Minigalnano/rss.php

<?php
/*============================*/
/* Gallery address definition */
/*============================*/

if (!empty($_SERVER['REQUEST_SCHEME'])) {
    $g_protocol = $_SERVER['REQUEST_SCHEME'];
} elseif (!empty($_SERVER['HTTPS']) && $_SERVER['HTTPS'] == 'on') {
    $g_protocol = 'https';
} else {
    $g_protocol = 'http';
}
$g_host = $_SERVER['HTTP_HOST'];
$g_port = $_SERVER['SERVER_PORT'];
$g_path = dirname($_SERVER['REQUEST_URI']);

// remove default ports
if (($g_protocol == 'https' && $g_port == '443') ||
    ($g_protocol == 'http' && $g_port == '80')) {
    $g_port = '';
} else {
    $g_port = ':' . $g_port;
}

if ($g_path[0] != '/') {
    $g_path = '/' . $g_path;
}

$gallery_link = $g_protocol . '://' . $g_host . $g_port . $g_path;

/*===================*/
/* Functions         */
/*===================*/
# Hardly inspired from here : codes-sources.commentcamarche.net/source/35937-creation-d-une-arborescenceI
# Listing all files of a folder and sub folders. 
function listFiles(&$content, $Folder, $SkipFileExts, $SkipObjects)
{
    $dir = opendir($Folder);
    // Loop on all contained on the folder
    while (false !== ($Current = readdir($dir))) {
        if ($Current !='.' && $Current != '..' && in_array($Current, $SkipObjects) === false) {
            if (is_dir($Folder.'/'.$Current)) {
                ListFiles($content, $Folder . '/' . $Current, $SkipFileExts, $SkipObjects);
            } else {
                $FileExt = strtolower(substr(strrchr($Current, '.'), 1));
                // Should we display this extension ?
                if (in_array($FileExt, $SkipFileExts) === false) {
                    $current_adress = $Folder.'/'. $Current;
                    array_push($content, $current_adress);
                }
            }
        }
    }
    closedir($dir); 
    return $content;
}

# Paul's Simple Diff Algorithm v 0.1 : http://paulbutler.org/archives/a-simple-diff-algorithm-in-php/
function diff($old, $new)
{
    $matrix = array();
    $maxlen = 0;
    foreach ($old as $oindex => $ovalue) {
        $nkeys = array_keys($new, $ovalue);
        foreach ($nkeys as $nindex) {
            $matrix[$oindex][$nindex] = isset($matrix[$oindex - 1][$nindex - 1]) ?
                $matrix[$oindex - 1][$nindex - 1] + 1 : 1;
            if ($matrix[$oindex][$nindex] > $maxlen) {
                $maxlen = $matrix[$oindex][$nindex];
                $omax = $oindex + 1 - $maxlen;
                $nmax = $nindex + 1 - $maxlen;
            }
        }
    }
    if ($maxlen == 0)
        return array(array('d'=>$old, 'i'=>$new));
    return array_merge(
        diff(array_slice($old, 0, $omax), array_slice($new, 0, $nmax)),
        array_slice($new, $nmax, $maxlen),
        diff(array_slice($old, $omax + $maxlen), array_slice($new, $nmax + $maxlen)));
}

/*===================*/
/* Variables         */
/*===================*/
require("config-default.php");
include("config.php");
$folder = "photos";

$content = array();
$content = listFiles($content, $folder, $SkipExts, $SkipObjects);
usort($content, function ($a, $b) { return filemtime($a) < filemtime($b); });

if (is_writeable(".")) {
    $to_store = "";
    $old_files_list  = "db_old_files"; //list of files in ./photos
    $db_feed_source = "db_feed_source";
    $db_rss_timestamp = "db_rss_timestamp";

    // Init files
    if (!file_exists($old_files_list)) {
        file_put_contents($old_files_list, "");
    }
    if (!file_exists($db_feed_source)) {
        file_put_contents($db_feed_source, "");
    }
    if (!file_exists($db_rss_timestamp)) {
        file_put_contents($db_rss_timestamp, "");
    }

    /*===================*/
    /* Computing         */
    /*===================*/
    #Todo : ajouter une condition : dois-je regénérer le flux ou utiliser les anciens fichiers ?
    $temp = file_get_contents($db_feed_source);
    $last_rss_gen = file_get_contents($db_rss_timestamp);
    $current_time = time();
    // If the RSS generation is already launched, don't do a second generation at the same time
    if (($current_time - $last_rss_gen) > $rss_refresh_interval && file_exists("rss.locker") == false) {
        file_put_contents("rss.locker", "");
        file_put_contents($db_rss_timestamp, time());
        // Load the list from files.
        $old_files_list_content = explode("\n", file_get_contents($old_files_list));
        $new_files_list_content = $content; #debug
        // Generate and stock new elements
        $differences = diff($old_files_list_content, $new_files_list_content);
        for ($i=0; $i < count($differences); $i++) {
            if (is_array($differences[$i])) {
                for ($j=0; $j < count($differences[$i]["i"]); $j++) {
                    if (strlen($differences[$i]["i"][$j]) > 2) {
                        $to_store .= $differences[$i]["i"][$j] . "\n";
                    }
                }
            }
        }
        // Add new elements at the top of the feed's source
        $temp = $to_store . $temp;
        file_put_contents($db_feed_source, $temp);
        // Store the current file list for the next generation
        file_put_contents($old_files_list, join("/n", $content));
        unlink("rss.locker");
    }
    $content = explode("\n", $temp);
}

/*===================*/
/* XML Gen           */
/*===================*/
header('Content-Type: text/xml');
echo "<?xml version='1.0' encoding='UTF-8'?>\n";
echo "<rss version='2.0'>\n<channel>";
echo "<title>$title</title>";
echo "<link>$gallery_link</link>";
echo "<description>$description</description>\n";
for ($i=0; $i < $nb_items_rss && $i < count($content); $i++) {
    if (empty($content[$i]))
        continue;
    $link = $gallery_link . '/' . str_replace(' ', '%20', $content[$i]);
    echo "<item>\n";
    echo " <title>" . basename($link) . "</title>\n";
    echo " <link>". $link . "</link>\n";
    echo " <guid>". $link . "</guid>\n";
    echo " <description><![CDATA[ <img src='" . $link . "'> ]]></description>\n";
    echo " <pubDate>" . date ("D, j M Y H:i:s O", filemtime($content[$i])) . "</pubDate>";
    echo "</item>\n";
}
echo "</channel></rss>\n";