#!/bin/sh

# local backup
# Dotfiles are shared across machines, so no fixed device or path names:
# the target is whichever mounted /mnt/*/backup directory exists; failing
# that, a closed LUKS partition is opened and mounted under /mnt, named
# after its filesystem label (mount_luks sets $luks_mount accordingly).
luks_mount=""
backup_path=""
dot_path="${XDG_DOTFILES_DIR:-${HOME}/.dotfiles}"
git_path="$HOME/Private/repos"
pass_path="${PASSWORD_STORE_DIR:-${XDG_DATA_HOME:-${HOME}/.local/share}/.password-store}/exported_keys"
suck_path="${XDG_SOURCES_HOME:-${HOME}/.local/src}/suckless"
user_home=$(eval echo ~"$USER")

# targets
bash_path="${XDG_DOTFILES_DIR:-${HOME}/.dotfiles}/ar/.config/bash"
shell_path="${XDG_DOTFILES_DIR:-${HOME}/.dotfiles}/ar/.config/shell"
vim_path="${XDG_DOTFILES_DIR:-${HOME}/.dotfiles}/ar/.config/vim"
thesiah_path="${THESIAH_WWW:-${HOME}/Private/repos/THESIAH}/public"
lf_path="${XDG_DOTFILES_DIR:-${HOME}/.dotfiles}/ar/.config/lf"

usage() {
  echo "Synchronize files and save them in backup path."
  echo ""
  echo "Usage: ${0##*/} [OPTIONS]"
  echo ""
  echo "Options:"
  echo "  -h, --help      Show this help message"
  echo "  -r, --root      Sync root files only"
  echo ""
  echo "Example:"
  echo "  ${0##*/}             # Sync all files to backup path"
  echo "  ${0##*/} --root      # Sync root files only"
  exit 0
}

error() {
  printf "%s\n" "$1" >&2
  exit 1
}

# First existing backup/ directory on a mounted drive under /mnt wins.
find_backup_path() {
  for _dir in /mnt/*/backup; do
    [ -d "$_dir" ] || continue
    mountpoint -q "${_dir%/backup}" 2>/dev/null || continue
    printf '%s' "$_dir"
    return 0
  done
  return 1
}

# Closed LUKS partition = crypto_LUKS fstype without an opened crypt child.
# Device names differ across machines and boots, so detect by type instead
# of hardcoding paths. Prints the largest candidate, if any.
find_closed_luks() {
  lsblk -prbno PATH,FSTYPE,SIZE 2>/dev/null |
    awk '$2 == "crypto_LUKS" { print $3, $1 }' |
    sort -rn |
    while read -r _size _dev; do
      lsblk -rno TYPE "$_dev" 2>/dev/null | grep -qx "crypt" && continue
      printf '%s\n' "$_dev"
      break
    done
}

# Open the LUKS partition and mount it under /mnt. The mount point follows
# the inner filesystem's label (same convention as the other /mnt/<label>
# drives); "second" is only a fallback for unlabeled filesystems.
mount_luks() {
  _device="$1"
  ${TERMINAL:-st} -n floatterm -g 60x1 -e sudo cryptsetup open "$_device" "second"
  [ -e /dev/mapper/second ] || return 1
  _label="$(lsblk -rno LABEL /dev/mapper/second 2>/dev/null | head -n 1)"
  luks_mount="/mnt/${_label:-second}"
  sudo -A mkdir -p "$luks_mount"
  sudo -A mount "/dev/mapper/second" "$luks_mount" -o uid="$(id -u)",gid="$(id -g)" 2>/dev/null || sudo -A mount "/dev/mapper/second" "$luks_mount"
}

# Using a loop over space-separated strings instead of an array
sync_files() {
  # top-level targets go directly under the backup path
  for source in "$git_path" "$pass_path"; do
    rsync -vrazPlu --exclude=".music.txt" --delete "$source" "$backup_path/" >/dev/null 2>&1 || {
      echo "Failed to sync $(basename "$source")"
    }
  done

  # dotfiles and suckless are stored under repos/
  [ -d "$backup_path/repos" ] || mkdir -p "$backup_path/repos"
  for source in "$dot_path" "$suck_path"; do
    rsync -vrazPlu --exclude=".music.txt" --delete "$source" "$backup_path/repos/" >/dev/null 2>&1 || {
      echo "Failed to sync $(basename "$source")"
    }
  done
}

sync_root() {
  # clean targets
  sudo rm -rf /root/.config /root/.bash_history /root/.local/share/history
  sudo mkdir -p /root/.config/bash /root/.config/lf /root/.config/shell /root/.config/vim /root/.local/bin /root/.local/share/history/vim_history /root/.local/state

  # Root configuration synchronization on local system
  sudo rsync -vrazPlu --delete "$vim_path/vimrc" "/root/.config/vim/" >/dev/null 2>&1
  sudo rsync -vrazPlu --delete "$lf_path" "/root/.config/" >/dev/null 2>&1
  sudo mv -f "/root/.config/lf/rooticons" "/root/.config/lf/icons" >/dev/null 2>&1
  sudo rsync -vrazPlu --delete "$bash_path" "/root/.config/" >/dev/null 2>&1
  sudo rsync -vrazPlu --delete "$shell_path/inputrc" "/root/.config/shell/" >/dev/null 2>&1

  # load shortcuts
  shortcuts >/dev/null 2>&1

  # Modify root's Bash and LF configuration to include user-specific settings
  echo "[ -f \"$user_home/.config/shell/shortcutrc\" ] && source \"$user_home/.config/shell/shortcutrc\"" | sudo tee -a /root/.config/bash/bashrc >/dev/null 2>&1
  echo "[ -f \"$user_home/.config/shell/zshnameddirrc\" ] && source \"$user_home/.config/shell/zshnameddirrc\"" | sudo tee -a /root/.config/bash/bashrc >/dev/null 2>&1
  sudo sed -i "s|source[[:space:]]*\"\?~/.config/lf/shortcutrc\"\?|source \"$user_home/.config/lf/shortcutrc\"|" /root/.config/lf/lfrc >/dev/null 2>&1
  sudo grep -q "source \"\?/root/.config/lf/rootshortcutrc\"\?" /root/.config/lf/lfrc ||
    sudo sed -i "\|source \"\?$user_home/.config/lf/shortcutrc\"\?|a source \"/root/.config/lf/rootshortcutrc\"" /root/.config/lf/lfrc

  # Final ownership and link adjustments
  sudo chown -R root:root /root/.config/ >/dev/null 2>&1
  sudo ln -sf /root/.config/bash/bashrc /root/.bashrc >/dev/null 2>&1
  sudo ln -sf /root/.config/bash/bash_profile /root/.bash_profile >/dev/null 2>&1
  sudo ln -sf /root/.config/shell/inputrc /root/.inputrc >/dev/null 2>&1
  sudo ln -sf /root/.config/vim/vimrc /root/.vimrc >/dev/null 2>&1
}

sync_server() {
  # clean targets
  ssh "$THESIAH_SERVER" "rm -rf /root/.config /var/www/thesiah"
  ssh "$THESIAH_SERVER" "mkdir -p /root/.config/bash /root/.config/shell /root/.config/vim /root/.local/bin /root/.local/share /root/.local/state /var/www/thesiah"

  # Sync operations with explicit error checking
  cd "$THESIAH_WWW" || return 1
  [ -d "$thesiah_path" ] || hugo --cleanDestinationDir
  rsync -vrazPlu --delete "$thesiah_path/" "$THESIAH_SERVER:/var/www/thesiah/" >/dev/null 2>&1 && rm -rf "$thesiah_path"
  rsync -vrazPlu --delete "$vim_path/vimrc" "$THESIAH_SERVER:/root/.config/vim/" >/dev/null 2>&1
  rsync -vrazPlu --delete "$shell_path/inputrc" "$THESIAH_SERVER:/root/.config/shell/" >/dev/null 2>&1
  sudo cp /root/.config/shell/rootshortcutrc ~/.cache/
  sudo chown -R "$USER":wheel ~/.cache/rootshortcutrc
  rsync -vrazPlu --remove-source-files "$HOME/.cache/rootshortcutrc" "$THESIAH_SERVER:/root/.config/shell/" >/dev/null 2>&1

  # Adding custom shortcuts to root's shell configuration on the remote system
  ssh "$THESIAH_SERVER" "echo 'web=\"cd /var/www && ls -A\" \\' >> /root/.config/shell/rootshortcutrc"
  ssh "$THESIAH_SERVER" "echo 'wen=\"cd /var/www/nextcloud && ls -A\" \\' >> /root/.config/shell/rootshortcutrc"
  ssh "$THESIAH_SERVER" "echo 'wep=\"cd /var/www/prosody && ls -A\" \\' >> /root/.config/shell/rootshortcutrc"
  ssh "$THESIAH_SERVER" "echo 'wet=\"cd /var/www/thesiah && ls -A\" \\' >> /root/.config/shell/rootshortcutrc"
  ssh "$THESIAH_SERVER" "echo 'gng=\"cd /etc/nginx/sites-available && ls -A\" \\' >> /root/.config/shell/rootshortcutrc"

  # Sync Bash configuration
  rsync -vrazPlu --delete "$bash_path" "$THESIAH_SERVER:/root/.config/" >/dev/null 2>&1
  ssh "$THESIAH_SERVER" "chown -R root:root /var/www/thesiah"
  ssh "$THESIAH_SERVER" "chown -R root:root /root/.config/"
  ssh "$THESIAH_SERVER" "ln -sf /root/.config/bash/bash_profile /root/.profile"
  ssh "$THESIAH_SERVER" "source /root/.profile"

  # Sync for Git
  ssh "$THESIAH_SERVER" "cp -r /root/.config /var/www/git/"
  ssh "$THESIAH_SERVER" "chown -R git:git /var/www/git/.config/"
  ssh "$THESIAH_GIT" "ln -sf /var/www/git/.config/bash/bash_profile /var/www/git/.profile"
  ssh "$THESIAH_GIT" "source /var/www/git/.profile"
}

sync_nextcloud() {
  base="$(basename "$backup_path")"
  parent="$(dirname "$backup_path")"
  tmpdir="$(mktemp -d)"
  cd "$tmpdir" || return 1
  tar -C "$parent" -zcf "$base".tar.gz "$base" >/dev/null 2>&1
  rsync -vrazPlu --delete "$tmpdir/$base".tar.gz "$THESIAH_SERVER:/var/www/nextcloud/data/si@thesiah.xyz/files/backup/" >/dev/null 2>&1
  ssh "$THESIAH_SERVER" "chown -R www-data:www-data /var/www/nextcloud/data/si@thesiah.xyz/files/backup" >/dev/null 2>&1
  ssh "$THESIAH_SERVER" "cd /var/www/nextcloud && sudo -u www-data ./occ files:scan --path="/si@thesiah.xyz/files"" >/dev/null 2>&1
  rm -r "$tmpdir"
}

handle_long_option() {
  case $1 in
  help)
    usage
    ;;
  root)
    echo "Sync root files..."
    sync_root && echo "Success to sync root!" && echo "Done!" || error "Failed to back up root"
    exit 0
    ;;
  *)
    error "Unknown option: --$1"
    ;;
  esac
}

process_options() {
  while [ $# -gt 0 ]; do
    case $1 in
    -h | --help)
      usage
      ;;
    -r | --root)
      echo "Sync root files..."
      sync_root && echo "Success to sync root!" && echo "Done!" || error "Failed to back up root"
      exit 0
      ;;
    --*)
      handle_long_option "${1#--}"
      ;;
    -*)
      error "Unknown option: $1"
      ;;
    *)
      break
      ;;
    esac
    shift
  done
}

# Start script
echo "Backup starts..."
process_options "$@"

# Main script logic
# Resolve the backup target: an existing /mnt/*/backup directory first,
# then a closed LUKS partition as fallback.
backup_available=false
if backup_path="$(find_backup_path)"; then
  backup_available=true
  echo "Backup target found: $backup_path"
else
  echo "No /mnt/*/backup directory found"
  luks_device="$(find_closed_luks)"
  if [ -n "$luks_device" ]; then
    echo "Attempting to mount LUKS drive $luks_device..."
    if mount_luks "$luks_device" && mountpoint -q "$luks_mount" 2>/dev/null; then
      backup_path="$luks_mount/backup"
      backup_available=true
      echo "Success to mount luks drive!"
    else
      echo "Backup drive not available. Skipping file backup..."
    fi
  else
    echo "No closed LUKS partition found either. Skipping file backup..."
    echo "(mark a drive as backup target once: mkdir /mnt/<drive>/backup)"
  fi
fi

# Sync home files only if backup drive is available
if [ "$backup_available" = true ]; then
  [ -d "$backup_path" ] || sudo mkdir -p "$backup_path"
  echo "Sync home files..." && sync_files && echo "Success to sync files!" || echo "Warning: Failed to sync some files"
else
  echo "Skipping home files sync (no backup drive)"
fi

echo "Sync root files..." && sync_root && echo "Success to sync root!" || echo "Warning: Failed to sync root"

# Sync server files only if the server is reachable without prompting;
# otherwise each of the many ssh/rsync calls in sync_server would ask for
# a password in turn.
server_available=false
if [ -n "$THESIAH_SERVER" ]; then
  if ssh -o BatchMode=yes -o ConnectTimeout=5 "$THESIAH_SERVER" true >/dev/null 2>&1; then
    server_available=true
    echo "Sync server files..." && sync_server && echo "Success to sync server!" || echo "Warning: Failed to sync server"
  else
    echo "Warning: $THESIAH_SERVER not reachable via non-interactive ssh. Skipping server sync..."
  fi
else
  echo "Skipping server sync (THESIAH_SERVER not set)"
fi

# Sync to nextcloud only if both backup drive and server are available
if [ "$backup_available" = true ] && [ "$server_available" = true ]; then
  echo "Sync files to nextcloud..." && sync_nextcloud && echo "Success to sync nextcloud!" || echo "Warning: Failed to sync nextcloud"
fi

echo "Done!"