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

# ============================================================
# Borg 2.0.0b5 One-File Binary Builder (Variant B: without FUSE/mount)
# Target host for build: Debian 12 (Bookworm)
# Output binary: /opt/borg2-b5-build/dist/borg2-b5
# ============================================================

BORG_TAG="2.0.0b5"
VENV_DIR="/opt/borg2-b5-build"
SRC_DIR="/opt/borg-b5-src"
BIN_NAME="borg2-b5-nofuse"

if [[ $EUID -ne 0 ]]; then
  echo "[WARN] Not running as root. I will skip 'apt install'. Ensure prerequisites are installed:"
  echo "       apt install -y git python3-venv python3-dev build-essential pkg-config \\
         libssl-dev libxxhash-dev liblz4-dev libzstd-dev libacl1-dev \\
         liblzma-dev libb2-dev ca-certificates"
else
  echo "[INFO] Installing OS prerequisites via apt..."
  export DEBIAN_FRONTEND=noninteractive
  apt update -y
  apt install -y git python3-venv python3-dev build-essential pkg-config \
                 libssl-dev libxxhash-dev liblz4-dev libzstd-dev libacl1-dev \
                 liblzma-dev libb2-dev ca-certificates
fi

echo "[INFO] Creating Python venv at ${VENV_DIR} ..."
rm -rf "${VENV_DIR}"
python3 -m venv "${VENV_DIR}"
source "${VENV_DIR}/bin/activate"

echo "[INFO] Upgrading pip/setuptools/wheel and installing build helpers..."
python -m pip install -U "pip<25" "setuptools<70" wheel "Cython==0.29.36" pkgconfig "setuptools-scm<8"

echo "[INFO] Cloning Borg ${BORG_TAG} sources into ${SRC_DIR} ..."
rm -rf "${SRC_DIR}"
git clone --depth 1 --branch "${BORG_TAG}" https://github.com/borgbackup/borg.git "${SRC_DIR}"

export PKG_CONFIG_PATH="/usr/lib/x86_64-linux-gnu/pkgconfig:/usr/lib/pkgconfig:/usr/share/pkgconfig"
export BORG_CYTHONIZE=1
export BORG_OPENSSL_PREFIX="/usr"
export BORG_LIBXXHASH_PREFIX="/usr"
export BORG_LIBLZ4_PREFIX="/usr"
export BORG_LIBZSTD_PREFIX="/usr"
export BORG_LIBB2_PREFIX="/usr"
export BORG_LIBLZMA_PREFIX="/usr"
export BORG_LIBACL_PREFIX="/usr"

echo "[INFO] Removing any existing borg from venv (if present)..."
python -m pip uninstall -y borgbackup || true
rm -rf "${VENV_DIR}/lib/python3."*/site-packages/borg \
       "${VENV_DIR}/lib/python3."*/site-packages/borgbackup-"*.dist-info" \
       "${VENV_DIR}/lib/python3."*/site-packages/borg*.egg-info \
       "${VENV_DIR}/lib/python3."*/site-packages/borg*.pth \
       "${VENV_DIR}/lib/python3."*/site-packages/borg*.egg-link || true

echo "[INFO] Building & installing Borg from source (non-editable)..."
cd "${SRC_DIR}"
python -m pip install --no-build-isolation --no-cache-dir .

echo "[INFO] Import test for borg (should show version ${BORG_TAG})..."
cd /
python - <<'PY'
import borg, sys, inspect
print("borg", borg.__version__, "python", sys.version.split()[0])
print("from:", inspect.getsourcefile(borg) or borg.__file__)
PY

echo "[INFO] Creating entry stub..."
cat > "${VENV_DIR}/borg2_entry.py" <<'EOF'
import os, sys, types
os.environ.setdefault("BORG_SELFTEST", "disabled")
m = types.ModuleType("borg.selftest")
def _selftest(*a, **kw): return 0
m.selftest = _selftest
sys.modules["borg.selftest"] = m
ver = types.ModuleType("borg._version")
ver.version = "2.0.0b5"
sys.modules["borg._version"] = ver
import borg.archiver as A
if __name__ == "__main__":
    A.main()
EOF

echo "[INFO] Building one-file binary with PyInstaller (no FUSE)..."
python -m pip install "pyinstaller>=6,<7"
cd "${VENV_DIR}"
python -m PyInstaller -F -n "${BIN_NAME}" -c borg2_entry.py \
  --collect-data borg \
  --collect-binaries borg \
  --exclude-module borg.testsuite \
  --hidden-import=packaging.version \
  --hidden-import=packaging.specifiers \
  --clean -y

echo "[INFO] Build complete. Binary:"
echo "  ${VENV_DIR}/dist/${BIN_NAME}"
ls -lh "${VENV_DIR}/dist/${BIN_NAME}" || true