#!/bin/bash

# The 'PostgreSQL' restore process
# ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
#
# Restore from a previously created backup

clear;

# Check to see if a backup has previously completed successfully
# If a backup is in place then carry on and restore it
if [ ! -f /home/foo/logs/postgresql_backup_created ]; then

    # Message
    echo "";
    echo -e "\e[31mNo previous backup to restore!\e[0m";

else
    # Stop the running PostgreSQL service
    echo -e "\e[1;33mStop the running PostgreSQL service...\e[0m";
    sudo systemctl stop postgresql.service;
    echo -e "\e[32mDone\e[0m";
    echo "";

    # Current PostgreSQL status
    echo -e "\e[1;33mCurrent PostgreSQL status...\e[0m";
    sudo systemctl status postgresql;
    echo -e "\e[32mDone\e[0m";
    echo "";

    # chown the existing PostgreSQL installation
    echo -e "\e[1;33mchown the existing PostgreSQL installation...\e[0m";
    sudo chown -R foo:foo /var/lib/postgresql/17/main/;
    echo -e "\e[32mDone\e[0m";
    echo "";

    # Remove the existing PostgreSQL files
    echo -e "\e[1;33mRemove the existing PostgreSQL files...\e[0m";
    sudo rm -fr /var/lib/postgresql/17/main/*;
    echo -e "\e[32mDone\e[0m";
    echo "";

    # Copy the latest backup to the PostgreSQL target location
    echo -e "\e[1;33mCopy the latest backup to the PostgreSQL target location...\e[0m";
    sudo cp -R /home/foo/backups/postgresql/* /var/lib/postgresql/17/main/;
    echo -e "\e[32mDone\e[0m";
    echo "";

    # Make the PostgreSQL user take ownership of the target location
    echo -e "\e[1;33mMake the PostgreSQL user take ownership of the target location...\e[0m";
    sudo chown -R postgres:postgres /var/lib/postgresql/17/main/;
    echo -e "\e[32mDone\e[0m";
    echo "";

    # Start the PostgreSQL service
    echo -e "\e[1;33mStart the PostgreSQL service...\e[0m";
    sudo systemctl start postgresql.service;
    echo -e "\e[32mDone\e[0m";
    echo "";

    # Current PostgreSQL status
    echo -e "\e[1;33mCurrent PostgreSQL status...\e[0m";
    sudo systemctl status postgresql;
    echo -e "\e[32mDone\e[0m";
    echo "";

fi