setup-opds.sh: replace hardcoded books path with dynamic spoke mount listing

hub/setup-opds.sh

@@ -93,8 +93,42 @@ read -rp "Hub user [armbian]: " HUB_USER
 HUB_USER="${HUB_USER:-armbian}"
 HUB_HOME="/home/$HUB_USER"
 
-read -rp "Path to books directory [${HUB_HOME}/mnt/grace/st/data/books/justin]: " BOOKS_PATH
+MOUNT_BASE="${HUB_HOME}/mnt"
-BOOKS_PATH="${BOOKS_PATH:-${HUB_HOME}/mnt/grace/st/data/books/justin}"
+AVAILABLE_MOUNTS=()
+if [ -d "$MOUNT_BASE" ]; then
+    while IFS= read -r mountdir; do
+        AVAILABLE_MOUNTS+=("$mountdir")
+    done < <(find "$MOUNT_BASE" -mindepth 1 -maxdepth 1 -type d | sort)
+fi
+
+if [ ${#AVAILABLE_MOUNTS[@]} -gt 0 ]; then
+    echo "Available spoke mounts:"
+    for i in "${!AVAILABLE_MOUNTS[@]}"; do
+        echo "  $i) ${AVAILABLE_MOUNTS[$i]}"
+    done
+    echo "  m) Enter path manually"
+    echo ""
+    read -rp "Choose a mount [0]: " MOUNT_CHOICE
+    MOUNT_CHOICE="${MOUNT_CHOICE:-0}"
+    if [[ "$MOUNT_CHOICE" == "m" ]]; then
+        read -rp "Path to books directory: " BOOKS_PATH
+    elif [[ "$MOUNT_CHOICE" =~ ^[0-9]+$ ]] && [ "$MOUNT_CHOICE" -lt "${#AVAILABLE_MOUNTS[@]}" ]; then
+        BASE="${AVAILABLE_MOUNTS[$MOUNT_CHOICE]}"
+        read -rp "Subdirectory within ${BASE} (leave blank for root): " SUBDIR
+        if [ -n "$SUBDIR" ]; then
+            BOOKS_PATH="${BASE}/${SUBDIR}"
+        else
+            BOOKS_PATH="$BASE"
+        fi
+    else
+        die "Invalid choice."
+    fi
+else
+    warn "No spoke mounts found in ${MOUNT_BASE}."
+    read -rp "Path to books directory: " BOOKS_PATH
+fi
+
+[ -n "$BOOKS_PATH" ] || die "Books path cannot be empty."
 [ -d "$BOOKS_PATH" ] || die "Books directory not found: $BOOKS_PATH"
 
 echo ""