#!/usr/bin/env bash

set -u

TARGET="berity"
ASSUME_YES=0
DRY_RUN=0
REMOVED_ANY=0

usage() {
  cat <<'EOF'
Usage:
  uninstall-berity.sh [--yes] [--dry-run] [target_name]

Examples:
  ./uninstall-berity.sh
  ./uninstall-berity.sh --yes
  ./uninstall-berity.sh --dry-run berity
EOF
}

log() {
  printf '%s\n' "$*"
}

run() {
  if [ "$DRY_RUN" -eq 1 ]; then
    printf '[DRY-RUN] %q ' "$@"
    printf '\n'
    return 0
  fi
  "$@"
}

run_root() {
  if [ "$(id -u)" -eq 0 ]; then
    run "$@"
  else
    run sudo "$@"
  fi
}

is_cmd() {
  command -v "$1" >/dev/null 2>&1
}

parse_args() {
  while [ "$#" -gt 0 ]; do
    case "$1" in
      --yes|-y)
        ASSUME_YES=1
        ;;
      --dry-run|-n)
        DRY_RUN=1
        ;;
      --help|-h)
        usage
        exit 0
        ;;
      *)
        TARGET="$1"
        ;;
    esac
    shift
  done
}

confirm() {
  if [ "$ASSUME_YES" -eq 1 ]; then
    return 0
  fi
  printf 'This will uninstall "%s" and clean common leftovers. Continue? [y/N] ' "$TARGET"
  read -r answer
  case "$answer" in
    y|Y|yes|YES) return 0 ;;
    *) return 1 ;;
  esac
}

remove_file_if_exists() {
  local path="$1"
  if [ -e "$path" ] || [ -L "$path" ]; then
    log "[remove] $path"
    run_root rm -rf "$path" && REMOVED_ANY=1
  fi
}

uninstall_apt() {
  is_cmd apt-get || return 0
  local pkg
  for pkg in "$@"; do
    if dpkg -s "$pkg" >/dev/null 2>&1; then
      log "[apt] removing $pkg"
      run_root apt-get remove --purge -y "$pkg" && REMOVED_ANY=1
    fi
  done
}

uninstall_dnf_or_yum() {
  local pkg mgr
  if is_cmd dnf; then
    mgr="dnf"
  elif is_cmd yum; then
    mgr="yum"
  else
    return 0
  fi
  for pkg in "$@"; do
    if is_cmd rpm && rpm -q "$pkg" >/dev/null 2>&1; then
      log "[$mgr] removing $pkg"
      run_root "$mgr" remove -y "$pkg" && REMOVED_ANY=1
    fi
  done
}

uninstall_pacman() {
  is_cmd pacman || return 0
  local pkg
  for pkg in "$@"; do
    if pacman -Q "$pkg" >/dev/null 2>&1; then
      log "[pacman] removing $pkg"
      run_root pacman -Rns --noconfirm "$pkg" && REMOVED_ANY=1
    fi
  done
}

uninstall_zypper() {
  is_cmd zypper || return 0
  local pkg
  for pkg in "$@"; do
    if is_cmd rpm && rpm -q "$pkg" >/dev/null 2>&1; then
      log "[zypper] removing $pkg"
      run_root zypper --non-interactive rm "$pkg" && REMOVED_ANY=1
    fi
  done
}

uninstall_snap() {
  is_cmd snap || return 0
  local pkg
  for pkg in "$@"; do
    if snap list 2>/dev/null | awk '{print $1}' | grep -Fxq "$pkg"; then
      log "[snap] removing $pkg"
      run_root snap remove "$pkg" && REMOVED_ANY=1
    fi
  done
}

uninstall_flatpak() {
  is_cmd flatpak || return 0
  local pkg
  for pkg in "$@"; do
    if flatpak list --app --columns=application 2>/dev/null | grep -Fxq "$pkg"; then
      log "[flatpak user] removing $pkg"
      run flatpak uninstall -y "$pkg" && REMOVED_ANY=1
    fi
    if flatpak list --system --app --columns=application 2>/dev/null | grep -Fxq "$pkg"; then
      log "[flatpak system] removing $pkg"
      run_root flatpak uninstall --system -y "$pkg" && REMOVED_ANY=1
    fi
  done
}

uninstall_pip() {
  local pkg
  if is_cmd pip3; then
    for pkg in "$@"; do
      if pip3 show "$pkg" >/dev/null 2>&1; then
        log "[pip3] removing $pkg"
        run pip3 uninstall -y "$pkg" && REMOVED_ANY=1
      fi
    done
  fi
  if is_cmd python3; then
    for pkg in "$@"; do
      if python3 -m pip show "$pkg" >/dev/null 2>&1; then
        log "[python3 -m pip] removing $pkg"
        run python3 -m pip uninstall -y "$pkg" && REMOVED_ANY=1
      fi
    done
  fi
}

uninstall_npm() {
  is_cmd npm || return 0
  local pkg
  for pkg in "$@"; do
    if npm -g ls --depth=0 "$pkg" >/dev/null 2>&1; then
      log "[npm global] removing $pkg"
      run npm -g uninstall "$pkg" && REMOVED_ANY=1
    fi
  done
}

remove_systemd_units() {
  is_cmd systemctl || return 0
  local unit
  for unit in "$@"; do
    if systemctl list-unit-files 2>/dev/null | awk '{print $1}' | grep -Fxq "$unit"; then
      log "[systemd] disabling/stopping $unit"
      run_root systemctl disable --now "$unit" || true
      REMOVED_ANY=1
    fi
  done
}

main() {
  parse_args "$@"

  local packages=(
    "$TARGET"
    "${TARGET}-cli"
    "${TARGET}-agent"
    "${TARGET}-desktop"
    "com.${TARGET}.app"
  )

  local units=(
    "${TARGET}.service"
    "${TARGET}-agent.service"
    "${TARGET}-server.service"
  )

  if ! confirm; then
    log "Cancelled."
    exit 1
  fi

  uninstall_apt "${packages[@]}"
  uninstall_dnf_or_yum "${packages[@]}"
  uninstall_pacman "${packages[@]}"
  uninstall_zypper "${packages[@]}"
  uninstall_snap "${packages[@]}"
  uninstall_flatpak "${packages[@]}"
  uninstall_pip "${packages[@]}"
  uninstall_npm "${packages[@]}"

  remove_systemd_units "${units[@]}"

  remove_file_if_exists "/usr/local/bin/$TARGET"
  remove_file_if_exists "/usr/bin/$TARGET"
  remove_file_if_exists "$HOME/.local/bin/$TARGET"
  remove_file_if_exists "/etc/systemd/system/${TARGET}.service"
  remove_file_if_exists "/etc/systemd/system/${TARGET}-agent.service"
  remove_file_if_exists "/opt/$TARGET"
  remove_file_if_exists "/etc/$TARGET"
  remove_file_if_exists "/var/lib/$TARGET"
  remove_file_if_exists "/var/log/$TARGET"
  remove_file_if_exists "$HOME/.${TARGET}"
  remove_file_if_exists "$HOME/.config/$TARGET"
  remove_file_if_exists "$HOME/.cache/$TARGET"
  remove_file_if_exists "$HOME/.local/share/$TARGET"

  if is_cmd systemctl; then
    run_root systemctl daemon-reload || true
  fi

  if command -v "$TARGET" >/dev/null 2>&1; then
    log
    log "Uninstall attempted, but '$TARGET' is still on PATH: $(command -v "$TARGET")"
    exit 2
  fi

  if [ "$REMOVED_ANY" -eq 1 ]; then
    log
    log "Uninstall completed for target '$TARGET'."
  else
    log
    log "Nothing found to remove for target '$TARGET'."
  fi
}

main "$@"