From dd7006c850e1f973c214f70eee87a054b00f19e7 Mon Sep 17 00:00:00 2001
From: nicm <nicm>
Date: Fri, 26 Feb 2021 07:53:26 +0000
Subject: [PATCH] Add a couple of format variables for active and last window
 index.

---
 format.c | 28 ++++++++++++++++++++++++++++
 tmux.1   |  6 ++++--
 2 files changed, 32 insertions(+), 2 deletions(-)

diff --git a/format.c b/format.c
index a9694bab..00413bae 100644
--- a/format.c
+++ b/format.c
@@ -2099,6 +2099,28 @@ format_cb_version(__unused struct format_tree *ft)
 	return (xstrdup(getversion()));
 }
 
+/* Callback for active_window_index. */
+static void *
+format_cb_active_window_index(struct format_tree *ft)
+{
+	if (ft->s != NULL)
+		return (format_printf("%u", ft->s->curw->idx));
+	return (NULL);
+}
+
+/* Callback for last_window_index. */
+static void *
+format_cb_last_window_index(struct format_tree *ft)
+{
+	struct winlink	*wl;
+
+	if (ft->s != NULL) {
+		wl = RB_MAX(winlinks, &ft->s->windows);
+		return (format_printf("%u", wl->idx));
+	}
+	return (NULL);
+}
+
 /* Callback for window_active. */
 static void *
 format_cb_window_active(struct format_tree *ft)
@@ -2496,6 +2518,9 @@ struct format_table_entry {
  * Only variables which are added by the caller go into the tree.
  */
 static const struct format_table_entry format_table[] = {
+	{ "active_window_index", FORMAT_TABLE_STRING,
+	  format_cb_active_window_index
+	},
 	{ "alternate_on", FORMAT_TABLE_STRING,
 	  format_cb_alternate_on
 	},
@@ -2631,6 +2656,9 @@ static const struct format_table_entry format_table[] = {
 	{ "keypad_flag", FORMAT_TABLE_STRING,
 	  format_cb_keypad_flag
 	},
+	{ "last_window_index", FORMAT_TABLE_STRING,
+	  format_cb_last_window_index
+	},
 	{ "mouse_all_flag", FORMAT_TABLE_STRING,
 	  format_cb_mouse_all_flag
 	},
diff --git a/tmux.1 b/tmux.1
index c3164e8f..a88a1d34 100644
--- a/tmux.1
+++ b/tmux.1
@@ -4756,6 +4756,7 @@ will be replaced by
 The following variables are available, where appropriate:
 .Bl -column "XXXXXXXXXXXXXXXXXXX" "XXXXX"
 .It Sy "Variable name" Ta Sy "Alias" Ta Sy "Replaced with"
+.It Li "active_window_index" Ta "" Ta "Index of active window in session"
 .It Li "alternate_on" Ta "" Ta "1 if pane is in alternate screen"
 .It Li "alternate_saved_x" Ta "" Ta "Saved cursor X in alternate screen"
 .It Li "alternate_saved_y" Ta "" Ta "Saved cursor Y in alternate screen"
@@ -4763,7 +4764,6 @@ The following variables are available, where appropriate:
 .It Li "buffer_name" Ta "" Ta "Name of buffer"
 .It Li "buffer_sample" Ta "" Ta "Sample of start of buffer"
 .It Li "buffer_size" Ta "" Ta "Size of the specified buffer in bytes"
-.It Li "config_files" Ta "" Ta "List of configuration files loaded"
 .It Li "client_activity" Ta "" Ta "Time client last had activity"
 .It Li "client_cell_height" Ta "" Ta "Height of each client cell in pixels"
 .It Li "client_cell_width" Ta "" Ta "Width of each client cell in pixels"
@@ -4790,6 +4790,7 @@ The following variables are available, where appropriate:
 .It Li "command_list_alias" Ta "" Ta "Command alias if listing commands"
 .It Li "command_list_name" Ta "" Ta "Command name if listing commands"
 .It Li "command_list_usage" Ta "" Ta "Command usage if listing commands"
+.It Li "config_files" Ta "" Ta "List of configuration files loaded"
 .It Li "copy_cursor_line" Ta "" Ta "Line the cursor is on in copy mode"
 .It Li "copy_cursor_word" Ta "" Ta "Word under cursor in copy mode"
 .It Li "copy_cursor_x" Ta "" Ta "Cursor X position in copy mode"
@@ -4812,6 +4813,7 @@ The following variables are available, where appropriate:
 .It Li "insert_flag" Ta "" Ta "Pane insert flag"
 .It Li "keypad_cursor_flag" Ta "" Ta "Pane keypad cursor flag"
 .It Li "keypad_flag" Ta "" Ta "Pane keypad flag"
+.It Li "last_window_index" Ta "" Ta "Index of last window in session"
 .It Li "line" Ta "" Ta "Line number in the list"
 .It Li "mouse_all_flag" Ta "" Ta "Pane mouse all flag"
 .It Li "mouse_any_flag" Ta "" Ta "Pane mouse any flag"
@@ -4867,8 +4869,8 @@ The following variables are available, where appropriate:
 .It Li "scroll_position" Ta "" Ta "Scroll position in copy mode"
 .It Li "scroll_region_lower" Ta "" Ta "Bottom of scroll region in pane"
 .It Li "scroll_region_upper" Ta "" Ta "Top of scroll region in pane"
-.It Li "search_present" Ta "" Ta "1 if search started in copy mode"
 .It Li "search_match" Ta "" Ta "Search match if any"
+.It Li "search_present" Ta "" Ta "1 if search started in copy mode"
 .It Li "selection_active" Ta "" Ta "1 if selection started and changes with the cursor in copy mode"
 .It Li "selection_end_x" Ta "" Ta "X position of the end of the selection"
 .It Li "selection_end_y" Ta "" Ta "Y position of the end of the selection"