<?php
/**
* Get cURL callback function for CURLOPT_WRITEFUNCTION
*
* @param string $charset to extract from the downloaded page (reference)
* @param string $title to extract from the downloaded page (reference)
* @param string $curlGetInfo Optionnaly overrides curl_getinfo function
*
* @return Closure
*/
function get_curl_download_callback(&$charset, &$title, $curlGetInfo = 'curl_getinfo')
{
$isRedirected = false;
/**
* cURL callback function for CURLOPT_WRITEFUNCTION (called during the download).
*
* While downloading the remote page, we check that the HTTP code is 200 and content type is 'html/text'
* Then we extract the title and the charset and stop the download when it's done.
*
* @param resource $ch cURL resource
* @param string $data chunk of data being downloaded
*
* @return int|bool length of $data or false if we need to stop the download
*/
return function(&$ch, $data) use ($curlGetInfo, &$charset, &$title, &$isRedirected) {
$responseCode = $curlGetInfo($ch, CURLINFO_RESPONSE_CODE);
if (!empty($responseCode) && in_array($responseCode, [301, 302])) {
$isRedirected = true;
return strlen($data);
}
if (!empty($responseCode) && $responseCode !== 200) {
return false;
}
// After a redirection, the content type will keep the previous request value
// until it finds the next content-type header.
if (! $isRedirected || strpos(strtolower($data), 'content-type') !== false) {
$contentType = $curlGetInfo($ch, CURLINFO_CONTENT_TYPE);
}
if (!empty($contentType) && strpos($contentType, 'text/html') === false) {
return false;
}
if (!empty($contentType) && empty($charset)) {
$charset = header_extract_charset($contentType);
}
if (empty($charset)) {
$charset = html_extract_charset($data);
}
if (empty($title)) {
$title = html_extract_title($data);
}
// We got everything we want, stop the download.
if (!empty($responseCode) && !empty($contentType) && !empty($charset) && !empty($title)) {
return false;
}
return strlen($data);
};
}
/**
* Extract title from an HTML document.
*
* @param string $html HTML content where to look for a title.
*
* @return bool|string Extracted title if found, false otherwise.
*/
function html_extract_title($html)
{
if (preg_match('!<title.*?>(.*?)</title>!is', $html, $matches)) {
return trim(str_replace("\n", '', $matches[1]));
}
return false;
}
/**
* Extract charset from HTTP header if it's defined.
*
* @param string $header HTTP header Content-Type line.
*
* @return bool|string Charset string if found (lowercase), false otherwise.
*/
function header_extract_charset($header)
{
preg_match('/charset="?([^; ]+)/i', $header, $match);
if (! empty($match[1])) {
return strtolower(trim($match[1]));
}
return false;
}
/**
* Extract charset HTML content (tag <meta charset>).
*
* @param string $html HTML content where to look for charset.
*
* @return bool|string Charset string if found, false otherwise.
*/
function html_extract_charset($html)
{
// Get encoding specified in HTML header.
preg_match('#<meta .*charset=["\']?([^";\'>/]+)["\']? */?>#Usi', $html, $enc);
if (!empty($enc[1])) {
return strtolower($enc[1]);
}
return false;
}
/**
* Count private links in given linklist.
*
* @param array|Countable $links Linklist.
*
* @return int Number of private links.
*/
function count_private($links)
{
$cpt = 0;
foreach ($links as $link) {
if ($link['private']) {
$cpt += 1;
}
}
return $cpt;
}
/**
* In a string, converts URLs to clickable links.
*
* @param string $text input string.
* @param string $redirector if a redirector is set, use it to gerenate links.
* @param bool $urlEncode Use `urlencode()` on the URL after the redirector or not.
*
* @return string returns $text with all links converted to HTML links.
*
* @see Function inspired from http://www.php.net/manual/en/function.preg-replace.php#85722
*/
function text2clickable($text, $redirector = '', $urlEncode = true)
{
$regex = '!(((?:https?|ftp|file)://|apt:|magnet:)\S+[a-z0-9\(\)]/?)!si';
if (empty($redirector)) {
return preg_replace($regex, '<a href="$1">$1</a>', $text);
}
// Redirector is set, urlencode the final URL.
return preg_replace_callback(
$regex,
function ($matches) use ($redirector, $urlEncode) {
$url = $urlEncode ? urlencode($matches[1]) : $matches[1];
return '<a href="' . $redirector . $url .'">'. $matches[1] .'</a>';
},
$text
);
}
/**
* Auto-link hashtags.
*
* @param string $description Given description.
* @param string $indexUrl Root URL.
*
* @return string Description with auto-linked hashtags.
*/
function hashtag_autolink($description, $indexUrl = '')
{
/*
* To support unicode: http://stackoverflow.com/a/35498078/1484919
* \p{Pc} - to match underscore
* \p{N} - numeric character in any script
* \p{L} - letter from any language
* \p{Mn} - any non marking space (accents, umlauts, etc)
*/
$regex = '/(^|\s)#([\p{Pc}\p{N}\p{L}\p{Mn}]+)/mui';
$replacement = '$1<a href="'. $indexUrl .'?addtag=$2" title="Hashtag $2">#$2</a>';
return preg_replace($regex, $replacement, $description);
}
/**
* This function inserts where relevant so that multiple spaces are properly displayed in HTML
* even in the absence of <pre> (This is used in description to keep text formatting).
*
* @param string $text input text.
*
* @return string formatted text.
*/
function space2nbsp($text)
{
return preg_replace('/(^| ) /m', '$1 ', $text);
}
/**
* Format Shaarli's description
*
* @param string $description shaare's description.
* @param string $redirector if a redirector is set, use it to gerenate links.
* @param bool $urlEncode Use `urlencode()` on the URL after the redirector or not.
* @param string $indexUrl URL to Shaarli's index.
* @return string formatted description.
*/
function format_description($description, $redirector = '', $urlEncode = true, $indexUrl = '') {
return nl2br(space2nbsp(hashtag_autolink(text2clickable($description, $redirector, $urlEncode), $indexUrl)));
}
/**
* Generate a small hash for a link.
*
* @param DateTime $date Link creation date.
* @param int $id Link ID.
*
* @return string the small hash generated from link data.
*/
function link_small_hash($date, $id)
{
return smallHash($date->format(LinkDB::LINK_DATE_FORMAT) . $id);
}
