#!/bin/bash
set -e

# verify the files exist
tmp_brew="$2"
if [[ ! -d "${tmp_brew:?}" ]]; then
    echo "no directory at $tmp_brew, exiting"
    exit 1
fi

# pick the correct target
if [[ $(uname -m) == "x86_64" ]];then
  target="/usr/local"
else
  target="/opt/Homebrew"
fi

loggedInUser=$(echo "show State:/Users/ConsoleUser" | scutil | awk '/Name :/ { print $3 }')
if [[ -f "$target/bin/brew" ]]; then
    if [[ $(sudo -u"$loggedInUser" "$target/bin/brew" developer) =~ "enabled" ]]; then
      echo "developer install, exiting"
      exit 0
    fi
    if [[ $("$tmp_brew/bin/brew" --version | head -n1) != $("$target/bin/brew" --version | head -n1) ]]; then
      echo "already an outdated install at $target, updating"
      sudo -u"$loggedInUser" "$target/bin/brew" update --auto-update
    else
      echo "already an up-to-date install at $target, exiting"
    fi
    exit 0
fi

group=$(id -gn "$loggedInUser")

install -d -o "$loggedInUser" -g "$group" "$target"
cp -RX "$tmp_brew/" "$target"

# set permissions
chown -R "$loggedInUser:$group" "$target/*"

# cleanup
rm -rf "${tmp_brew:?}/*"