#!/bin/sh

setup(){
  if [ -z "$1" ] || [ "$1" = "--help" ] || [ "$1" = "-h" ]; then
    echo "Usage: restore filename"
    echo ""
    echo "  e.g. ./restore myBackup.zip  << Restores config from myBackup.zip"
    echo ""
    echo "Use this script to restore an openHAB configuration that was previously made with"
    echo "the openHAB 'backup' script."
    echo ""
    exit 0
  fi

  ## Ask to run as root to prevent us from running sudo in this script.
  if [ "$(id -u)" -ne 0 ]; then
    echo "Please run this script as root! (e.g. use sudo)" >&2
    exit 1
  fi

  command -v unzip >/dev/null 2>&1 || {
    echo "'unzip' program was not found, please install it first." >&2
    exit 1
  }

  ## Check to see if processes are running before restoring
  if [ ! -z "$(pgrep -f "openhab2.*java")" ]; then
    echo "openHAB is running! Please stop the process before restoring." >&2
    exit 1
  fi

  WorkingDir="$(cd "$(dirname "$0")" && cd ../.. && pwd -P)"

  ## Set path variables
  if [ -r /etc/profile.d/openhab2.sh ]; then
    . /etc/profile.d/openhab2.sh
  elif [ -r /etc/default/openhab2 ]; then
    . /etc/default/openhab2
  fi
  if [ -z "$OPENHAB_CONF" ];       then OPENHAB_CONF="$WorkingDir/conf"; fi
  if [ -z "$OPENHAB_USERDATA" ];   then OPENHAB_USERDATA="$WorkingDir/userdata"; fi

  echo "Using '$OPENHAB_CONF' as conf folder..."
  echo "Using '$OPENHAB_USERDATA' as userdata folder..."

  ## Check two of the standard openHAB folders to make sure we're updating the right thing.
  if [ ! -d "$OPENHAB_USERDATA" ] || [ ! -d "$OPENHAB_CONF" ]; then
    echo "Configuration paths are invalid..." >&2
    echo "Try setting OPENHAB_USERDATA and OPENHAB_CONF environment variables." >&2
    exit 1
  fi

  currentUser=$(ls -ld "$OPENHAB_USERDATA" | awk '{print $3}')
  currentGroup=$(ls -ld "$OPENHAB_USERDATA" | awk '{print $4}')

  CurrentVersion="$(awk '/openhab-distro/{print $3}' "$OPENHAB_USERDATA/etc/version.properties")"

  ## Store anything in temporary folders
  TempDir="/tmp/openhab2/restore"
  ## Clear older stuff if it exists
  rm -rf "${TempDir:?}"
  echo "Making Temporary Directory"
  mkdir -p "$TempDir" || {
    echo "Failed to make temporary directory: $TempDir" >&2
    exit 1
  }
}

echo "                                          "
echo "##########################################"
echo "       openHAB 2.x.x restore script       "
echo "##########################################"
echo "                                          "

InputFile="$1"

setup "$InputFile"

## Extract zip file
echo "Extracting zip file to temporary folder."

unzip -oq "$InputFile" -d "$TempDir" || {
  echo "Unable to unzip $InputFile, Aborting..." >&2
  exit 1
}

## Check for backup properties list.
if [ ! -f "$TempDir/backup.properties" ]; then
  echo "Backup was not created by openHAB scripts, please resort to a manual restore..." >&2
  exit 1
fi

## Grab information with backup.properties
str="$(awk '/version=/{print $1}' "$TempDir/backup.properties")"
BackupVersion=${str#*=}
str="$(awk '/timestamp=/{print $1}' "$TempDir/backup.properties")"
BackupTime=${str#*=}
str="$(awk '/user=/{print $1}' "$TempDir/backup.properties")"
OHUser=${str#*=}
str="$(awk '/group=/{print $1}' "$TempDir/backup.properties")"
OHGroup=${str#*=}

## Feeback to user
echo ""
echo " Backup Information:"
echo " -------------------"
echo " Backup Version         | $BackupVersion (You are on $CurrentVersion)"
echo " Backup Timestamp       | $BackupTime"
echo " Config belongs to user | $OHUser"
echo "             from group | $OHGroup"
echo ""
echo "Your current configuration will become owned by $currentUser:$currentGroup."
echo ""
echo "Any existing files with the same name will be replaced."
echo "Any file without a replacement will be deleted."
echo ""
printf "Okay to Continue? [y/N]: "
read -r answer
case "$answer" in
  [Yy]*)
    ;;
  *)
    echo "Cancelling restore..."
    rm -rf /tmp/openhab2
    exit 0
    ;;
esac

## Move old configuration
rm -rf /tmp/openhab/old
mkdir -p /tmp/openhab/old
echo "Moving system files in userdata to temporary folder"
if [ -d "$OPENHAB_USERDATA/backups" ]; then
  mv "$OPENHAB_USERDATA/backups" /tmp/openhab/old || {
    echo "Could not move backup folder to temporary folder..." >&2
    exit 1
  }
fi
if [ -d "${OPENHAB_USERDATA:?}/etc" ]; then
  mv "${OPENHAB_USERDATA:?}/etc" /tmp/openhab/old || {
    echo "Could not move etc folder to temporary folder" >&2
    exit 1
  }
fi

echo "Deleting old userdata folder..."
rm -rf "${OPENHAB_USERDATA:?}/"*

echo "Restoring system files in userdata..."
if [ -d /tmp/openhab/old/backups ]; then
  mv /tmp/openhab/old/backups "${OPENHAB_USERDATA:?}/" || {
    echo "Unable to move other backup files back..."
    exit 1
  }
fi
if [ -d /tmp/openhab/old/etc ]; then
  mv /tmp/openhab/old/etc "${OPENHAB_USERDATA:?}/" || {
    echo "Unable to move system files back..."
    exit 1
  }
fi

echo "Deleting old conf folder..."
rm -rf "${OPENHAB_CONF:?}/"*

## Restore configuration
echo "Restoring openHAB with backup configuration..."
command cp -af "$TempDir/conf/"*     "${OPENHAB_CONF:?}/" || {
  echo "Failed to copy $TempDir/conf/ to $OPENHAB_CONF/..." >&2
  echo "Please check $TempDir and replace conf and userdata." >&2
  exit 1
}
command cp -af "$TempDir/userdata/"* "${OPENHAB_USERDATA:?}/" || {
  echo "Failed to copy $TempDir/userdata/ to $OPENHAB_USERDATA/..." >&2
  echo "Please check $TempDir and replace userdata." >&2
  exit 1
}

## Reset ownership
chown -R "$currentUser:$currentGroup" "$OPENHAB_USERDATA" || {
  echo "WARNING: Failed to change userdata folder permissions to $currentUser:$currentGroup" >&2
}
chown -R "$currentUser:$currentGroup" "$OPENHAB_CONF" || {
  echo "WARNING: Failed to change conf folder permissions to $currentUser:$currentGroup" >&2
}

echo "Deleting temporary files..."
rm -rf /tmp/openhab2
echo "Backup successfully restored!"
echo ""