#!/usr/bin/env bash
set -Eeuo pipefail
IFS=$'\n\t'

log()      { printf '%s\n' "$*"; }
log_err()  { printf 'ERR: %s\n' "$*" >&2; }

usage() {
  cat <<'USG'
Usage: db_check.sh
Env:
  DATABASE_URL or PGHOST/PGPORT/PGDATABASE/PGUSER/PGPASSWORD
USG
}

command -v psql >/dev/null 2>&1 || { log_err "psql not found"; exit 127; }

if [[ -n "${DATABASE_URL:-}" ]]; then
  PSQL_ARGS=("$DATABASE_URL")
else
  : "${PGHOST:?PGHOST required or set DATABASE_URL}"
  : "${PGDATABASE:?PGDATABASE required or set DATABASE_URL}"
  PSQL_ARGS=("host=$PGHOST" "port=${PGPORT:-5432}" "dbname=$PGDATABASE" "user=${PGUSER:-postgres}")
fi

SQL=$(cat <<'SQL'
\timing on
SELECT 'atomic_facts_total' AS metric, count(*) AS value FROM atomic_facts
UNION ALL
SELECT 'by_category:' || category, count(*) FROM atomic_facts GROUP BY category ORDER BY 1;
SQL
)

psql "${PSQL_ARGS[@]}" -At -c "$SQL" | awk -F'|' '{ printf("%s: %s\n", $1, $2) }'