#!/bin/bash
set -eo pipefail
[[ $TRACE ]] && set -x

readonly DOKKU_ROOT="${DOKKU_ROOT:-/home/dokku}"
readonly DOKKU_LIB_ROOT="${DOKKU_LIB_PATH:-/var/lib/dokku}"

ps_backtrace() {
  if [ $# -lt 1 ]; then
    echo "Usage: $0 PID" >/dev/stderr
    exit 1
  fi

  declare -i pid=$1
  ppid=0
  header_modifier=""
  while :; do
    if [ $ppid -ne 0 ]; then
      header_modifier=h
    fi
    ppid=$(ps -o ppid= $pid)
    ps uww $header_modifier -p $pid
    if [ $pid -eq 1 ]; then
      break
    fi
    pid=$ppid
  done
}

main() {
  # HACK: Ensure that we only delete data when purging dokku from the system
  if ps_backtrace $BASHPID 2>/dev/null | grep dpkg | grep -- "--purge" >/dev/null; then
    echo "Processing purge"

    echo "Destroying deployed applications"
    for app in $(DOKKU_QUIET_OUTPUT=1 dokku apps:list); do
      dokku --force apps:destroy $app
    done

    # HACK: Only disable core plugins, as we don't know what data users store in non-core plugin directories
    echo "Disabling all core plugins"
    find ${DOKKU_LIB_ROOT}/core-plugins/available -mindepth 1 -maxdepth 1 -type d -printf '%f\n' | while read -r plugin; do
      if [ ! -d ${DOKKU_LIB_ROOT}/plugins/available/$plugin ]; then
        rm ${DOKKU_LIB_ROOT}/plugins/available/$plugin
        PLUGIN_PATH=${DOKKU_LIB_ROOT}/core-plugins plugn disable $plugin
        PLUGIN_PATH=${DOKKU_LIB_ROOT}/plugins plugn disable $plugin
      fi
    done
  else
    echo "Processing $1"
  fi

  dokku cleanup
}

main "$@"