#!/usr/bin/env bash

script_name="$(basename $(realpath $0))"
working_dir="$(dirname $(realpath $0))"

conf_file="${working_dir}/conf/${script_name%%.*}.conf"

LOCK_DIR="/tmp/$(basename $0).$$.LOCK"
log_file="${LOCK_DIR}/${script_name%%.*}.log"

CUR_IFS="$IFS"

backup_date="$(date +%Y-%m-%d-%H%M)"
declare -a files_backuped_arr=()
declare -a dirs_backuped_arr=()

# ----------
# Base Function(s)
# ----------

usage() {


   [[ -n  "$1" ]] && error "$1"


   [[ $terminal ]] && echo -e "
\033[1mUsage:\033[m

   $(basename $0)

\033[1mDescription\033[m

   The script checks whether all LX Containers configured as autostart have been 
   started. LX Containers that are not running will be started.

\033[1mOptions\033[m

   No Options

\033[1mFiles\033[m

   No Configuration File

\033[1mExample:\033[m

      $(basename $0)

"

   clean_up 1

}

clean_up() {

   # Perform program exit housekeeping
   rm -rf "$LOCK_DIR"
   blank_line
   exit $1
}


echononl(){
   if $terminal ; then
      echo X\\c > /tmp/shprompt$$
      if [ `wc -c /tmp/shprompt$$ | awk '{print $1}'` -eq 1 ]; then
         echo -e -n "   $*\\c" 1>&2
      else
         echo -e -n "   $*" 1>&2
      fi
      rm /tmp/shprompt$$
   fi
}


fatal(){
   echo ""
   if $terminal ; then
      echo -e "   [ \033[31m\033[1mFatal\033[m ] $*"
   else
      echo -e "   [ Fatal ] $*"
   fi
   echo ""
   if $terminal ; then
      echo -e "             \033[1mScript terminated\033[m.."
   else
      echo -e "             Script terminated.."
   fi
   echo ""
   rm -rf $LOCK_DIR
   exit 1
}

error (){
   echo ""
   if $terminal ; then
      echo -e "   [ \033[31m\033[1mError\033[m ] $*"
   else
      echo "   [ Error ] $*"
   fi
   echo ""
}

warn (){
   if $LOGGING || $terminal ; then
      echo ""
      if $terminal ; then
         echo -e "   [ \033[33m\033[1mWarn\033[m ]  $*"
      else
         echo "   [ Warn ]  $*"
      fi
      echo ""
   fi
}

info (){
   if $LOGGING || $terminal ; then
      echo ""
      if $terminal ; then
         echo -e "   [ \033[32m\033[1mInfo\033[m ]  $*"
      else
         echo "   [ Info ]  $*"
      fi
      echo ""
   fi
}

ok (){
   if $LOGGING || $terminal ; then
      echo ""
      if $terminal ; then
         echo -e "   [ \033[32m\033[1mOk\033[m ]    $*"
      else
         echo "   [ Ok ]    $*"
      fi
      echo ""
   fi
}

echo_done() {
   if $terminal ; then
      echo -e "\033[75G[ \033[32mdone\033[m ]"
   fi
}
echo_ok() {
   if $terminal ; then
      echo -e "\033[75G[ \033[32mok\033[m ]"
   fi
}
echo_warn() {
   if $terminal ; then
      echo -e "\033[75G[ \033[33mwarn\033[m ]"
   fi
}
echo_failed(){
   if $terminal ; then
      echo -e "\033[75G[ \033[1;31mfailed\033[m ]"
   fi
}
echo_skipped() {
   if $terminal ; then
      echo -e "\033[75G[ \033[90m\033[1mskipped\033[m ]"
   fi
}
echo_wait(){
   if $terminal ; then
      echo -en "\033[75G[ \033[5m\033[1m...\033[m ]"
   fi
}

trim() {
    local var="$*"
    var="${var#"${var%%[![:space:]]*}"}"   # remove leading whitespace characters
    var="${var%"${var##*[![:space:]]}"}"   # remove trailing whitespace characters
    echo -n "$var"
}

blank_line() {
   if $terminal ; then
      echo ""
   fi
}

containsElement () {
   local e
   for e in "${@:2}"; do [[ "$e" == "$1" ]] && return 0; done
   return 1
}

# - Backup file or directory
# -
backup() {

   is_directory=false

   if [[ -z "$1" ]] ; then
      error "No file/directory for backup given!"
      return
   elif [[ -h "$1" ]] ; then
      _source="$(realpath $1)"
      warn "'$1' is a symlink to $_source."
   elif [[ ! -d "$1" ]] && [[ ! -f "$1" ]] ; then
      warn "'$1' not found. Backup skipped."
      return
   else
      _source="$(realpath $1)"
   fi

   if [[ -d "$_source" ]]; then
      is_directory=true
      echononl "Backup directory '$_source' .."
   else
      echononl "Backup file '$_source' .."
   fi

   cp -a "$_source" "${_source}.$backup_date" > $log_file 2>&1
   if [[ $? -eq 0 ]] ; then
      echo_ok
      if $is_directory ; then
         dirs_backuped_arr+=("$_source")
      else
         files_backuped_arr+=("$_source")
      fi
   else
      echo_failed
      error "$(cat "$log_file")"
   fi
}


# - Remove script generated backups, if source wasn't changed
# -
rm_unchanged_backup() {

   if [[ ${#files_backuped_arr[@]} -gt 0 ]] ; then
      for _file in "${files_backuped_arr[@]}" ; do
         if  $(diff "$_file" "${_file}.$backup_date" > /dev/null 2>&1) ; then
            echononl "File '$(basename "${_file}")' wasn't changed.\n   Delete the previous generated backup. .."
            rm "${_file}.$backup_date" > "$log_file" 2>&1
            if [[ $? -eq 0 ]]; then
               echo_ok
            else
               echo_failed
               error "$(cat "$log_file")"
            fi
            blank_line
         fi
      done
   fi
   if [[ ${#dirs_backuped_arr[@]} -gt 0 ]] ; then
      for _dir in "${dirs_backuped_arr[@]}" ; do
         if $(diff -Nur "$_dir" "${_dir}.$backup_date" > /dev/null 2>&1) ; then
            echononl "Directory '$(basename "${_dir}")' wasn't changed.\n   Delete the previous generated backup. .."
            rm -rf "${_dir}.$backup_date" > "$log_file" 2>&1
            if [[ $? -eq 0 ]]; then
               echo_ok
            else
               echo_failed
               error "$(cat "$log_file")"
            fi
            blank_line
         fi
      done
   fi
}



# ----------
# - Jobhandling 
# ----------

# - Run 'clean_up' for signals SIGHUP SIGINT SIGTERM
# -
trap clean_up SIGHUP SIGINT SIGTERM

# - Create lock directory '$LOCK_DIR"
#
mkdir "$LOCK_DIR"


# ----------
# - Some checks ..
# ----------

# - Running in a terminal?
# -
if [[ -t 1 ]] ; then
   terminal=true
else
   terminal=false
fi

# -Is systemd supported on this system?
# -
systemd_supported=false
systemd=$(which systemd)
systemctl=$(which systemctl)

if [[ -n "$systemd" ]] && [[ -n "$systemctl" ]] ; then
   systemd_supported=true
fi

# - Print help?
# -
if [[ "$(trim $*)" = "-h" ]] || [[ "$(trim $*)" = "--help" ]] ; then
    usage
fi

if [[ -z "$(which basename)" ]]; then
   fatal 'It seems "basename" is not installed, but needed!'
fi

if [[ -z "$(which realpath)" ]]; then
   fatal 'It seems "realpath" is not installed, but needed!'
fi


# ==========
# - Begin Main Script
# ==========

# ----------
# - Headline
# ----------

if $terminal ; then
   echo ""
   echo -e "\033[1m----------\033[m"
   echo -e "\033[32m\033[1mRunning script \033[m\033[1m$script_name\033[32m .. \033[m"
   echo -e "\033[1m----------\033[m"
fi


# ----------
#  Read Configurations from $conf_file
# ----------


# - Give your default values here
# -
DEFAULT_LOGGING=false
DEFAUL_LXC_ROOT_DIR="$(realpath "/var/lib/lxc")"


if [[ -f "$conf_file" ]]; then
   source "$conf_file"
else
   if $terminal ; then
      warn "No configuration file '$conf_file' present.\n
             Loading default values.."
   fi
fi

[[ -n "$LXC_ROOT_DIR" ]] || LXC_ROOT_DIR="${DEFAUL_LXC_ROOT_DIR}"
[[ -n "$LOGGING" ]] || LOGGING="${DEFAULT_LOGGING}"


info "LX Container folder: \033[1m${LXC_ROOT_DIR}\033[m"


# ----------
# - Some pre-script tasks ..
# ----------

if $terminal ; then
   echo ""
   echo ""
   echo -e "   \033[1mDoing some pre-script tasks ..\033[m"
   echo ""
fi


declare -a lx_container_all_arr=()
declare -a lx_container_autostart_arr=()
declare -a lx_container_not_started_arr=()
declare -a error_msg_arr=()
declare -a info_msg_arr=()

echononl "Gather all configured LX-Container .."
for _container in $(lxc-ls) ; do
   lx_container_all_arr+=("$_container")
done
echo_done

#lx_container_all_arr+=("test5")
#lx_container_all_arr+=("test7")

echononl "Gather LX-Container configured as 'autostart'.."
_failed=false
for _container in ${lx_container_all_arr[@]} ; do
   if [[ ! -d "${LXC_ROOT_DIR}/${_container}" ]] ; then
      _failed=true
      if $terminal ; then
         IFS='§' error_msg_arr+=("No Container \033[1m${LXC_ROOT_DIR}/${_container}\033[m found!")
      else
         IFS='§' error_msg_arr+=("No Container '${LXC_ROOT_DIR}/${_container}' found!")
      fi
      continue
   fi
   if [[ ! -f "${LXC_ROOT_DIR}/${_container}/config" ]]; then
      _failed=true
      if $terminal ; then
         IFS='§' error_msg_arr+="No Cocnfiguration \033[1m${LXC_ROOT_DIR}/${_container}/config\033[m found!"
      else
         IFS='§' error_msg_arr+="No Cocnfiguration '${LXC_ROOT_DIR}/${_container}/config' found!"
      fi
      continue
   fi
   if $(grep -E -q "^\s*lxc.start.auto\s*=\s*1" "${LXC_ROOT_DIR}/${_container}/config" 2> $log_file) ; then
      lx_container_autostart_arr+=("$_container")
   fi
   if [[ -s "$log_file" ]] ; then
      if ! containsElement "$(cat $log_file)" "${error_msg_arr[@]}" ; then
         _failed=true
         error_msg_arr+=("")
         IFS='§' error_msg_arr+=("$(cat $log_file)")
         > $log_file
      fi
      continue
   fi


done

if $_failed ; then
   echo_failed
   if ! $terminal ; then
      echo ""
      echo "   [ Info ]  LX Container folder: '${LXC_ROOT_DIR}'"
      echo ""
      echo ""
   fi
   for _msg in ${error_msg_arr[@]} ; do
      error $_msg
   done
   for _container in ${lx_container_autostart_arr[@]} ; do
      info "Added Container \033[1m${_container}\033[m."
   done
else
   echo_done
fi

error_msg_arr=()
_failed=false
echononl "Gather LX-Container NOT started.."
for _container in ${lx_container_autostart_arr[@]} ; do
   if ! $(lxc-info -n "$_container"| grep -E -q "^\s*PID:" 2> /dev/null) ; then
      lx_container_not_started_arr+=("$_container")
   fi
   if [[ -s "$log_file" ]] ; then
      _faile=true
      error_msg_arr+=("$(cat $log_file)")
   fi
done

if $_failed ; then
   echo_failed
   for _msg in ${error_msg_arr[@]} ; do
      error $_msg
   done
else
   echo_done
fi


# ----------
# - Main part of script
# ----------

if $terminal ; then
   echo ""
   echo ""
   echo -e "   \033[1mMain part of script ..\033[m"
   echo ""
fi

if [[ ${#lx_container_not_started_arr[@]} -lt 1 ]]; then
   info "All autotart configured LX-Container are running"
   clean_up 0
fi

_falied=false
for _container in ${lx_container_not_started_arr[@]} ; do
   echononl "Goimg to start LX-Container \033[1m${_container}\033[m .."
   lxc-start -d -n $_container > $log_file 2>&1
   if [[ $? -eq 0 ]] ; then
      echo_ok
   else
      echo_failed
      _failed=true
      error "$(cat $log_file)"
   fi
done

if $_failed ; then
   clean_up 1
else
   clean_up 0
fi