bin: read system-theme wallpapers from a config file; find photocollage through symlinks

system-theme sources ~/.config/system-theme/config, so wallpapers can be
set without the session environment. imgcollage resolves its own path, so a
symlink to it on PATH still finds the vendored photocollage beside the real
file.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

2 files changed, 8 insertions, 4 deletions

diff --git a/bin/imgcollage b/bin/imgcollage
index 6211f87..50ef803 100755
--- a/bin/imgcollage
+++ b/bin/imgcollage
@@ -14,7 +14,7 @@ import os
 import random
 import sys
 
-sys.path.insert(0, os.path.dirname(os.path.abspath(__file__)))
+sys.path.insert(0, os.path.dirname(os.path.realpath(__file__)))
 
 from photocollage import collage, render  # noqa: E402
 
diff --git a/bin/system-theme b/bin/system-theme
index 862b243..69c7a1f 100755
--- a/bin/system-theme
+++ b/bin/system-theme
@@ -1,10 +1,14 @@
 #!/usr/bin/env sh
 # Switch the COSMIC desktop between light and dark mode, and optionally the
 # wallpaper with it: set SYSTEM_THEME_WALLPAPER_DARK and
-# SYSTEM_THEME_WALLPAPER_LIGHT to image files. Emacs's auto-dark follows the
-# desktop's mode on its own. On another desktop, this is the file to rewrite.
+# SYSTEM_THEME_WALLPAPER_LIGHT to image files, in the environment or in
+# ~/.config/system-theme/config. Emacs's auto-dark follows the desktop's mode
+# on its own. On another desktop, this is the file to rewrite.
 
-COSMIC="${XDG_CONFIG_HOME:-$HOME/.config}/cosmic"
+CONFIG="${XDG_CONFIG_HOME:-$HOME/.config}"
+COSMIC="$CONFIG/cosmic"
+# shellcheck source=/dev/null
+[ -f "$CONFIG/system-theme/config" ] && . "$CONFIG/system-theme/config"
 
 set_wallpaper() {
     [ -n "$1" ] || return 0