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

# Downloads release tarballs into ./vendor (skips existing files).
# Defaults to current stable versions; override via env:
#   GNUNET_VERSION, EXCHANGE_VERSION, MERCHANT_VERSION, LIBEUFIN_VERSION
#   GNUNET_TARBALL_URL, EXCHANGE_TARBALL_URL, MERCHANT_TARBALL_URL, LIBEUFIN_TARBALL_URL

ROOT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")/.." && pwd)"
VENDOR_DIR="${ROOT_DIR}/vendor"
mkdir -p "${VENDOR_DIR}"

# Load .env if present to honor GNUNET_TARBALL_URL/EXCHANGE_TARBALL_URL/... overrides
if [[ -f "${ROOT_DIR}/.env" ]]; then
  set -a
  # shellcheck disable=SC1091
  source "${ROOT_DIR}/.env"
  set +a
fi

GNUNET_VERSION="${GNUNET_VERSION:-0.21.2}"
EXCHANGE_VERSION="${EXCHANGE_VERSION:-1.2.2}"
MERCHANT_VERSION="${MERCHANT_VERSION:-1.1.6}"
LIBEUFIN_VERSION="${LIBEUFIN_VERSION:-1.2.3}"

# GNUnet tarball is hosted under the GNUnet mirror, Taler components under the Taler mirror.
GNUNET_URL="${GNUNET_TARBALL_URL:-https://ftp.gnu.org/gnu/gnunet/gnunet-${GNUNET_VERSION}.tar.gz}"
EXCHANGE_URL="${EXCHANGE_TARBALL_URL:-https://ftp.fau.de/gnu/taler/exchange-${EXCHANGE_VERSION}.tar.gz}"
MERCHANT_URL="${MERCHANT_TARBALL_URL:-https://ftp.fau.de/gnu/taler/merchant-${MERCHANT_VERSION}.tar.gz}"
LIBEUFIN_URL="${LIBEUFIN_TARBALL_URL:-https://ftp.fau.de/gnu/taler/libeufin-${LIBEUFIN_VERSION}.tar.gz}"

fetch() {
  local url="$1"
  local dest="${VENDOR_DIR}/$(basename "$url")"
  local name
  name="$(basename "$dest")"

  if [[ -f "$dest" ]]; then
    echo "✔ ${name} already present"
    return 0
  fi

  echo "→ Downloading ${name}"
  curl -fL "$url" -o "$dest"
}

fetch "$GNUNET_URL"
fetch "$EXCHANGE_URL"
fetch "$MERCHANT_URL"
fetch "$LIBEUFIN_URL"

echo "Done. Tarballs are in ${VENDOR_DIR}"