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

if [[ "$(uname -s)" != "Darwin" ]]; then
  echo "This installer is for macOS only."
  exit 1
fi

if ! command -v curl >/dev/null 2>&1; then
  echo "curl is required but not installed."
  exit 1
fi

if ! command -v unzip >/dev/null 2>&1; then
  echo "unzip is required but not installed."
  exit 1
fi

workdir="$(mktemp -d)"
mounted_dmg=""
mount_point=""
cleanup() {
  if [[ -n "$mount_point" && -d "$mount_point" ]]; then
    # Prefer detaching by the known mount path; force as a fallback to avoid stale mounts.
    hdiutil detach "$mount_point" >/dev/null 2>&1 || hdiutil detach -force "$mount_point" >/dev/null 2>&1 || true
  elif [[ -n "$mounted_dmg" ]]; then
    hdiutil detach "$mounted_dmg" >/dev/null 2>&1 || hdiutil detach -force "$mounted_dmg" >/dev/null 2>&1 || true
  fi
  rm -rf "$workdir"
}
trap cleanup EXIT

zip_path="$workdir/Mac_OSX_VCP_Driver.zip"
extract_dir="$workdir/extracted"

mkdir -p "$extract_dir"

echo "Downloading Silicon Labs CP210x macOS driver..."
curl -fL "https://www.silabs.com/documents/public/software/Mac_OSX_VCP_Driver.zip" -o "$zip_path"

echo "Extracting package..."
unzip -q "$zip_path" -d "$extract_dir"

pkg_path="$(find "$extract_dir" -type f -name "*.pkg" | head -n 1)"

if [[ -z "$pkg_path" ]]; then
  dmg_path="$(find "$extract_dir" -type f -name "*.dmg" | head -n 1)"

  if [[ -n "$dmg_path" ]]; then
    mount_point="$workdir/mnt"
    mkdir -p "$mount_point"

    echo "Mounting disk image..."
    hdiutil_output="$(hdiutil attach -nobrowse -readonly -mountpoint "$mount_point" "$dmg_path")"
    mounted_dmg="$(printf '%s\n' "$hdiutil_output" | awk '/Apple_HFS|APFS/ {print $NF}' | head -n 1)"

    if [[ -z "$mounted_dmg" ]]; then
      mounted_dmg="$mount_point"
    fi

    pkg_path="$(find "$mount_point" -type f -name "*.pkg" | head -n 1)"
  fi
fi

if [[ -z "$pkg_path" ]]; then
  echo "No .pkg installer found in downloaded archive or mounted disk image."
  exit 1
fi

echo "Installing package (administrator password may be required)..."
echo "When prompted, type in your password. The password will not be shown as you type - this is normal. Just type and press enter."
sudo installer -pkg "$pkg_path" -target /

echo "CP210x macOS driver installation completed."
echo "If prompted by macOS security settings, approve the system extension and reboot if required."