Fix some display bugs with read marker line, history, max prefix length, and chat refresh (bug #23153)

Some info about bugs fixed:
- when marker line (dotted) was on top of window (and not visible), this caused
  bug on last lines of buffer (not refreshed)
- marker line is not set for a buffer after a switch, only if buffer it not
  displayed in other window
- when we delete lines in a buffer (if lines > weechat.history.max_lines), we
  force a full refresh of chat if remaining lines is < to chat height
  and we compute again max prefix length for buffer (before max prefix length
  was always incremented, never decremented)

src/gui/curses/gui-curses-chat.c

@@ -142,7 +142,7 @@ gui_chat_get_real_width (struct t_gui_window *window)
 }
 
 /*
- * gui_chat_marker_for_line: return 1 if marker must be displayed before this
+ * gui_chat_marker_for_line: return 1 if marker must be displayed after this
  *                           line, or 0 if it must not
  */
 
@@ -158,7 +158,6 @@ gui_chat_marker_for_line (struct t_gui_buffer *buffer, struct t_gui_line *line)
         && (CONFIG_INTEGER(config_look_read_marker) != CONFIG_LOOK_READ_MARKER_DOTTED_LINE))
         return 0;
     
-    line = line->prev_line;
     while (line)
     {
         if (buffer->last_read_line == line)
@@ -167,7 +166,7 @@ gui_chat_marker_for_line (struct t_gui_buffer *buffer, struct t_gui_line *line)
         if (line->displayed)
             break;
         
-        line = line->prev_line;
+        line = line->next_line;
     }
     return 0;
 }
@@ -804,14 +803,6 @@ gui_chat_display_line (struct t_gui_window *window, struct t_gui_line *line,
     
     marker_line = gui_chat_marker_for_line (window->buffer, line);
     
-    if (marker_line)
-    {
-        gui_chat_display_horizontal_line (window, simulate);
-        gui_chat_display_new_line (window, num_lines, count,
-                                   &lines_displayed, simulate);
-        lines_displayed--;
-    }
-    
     /* display time and prefix */
     gui_chat_display_time_and_prefix (window, line, num_lines, count,
                                       &lines_displayed, simulate);
@@ -904,6 +895,13 @@ gui_chat_display_line (struct t_gui_window *window, struct t_gui_line *line,
         }
     }
     
+    if (marker_line && gui_chat_get_next_line_displayed (line))
+    {
+        gui_chat_display_horizontal_line (window, simulate);
+        gui_chat_display_new_line (window, num_lines, count,
+                                   &lines_displayed, simulate);
+    }
+    
     if (simulate)
     {
         window->win_chat_cursor_x = x;
@@ -940,9 +938,6 @@ gui_chat_display_line (struct t_gui_window *window, struct t_gui_line *line,
         }
     }
     
-    if (marker_line)
-        lines_displayed++;
-    
     return lines_displayed;
 }
 

src/gui/curses/gui-curses-window.c

@@ -633,7 +633,8 @@ gui_window_switch_to_buffer (struct t_gui_window *window,
     {
         window->start_line = NULL;
         window->start_line_pos = 0;
-        window->buffer->last_read_line = window->buffer->last_line;
+        if (window->buffer->num_displayed == 0)
+            window->buffer->last_read_line = window->buffer->last_line;
         if (buffer->last_read_line == buffer->last_line)
             buffer->last_read_line = NULL;
         gui_previous_buffer = window->buffer;

src/gui/gui-chat.c

@@ -652,8 +652,12 @@ gui_chat_line_has_highlight (struct t_gui_buffer *buffer,
 void
 gui_chat_line_free (struct t_gui_buffer *buffer, struct t_gui_line *line)
 {
+    int update_prefix_max_length;
+    struct t_gui_line *ptr_line;
     struct t_gui_window *ptr_win;
     
+    update_prefix_max_length = (line->prefix_length == buffer->prefix_max_length);
+    
     /* reset scroll for any window starting with this line */
     for (ptr_win = gui_windows; ptr_win; ptr_win = ptr_win->next_window)
     {
@@ -689,6 +693,17 @@ gui_chat_line_free (struct t_gui_buffer *buffer, struct t_gui_line *line)
     free (line);
     
     buffer->lines_count--;
+
+    if (update_prefix_max_length)
+    {
+        buffer->prefix_max_length = 0;
+        for (ptr_line = buffer->lines; ptr_line;
+             ptr_line = ptr_line->next_line)
+        {
+            if (ptr_line->prefix_length > buffer->prefix_max_length)
+                buffer->prefix_max_length = ptr_line->prefix_length;
+        }
+    }
 }
 
 /*
@@ -739,6 +754,7 @@ gui_chat_line_add (struct t_gui_buffer *buffer, time_t date,
                    const char *prefix, const char *message)
 {
     struct t_gui_line *new_line;
+    struct t_gui_window *ptr_win;
     
     new_line = malloc (sizeof (*new_line));
     if (!new_line)
@@ -811,6 +827,15 @@ gui_chat_line_add (struct t_gui_buffer *buffer, time_t date,
         && (buffer->lines_count > CONFIG_INTEGER(config_history_max_lines)))
     {
         gui_chat_line_free (buffer, buffer->lines);
+        for (ptr_win = gui_windows; ptr_win; ptr_win = ptr_win->next_window)
+        {
+            if ((ptr_win->buffer == buffer)
+                && (buffer->lines_count < ptr_win->win_chat_height))
+            {
+                gui_buffer_ask_chat_refresh (buffer, 2);
+                break;
+            }
+        }
     }
 }