add nix-stash script

files/scripts/nix_stash

@@ -0,0 +1,78 @@
+#!/bin/sh
+
+FILE_STACK_PATH="/tmp/nix_stash_stack"
+
+# pop the last line from the file-stack and return it
+pop_from_file_stack() {
+  line="$(tail -n 1 "$FILE_STACK_PATH")"
+  if [ -z "$line" ]; then
+    exit 1
+  fi
+  sed -i "$ d" "$FILE_STACK_PATH"
+  echo "$line"
+}
+
+
+do_pop() {
+  last_file="$(pop_from_file_stack)" || exit 1
+  echo "restoring $last_file"
+  trash "$last_file"
+  home-manager switch
+}
+
+
+do_stash() {
+  config_file="$(realpath --no-symlinks "$1")"
+  if [ ! -L "$config_file" ]; then
+    echo "Given file is not a symlink into the nix-store"
+    exit 1
+  fi
+
+  file_in_store="$(readlink -f "$config_file")"
+
+  if ! echo "$file_in_store" | grep -q "/nix/store"; then
+    echo "file is not a symlink into the nix store"
+    exit 1
+  fi
+
+  # remove the symlink and write the path to the stack
+  rm -rf "$config_file"
+  echo "$config_file" >> "$FILE_STACK_PATH"
+
+  # replace the file with the contents of the generated config file
+  cp -rp "$file_in_store" "$config_file"
+  chmod 777 "$config_file"
+
+  # open the file in nvim
+  "$EDITOR" "$config_file"
+}
+
+do_list() {
+  cat "$FILE_STACK_PATH"
+}
+
+print_usage() {
+  echo "usage: $0 {<filepath> | pop | list}"
+  echo "  to stash a file:   $0 <filepath>"
+  echo "  to restore a file: $0 pop"
+  echo "  list the stack:    $0 pop"
+  exit 1
+}
+
+case "$1" in
+  "")
+    print_usage
+    ;;
+  pop) 
+    do_pop 
+    ;;
+  list)
+    do_list
+    ;;
+  *) 
+    do_stash "$1" 
+    ;;
+esac
+
+
+