#!/usr/bin/env bash

# Strict execution
set -o errexit
set -o nounset
set -o pipefail

# Load PPAS environment
source "/opt/PostgresPlus/9.5AS/pgplus_env.sh"
export PGPASSWORD=""

# General configuration
declare -A cfg
cfg['directory']="/tmp"
cfg['format']="custom"
cfg['suffix']="$(date +%Y%m%d%H%M)"

# Log configuration
declare -A log
log['directory']="/var/log/support/ppas"
log['file']="${log['directory']}/$(basename "${BASH_SOURCE[0]%.*}").log"

# External backup configuration
declare -A storage
storage['active']="0"
storage['directory']=""
storage['host']=""
storage['user']=""

# Redirect output to log['file'] and stdout
exec &> >(tee -a "${log['file']}")

# Add current timestamp to the logs
echo "$(date)"

# Usage function
function usage() {
  echo -n "$(basename $0) [OPTION]...
PostgreSQL backup script
Options:
    -d <database>   Backup <database>
    -h              Display this help and exit
"
}

# Backup function
function backup() {
    echo "Saving database ${1}" "${1}"
    pg_dump --format="${cfg['format']}" --username=postgres --host="127.0.0.1" --port=5432 --password "${1}" | gzip > "${cfg['directory']}/${1}${cfg['suffix']}.${cfg['format']}.gz"
    echo "Database successfully saved to ${cfg['directory']}/${1}${cfg['suffix']}.${cfg['format']}.gz"

    # If external storage is active, send the backup to it
    if [[ "${storage['active']}" -eq 1 ]]; then
        scp "${cfg['directory']}/${1}${cfg['suffix']}.${cfg['format']}.gz" "${storage['user']}@${storage['host']}:${storage['directory']}"
    fi
}

# Display usage if no arguments were passed
if [[ "${#}" -eq 0 ]]; then
    usage
    exit 0
fi

# If arguments were passed, parse them
while getopts "d:h" parameter; do
    case "${parameter}" in
        d) backup "${OPTARG}" ;;
        h) usage && exit 0 ;;
        \?) usage && exit 0 ;;
    esac
done