#!/usr/bin/env bash
set -euo pipefail

usage() {
  printf '%s\n' 'Usage: install_postgresql_storage.sh --check|--install'
}

case "${1:-}" in
  --check)
    if ! command -v psql >/dev/null 2>&1; then
      printf '%s\n' 'PostgreSQL is not installed.'
      exit 1
    fi
    psql --version
    if command -v pg_lsclusters >/dev/null 2>&1; then
      pg_lsclusters
    fi
    ;;
  --install)
    if [ "$(id -u)" -ne 0 ]; then
      printf '%s\n' 'PostgreSQL installation requires root.' >&2
      exit 1
    fi
    export DEBIAN_FRONTEND=noninteractive
    codename=''
    if [ -r /etc/os-release ]; then
      . /etc/os-release
      codename="${VERSION_CODENAME:-}"
    fi
    if [ -z "$codename" ]; then
      printf '%s\n' 'Could not determine the Ubuntu/Debian codename.' >&2
      exit 1
    fi
    if [ -x /usr/share/postgresql-common/pgdg/apt.postgresql.org.sh ]; then
      bash /usr/share/postgresql-common/pgdg/apt.postgresql.org.sh -y "$codename"
    fi
    apt-get update
    candidate="$(apt-cache policy postgresql-18 2>/dev/null || true)"
    case "$candidate" in
      *'Candidate: (none)'*|"") apt-get install -y postgresql postgresql-client ;;
      *) apt-get install -y postgresql-18 postgresql-client-18 ;;
    esac
    systemctl enable --now postgresql
    printf '%s\n' 'Native PostgreSQL installation completed.'
    psql --version
    ;;
  *)
    usage >&2
    exit 2
    ;;
esac