From a8f69739689ae0fe9a876bc211be42b5789d28e9 Mon Sep 17 00:00:00 2001
From: Julian Prein <druckdev@protonmail.com>
Date: Mon, 27 Jun 2022 12:05:21 +0200
Subject: [PATCH] tmux: Use pane-border as indicator for {copy,sync}

In tmux version 3.2 all style options were changed to string
options, making them support formats.[^1]

From that version on, use the pane-borders as indicator for the
{copy,sync}-mode instead of the prefix_highlight plugin.

Keep the pure style fallback, as Ubuntu 20.4 for example still only
ships with version 3.0a.

[^1]: https://github.com/tmux/tmux/commit/f03b61131b34079
---
 .config/tmux/tmux.conf | 25 +++++++++++++++++++------
 1 file changed, 19 insertions(+), 6 deletions(-)

diff --git a/.config/tmux/tmux.conf b/.config/tmux/tmux.conf
index 7fa20bd..c8b3447 100644
--- a/.config/tmux/tmux.conf
+++ b/.config/tmux/tmux.conf
@@ -134,17 +134,30 @@ set -g status-style bg=default,fg=white
 set -g message-command-style bg=default,fg=brightyellow
 set -g message-style bg=brightyellow,fg=black
 set -g mode-style bg=brightyellow,fg=black
-set -g pane-border-style bg=default,fg=brightblack
-set -g pane-active-border-style bg=default,fg=brightyellow
+
+# NOTE: `<` does string comparison with `strcmp()`. This means that the
+#       condition will break from a double digit major version (e.g. `10.0`) on.
+if -F "#{<:#{version},3.2}" {
+	# Use pure style default for tmux < 3.2 in combination with the
+	# prefix_highlight plugin.
+	set -g pane-border-style bg=default,fg=brightblack
+	set -g pane-active-border-style bg=default,fg=brightyellow
+
+	set -g @prefix_highlight_show_copy_mode 'on'
+	set -g @prefix_highlight_show_sync_mode 'on'
+	set -g @prefix_highlight_copy_mode_attr 'fg=black,bg=brightyellow'
+	set -g @prefix_highlight_sync_mode_attr 'fg=black,bg=brightred'
+} {
+	# From 3.2 on, we can use formats in styles, so that all indicators can be
+	# done by the borders.
+	set -g pane-border-style "#{?synchronize-panes,fg=brightred,fg=brightblack}"
+	set -g pane-active-border-style "#{?pane_in_mode,bg=brightyellow#,fg=brightblack,#{?synchronize-panes,fg=brightred,fg=brightyellow}}"
+}
 
 # Display in the status bar when the prefix was pressed, copy-mode is active, or
 # `synchronize-panes` is turned on
 set -g @prefix_highlight_fg 'brightyellow'
 set -g @prefix_highlight_bg 'default'
-set -g @prefix_highlight_show_copy_mode 'on'
-set -g @prefix_highlight_show_sync_mode 'on'
-set -g @prefix_highlight_copy_mode_attr 'fg=black,bg=brightyellow'
-set -g @prefix_highlight_sync_mode_attr 'fg=black,bg=brightred'
 set -g status-right "#{prefix_highlight}"
 set -g status-left "#{prefix_highlight}"