Work in progress.

rtv/objects.py

@@ -316,7 +316,7 @@ class Navigator(object):
             page_index=0,
             cursor_index=0,
             inverted=False,
-            top_height=None):
+            top_item_height=None):
         """
         Params:
             valid_page_callback (func): This function, usually `Content.get`,
@@ -332,12 +332,16 @@ class Navigator(object):
                 inverted - The page is drawn from the bottom of the screen,
                     starting with the page index, up to the top of the
                     screen.
+            top_item_height (int): If this is set to a non-null value
+            The number of columns that the top-most item
+                should utilize if non-inverted. This is used for a special mode
+                where all items are drawn non-inverted except for the top one.
         """
 
         self.page_index = page_index
         self.cursor_index = cursor_index
         self.inverted = inverted
-        self.top_height = top_height
+        self.top_item_height = top_item_height
         self._page_cb = valid_page_cb
 
     @property
@@ -398,17 +402,21 @@ class Navigator(object):
                     # Flip the orientation and reset the cursor
                     self.flip(self.cursor_index)
                     self.cursor_index = 0
-                    self.top_height = None
+                    self.top_item_height = None
                     redraw = True
         else:
             if self.cursor_index > 0:
                 self.cursor_index -= 1
+                if self.top_item_height and self.cursor_index == 0:
+                    # Selecting the partially displayed item
+                    self.top_item_height = None
+                    redraw = True
             else:
                 self.page_index -= self.step
                 if self._is_valid(self.absolute_index):
                     # We have reached the beginning of the page - move the
                     # index
-                    self.top_height = None
+                    self.top_item_height = None
                     redraw = True
                 else:
                     self.page_index += self.step
@@ -482,6 +490,7 @@ class Navigator(object):
         self.page_index += (self.step * n_windows)
         self.cursor_index = n_windows - self.cursor_index
         self.inverted = not self.inverted
+        self.top_item_height = None
 
     def _is_valid(self, page_index):
         """

rtv/page.py

@@ -328,8 +328,7 @@ class Page(object):
         # 4.) Otherwise, this should ensure that the bottom element is always
         #     full visible and the cursor doesn't jump lines.
 
-        # Note: Should also disable drawing inverted if only one element
-        # Note: If only one comment, add (Not enough space to display)
+        # TODO: If only one comment, add (Not enough space to display)
 
         n_rows, n_cols = self.term.stdscr.getmaxyx()
         window = self.term.stdscr.derwin(
@@ -347,20 +346,24 @@ class Page(object):
         cancel_inverted = True
         current_row = (win_n_rows - 1) if inverted else 0
         available_rows = (win_n_rows - 1) if inverted else win_n_rows
-        top_height = self.nav.top_height if not inverted else None
+        top_item_height = None if inverted else self.nav.top_item_height
         for data in self.content.iterate(page_index, step, win_n_cols - 2):
             subwin_n_rows = min(available_rows, data['n_rows'])
-            if top_height:
-                subwin_n_rows = min(subwin_n_rows, top_height)
+            subwin_inverted = inverted
+            if top_item_height is not None:
+                # Special case when top_item_height is given. This will only
+                # be applied to the first item that is drawn.
+                subwin_n_rows = min(subwin_n_rows, top_item_height)
+                subwin_inverted = True
+                top_item_height = None
             subwin_n_cols = win_n_cols - data['offset']
             start = current_row - subwin_n_rows if inverted else current_row
             subwindow = window.derwin(
                 subwin_n_rows, subwin_n_cols, start, data['offset'])
-            attr = self._draw_item(subwindow, data, top_height or inverted)
-            self._subwindows.append((subwindow, attr, subwin_n_rows))
+            attr = self._draw_item(subwindow, data, subwin_inverted)
+            self._subwindows.append((subwindow, attr))
             available_rows -= (subwin_n_rows + 1)  # Add one for the blank line
             current_row += step * (subwin_n_rows + 1)
-            top_height = None
             if available_rows <= 0:
                 # Indicate the page is full and we can keep the inverted screen.
                 cancel_inverted = False

rtv/submission.py

@@ -34,8 +34,14 @@ class SubmissionPage(Page):
         current_index = self.nav.absolute_index
         self.content.toggle(current_index)
         if self.nav.inverted:
-            self.nav.top_height = self._subwindows[-1][2]
+            # Special case when inverted and toggling a comment. We want to
+            # ensure that when we re-draw the page, the cursor stays at its
+            # current absolute position. Do this by turning off inversion and
+            # applying an offset to the top item.
+            window = self._subwindows[-1]
+            n_rows, _ = window.getmaxyx()
             self.nav.flip(len(self._subwindows) - 1)
+            self.nav.top_item_height = n_rows
 
     @SubmissionController.register(Command('SUBMISSION_EXIT'))
     def exit_submission(self):