#!/usr/bin/env bash
# 007-postgres-admin-role - Make the iwanhae Linux user a PostgreSQL
# superuser so it can administer the cluster via peer auth (psql with no
# password, like the postgres OS user). Requires 006 (cluster running).
# up:   CREATE ROLE iwanhae LOGIN SUPERUSER (idempotent; re-run promotes)
# down: DROP ROLE iwanhae (with hint if it owns objects in some database)
set -euo pipefail

ROLE=iwanhae

role_exists() {
  runuser -u postgres -- psql -v ON_ERROR_STOP=1 -tAc \
    "SELECT 1 FROM pg_roles WHERE rolname='$ROLE'" | grep -q 1
}

case "${1:-}" in
  up)
    if role_exists; then
      runuser -u postgres -- psql -v ON_ERROR_STOP=1 -qc \
        "ALTER ROLE $ROLE WITH LOGIN SUPERUSER"
      echo "    role $ROLE already existed - promoted to LOGIN SUPERUSER"
    else
      runuser -u postgres -- psql -v ON_ERROR_STOP=1 -qc \
        "CREATE ROLE $ROLE WITH LOGIN SUPERUSER"
      echo "    role $ROLE created: LOGIN SUPERUSER"
    fi
    # end-to-end proof: connect over the unix socket as the OS user (peer)
    check=$(runuser -u "$ROLE" -- psql -d postgres -tAc \
      "SELECT current_user || ' (superuser=' || rolsuper || ')' FROM pg_roles WHERE rolname = current_user")
    echo "    peer-auth check: $check"
    ;;
  status)
    if [[ $EUID -eq 0 ]]; then
      q() { runuser -u postgres -- psql -d postgres -v ON_ERROR_STOP=1 -tAc "$1"; }
    elif psql -d postgres -tAc 'SELECT 1' >/dev/null 2>&1; then
      q() { psql -d postgres -v ON_ERROR_STOP=1 -tAc "$1"; }
    else
      echo "? needs root or peer DB access to verify"
      exit 2
    fi
    row=$(q "SELECT rolsuper::text || '/' || rolcanlogin FROM pg_roles WHERE rolname='$ROLE'")
    [[ -n $row ]] || { echo "DRIFT role $ROLE does not exist"; exit 1; }
    [[ $row == true/true ]] || { echo "DRIFT role $ROLE super/login=$row (want true/true)"; exit 1; }
    echo "OK role $ROLE exists: superuser + login"
    ;;
  down)
    if role_exists; then
      if runuser -u postgres -- psql -v ON_ERROR_STOP=1 -qc "DROP ROLE $ROLE"; then
        echo "    role $ROLE dropped"
      else
        echo "cannot drop $ROLE - it owns objects. In EVERY database it has objects run:" >&2
        echo "  runuser -u postgres -- psql -d <db> -c 'DROP OWNED BY $ROLE;'" >&2
        exit 1
      fi
    else
      echo "    role $ROLE does not exist - nothing to do"
    fi
    ;;
esac