buffers/thread: more sophisticated heuristics for default weights

Should produce better results in most situations.

1 files changed, 14 insertions, 5 deletions

diff --git a/alot/buffers/thread.py b/alot/buffers/thread.py
index 1e751f1a..47b7f9d0 100644
--- a/alot/buffers/thread.py
+++ b/alot/buffers/thread.py
@@ -23,6 +23,9 @@ class ThreadBuffer(Buffer):
 
     modename = 'thread'
 
+    ui     = None
+    thread = None
+
     # list of the widgets containing the message body
     # indexed by its depth-first position in the thread tree
     _msg_widgets    = None
@@ -34,11 +37,12 @@ class ThreadBuffer(Buffer):
     # WidgetPlaceholder that wraps currently displayed message
     _cur_msg_holder = None
 
-    def __init__(self, thread):
+    def __init__(self, ui, thread):
         """
         :param thread: thread to display
         :type thread: :class:`~alot.db.Thread`
         """
+        self.ui            = ui
         self.thread        = thread
         self._indent_width = settings.get('thread_indent_replies')
 
@@ -121,10 +125,15 @@ class ThreadBuffer(Buffer):
             self._msg_widgets.append(msg_wgt)
             list_walker.append(wgt)
 
-        # the weight given to the thread-tree widget is proportional to the number of
-        # messages in it plus 1 (for surrounding decoration), up to the limit of
-        # 49 messages, when it is equal to the message body widget
-        tree_weight = min(0.01 * (len(self._msg_widgets) + 1), 0.5)
+        # approximate weight for one terminal line
+        # substract 3 for decoration and panels
+        line_weight = 1.0 / max(self.ui.get_cols_rows()[1] - 3, 1)
+
+        # the default weight given to the thread-tree widget is proportional to
+        # the number of messages in it plus 2 (for surrounding decoration) -
+        # scaled to approximately one line per message - up to maximum weight of
+        # half the screen
+        tree_weight = min(line_weight * (len(self._msg_widgets) + 2), 0.5)
         self.msgtree_weight = tree_weight
 
         if len(self._msg_widgets) > 0: