#!/usr/bin/env bash
set -euo pipefail

ENV_FILE="${ENV_FILE:-./.env}"
if [[ -f "$ENV_FILE" ]]; then
  set -a
  # shellcheck source=/dev/null
  . "$ENV_FILE"
  set +a
fi

if [[ -z "${DATABASE_URL:-}" ]]; then
  echo "DATABASE_URL is required."
  exit 1
fi

if [[ -z "${EXPECTED_PROD_DB_HOST:-}" || -z "${EXPECTED_PROD_DB_NAME:-}" ]]; then
  echo "EXPECTED_PROD_DB_HOST and EXPECTED_PROD_DB_NAME are required."
  exit 1
fi

extract_host() {
  local url="$1"
  sed -E 's#^[a-zA-Z][a-zA-Z0-9+.-]*://[^@/]+@([^/:?]+).*$#\1#' <<< "$url"
}

extract_db() {
  local url="$1"
  sed -E 's#^[a-zA-Z][a-zA-Z0-9+.-]*://[^/]+/([^?]+).*$#\1#' <<< "$url"
}

ACTUAL_HOST="$(extract_host "$DATABASE_URL")"
ACTUAL_DB="$(extract_db "$DATABASE_URL")"

if [[ "$ACTUAL_HOST" == "$DATABASE_URL" || "$ACTUAL_DB" == "$DATABASE_URL" ]]; then
  echo "Unable to parse DATABASE_URL."
  exit 1
fi

if [[ "$ACTUAL_HOST" != "$EXPECTED_PROD_DB_HOST" ]]; then
  echo "DATABASE_URL host mismatch. expected=$EXPECTED_PROD_DB_HOST actual=$ACTUAL_HOST"
  exit 1
fi

if [[ "$ACTUAL_DB" != "$EXPECTED_PROD_DB_NAME" ]]; then
  echo "DATABASE_URL db mismatch. expected=$EXPECTED_PROD_DB_NAME actual=$ACTUAL_DB"
  exit 1
fi

echo "DATABASE_URL target check passed (host=$ACTUAL_HOST db=$ACTUAL_DB)."