cleanup: use DateTime to format dates

Closes #270

Modifications:
- replace custom date parsing by DateTime calls
- use proper date formatting for RSS feeds

Deletions:
- linkdate2timestamp()
- linkdate2rfc822
- linkdate2iso8601

Signed-off-by: VirtualTam <virtualtam@flibidi.net>

3 files changed, 29 insertions, 43 deletions

diff --git a/application/LinkDB.php b/application/LinkDB.php
index 9f4d3e3c..9488ac45 100644
--- a/application/LinkDB.php
+++ b/application/LinkDB.php
@@ -32,6 +32,9 @@ class LinkDB implements Iterator, Countable, ArrayAccess
     // Links are stored as a PHP serialized string
     private $_datastore;
 
+    // Link date storage format
+    const LINK_DATE_FORMAT = 'Ymd_His';
+
     // Datastore PHP prefix
     protected static $phpPrefix = '<?php /* ';
 
diff --git a/index.php b/index.php
index 3a63319c..12b6e04d 100644
--- a/index.php
+++ b/index.php
@@ -551,33 +551,6 @@ function getMaxFileSize()
     return $maxsize;
 }
 
-/*  Converts a linkdate time (YYYYMMDD_HHMMSS) of an article to a timestamp (Unix epoch)
-    (used to build the ADD_DATE attribute in Netscape-bookmarks file)
-    PS: I could have used strptime(), but it does not exist on Windows. I'm too kind. */
-function linkdate2timestamp($linkdate)
-{
-    if(strcmp($linkdate, '_000000') !== 0 || !$linkdate){
-        $Y=$M=$D=$h=$m=$s=0;
-        $r = sscanf($linkdate,'%4d%2d%2d_%2d%2d%2d',$Y,$M,$D,$h,$m,$s);
-        return mktime($h,$m,$s,$M,$D,$Y);
-    }
-    return time();
-}
-
-/*  Converts a linkdate time (YYYYMMDD_HHMMSS) of an article to a RFC822 date.
-    (used to build the pubDate attribute in RSS feed.)  */
-function linkdate2rfc822($linkdate)
-{
-    return date('r',linkdate2timestamp($linkdate)); // 'r' is for RFC822 date format.
-}
-
-/*  Converts a linkdate time (YYYYMMDD_HHMMSS) of an article to a ISO 8601 date.
-    (used to build the updated tags in ATOM feed.)  */
-function linkdate2iso8601($linkdate)
-{
-    return date('c',linkdate2timestamp($linkdate)); // 'c' is for ISO 8601 date format.
-}
-
 // ------------------------------------------------------------------------------------------
 // Token management for XSRF protection
 // Token should be used in any form which acts on data (create,update,delete,import...).
@@ -769,14 +742,16 @@ function showRSS()
     {
         $link = $linksToDisplay[$keys[$i]];
         $guid = $pageaddr.'?'.smallHash($link['linkdate']);
-        $rfc822date = linkdate2rfc822($link['linkdate']);
+        $date = DateTime::createFromFormat(LinkDB::LINK_DATE_FORMAT, $link['linkdate']);
         $absurl = $link['url'];
         if (startsWith($absurl,'?')) $absurl=$pageaddr.$absurl;  // make permalink URL absolute
         if ($usepermalinks===true)
             echo '<item><title>'.$link['title'].'</title><guid isPermaLink="true">'.$guid.'</guid><link>'.$guid.'</link>';
         else
             echo '<item><title>'.$link['title'].'</title><guid isPermaLink="false">'.$guid.'</guid><link>'.$absurl.'</link>';
-        if (!$GLOBALS['config']['HIDE_TIMESTAMPS'] || isLoggedIn()) echo '<pubDate>'.escape($rfc822date)."</pubDate>\n";
+        if (!$GLOBALS['config']['HIDE_TIMESTAMPS'] || isLoggedIn()) {
+            echo '<pubDate>'.escape($date->format(DateTime::RSS))."</pubDate>\n";
+        }
         if ($link['tags']!='') // Adding tags to each RSS entry (as mentioned in RSS specification)
         {
             foreach(explode(' ',$link['tags']) as $tag) { echo '<category domain="'.$pageaddr.'">'.$tag.'</category>'."\n"; }
@@ -857,8 +832,9 @@ function showATOM()
     {
         $link = $linksToDisplay[$keys[$i]];
         $guid = $pageaddr.'?'.smallHash($link['linkdate']);
-        $iso8601date = linkdate2iso8601($link['linkdate']);
-        $latestDate = max($latestDate,$iso8601date);
+        $date = DateTime::createFromFormat(LinkDB::LINK_DATE_FORMAT, $link['linkdate']);
+        $iso8601date = $date->format(DateTime::ISO8601);
+        $latestDate = max($latestDate, $iso8601date);
         $absurl = $link['url'];
         if (startsWith($absurl,'?')) $absurl=$pageaddr.$absurl;  // make permalink URL absolute
         $entries.='<entry><title>'.$link['title'].'</title>';
@@ -866,7 +842,10 @@ function showATOM()
             $entries.='<link href="'.$guid.'" /><id>'.$guid.'</id>';
         else
             $entries.='<link href="'.$absurl.'" /><id>'.$guid.'</id>';
-        if (!$GLOBALS['config']['HIDE_TIMESTAMPS'] || isLoggedIn()) $entries.='<updated>'.escape($iso8601date).'</updated>';
+
+        if (!$GLOBALS['config']['HIDE_TIMESTAMPS'] || isLoggedIn()) {
+            $entries.='<updated>'.escape($iso8601date).'</updated>';
+        }
 
         // Add permalink in description
         $descriptionlink = '(<a href="'.$guid.'">Permalink</a>)';
@@ -972,8 +951,7 @@ function showDailyRSS() {
 
     // For each day.
     foreach ($days as $day => $linkdates) {
-        $daydate = linkdate2timestamp($day.'_000000'); // Full text date
-        $rfc822date = linkdate2rfc822($day.'_000000');
+        $dayDate = DateTime::createFromFormat(LinkDB::LINK_DATE_FORMAT, $day.'_000000');
         $absurl = escape(index_url($_SERVER).'?do=daily&day='.$day);  // Absolute URL of the corresponding "Daily" page.
 
         // Build the HTML body of this RSS entry.
@@ -986,7 +964,8 @@ function showDailyRSS() {
             $l = $LINKSDB[$linkdate];
             $l['formatedDescription'] = format_description($l['description'], $GLOBALS['redirector']);
             $l['thumbnail'] = thumbnail($l['url']);
-            $l['timestamp'] = linkdate2timestamp($l['linkdate']);
+            $l_date = DateTime::createFromFormat(LinkDB::LINK_DATE_FORMAT, $l['linkdate']);
+            $l['timestamp'] = $l_date->getTimestamp();
             if (startsWith($l['url'], '?')) {
                 $l['url'] = index_url($_SERVER) . $l['url'];  // make permalink URL absolute
             }
@@ -996,10 +975,10 @@ function showDailyRSS() {
         // Then build the HTML for this day:
         $tpl = new RainTPL;
         $tpl->assign('title', $GLOBALS['title']);
-        $tpl->assign('daydate', $daydate);
+        $tpl->assign('daydate', $dayDate->getTimestamp());
         $tpl->assign('absurl', $absurl);
         $tpl->assign('links', $links);
-        $tpl->assign('rfc822date', escape($rfc822date));
+        $tpl->assign('rssdate', escape($dayDate->format(DateTime::RSS)));
         $html = $tpl->draw('dailyrss', $return_string=true);
 
         echo $html . PHP_EOL;
@@ -1055,7 +1034,8 @@ function showDaily($pageBuilder)
         $linksToDisplay[$key]['taglist']=$taglist;
         $linksToDisplay[$key]['formatedDescription'] = format_description($link['description'], $GLOBALS['redirector']);
         $linksToDisplay[$key]['thumbnail'] = thumbnail($link['url']);
-        $linksToDisplay[$key]['timestamp'] = linkdate2timestamp($link['linkdate']);
+        $date = DateTime::createFromFormat(LinkDB::LINK_DATE_FORMAT, $link['linkdate']);
+        $linksToDisplay[$key]['timestamp'] = $date->getTimestamp();
     }
 
     /* We need to spread the articles on 3 columns.
@@ -1080,11 +1060,12 @@ function showDaily($pageBuilder)
         $fill[$index]+=$length;
     }
 
+    $dayDate = DateTime::createFromFormat(LinkDB::LINK_DATE_FORMAT, $day.'_000000');
     $data = array(
         'linksToDisplay' => $linksToDisplay,
         'linkcount' => count($LINKSDB),
         'cols' => $columns,
-        'day' => linkdate2timestamp($day.'_000000'),
+        'day' => $dayDate->getTimestamp(),
         'previousday' => $previousday,
         'nextday' => $nextday,
     );
@@ -1799,7 +1780,8 @@ HTML;
                ($exportWhat=='private' && $link['private']!=0) ||
                ($exportWhat=='public' && $link['private']==0))
             {
-                echo '<DT><A HREF="'.$link['url'].'" ADD_DATE="'.linkdate2timestamp($link['linkdate']).'" PRIVATE="'.$link['private'].'"';
+                $date = DateTime::createFromFormat(LinkDB::LINK_DATE_FORMAT, $link['linkdate']);
+                echo '<DT><A HREF="'.$link['url'].'" ADD_DATE="'.$date->getTimestamp().'" PRIVATE="'.$link['private'].'"';
                 if ($link['tags']!='') echo ' TAGS="'.str_replace(' ',',',$link['tags']).'"';
                 echo '>'.$link['title']."</A>\n";
                 if ($link['description']!='') echo '<DD>'.$link['description']."\n";
@@ -2042,7 +2024,8 @@ function buildLinkList($PAGE,$LINKSDB)
         $link['description'] = format_description($link['description'], $GLOBALS['redirector']);
         $classLi =  ($i % 2) != 0 ? '' : 'publicLinkHightLight';
         $link['class'] = $link['private'] == 0 ? $classLi : 'private';
-        $link['timestamp'] = linkdate2timestamp($link['linkdate']);
+        $date = DateTime::createFromFormat(LinkDB::LINK_DATE_FORMAT, $link['linkdate']);
+        $link['timestamp'] = $date->getTimestamp();
         $taglist = explode(' ', $link['tags']);
         uasort($taglist, 'strcasecmp');
         $link['taglist'] = $taglist;
diff --git a/tpl/dailyrss.html b/tpl/dailyrss.html
index d959d6be..4133ca3e 100644
--- a/tpl/dailyrss.html
+++ b/tpl/dailyrss.html
@@ -2,7 +2,7 @@
     <title>{$title} - {function="strftime('%A %e %B %Y', $daydate)"}</title>
     <guid>{$absurl}</guid>
     <link>{$absurl}</link>
-    <pubDate>{$rfc822date}</pubDate>
+    <pubDate>{$rssdate}</pubDate>
     <description><![CDATA[
         {loop="links"}
                 <h3><a href="{$value.url}">{$value.title}</a></h3>
@@ -13,4 +13,4 @@
                 <br><br><hr>
         {/loop}
     ]]></description>
-</item>
\ No newline at end of file
+</item>