#!/bin/bash
### Konstanten ###

declare -A GUIDS=""
GUIDS=([ESP]="c12a7328-f81f-11d2-ba4b-00a0c93ec93b" [USR]="8484680c-9521-48c6-9c11-b0720656f69e" [USRHASH]="77ff5f63-e7b6-4633-acf4-1565b864c0e6" [ROOT]="4f68bce3-e8cd-4db1-96e7-fbcaf984b709" [SWAP]="0657fd6d-a4ab-43c4-84e5-0933c84b4f4f")

### DEFAULTS ###

DEFAULT_DEVICE="/dev/sda"
DEFAULT_NAME="ArchOS"
DEFAULT_VERSION="0.1"
DEFAULT_ESP_SIZE="512M"
DEFAULT_ESP_LABEL="EFI System Partition"
DEFAULT_SWAP_SIZE="1G"
DEFAULT_ROOT_SIZE="5G"
DEFAULT_USR_SIZE="10G"
DEFAULT_USRHASH_SIZE="1G"

### Helper ###

# shellcheck disable=SC2059 # $1 and $2 can contain the printf modifiers
out() { printf "$1 $2\n" "${@:3}"; }
error() { out "==> ERROR:" "$@"; } >&2
warning() { out "==> WARNING:" "$@"; } >&2
msg() { out "==>" "$@"; }
die() { error "${@:2}"; exit "$1"; }

### Funktionen ###

help () {
  echo "Aufruf:"
  echo " ${0##*/} [Optionen]"
  echo ""
  echo "Erstellen eines Systems mit Read-Only /usr-Baum"
  echo ""
  echo "Optionen:"
  echo " -f                  Partitionen erstellen, auch wenn sie vorhanden sind"
  echo " -d <device>         Dieses Gerät als Basis verwenden [${DEFAULT_DEVICE}]"
  echo " -v <system-version> Version des neuen Systemes [${DEFAULT_VERSION}]"
  echo " -n <name>           Name des neuen Systems [${DEFAULT_NAME}]"
  echo " -r <size>           Größe der Root-Partition [${DEFAULT_ROOT_SIZE}]"
  echo " -s <size>           Größe der Swap-Partition [${DEFAULT_SWAP_SIZE}]"
  echo " -u <size>           Größe der Usr-Partition [${DEFAULT_USR_SIZE}]"
  echo " -h                  Diese Hilfe anzeigen"
  echo ""
  echo "Exit-Code:"
  echo "  1: Ein Fehler ist aufgetreten"
  echo "  2: Üngültiges Argument"
  echo "  3: Gerät existiert nicht"
  echo " 10: Noch nicht implementiert"
  echo ""
  exit 0
}

# erase <Gerät>
erase () {
  if [[ "$#" -eq 1 ]]; then
    echo "dd if=/dev/zero of=$1 status=progress"
    #dd if=/dev/zero of="$1" status=progress
    echo "sgdisk -og $1"
    #sgdisk -og "$1"
  else
    die 1 "Kein Gerät zum Löschen angegeben"
  fi
}

# create <Type> <Gerät>
create () {
  local TYPE="$1"
  local DEVICE="$2"
  case ${TYPE} in
    "USR")
      echo "sgdisk -n 0:0:+${USR_SIZE} -t 0:${GUIDS[USR]} -c 0:${USR_LABEL} ${DEVICE}"
      #sgdisk -n 0:0:+"${USR_SIZE}" -t 0:"${GUIDS[USR]}" -c 0:"${USR_LABEL}" "${DEVICE}"
      ;;
    "ROOT")
      echo "sgdisk -n 0:0:+${ROOT_SIZE} -t 0:${GUIDS[ROOT]} -c 0:${ROOT_LABEL} ${DEVICE}"
      #sgdisk -n 0:0:+"${ROOT_SIZE}" -t 0:"${GUIDS[ROOT]}" -c 0:"${ROOT_LABEL}" "${DEVICE}"
      ;;
    "USRHASH")
      echo "sgdisk -n 0:0:+${USRHASH_SIZE} -t 0:${GUIDS[USRHASH]} -c 0:${USRHASH_LABEL} ${DEVICE}"
      #sgdisk -n 0:0:+"${USRHASH_SIZE}" -t 0:"${GUIDS[USRHASH]}" -c 0:"${USRHASH_LABEL}" "${DEVICE}"
      ;;
    "ESP")
      echo "sgdisk -n 0:0:+${ESP_SIZE} -t 0:${GUIDS[ESP]} -c 0:${ESP_LABEL} ${DEVICE}"
      #sgdisk -n 0:0:+"${ESP_SIZE}" -t 0:"${GUIDS[ESP]}" -c 0:"${ESP_LABEL}" "${DEVICE}"
      ;;
    "SWAP")
      echo "sgdisk -n 0:0:+${SWAP_SIZE} -t 0:${GUIDS[SWAP]} -c 0:${SWAP_LABEL} ${DEVICE}"
      #sgdisk -n 0:0:+"${SWAP_SIZE}" -t 0:"${GUIDS[SWAP]}" -c 0:"${SWAP_LABEL}" "${DEVICE}"
      ;;
    "TABLE")
      echo "sgdisk -og ${DEVICE}"
      #sgdisk -og "${DEVICE}"
      ;;
    *)
      die 1 "Unbekannte Partition zum Erstellen angegeben"
      ;;
  esac
}

# existing_partitions <Gerät> [<Type>]
existing_partitions () {
  local DEVICE="$1"
  local TYPE="$2"
  if [[ $# -eq 1 ]] # Genereller test auf Partitionen
  then
    ANZAHL_PARTITIONEN_VORHANDEN=$(lsblk -pl "${DEVICE}" | grep -ic "${DEVICE}[0-9]")
    if [[ ${ANZAHL_PARTITIONEN_VORHANDEN} != 0 ]]
    then
      echo "yes" # Partitionen vorhanden
    else
      echo "no" # Partitionen nicht vorhanden
    fi
  elif [[ $# -eq 2 ]] # Test auf eine bestimmte Partition
  then
    local PARTUUID="${GUIDS[${TYPE}]}" # Hier ist ein Problem
    echo "PARTUUID: ${PARTUUID}" >> temp.log
    SPEZIFISCHE_PARTITION_VORHANDEN=$(lsblk -o PARTTYPE "${DEVICE}" | grep -ic "${PARTUUID}")
    if [[ "${SPEZIFISCHE_PARTITION_VORHANDEN}" == 1 ]]
    then
      echo "yes" # bestimmte Partition vorhanden
    else
      echo "no" # bestimmte Partition nicht vorhanden
    fi
  else
    die 1 "Kein Gerät zur Prüfung auf Partitionen angegeben"
  fi
}

# find_uuid_for_partition <Gerät> <Type>
find_uuid_for_partition () {
  local DEVICE="$1"
  local TYPE="$2"
  if [[ "$(existing_partitions "${DEVICE}" "${TYPE}")" == "yes" ]]
  then
    uuid=$(lsblk -lo PARTTYPE,PARTUUID "${DEVICE}" | grep "${GUIDS[${TYPE}]}" | awk '{ print $2 }')
    echo "${uuid}"
  else
    echo "null"
  fi
}

# partitions_analyse <Gerät>
partitions_analyse () {
  local DEVICE="$1"
  local RESULT=""
  declare -i index=""
  index=0
  for type in "${!GUIDS[@]}"
  do
    index+=1
    uuid=$(find_uuid_for_partition "${DEVICE}" "${type}")
    RESULT+="${type}=${uuid}"
    if [[ "$index" != "${#GUIDS[@]}" ]]
    then
      RESULT+=" "
    fi
  done
  echo "${RESULT}"
}

# format <Gerät>
format () {
  local DEVICE="$1"
  if [[ "${FORCE}" == "yes" ]]
  then
    erase "${DEVICE}"
  fi
  
  EXISTING_PARTITIONS=$(existing_partitions "${DEVICE}")
  if [[ "${EXISTING_PARTITIONS}" == "no" ]]
  then
    create "TABLE" "${DEVICE}"
    create "ESP" "${DEVICE}"
    create "USR" "${DEVICE}"
    create "ROOT" "${DEVICE}"
    create "USRHASH" "${DEVICE}"
    create "SWAP" "${DEVICE}"
  else
    read -r -p "Partitionen überschreiben? [N/y]: " ask_overwrite
    ask_overwrite=${ask_overwrite:="n"}
    if [[ ${ask_overwrite} == [Nn] ]]
    then
      #die 10 "Noch nicht implementiert"
      ANALYSE_RESULT=$(partitions_analyse "${DEVICE}")
      if [[ "${ANALYSE_RESULT}" =~ "null"+ ]]
      then
        echo "if"
      else
        echo "else"
      fi
      #EXISTING_ESP=$(existing_partitions "${DEVICE}" "ESP")
      #if [[ "${EXISTING_ESP}" == "no" ]]
      #then
      #  create "ESP"
      #fi
    else
      erase "${DEVICE}"
      create "TABLE" "${DEVICE}"
      create "ESP" "${DEVICE}"
      create "USR" "${DEVICE}"
      create "ROOT" "${DEVICE}"
      create "USRHASH" "${DEVICE}"
      create "SWAP" "${DEVICE}"
    fi
  fi
}

### Start ###

# Optionen auslesen
while getopts :hfd:v:n:r:s:u: opt
do
  case $opt in
    h)
      help
      ;;
    f)
      FORCE="yes"
      ;;
    d)
      DEVICE="$OPTARG"
      ;;
    v)
      VERSION=$OPTARG
      ;;
    n)
      NAME=$OPTARG
      ;;
    r)
      ROOT_SIZE=$OPTARG
      ;;
    s)
      SWAP_SIZE=$OPTARG
      ;;
    u)
      USR_SIZE=$OPTARG
      ;;
    :)
      die 2 '%s: Option benötigt ein Argument -- '\''%s'\' "${0##*/}" "$OPTARG"
      ;;
    ?)
      die 2 '%s: Ungültige Option -- '\''%s'\' "${0##*/}" "$OPTARG"
      ;;
  esac
done

DEVICE=${DEVICE:="${DEFAULT_DEVICE}"}
FORCE=${FORCE:="no"}
NAME=${NAME:="${DEFAULT_NAME}"}
VERSION=${VERSION:="${DEFAULT_VERSION}"}
ESP_SIZE="${DEFAULT_ESP_SIZE}"
ESP_LABEL="${DEFAULT_ESP_LABEL}"
SWAP_SIZE=${SWAP_SIZE:="${DEFAULT_SWAP_SIZE}"}
SWAP_LABEL="${NAME} Swap"
ROOT_SIZE=${ROOT_SIZE:="${DEFAULT_ROOT_SIZE}"}
ROOT_LABEL="${NAME} Root"
USR_SIZE=${USR_SIZE:="${DEFAULT_USR_SIZE}"}
USR_LABEL="${NAME}_${VERSION}"
USRHASH_SIZE=${USRHASH_SIZE:="${DEFAULT_USRHASH_SIZE}"}
USRHASH_LABEL="${NAME}_${VERSION}"

#--------------------------------------#



#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#

echo "### DEBUG ###"
echo "DEVICE: ${DEVICE}"
echo "FORCE: ${FORCE}"
echo "NAME: ${NAME}"
echo "VERSION: ${VERSION}"
echo "ESP_SIZE: ${ESP_SIZE}"
echo "ESP_LABEL: ${ESP_LABEL}"
echo "USR_SIZE: ${USR_SIZE}"
echo "USR_LABEL: ${USR_LABEL}"
echo "USRHASH_SIZE: ${USRHASH_SIZE}"
echo "USRHASH_LABEL: ${USRHASH_LABEL}"
echo "ROOT_SIZE: ${ROOT_SIZE}"
echo "ROOT_LABEL: ${ROOT_LABEL}"
echo "SWAP_SIZE: ${SWAP_SIZE}"
echo "SWAP_LABEL: ${SWAP_LABEL}"
echo "### DEBUG ###"

#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#



#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#-#

# Prüfen, ob DEVICE existiert

#CHECK_PARTITION_EXISTENCE_OUTPUT=$(lsblk -pldo NAME | grep -ic "${DEVICE}")

#if ! lsblk -d "${DEVICE}" > /dev/null 2>&1 ; then
if [ ! -b "${DEVICE}" ]; then
  die 3 "Gerät existiert nicht, Abbruch!"
fi

# Prüfen, ob das Script mit Root-Rechten ausgeführt wird
#(( EUID == 0)) || die 3 "Dieses Script muss mit Root-Privilegien aufgerufen werden"

format "${DEVICE}"