#!/bin/bash
set -e # Exit immediately if a command exits with a non-zero status.

# --- 1. Set up Connection Variables ---
HOST=$POSTGRES_HOST
PORT=$POSTGRES_PORT
DB_NAME=$NEW_DB_NAME
DB_USER=$NEW_DB_USER
DB_PASSWORD=$NEW_DB_PASSWORD

# --- 2. Build the SQL Commands ---
# NOTE: The IF NOT EXISTS ensures the script can be run safely multiple times.
SQL_COMMANDS=$(cat <<-END_SQL
    -- Create user role with login and password
    DO
    \$body\$
    BEGIN
        IF NOT EXISTS (
            SELECT
            FROM   pg_catalog.pg_user
            WHERE  usename = '$DB_USER') THEN
            CREATE ROLE $DB_USER WITH LOGIN PASSWORD '$DB_PASSWORD';
        END IF;
    END
    \$body\$;

    -- Create database owned by the new user (if it doesn't exist)
    SELECT 'CREATE DATABASE $DB_NAME OWNER $DB_USER'
    WHERE NOT EXISTS (SELECT FROM pg_database WHERE datname = '$DB_NAME')\gexec
END_SQL
)

# --- 3. Execute the SQL Commands ---
echo "Attempting to connect to $HOST to execute SQL..."
echo "$SQL_COMMANDS" | psql \
    --host=$HOST \
    --port=$PORT \
    --username=$POSTGRES_ADMIN_USER \
    --dbname=postgres \
    --set ON_ERROR_STOP=on

echo "PostgreSQL database '$DB_NAME' and user '$DB_USER' created/verified successfully."