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

usage() {
  cat <<'EOF'
Usage:
  portable.sh build   [OUT_DIR] [NODE_TARBALL_URL]
  portable.sh pack    [OUT_DIR] [ARCHIVE]
  portable.sh unpack  [ARCHIVE] [OUT_DIR]

Defaults:
  OUT_DIR: codex-portable
  ARCHIVE: codex-portable.tgz
  NODE_VERSION: 20.19.6
  NODE_TARBALL_URL: auto (official if glibc >= 2.28, otherwise unofficial glibc-217)
EOF
}

cmd="${1:-}"
case "$cmd" in
  build)
    OUT_DIR="${2:-codex-portable}"
    NODE_TARBALL_URL="${3:-}"
    NODE_VERSION="${NODE_VERSION:-20.19.6}"
    TMP_DIR="${TMP_DIR:-/tmp/codex-portable-build}"

    rm -rf "$OUT_DIR" "$TMP_DIR"
    mkdir -p "$OUT_DIR" "$TMP_DIR" "$OUT_DIR/home"

    if [[ -z "$NODE_TARBALL_URL" ]]; then
      glibc_ver=""
      if command -v getconf >/dev/null 2>&1; then
        glibc_ver="$(getconf GNU_LIBC_VERSION 2>/dev/null | awk '{print $2}')"
      elif command -v ldd >/dev/null 2>&1; then
        glibc_ver="$(ldd --version 2>/dev/null | head -n1 | awk '{print $NF}')"
      fi

      if [[ -n "$glibc_ver" ]] && [[ "$(printf '%s\n' "2.28" "$glibc_ver" | sort -V | head -n1)" == "2.28" ]]; then
        NODE_TARBALL_URL="https://nodejs.org/dist/v${NODE_VERSION}/node-v${NODE_VERSION}-linux-x64.tar.xz"
      else
        NODE_TARBALL_URL="https://unofficial-builds.nodejs.org/download/release/v${NODE_VERSION}/node-v${NODE_VERSION}-linux-x64-glibc-217.tar.xz"
      fi
    fi

    echo "Downloading Node from: $NODE_TARBALL_URL"
    if command -v curl >/dev/null 2>&1; then
      curl -fL "$NODE_TARBALL_URL" -o "$TMP_DIR/node.tar.xz"
    elif command -v wget >/dev/null 2>&1; then
      wget -O "$TMP_DIR/node.tar.xz" "$NODE_TARBALL_URL"
    else
      echo "Error: need curl or wget." >&2
      exit 1
    fi

    tar -xJf "$TMP_DIR/node.tar.xz" -C "$TMP_DIR"
    node_dir="$(find "$TMP_DIR" -maxdepth 1 -type d -name 'node-v*' | head -n1)"
    if [[ -z "$node_dir" ]]; then
      echo "Error: failed to unpack Node tarball." >&2
      exit 1
    fi

    mv "$node_dir" "$OUT_DIR/node"

    echo "Installing Codex..."
    export PATH="$OUT_DIR/node/bin:$PATH"
    "$OUT_DIR/node/bin/npm" install -g --prefix "$OUT_DIR/codex" @openai/codex

    cat > "$OUT_DIR/run.sh" <<'EOF'
#!/usr/bin/env bash
set -euo pipefail

ROOT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
mkdir -p "$ROOT_DIR/home"
export HOME="$ROOT_DIR/home"
export CODEX_HOME="$ROOT_DIR/home"
export PATH="$ROOT_DIR/node/bin:$ROOT_DIR/codex/bin:$PATH"
exec "$ROOT_DIR/node/bin/node" \
  "$ROOT_DIR/codex/lib/node_modules/@openai/codex/bin/codex.js" \
  "$@"
EOF

    chmod +x "$OUT_DIR/run.sh"
    echo "Portable build ready: $OUT_DIR"
    echo "Run: $OUT_DIR/run.sh"
    ;;

  pack)
    OUT_DIR="${2:-codex-portable}"
    ARCHIVE="${3:-codex-portable.tgz}"
    if [[ ! -d "$OUT_DIR" ]]; then
      echo "Error: $OUT_DIR not found." >&2
      exit 1
    fi
    tar -czf "$ARCHIVE" -C "$(dirname "$OUT_DIR")" "$(basename "$OUT_DIR")"
    echo "Packed: $ARCHIVE"
    ;;

  unpack)
    ARCHIVE="${2:-codex-portable.tgz}"
    OUT_DIR="${3:-codex-portable}"
    if [[ ! -f "$ARCHIVE" ]]; then
      echo "Error: $ARCHIVE not found." >&2
      exit 1
    fi
    rm -rf "$OUT_DIR"
    tar -xzf "$ARCHIVE" -C "$(dirname "$OUT_DIR")"
    echo "Unpacked to: $OUT_DIR"
    ;;

  *)
    usage
    exit 1
    ;;
esac