Full rewrite

.github/scripts/check-filename-format.sh

@@ -0,0 +1,62 @@
+#!/usr/bin/env bash
+# Validate wallpaper filenames against the naming convention described in README.md:
+#   wallpaper-name_tag1_tag2.png
+# - name: lowercase letters/digits, words separated by "-"
+# - tags: lowercase letters, words separated by "-", tags separated by "_"
+# - only .png and .gif are accepted
+# - gifs must carry the "animated" tag
+# - every gif must have a same-named .png counterpart
+
+set -uo pipefail
+
+wallpapers_dir="wallpapers"
+name_re='^[a-z0-9]+(-[a-z0-9]+)*(_[a-z]+(-[a-z]+)*)*$'
+status=0
+
+if [[ ! -d "$wallpapers_dir" ]]; then
+  echo "No $wallpapers_dir directory found, skipping."
+  exit 0
+fi
+
+shopt -s nullglob
+for file in "$wallpapers_dir"/*; do
+  [[ -f "$file" ]] || continue
+  filename=$(basename "$file")
+  basename="${filename%.*}"
+  ext="${filename##*.}"
+
+  if [[ "$ext" != "png" && "$ext" != "gif" ]]; then
+    echo "❌ $filename: only .png and .gif files are accepted"
+    status=1
+    continue
+  fi
+
+  if [[ ! "$basename" =~ $name_re ]]; then
+    echo "❌ $filename: invalid name/tags, expected wallpaper-name_tag1_tag2 (lowercase, '-' separated words, '_' separated tags)"
+    status=1
+    continue
+  fi
+
+  if [[ "$ext" == "gif" ]]; then
+    IFS='_' read -r -a parts <<<"$basename"
+    has_animated=0
+    for tag in "${parts[@]:1}"; do
+      [[ "$tag" == "animated" ]] && has_animated=1
+    done
+    if [[ "$has_animated" -eq 0 ]]; then
+      echo "❌ $filename: gif files must include the 'animated' tag"
+      status=1
+    fi
+
+    if [[ ! -f "$wallpapers_dir/$basename.png" ]]; then
+      echo "❌ $filename: missing matching static $basename.png"
+      status=1
+    fi
+  fi
+done
+
+if [[ "$status" -eq 0 ]]; then
+  echo "✅ All wallpaper filenames are valid."
+fi
+
+exit "$status"