#!/bin/bash

FILE="${@: -1}"

checkFile ()
{
if [[ ! -f "$FILE" ]]; then
  echo "File \"$FILE\" doesn't exist!"
  exit
fi
}

# User '.csv' columns
COL_USERNAME="1"
COL_FULLNAME="2"
COL_USERUID="3"
COL_USERGID="4"
COL_USERGROUPS="5"
COL_TLFN="6"
COL_EXTRAINFO="7"
COL_USERSHELL="8"
COL_USERLOCKED="9"

# Group '.csv' columns
COL_GROUPNAME="1"
COL_GROUPGID="2"

# Control variables
DRYRUN=false
FILE_CONTENTS="$(cat ${@: -1} 2>/dev/null)"
ACTION_TO_TAKE=""
DELIM=";"

usage ()
{
  echo "Usage: ./autouser.sh \$PARAMETER file.csv"
  echo ""
  echo "PARAMETERS"
  echo "    --help || -h (Show this help prompt)"
  echo "    --dry-run (Test without executing any changes)"
  echo ""
  echo "    --create-users users.csv (Create users from a .csv file)"
  echo "    --create-groups groups.csv (Create groups from a .csv file)"
  echo "    --delete-users users.csv (Delete users from a .csv file)"
  echo "    --delete-groups groups.csv (Delete groups from a .csv file)"
  echo ""
  echo "    --create-user (Create user manually)"
  echo "    --create-group (Create group manually)"
  echo "    --delete-user (Delete user manually)"
  echo "    --delete-group (Delete group manually)"
  exit
}

createGroup() {
  if [[ "$DRYRUN" == true ]]; then
    read -p "Enter group name: " GROUPNAME
    echo "groupadd $GROUPNAME"
  else
    rootCheck
    read -p "Enter group name: " GROUPNAME
    groupadd $GROUPNAME
  fi
}

createUser() {
  COMMAND="useradd -m "
  read -p "Username [Obligatory]: " USERNAME
  if [[ "$USERNAME" == "" ]]; then
    echo "Username cannot be left blank!"
    exit
  fi
  read -p "UID [Optional]: " uid
  read -p "Primary group [Optional]: " PGROUP
  read -p "Secondary groups [Optional]: " SGROUPS
  if [[ "$uid" != "" ]]; then
    COMMAND+="-u $uid "
  fi
  if [[ "$PGROUP" != "" ]]; then
    COMMAND+="-g $PGROUP "
  fi
  if [[ "$SGROUPS" != "" ]]; then
    COMMAND+="-G $SGROUPS "
  fi
  COMMAND+="$USERNAME"

  if [[ "$DRYRUN" == true ]]; then
    echo "$COMMAND"
  else
    rootCheck
    $COMMAND
  fi
}

deleteGroup() {
  COMMAND=""
  if [[ "$DRYRUN" == false ]]; then
    rootCheck
    COMMAND="groupdel"
  else
    COMMAND="echo groupdel"
  fi
    read -p "Enter group name: " GROUPNAME
    $COMMAND $GROUPNAME
}

deleteUser() {
  COMMAND=""
  if [[ "$DRYRUN" == false ]]; then
    rootCheck
    COMMAND="userdel"
  else
    COMMAND="echo userdel"
  fi
  read -p "Enter username: " USERNAME
  $COMMAND -r $USERNAME
}

rootCheck ()
{
  if [[ "$(id -u)" -ne 0 ]]; then
    echo "You must be root to run this parameter"
    exit
  fi
}

cutter ()
{
  echo "$1" | cut -d "$DELIM" -f "$2"
}

turnLowercase()
{
  echo "$1" | tr "[:upper:]" "[:lower:]" | sed 's/ñ/n/g'
}

createGroups ()
{
  checkFile
  COMMAND=""
  if [[ "$DRYRUN" == false ]]; then
    rootCheck
    COMMAND="groupadd"
  else
    COMMAND="echo groupadd"
  fi

  while read line; do
    GID=$(cutter "${line}" "$COL_GROUPGID")
    GROUPNAME=$(turnLowercase $(cutter "${line}" "$COL_GROUPNAME"))
      if [[ -z "$GID" ]]; then
        echo "[+] Adding group $GROUPNAME..."
        $COMMAND $GROUPNAME
      else
        echo "[+] Adding group $GROUPNAME with GID $GID..."
        $COMMAND $GROUPNAME -g $GID
      fi
  done <<< "$FILE_CONTENTS"
}

deleteGroups ()
{
  checkFile
  COMMAND=""
  if [[ "$DRYRUN" == false ]]; then
    rootCheck
    COMMAND="groupdel"
  else
    COMMAND="echo groupdel"
  fi

  while read line; do
    GROUPNAME=$(turnLowercase $(cutter "${line}" "$COL_GROUPNAME"))
    echo "[+] Deleting group $GROUPNAME..."
    $COMMAND $GROUPNAME
  done <<< "$FILE_CONTENTS"
}

createUsers ()
{
  checkFile
  USERADDER=""
  CHFNER=""
  USERMODDER=""
  if [[ "$DRYRUN" == false ]]; then
    rootCheck
    USERADDER="useradd"
    CHFNER="chfn"
    USERMODDER="usermod"
  else
    USERADDER="echo useradd"
    CHFNER="echo chfn"
    USERMODDER="echo usermod"
  fi

  while read line; do
    USERNAME=$(turnLowercase $(cutter "${line}" "$COL_USERNAME"))
    FULLNAME=$(cutter "${line}" "$COL_FULLNAME")
    USERUID=$(cutter "${line}" "$COL_USERUID")
    USERGID=$(turnLowercase $(cutter "${line}" "$COL_USERGID"))
    USERGROUPS=$(turnLowercase $(cutter "${line}" "$COL_USERGROUPS"))
    TLFN=$(cutter "${line}" "$COL_TLFN")
    EXTRAINFO=$(cutter "${line}" "$COL_EXTRAINFO")
    USERSHELL=$(cutter "${line}" "$COL_USERSHELL")
    USERLOCKED=$(cutter "${line}" "$COL_USERLOCKED")

    echo "[+] Adding user $USERNAME..."
    $USERADDER -m $USERNAME

    if [[ "$DRYRUN" == false ]]; then
      echo $USERNAME:$USERNAME | chpasswd
    fi

    if [[ ! -z "$FULLNAME" ]]; then
      $CHFNER -f "$FULLNAME" "$USERNAME" 1>/dev/null
    fi
    if [[ ! -z "$USERUID" ]]; then
      $USERMODDER -u $USERUID $USERNAME
    fi
    if [[ ! -z "$USERGID" ]]; then
      $USERMODDER -g $USERGID $USERNAME
    fi
    if [[ ! -z "$USERGROUPS" ]]; then
      $USERMODDER -G $(echo $USERGROUPS | tr "|" ",") $USERNAME
    fi
    if [[ ! -z "$TLFN" ]]; then
      $CHFNER -p "$TLFN" $USERNAME 1>/dev/null
    fi
    if [[ ! -z "$EXTRAINFO" ]]; then
      $CHFNER -o "$EXTRAINFO" $USERNAME 1>/dev/null
    fi
    if [[ ! -z "$USERSHELL" ]]; then
      $USERMODDER -s $USERSHELL $USERNAME
    else
      $USERMODDER -s /bin/bash $USERNAME
    fi
    if [[ $USERLOCKED == "SI" ]]; then
      $USERMODDER -L $USERNAME
    fi
  done <<< "$FILE_CONTENTS"
}

deleteUsers ()
{
  checkFile
  COMMAND=""
  if [[ "$DRYRUN" == false ]]; then
    rootCheck
    USERDELER="userdel"
    GROUPDELER="groupdel"
  else
    USERDELER="echo userdel"
    GROUPDELER="echo groupdel"
  fi
  while read line; do
    USERNAME=$(turnLowercase $(cutter "${line}" "$COL_USERNAME"))
    echo "[+] Deleting user $USERNAME..."
    $USERDELER -r $USERNAME 2>/dev/null
    $GROUPDELER $USERNAME 2>/dev/null
  done <<< "$FILE_CONTENTS"
}

for arg in "$@"
do
  if [[ "$arg" == "-h" || "$arg" == "--help" ]]; then
    usage
    exit
  fi
  if [[ "$arg" == "--dry-run" ]]; then
    DRYRUN=true
  fi
  if [[ "$arg" == "--create-groups" ]]; then
    ACTION_TO_TAKE="create-groups"
  fi
  if [[ "$arg" == "--delete-groups" ]]; then
    ACTION_TO_TAKE="delete-groups"
  fi
  if [[ "$arg" == "--create-users" ]]; then
    ACTION_TO_TAKE="create-users"
  fi
  if [[ "$arg" == "--delete-users" ]]; then
    ACTION_TO_TAKE="delete-users"
  fi
  if [[ "$arg" == "--create-group" ]]; then
    ACTION_TO_TAKE="create-group"
  fi
  if [[ "$arg" == "--create-user" ]]; then
    ACTION_TO_TAKE="create-user"
  fi
  if [[ "$arg" == "--delete-user" ]]; then
    ACTION_TO_TAKE="delete-user"
  fi
  if [[ "$arg" == "--delete-group" ]]; then
    ACTION_TO_TAKE="create-group"
  fi
done

if [[ "$ACTION_TO_TAKE" == "" ]]; then
  usage
  exit
fi

case "$ACTION_TO_TAKE" in
  create-groups)
    createGroups
    exit
    ;;
  create-users)
    createUsers
    exit
    ;;
  delete-groups)
    deleteGroups
    exit
    ;;
  delete-users)
    deleteUsers
    exit
    ;;
  create-group)
    createGroup
    exit
    ;;
  create-user)
    createUser
    exit
    ;;
  delete-group)
    deleteGroup
    exit
    ;;
  delete-user)
    deleteUser
    exit
    ;;
  *)
    echo "Invalid parameter! Exiting..."
    exit
    ;;
esac