
$cur_char_pos++;
}
$text = implode("\n", $text_objects);
}
if ($text == "") {
$text = $url;
}
$summary = parent::process($text, $url);
return $summary;
}
}