vitobash

#!/bin/bash

numOfArgs=$#
arg1=$1
arg2=$2

exitScript () {
echo "End of the program"
exit 0
}

runScript () {
#   echo "The decimal number 45 is transferred into the binary representation 101101"
    number=$arg2

    case $arg1 in
        "") showPromptError ;;
        "D") convertFromDecimal ;;
        "O") convertFromOctal ;;
        "H") convertFromHexa ;;
         *)  showPromptError
    esac
}

validateArguments () {
if [[ ("$numOfArgs" = 0) ]]; then
    echo 'no arguments passed, switch to user mode'
    return 1
else
    isValid $arg1 ^[A-Za-z]+$
    isArg1Valid=$?
    isValid $arg2 ^-?[A-Za-z0-9]+$
    isArg2Valid=$?
    if [[ ! ("$numOfArgs" = 2 && $isArg1Valid = 1 && $isArg2Valid = 1 ) ]]; then
        echo 'Please pass two valid arguments'
            exitScript
    fi

    echo 'arguments passed, switching to script mode'
    return 0
fi
}

isValid () {
if [[ $1 =~ $2 ]]; then
return 1
else
return 0
fi
}

convertFromDecimal () {
isValid $number ^-?[0-9]+$
result=$?
if [ $result = 1 ]; then
    task="decimal"
    convertToBinary $number
else
    echo "Wrong decimal input"
fi
}
convertFromOctal () {
isValid $number ^[1-7][0-7]*$
result=$?
if [ $result = 1 ]; then
    task="octal"
    number=$(printf "%d\n" $number)
    convertOctalToDezimal $number
else
    echo "Wrong octal input"
fi
}
convertFromHexa () {
isValid $number ^[0-9A-Fa-f]+$
result=$?
if [ $result = 1 ]; then
    task="hexal"
    number=$(printf "%d\n" 0x$number)
    convertToBinary $number
else
    echo "Wrong hexal input"
fi
}

convertToBinary () {
local binary
local num
for((num=$number;num;num/=2))
    do
        binary=$((num%2))$binary
done

if [ $mode = 1 ]; then
printf "The binary representation is %07d\n" $binary
else
printf "The %s number %s is transferred into the binary representation %07d\n" $task $arg2 $binary
fi
}


convertOctalToDezimal () {
local dez
local num
for((num=$number;num;num/=10))
    do
        dez=$((num%8))$dez
done

if [ $mode = 1 ]; then
printf "The binary representation is \n" $dez
else
printf "The %s number %s is transferred into the binary representation \n"  $dez
fi

convertToBinary $dez

}

showPromptError () {
echo "Wrong input"
}
showPrompt () {
tasks="Decimal Octal Hexadecimal Exit";

PS3="Select one option:"
select task in $tasks
do
   case $task in
    "") showPromptError ;;
    "Decimal")
        echo "Enter the DECIMAL number you would like to transfer?"
        read number
        convertFromDecimal ;;

    "Octal")
        echo "Enter the OCTAL number you would like to transfer?"
        read number
        convertFromOctal ;;

    "Hexadecimal")
        echo "Enter the HEXADECIMAL number you would like to transfer?"
        read number
        convertFromHexa ;;

    "Exit") break ;;
     *)  break
   esac
done
}

#
# proc.sh
# Hier ist der aktuelle Einstiegspunkt des Skripts.
#

#clear
echo "Programm started"

validateArguments
mode=$?

if [ $mode = 0 ]; then
runScript
elif [ $mode = 1 ]; then
showPrompt
else
exitScript
fi

exitScript