update room scrollback limit to new api, update TODO

TODO.md

@@ -25,7 +25,6 @@ This helps with scalability
 ### Chat
 * echo "unknown/innappropriate command" in the console
 * break up lines on CR/LF, send multiple messages
-* Style timestamps and persona names
 * enforce # in room names or ignore it
 * auto-create/join channel on server start
 * jump from notification window to room with message

gui/griffon-app/controllers/com/muwire/gui/ChatRoomController.groovy

@@ -246,12 +246,8 @@ class ChatRoomController {
     private void trimLines() {
         if (model.settings.maxChatLines < 0)
             return
-        // TODO: update to JTextPane api
-//        while(view.roomTextArea.getLineCount() > model.settings.maxChatLines) {
-//            int line0Start = view.roomTextArea.getLineStartOffset(0)
-//            int line0End = view.roomTextArea.getLineEndOffset(0)
-//            view.roomTextArea.replaceRange(null, line0Start, line0End)
-//        }
+        while(view.getLineCount() > model.settings.maxChatLines) 
+            view.removeFirstLine()
     }
     
     void rejoinRoom() {

gui/griffon-app/views/com/muwire/gui/ChatRoomView.groovy

@@ -11,6 +11,7 @@ import javax.swing.JSplitPane
 import javax.swing.JTextPane
 import javax.swing.ListSelectionModel
 import javax.swing.SwingConstants
+import javax.swing.text.Element
 import javax.swing.text.Style
 import javax.swing.text.StyleConstants
 import javax.swing.text.StyleContext
@@ -208,4 +209,15 @@ class ChatRoomView {
         doc.insertString(doc.getEndPosition().getOffset() - 1, text, doc.getStyle("regular"))
         doc.insertString(doc.getEndPosition().getOffset() - 1, "\n", doc.getStyle("regular"))
     }
+    
+    int getLineCount() {
+        StyledDocument doc = roomTextArea.getStyledDocument()
+        doc.getDefaultRootElement().getElementCount() - 1
+    }
+    
+    void removeFirstLine() {
+        StyledDocument doc = roomTextArea.getStyledDocument()
+        Element element = doc.getParagraphElement(0)
+        doc.remove(0, element.getEndOffset())
+    }
 }