import os
from typing import Optional

import psycopg2
from dotenv import load_dotenv

# Force reload environment variables from .env, ignoring system vars.
load_dotenv(override=True)

DB_HOST = os.getenv("DB_HOST")
DB_PORT = os.getenv("DB_PORT")
DB_NAME = os.getenv("DB_NAME")
DB_USER = os.getenv("DB_USER")
DB_PASSWORD = os.getenv("DB_PASSWORD")


def connect_to_pgsql() -> Optional[psycopg2.extensions.connection]:
    """Establish a connection to the PostgreSQL database."""
    try:
        return psycopg2.connect(
            host=DB_HOST,
            port=DB_PORT,
            database=DB_NAME,
            user=DB_USER,
            password=DB_PASSWORD,
            # Set the client encoding to UTF-8.
            options="-c client_encoding=utf8",
        )
    except psycopg2.Error as exc:
        print(f"Error connecting to PostgreSQL database: {exc}")
        return None