Make it possible to show less log entries again - fix owncloud/core#1593

* show "less" button only if there are more than 3 entries
 * only "remove" logs till last 3 entries

settings/js/log.js

@@ -26,9 +26,22 @@ OC.Log={
 				if(!result.remain){
 					$('#moreLog').css('display', 'none');
 				}
+				$('#lessLog').css('display', '');
 			}
 		});
 	},
+	showLess:function(count){
+		count = count || 10;
+		$('#moreLog').css('display', '');
+		$('html, body').animate({scrollTop: $(document).height()}, 800);
+		while(OC.Log.loaded > 3 && count){
+			$('#log tr').last().remove()
+			OC.Log.loaded -= 1;
+			count--;
+		}
+		if(OC.Log.loaded <= 3)
+			$('#lessLog').css('display', 'none');
+	},
 	addEntries:function(entries){
 		for(var i=0;i<entries.length;i++){
 			var entry=entries[i];
@@ -36,15 +49,15 @@ OC.Log={
 			var levelTd=$('<td/>');
 			levelTd.text(OC.Log.levels[entry.level]);
 			row.append(levelTd);
-			
+
 			var appTd=$('<td/>');
 			appTd.text(entry.app);
 			row.append(appTd);
-			
+
 			var messageTd=$('<td/>');
 			messageTd.text(entry.message);
 			row.append(messageTd);
-			
+
 			var timeTd=$('<td/>');
 			timeTd.text(formatDate(entry.time*1000));
 			row.append(timeTd);
@@ -58,4 +71,7 @@ $(document).ready(function(){
 	$('#moreLog').click(function(){
 		OC.Log.getMore();
 	})
+	$('#lessLog').click(function(){
+		OC.Log.showLess();
+	})
 });

settings/templates/admin.php

@@ -221,6 +221,7 @@ endfor;?>
 	</table>
 	<?php if ($_['entriesremain']): ?>
 	<input id='moreLog' type='button' value='<?php p($l->t('More'));?>...'>
+	<input id='lessLog' type='button' style='display:none' value='<?php p($l->t('Less'));?>...'>
 	<?php endif; ?>
 
 </fieldset>