20049393cw2p2

#!/bin/bash
if [[ $# == 2 && $1 =~ ^[A-Za-z]+$ && $2 =~ ^[0-9]+$ ]]
        then
                secretKey=pass557
                retries=3
                echo "Please enter a secret key to run the program:-"
                read inputKey
                while [[ $inputKey != $secretKey && $retries -gt 0 ]]
                do
                        echo "Please enter a correct secret key to run the program. Retries left:- $retries"
                                read inputKey
                        retries=$((retries-1))
                done
                if [ $retries -le 0 ]
                then
                        exit
                fi
        echo "Welcome $2, $1"
        echo at `date +"%Y-%m-%d %T"`

        answer=yes
        while [ $answer == "yes" ]
        do
        Bands(){
                echo "|-------------------|------------------|"
                echo "|      BANDS        |       CODE       |"
                echo "|-------------------|------------------|"
                echo "|      Beatles      |       BEA        |"
                echo "|      AC/DC        |       AD         |"
                echo "|      Queen        |       QUE        |"
                echo "|      Blondie      |       BLO        |"
                echo "|      Nirvana      |       NIR        |"
                echo "|--------------------------------------|"
                echo "Choose the best music band by their designated code."
        }
        Band_Code_Selection(){
                read bandCode
                until [[ $bandCode == "AD" ]];
                do
                        echo "Wrong guess. Please choose the correct band code from the list below:-"
                        Bands
                        read bandCode
                done
                        echo "AC/DC is an Australian rock band founded by Scottish-born brothers Malcolm and Angus Young. Hard rock, blues rock, and heavy metal have all been used to characterize its sound, but the band simply refers to it as rock and roll."
        }
                Bands
                Band_Code_Selection
        Artists(){
                echo
                echo "Choose three best musical artists in the world from the list below with their designated code."
                echo
                echo "|-------------------|-------------------|"
                echo "|       ARTISTS     |        CODE       |"
                echo "|-------------------|-------------------|"
                echo "|     John Lennon   |         JL        |"
                echo "|     Angus Young   |         AY        |"
                echo "|  Freddie Mercury  |         FM        |"
                echo "|    Debby Harry    |         DH        |"
                echo "|    Kurt Cobain    |         KC        |"
                echo "|---------------------------------------|"
                echo
                echo
                echo "Format: artist_code_1 artist_code_2 artist_code_3"
                echo "e.g. JL AY FM"
        }
        Reloop_Program(){
                echo "Do you want to run the program again? (yes/no)"
                read answer
                if [ $answer = yes ]
                then
                        Bands
                        Band_Code_Selection
                        Artists
                        Artist_Selection
                        Reloop_Program
                else
                        exit
                fi
        }
        Artist_Selection(){
        # Artists
        read a1 a2 a3
        artists=($a1 $a2 $a3)
        if [[ -z $a1 || -z $a2 || -z $a3 ]]
        then
                echo "Empty Field."
        elif [[ ${#artists[@]} -gt 3 ]]
        then
                echo "More than 3 arguments"
        elif [[ "$a1" == "$a2" || "$a1" == "$a3" || "$a2" == "$a3" ]]
        then
                echo "Same code entered more than once."
        else
                echo "Select one number from the above code:-"
        select a in $a1 $a2 $a3
                do
                        if [ "$a" = "JL" ]
                        then
                                cat JL
                                break
                        elif [ "$a" = "FM" ]
                        then
                                cat FM
                                break
                        elif [ "$a" = "KC" ]
                        then
                                cat KC
                                break
                        elif [[ -z $a ]]
                        then
                                echo "Invalid option chosen! Please try once again."
                                Artists
                                Artist_Selection
                                break
                        else
                                echo "Wrong choice. No external file found. Redirected to the Band selection screen."
                                Bands
                                Band_Code_Selection
                                Artists
                                Artist_Selection
                                Reloop_Program
                        fi
                done
        fi
        }
        Artists
        Artist_Selection
        Reloop_Program
        done
else
        echo "Wrong Format"
        echo "Correct Format:- bash cw2p2 student's_first_name id"
        echo "e.g bash cw2p2 Baibhab 20049393"
fi