From fdc8785261d04be8df8158cf1eef192bf2d000e7 Mon Sep 17 00:00:00 2001
From: Siraaj Khandkar <siraaj@khandkar.net>
Date: Fri, 10 Jun 2022 13:07:00 -0400
Subject: [PATCH] Improve wallpaper-setting pipeline robustness

---
 home/.xlaunch.d/background |  8 ++++++--
 home/bin/wallpaper_fav     | 30 +++++++++++++++++++++++++++++-
 home/bin/wallpaper_review  |  2 +-
 3 files changed, 36 insertions(+), 4 deletions(-)

diff --git a/home/.xlaunch.d/background b/home/.xlaunch.d/background
index ab4c301..a02d34c 100755
--- a/home/.xlaunch.d/background
+++ b/home/.xlaunch.d/background
@@ -3,8 +3,12 @@
 set -e
 
 BG_COLOR='#b2b2a0'
-BG_IMAGE=$(< "$FILE_WALLPAPER_CURR")
 
 #xsetroot -solid "$BG_COLOR"
 hsetroot -solid "$BG_COLOR"   # Because xsetroot is incompatible with compton.
-feh --bg-scale "$BG_IMAGE"
+
+if test -f "$FILE_WALLPAPER_CURR"
+then
+    bg_image=$(< "$FILE_WALLPAPER_CURR")
+    feh --bg-scale "$bg_image"
+fi
diff --git a/home/bin/wallpaper_fav b/home/bin/wallpaper_fav
index 702cd9f..1a73af7 100755
--- a/home/bin/wallpaper_fav
+++ b/home/bin/wallpaper_fav
@@ -2,5 +2,33 @@
 
 set -e
 
-awk 'NR == 2 {sub("^" $1 " +" $2 " +" $3 " +", ""); print}' ~/.fehbg | xargs sha256sum >> "$FILE_WALLPAPER_FAVS"
+case "$1" in
+    '')
+        current_wallpaper_file=$(
+            awk '
+                NR == 2 {
+                    if (NF > 3) {
+                        # XXX Assume feh wrote a N>4-field command line, like:
+                        #         feh --no-fehbg --bg-scale $file
+                        sub("^" $1 " +" $2 " +" $3 " +", "")
+                    } else if (NF < 4) {
+                        # XXX Assume feh wrote a N<4-field command line, like:
+                        #         feh --bg-scale $file
+                        sub("^" $1 " +" $2 " +", "")
+                    } else {
+                        printf "[error] Unexpected number of fields in ~/.fehbg command: %s\n" $0 > "/dev/stderr"
+                        exit 1
+                    }
+                    print
+                    exit 0
+                }
+                ' \
+                ~/.fehbg \
+            | xargs  # Unquote the filename, which feh puts in single quotes.
+        );;
+    *)
+        current_wallpaper_file="$1"
+esac
+
+sha256sum "$current_wallpaper_file" >> "$FILE_WALLPAPER_FAVS"
 sort -u "$FILE_WALLPAPER_FAVS" | sponge "$FILE_WALLPAPER_FAVS"
diff --git a/home/bin/wallpaper_review b/home/bin/wallpaper_review
index b466255..5c6966a 100755
--- a/home/bin/wallpaper_review
+++ b/home/bin/wallpaper_review
@@ -109,7 +109,7 @@ paths_preview() {
                 (( i = (i + 1) % n ));;
             CMD_FAVORITE_ADD)
                 printf 'Adding to favorites set: "%s"\n' "$path" >&2
-                wallpaper_fav;;
+                wallpaper_fav "$path";;
             CMD_FAVORITE_REMOVE)
                 printf 'Removing from favorites set: "%s"\n' "$path" >&2
                 digest=$(sha256sum "$path" | awk '{print $1}')
-- 
2.20.1