#!/usr/bin/env bash

# the variable UPSTREAM indicates that a standby instance is requested, otherwise this is primary
if [[ -z $UPSTREAM ]]; then

  # ensure required entries in configuration
  # shellcheck disable=SC2129
  echo "archive_command      = 'cp %p ${WAL_ARCHIVE:-/wal_archive}/%f'" >> /var/lib/postgresql/data/postgresql.conf
  echo "archive_mode         = on" >> /var/lib/postgresql/data/postgresql.conf
  echo "hot_standby          = on" >> /var/lib/postgresql/data/postgresql.conf
  echo "promote_trigger_file = '/var/lib/postgresql/data/${TRIGGER_FILE:-i_am_primary}'" >> /var/lib/postgresql/data/postgresql.conf
  echo "wal_keep_size        = ${WAL_KEEP_SIZE:-1GB}" >> /var/lib/postgresql/data/postgresql.conf
  echo "wal_level            = replica" >> /var/lib/postgresql/data/postgresql.conf
  # ensure required entries in hba
  echo "host  replication  ${REPLICATOR_NAME:-replicator}  all  md5" >> /var/lib/postgresql/data/pg_hba.conf
  # create user for replication
  psql -c "CREATE USER ${REPLICATOR_NAME:-replicator} WITH REPLICATION ENCRYPTED PASSWORD '${REPLICATOR_PASSWORD}'; GRANT CONNECT ON DATABASE postgres TO ${REPLICATOR_NAME:-replicator}"


  # process selected tweaks
  if [[ -n $MAX_CONNECTIONS ]]; then
      echo "max_connections      = ${MAX_CONNECTIONS}" >> /var/lib/postgresql/data/postgresql.conf
  fi

else
# this is a standby
  source /usr/local/bin/docker-entrypoint.sh

  docker_temp_server_stop

  rm -rf /var/lib/postgresql/data/*

  OLD_PGPASSWORD=$PGPASSWORD
  export PGPASSWORD=$REPLICATOR_PASSWORD
  pg_basebackup -h "${UPSTREAM}" -U "${REPLICATOR_NAME:-replicator}" -D "${PGDATA}" -Fp -Xs -P -R
  export PGPASSWORD=$OLD_PGPASSWORD

fi