#!/usr/bin/env bash

set -e

VOLUME_PATH=/Volumes/installer
while getopts ":d:h" opts; do
  case $opts in
    d)
      VOLUME_PATH=$OPTARG
      ;;
    h)
      echo "Usage: $0 [-h] [-d disk] name"
      echo "name is either mojave, mojave_beta, or catalina_beta"
      echo "    -h Show this help message"
      echo "    -d /Volumes path to where it makes a bootable disk."
      echo "       If it doesn't exist, it will create a disk image."
      exit 0
      ;;
  esac
done
readonly VOLUME_PATH

shift $((OPTIND - 1))
readonly NAME=$1

if [[ $(dirname "$VOLUME_PATH") != "/Volumes" ]]; then
  echo "Invalid volume path '$VOLUME_PATH'" >&2
  exit 1
fi

case $NAME in
  mojave)
    INSTALL_APP_PATH="/Applications/Install macOS Mojave.app"
    MAC_APP_STORE_ID="id1398502828"
    ;;
  mojave_beta)
    INSTALL_APP_PATH="/Applications/Install macOS Mojave Beta.app"
    MAC_APP_STORE_ID="id1354523149"
    REQUIRE_ENROLL=1
    ;;
  catalina)
    INSTALL_APP_PATH="/Applications/Install macOS Catalina.app"
    MAC_APP_STORE_ID="id1466841314"
    ;;
  catalina_beta)
    INSTALL_APP_PATH="/Applications/Install macOS Catalina Beta.app"
    MAC_APP_STORE_ID="id1455661060"
    REQUIRE_ENROLL=1
    ;;
  *)
    echo "Unknown name '$NAME'. See usage by give -h." >&2
    exit 1
    ;;
esac
readonly INSTALL_APP_PATH
readonly MAC_APP_STORE_ID
readonly REQUIRE_ENROLL

if [[ -r "$INSTALL_APP_PATH/Contents/SharedSupport/InstallESD.dmg" ]]; then
  echo "Found the install app, create an install disk."
  if [[ ! -e $VOLUME_PATH ]]; then
    readonly DISK_IMAGE_NAME=$(basename "$VOLUME_PATH")

    echo "Creating a disk image '$DISK_IMAGE_NAME'"

    # Mojave, Catalina install disk image requires about 7GB space.
    hdiutil create -o "$DISK_IMAGE_NAME.dmg" -volname "$DISK_IMAGE_NAME" -size 7G -layout SPUD -fs HFS+J && \
    hdiutil attach "$DISK_IMAGE_NAME.dmg"
  fi

  # Create an install disk.
  sudo "$INSTALL_APP_PATH/Contents/Resources/createinstallmedia" \
  --volume "$VOLUME_PATH" \
  --downloadassets
else
  if ((REQUIRE_ENROLL)); then
    echo "Enroll developer seed and open Mac App Store."
    echo "You can unenroll after downloading the install app by next command:"
    echo "sudo /System/Library/PrivateFrameworks/Seeding.framework/Versions/A/Resources/seedutil unenroll"

    # Tell Mac App Store that we've enrolled `DeveloperSeed`.
    # Actual `enroll` is needed to download a complete install image from Mac App Store.
    sudo /System/Library/PrivateFrameworks/Seeding.framework/Versions/A/Resources/seedutil enroll DeveloperSeed
    /usr/libexec/PlistBuddy -c "clear dict" -c "add :SeedProgram string DeveloperSeed" /Users/Shared/.SeedEnrollment.plist
  fi

  # Open Mac App Store to download macOS installer app.
  /usr/bin/open "macappstores://itunes.apple.com/app/$MAC_APP_STORE_ID"

  echo "Click Get on Mac App Store to download installer app, then run this script again to create an install disk image."
fi