bash studies task 2

#!/usr/bin/env bash
#Template created by Artsiom Dziavitski
#################OOOOOOOOOOOOOOOOOOOOOOOOOO################
export LANG=ru_RU.UTF-8

#Env block#
LOCKFILE="/tmp/script.lock"
GRPLIST="test_group my_group lalala_group" ##First group will be primary, other is secondary
SUSERNAME="super_user"
USERSCOUNT=5
USERTMPLT="test"

#COLORS
RED='\033[0;31m'
GREEN='\033[0;32m'
BLUE='\033[0;36m'
NC='\033[0m' # No Color

#ALIAS
shopt -s expand_aliases
alias echo="echo -e"
alias red_echo="echo '${RED}'"
alias green_echo="echo '${GREEN}'"
alias blue_echo="echo '${BLUE}'"
alias nocolor_echo="echo '${NC}'"
###########

#Func block#
#
func_create_lock_file () {
##############################
local path="$1"
##############################
if [ -f /usr/bin/lockfile ]
then {
    lockfile "${path}"
}
else {
    touch "${path}"
    chmod 444 "${path}"
}
fi
if [ "$?" -gt "0" ]
then {
    red_echo "Lockfile ${path} not created. May be script already started"
    nocolor_echo
    exit 1001
    }
fi
}
func_check_lock_file () {
#execution: func_check_lock_file ${LOCKFILE}
##############################
local path="$1"
##############################
if [ -f "${path}" ]
then {
    red_echo "Lockfile already exist."
    nocolor_echo
    exit 100
    }
else {
    blue_echo "Creating lockfile."
    nocolor_echo
    func_create_lock_file ${LOCKFILE}
    }
fi
}
func_delete_lock_file () {
#execution: func_delete_lock_file ${LOCKFILE}
##############################
local path="$1"
##############################
if [ -f "${path}" ]
then {
    rm -f "${path}"
    #ls -al ${path}
}
else {
    red_echo "Lockfile ${path} not found."
    nocolor_echo
    exit 102
}
fi
}
#
#

func_hello () {

blue_echo "Скрипт с 3 заданиями"
blue_echo "Для запуска задания необходимо запустить скрипт с параметром task1, или task2, или task3. Так же можно удалить файл блокировки запустив скрипт с параметром rmlock."
nocolor_echo
}

func_template () {
echo "${BLUE} Ambassador: This is MADNESS!!!! ${NC} O_o"
echo "${RED} Leonidas:    NO! THIS IS SPARDAAAAAAAA!!!!!!!  (┛ò__ó)┛ ${NC}"
}

func_isroot () {
##############################
    local usr=""
##############################
    usr="$(whoami)"
    if [ "${usr}" != "root" ]
    then {
        red_echo "User $usr is not root. Please use sudo to run this script."
        nocolor_echo
        func_delete_lock_file ${LOCKFILE}
        exit 200
    }
    else {
        blue_echo "You have root permissions. All ok."
        nocolor_echo
    }
    fi


}

func_addgrp () {
##############################
    local grp=""
##############################
    for grp in $1
    do
        groupadd "$grp"
    done
}

func_rmgrp () {
##############################
    local grp=""
##############################
    for grp in $1
    do
        groupdel "$grp"
    done
}

func_addsuperuser () {
##############################
    local supername="$1"
##############################
    useradd --create-home "${supername}"
    if grep -Fq "${supername}" /etc/sudoers
    then {
        echo "${supername} access to sudo was allredy granted"
    }
    else {
        echo "${supername}    ALL=(ALL:ALL) NOPASSWD:ALL" >> /etc/sudoers
    }
    fi
    echo "ADDED SUPERUSER:"
    echo " ______________________________________________________";echo "|   USERNAME   |         HOMEDIR       |      SHELL    |"; echo "|------------------------------------------------------|"
    grep "${supername}" /etc/passwd | cut -d ':' -f1,6,7|sed "s/:/   |    /g" | sed "s/^/| /" | sed "s/$/  |/"
    echo "--------------------------------------------------------";
}

func_rmsuperuser () {
##############################
    local supername="$1"
##############################
    sed -i "/$supername/d" /etc/sudoers
    /usr/sbin/userdel --remove "$supername" 2>/dev/null
    blue_echo "User ${supername} deleted"
    nocolor_echo
}


func_addusers () {
##############################
    local numberof=$1
    local tmplt_name="$2"
    local tmplt_comm="test user"
    local tmplt_pass="password"
    local tmplt_primg=""
    local tmplt_secg=""
    local count="1"
##############################
    tmplt_primg="$(echo "$GRPLIST"| awk '{ print $1 }')"
    tmplt_secg="$(echo "$GRPLIST"| cut -d ' ' -f2- |sed 's/ /,/g' )"
    while [ "$count" -le "$numberof" ]
    do
        sudo -u $SUSERNAME -s <<EOF
                    sudo /usr/sbin/useradd --create-home --gid "$tmplt_primg" --groups "$tmplt_secg" --comment "${tmplt_comm}" "$tmplt_name""$count"
EOF
        echo "$tmplt_name""$count":"$tmplt_pass" | /usr/sbin/chpasswd 2>/dev/null
        ((count++))
    done

    echo "ADDED USERS:"
    echo " _____________________________________________________________";echo "|USERNAME |     COMMENT    |      HOMEDIR     |     SHELL     |"; echo "|-------------------------------------------------------------|"
    grep "${tmplt_name}" /etc/passwd | cut -d ':' -f1,5,6,7|sed "s/:/   |    /g" | sed "s/^/| /" | sed "s/$/  |/"
    echo "---------------------------------------------------------------";
}

func_rmusers () {
##############################
    local numberof=$1
    local tmplt_name="$2"
    local count="1"
##############################
    while [ "$count" -le "$numberof" ]
    do
        blue_echo "User ""$tmplt_name""$count deleted."
        nocolor_echo
        /usr/sbin/userdel --remove "$tmplt_name""$count" 2>/dev/null
        #let "count++"
        ((count++))
    done
}

func_filemanipulations () {
##############################
    local numberof=$1
    local tmplt_name="$2"
    local superfile=""
    local userfile=""
    local fileline=""
    local homedir=""
    local username=""
    local user_secgrp=""
##############################

    homedir="$(grep $SUSERNAME /etc/passwd|cut -d ":" -f 6)"
    sudo -u $SUSERNAME -s <<EOF
    dd if=/dev/zero of="${homedir}/_file" bs=1024 count=100 2>/dev/null
EOF
    echo "CREATED FILES"
    echo " _________________________________________________________________________________________";echo "|         FILEPATH         |  SIZE Kb  |      OWNER      |     GROUP     |   PERMISSIONS  |"; echo "|-----------------------------------------------------------------------------------------|"
    ls --block-size=k -al "${homedir}/_file" | awk -v OFS=':' '{print $9, $5, $3, " "$4"  ", $1}'|sed "s/:/   |    /g"| sed "s/^/| /" | sed "s/$/  |/"
    superfile="${homedir}/_file"
    homedir=""
    fileline="$(grep "${tmplt_name}" /etc/passwd)"
#   echo "File manipulations STAGE2"
    while read -r homedir
    do
        username="$(echo "${homedir}"| cut -d ":" -f 1)"
        user_secgrp="$(grep "${username}" /etc/group | head -n 1 | cut -d ":" -f 1)"
        homedir="$(echo "${homedir}"| cut -d ":" -f 6)"
        userfile="${homedir}/$(basename "${superfile}")"
        cp -f "${superfile}" "${userfile}"
        chown "${username}:${user_secgrp}" "${userfile}"
        chmod 345 "${userfile}"

    ls -al --block-size=k "${userfile}"| awk -v OFS=':' '{print $9"     ", $5, "  "$3"   ", $4, $1}'|sed "s/:/   |    /g"| sed "s/^/| /" | sed "s/$/  |/"
    done <<< "$fileline"
    echo "-------------------------------------------------------------------------------------------"
}

func_shellchange () {
##############################
    local trueuser=""
    local stringnum=""
    local line=""
##############################
    trueuser="$(who am i | awk '{print $1}')"
    echo "trueuser is: ${trueuser}"

####sed#####
    cp -f /etc/passwd /root/passwd.copy
    stringnum="$(grep -n "${trueuser}" /root/passwd.copy|head -n 1| awk -F ':' '{print $1}')"
    echo "stringnum is: ${stringnum}"
    echo "Before SED:"
    grep "${trueuser}" /root/passwd.copy
    sed -i "${stringnum}s/bash/sh/g" /root/passwd.copy
    echo "After SED:"
    grep "${trueuser}" /root/passwd.copy
    echo "===================================================================================================="
###awk######
   red_echo  "A TUTA4KI S AWK JA NE PRIDUMAL KAK NATIVNO ZAMENIT STROKU. ¯\_(ツ)_/¯ . NADO BUDET AWK PODU4IT."
   nocolor_echo
    cp -f /etc/passwd /root/passwd.copy
    awk -v pro="${trueuser}" '{FS = ":"} {OFS = ":"} {if($1==pro) {gsub(/bash/,"sh",$7); print}}' /root/passwd.copy
   echo "===================================================================================================="
###bash#####
    cp -f /etc/passwd /root/passwd.copy
    cat /dev/null > /root/passwd.copy_t
    while read -r line
    do
        if [ "$(echo "${line}" | grep -c "${trueuser}" )" -eq 1 ]
        then {
            echo "${line/bash/sh}" >> /root/passwd.copy_t
        }
        else {
            echo "${line}" >> /root/passwd.copy_t
        }
        fi
    done < /root/passwd.copy
    echo "Before BASH:"
    grep "${trueuser}" /root/passwd.copy
    mv /root/passwd.copy_t /root/passwd.copy
    echo "After BASH:"
    grep "${trueuser}" /root/passwd.copy
    echo "===================================================================================================="
rm -f /root/passwd.copy
}

func_killall () {
##############################
    local procname=""
    local pids=""
    local pid=""
##############################

    if [ -z "${procname}" ]
    then {
        echo "Enter process name to kill"
        read -r procname
            if [ -z "${procname}" ]
                then {
                    echo "no process name to kill. Exit"
                    exit 0
                }
                else {
                    echo "Your process name to kill is: ${procname}"
                    pids="$(ps a |awk -v pro="${procname}" '{FS = " "} {if($5==pro) {print $1}}')"
                    if [ ! -z "${pids}" ]
                    then {
                    for pid in ${pids}
                    do
                    echo "Your process id to kill is: ${pid}"
                    kill -9 "${pid}"
                    done
                    }
                    else {
                    echo "No running process with name ${procname} to kill."
                    }
                    fi
                }
                fi
    }
    else {
        echo "process name to kill is: ${procname}"
    }
    fi
}

############
#func_delete_lock_file ${LOCKFILE}

####BEGIN####


#func_template

case $1 in

task1)
func_check_lock_file ${LOCKFILE}
func_isroot
func_shellchange
func_delete_lock_file ${LOCKFILE}
;;

task2)
func_check_lock_file ${LOCKFILE}
func_isroot
func_addgrp "$GRPLIST"
func_addsuperuser "$SUSERNAME"
func_addusers "${USERSCOUNT}" "${USERTMPLT}"
func_filemanipulations "${USERSCOUNT}" "${USERTMPLT}"
func_rmusers "${USERSCOUNT}" "${USERTMPLT}"
func_rmsuperuser ${SUSERNAME}
func_rmgrp "$GRPLIST"
func_delete_lock_file ${LOCKFILE}

;;
task3)
func_check_lock_file ${LOCKFILE}
func_killall
func_delete_lock_file ${LOCKFILE}
;;
rmlock)
func_delete_lock_file ${LOCKFILE}
;;
*)
func_hello
;;
esac

exit 0
#####END#####