[PATCH] gitk: make the 'Tags and Heads' window geometry sticky

[Michael Rappazzo <rappazzo@xxxxxxxxx>]

Currently, the Tags and Heads window always opens at a default position
and size, requiring users to reposition it each time. 

This change saves and restores the Tags and Heads window size and position
relative to the main gitk window. The geometry is stored in the config file
as `geometry(showrefs)` and persists between gitk sessions. The window
position is stored relative to the main window, so it maintains the same
spatial relationship when the main window is moved or when gitk is restarted
on different monitors.

Signed-off-by: Michael Rappazzo <rappazzo@xxxxxxxxx>
---
 gitk | 75 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++--
 1 file changed, 73 insertions(+), 2 deletions(-)

diff --git a/gitk b/gitk
index 6e4d71d585..49b2ceefc0 100755
--- a/gitk
+++ b/gitk
@@ -3114,6 +3114,19 @@ proc savestuff {w} {
         puts $f "set geometry(pwsash1) \"[.tf.histframe.pwclist sashpos 1] 1\""
         puts $f "set geometry(botwidth) [winfo width .bleft]"
         puts $f "set geometry(botheight) [winfo height .bleft]"
+        if {[winfo exists .showrefs]} {
+            set geom [parse_geometry [wm geometry .showrefs]]
+            set main_geom [parse_geometry [wm geometry .]]
+            if {[llength $geom] == 4 && [llength $main_geom] == 4} {
+                lassign $geom w h x y
+                lassign $main_geom mw mh mx my
+                set rel_x [expr {$x - $mx}]
+                set rel_y [expr {$y - $my}]
+                puts $f "set geometry(showrefs) \"${w}x${h}+${rel_x}+${rel_y}\""
+            }
+        } elseif {[info exists geometry(showrefs)]} {
+            puts $f "set geometry(showrefs) \"$geometry(showrefs)\""
+        }
 
         array set view_save {}
         array set views {}
@@ -10207,11 +10220,13 @@ proc showrefs {} {
     if {[winfo exists $top]} {
         raise $top
         refill_reflist
+        wm protocol $top WM_DELETE_WINDOW [list destroy_showrefs $top]
         return
     }
     ttk_toplevel $top
     wm title $top [mc "Tags and heads: %s" [file tail [pwd]]]
     make_transient $top .
+    wm protocol $top WM_DELETE_WINDOW [list destroy_showrefs $top]
     text $top.list -background $bgcolor -foreground $fgcolor \
         -selectbackground $selectbgcolor -font mainfont \
         -xscrollcommand "$top.xsb set" -yscrollcommand "$top.ysb set" \
@@ -10237,8 +10252,8 @@ proc showrefs {} {
     ttk::checkbutton $top.sort -text [mc "Sort refs by type"] \
         -variable sortrefsbytype -command {refill_reflist}
     grid $top.sort - -sticky w -pady 2
-    ttk::button $top.close -command [list destroy $top] -text [mc "Close"]
-    bind $top <Key-Escape> [list destroy $top]
+    ttk::button $top.close -command [list destroy_showrefs $top] -text [mc "Close"]
+    bind $top <Key-Escape> [list destroy_showrefs $top]
     grid $top.close -
     grid columnconfigure $top 0 -weight 1
     grid rowconfigure $top 0 -weight 1
@@ -10247,6 +10262,7 @@ proc showrefs {} {
     bind $top.list <ButtonRelease-1> {sel_reflist %W %x %y; break}
     set reflist {}
     refill_reflist
+    bind $top <Map> [list restore_showrefs_geometry $top]
 }
 
 proc sel_reflist {w x y} {
@@ -10279,6 +10295,61 @@ proc reflistfilter_change {n1 n2 op} {
     after 200 refill_reflist
 }
 
+proc parse_geometry {geom_string} {
+    if {[regexp {^(\d+)x(\d+)\+(-?\d+)\+(-?\d+)$} $geom_string -> w h x y]} {
+        return [list $w $h $x $y]
+    }
+    return {}
+}
+
+proc save_showrefs_geometry {top} {
+    global geometry
+
+    if {![winfo exists $top] || ![winfo exists .]} return
+
+    set geom [parse_geometry [wm geometry $top]]
+    set main_geom [parse_geometry [wm geometry .]]
+    if {[llength $geom] == 4 && [llength $main_geom] == 4} {
+        lassign $geom w h x y
+        lassign $main_geom mw mh mx my
+        set rel_x [expr {$x - $mx}]
+        set rel_y [expr {$y - $my}]
+        set geometry(showrefs) "${w}x${h}+${rel_x}+${rel_y}"
+    }
+}
+
+proc restore_showrefs_geometry {top} {
+    global geometry
+
+    if {![info exists geometry(showrefs)] || ![winfo exists $top] || ![winfo exists .]} return
+
+    set saved_geom [parse_geometry $geometry(showrefs)]
+    set main_geom [parse_geometry [wm geometry .]]
+    if {[llength $saved_geom] == 4 && [llength $main_geom] == 4} {
+        lassign $saved_geom w h rel_x rel_y
+        lassign $main_geom mw mh mx my
+
+        set abs_x [expr {$mx + $rel_x}]
+        set abs_y [expr {$my + $rel_y}]
+
+        # Ensure window stays on screen
+        set screen_w [winfo screenwidth .]
+        set screen_h [winfo screenheight .]
+        if {$abs_x < 0} { set abs_x 0 }
+        if {$abs_y < 0} { set abs_y 0 }
+        if {$abs_x + $w > $screen_w} { set abs_x [expr {$screen_w - $w}] }
+        if {$abs_y + $h > $screen_h} { set abs_y [expr {$screen_h - $h}] }
+
+        wm geometry $top "${w}x${h}+${abs_x}+${abs_y}"
+    }
+    bind $top <Map> {}
+}
+
+proc destroy_showrefs {top} {
+    save_showrefs_geometry $top
+    destroy $top
+}
+
 proc refill_reflist {} {
     global reflist reflistfilter showrefstop headids tagids otherrefids sortrefsbytype
     global curview upstreamofref
-- 
2.51.0