awww -> awww + swaybg

顺便修修readme：减少md代码块以应对ly gitea黑色主题的蜜汁渲染

bin/chbg

@@ -3,7 +3,11 @@ set -euo pipefail
 
 THIS_COMMAND=$(basename "$0")
 IMG_MAGICK="magick"
-WP_DIR="${XDG_DATA_HOME:-$HOME/.local/share}"
+SERVICE_NAME="swaybg.service"
+
+WP_DIR="${XDG_CACHE_HOME:-$HOME/.cache}"
+WP_FILE="$WP_DIR/wallpaper"
+BLUR_WP="$WP_DIR/wallpaper_blur"
 
 usage() {
   cat << EOF
@@ -12,7 +16,7 @@ Options:
   -d, --dir OUTPUT_PATH   Directory to store chosen image. (default: $WP_DIR)
   -h, --help              Show this help message and exit.
 Notes:
-  - Images can be provided as arguments or via stdin. If both are used, they are combined.
+  - This script needs 'swaybg.service' to be set up for overview background support (unless awww #521 solved). See niri documentation for details.
   - Web URLs are also supported (via 'curl' or 'wget' downloading).
   - If multiple images are provided, one will be randomly picked each time the script is executed.
 EOF
@@ -36,8 +40,8 @@ while [[ $# -gt 0 ]]; do
   esac
 done
 
-if ! command -v swww >/dev/null 2>&1; then
-  echo "!) 'swww' command not found. Unable to comply." >&2
+if ! command -v awww >/dev/null 2>&1; then
+  echo "x) 'awww' not found. Unable to comply." >&2
   exit 2
 fi
 
@@ -46,7 +50,7 @@ if command -v magick >/dev/null 2>&1; then
 elif command -v convert >/dev/null 2>&1; then
   IMG_MAGICK="convert"
 else
-  echo "!) 'magick' or 'convert' command not found. Image processing unavailable." >&2
+  echo "x) 'magick' or 'convert' not found. Image processing unavailable." >&2
   exit 2
 fi
 
@@ -61,7 +65,7 @@ set_wallpaper() {
   (( fw > 3840 && fh > 2160 )) && {
     finput=$(mktemp "${TMPDIR:-/tmp}/chbg.XXXXXXXX.webp")
     trap 'rm -f "$finput"' EXIT
-    echo "-> image too large, resizing ..."
+    echo " -> image too large, resizing ..."
     # echo "DEBUG: resized image at $finput"
     $IMG_MAGICK "$1" -resize "3840x2160^" \
       -quality 90 \
@@ -69,14 +73,22 @@ set_wallpaper() {
       -define webp:alpha-quality=100 "$finput"
   }
 
-  echo -n "-> making blurred version of '${1##*/}' ... "
-  cp $finput $WP_DIR/.wallpaper
-  $IMG_MAGICK $WP_DIR/.wallpaper -filter Gaussian -blur 0x30 $WP_DIR/.wallpaper_blur
+  echo -n " -> making blurred version of '${1##*/}' ... "
+  cp "$finput" "$WP_FILE"
+  $IMG_MAGICK "$WP_FILE" -filter Gaussian -blur 0x30 "$BLUR_WP"
   echo "Done."
 
-  # 原工具现在更名为 awww，但留下了 bug：https://codeberg.org/LGFae/awww/issues/521
-  swww img $WP_DIR/.wallpaper
-  swww img $WP_DIR/.wallpaper_blur --namespace blur
+  awww img "$WP_FILE" --transition-type=random
+
+  if [[ -f "$HOME/.config/systemd/user/niri.service.wants/$SERVICE_NAME" ]]; then
+    echo " -> restarting $SERVICE_NAME ..."
+    systemctl --user restart "$SERVICE_NAME"
+  else
+    echo " !) '$SERVICE_NAME' didn't loaded by niri. Won't reload backdrop." >&2
+    echo "  => See niri documentation for setting up swaybg systemd unit." >&2
+    echo "  => Or wait for awww #521 on codeberg being resolved." >&2
+    exit 1
+  fi
 }
 
 imagepool=()
@@ -132,7 +144,7 @@ if command -v curl >/dev/null 2>&1; then
 elif command -v wget >/dev/null 2>&1; then
   wget -qO "$tmpfile" "$randomimage"
 else
-  echo "!) Unable to fetch image without 'curl' or 'wget'." >&2
+  echo "x) Unable to fetch image without 'curl' or 'wget'." >&2
   exit 2
 fi
 set_wallpaper "$tmpfile"