#!/usr/bin/env bash
# Convert directories to btrfs subvolumes

usage() {
  echo "Usage: $0 <directory1> [directory2 ...]"
  echo "Converts each directory to a btrfs subvolume."
}

btrfs_convert() {
  local d dir tmp_dir
  for d in "$@"; do
    dir="$d"
    tmp_dir="$dir.tmp"
    if [[ ! -d "$dir" ]]; then
      echo "[ERROR] Directory '$dir' does not exist. Skipping."
      continue
    fi
    if [[ -d "$tmp_dir" ]]; then
      echo "[ERROR] Temporary directory '$tmp_dir' already exists. Skipping '$dir'."
      continue
    fi
    echo "[INFO] Creating btrfs subvolume: '$tmp_dir'..."
    if ! btrfs subvolume create "$tmp_dir" &>/dev/null; then
      echo "[ERROR] Failed to create btrfs subvolume '$tmp_dir'. Skipping '$dir'."
      continue
    fi
    echo "[INFO] Moving contents from '$dir' to '$tmp_dir'..."
    if ! mv "$dir"/* "$tmp_dir"/ 2>/dev/null; then
      echo "[ERROR] Failed to move contents from '$dir' to '$tmp_dir'. Cleaning up."
      rm -rf "$tmp_dir"
      continue
    fi
    echo "[INFO] Removing original directory '$dir'..."
    if ! rm -rf "$dir"; then
      echo "[ERROR] Failed to remove '$dir'. Manual cleanup may be required."
      continue
    fi
    echo "[INFO] Renaming '$tmp_dir' to '$dir'..."
    if ! mv "$tmp_dir" "$dir"; then
      echo "[ERROR] Failed to rename '$tmp_dir' to '$dir'. Manual cleanup may be required."
      continue
    fi
    echo "[SUCCESS] Converted '$dir' to a btrfs subvolume."
  done
}

if [[ $# -lt 1 ]]; then
  usage
  exit 1
fi

btrfs_convert "$@"