Key signature function from I_scare_children's beeper player

#determines flats/sharps based on the key
#contains 12 functions;
#dependens on: variables_from_input_commands
key_signature () {

#functions for each symbol of the key signature (in the order of the circle of fifths)
    fis () {
        if [ "$base_pitch" == "F" -a "$acc" == "" ]; then
        acc="#"
        fi
    }

    cis () {
        if [ "$base_pitch" == "C" -a "$acc" == "" ]; then
        acc="#"
        fi
    }

    gis () {
        if [ "$base_pitch" == "G" -a "$acc" == "" ]; then
        acc="#"
        fi
    }

    dis () {
        if [ "$base_pitch" == "D" -a "$acc" == "" ]; then
        acc="#"
        fi
    }

    ais () {
        if [ "$base_pitch" == "A" -a "$acc" == "" ]; then
        acc="#"
        fi
    }

    eis () {
        if [ "$base_pitch" == "E" -a "$acc" == "" ]; then
        acc="#"
        fi
    }

    b   () {
        if [ "$base_pitch" == "H" -a "$acc" == "" ]; then
        acc="b"
        fi
    }

    es () {
        if [ "$base_pitch" == "E" -a "$acc" == "" ]; then
        acc="b"
        fi
    }

    as () {
        if [ "$base_pitch" == "A" -a "$acc" == "" ]; then
        acc="b"
        fi
    }

    des () {
        if [ "$base_pitch" == "D" -a "$acc" == "" ]; then
        acc="b"
        fi
    }

    ges () {
        if [ "$base_pitch" == "G" -a "$acc" == "" ]; then
        acc="b"
        fi
    }

    ces () {
    if [ "$base_pitch" == "C" -a "$acc" == "" ]; then
    acc="b"
    fi
}

case $key in #assigning appropriate symbols to the key
    G|e|D|h|A|"f#"|"f #"|E|"c#"|"c #"|H|"g#"|"g #"|"F#"|"F #"|"d#"|"d #")
        fis
        case $key in
            D|h|A|"f#"|"f #"|E|"c#"|"c #"|"c #"|H|"g#"|"g #"|"F#"|"F #"|"d#"|"d #")
                cis
            case $key in
                A|"f#"|"f #"|E|"c#"|"c #"|H|"g#"|"g #"|"F#"|"F #"|"d#"|"d #")
                    gis
                case $key in
                    E|"c#"|"c #"|H|"g#"|"g #"|"F#"|"F #"|"d#"|"d #")
                        dis
                    case $key in
                        H|"g#"|"g #"|"F#"|"F #"|"d#"|"d #")
                            ais
                        case $key in
                            "F#"| "F #"|"d#"|"d #")
                                eis
                                ;;
                        esac
                    esac
                esac
            esac
        esac
    ;;
    F|d|B|Hb|g|"Eb"|"E b"|c|"Ab"|"A b"|f|"Db"|"D b"|"Hb"|"h b"|"Gb"|"G b"|"eb"|"e b")
        b
        case $key in
        B|Hb|g|"Eb"|"E b"|c|"Ab"|"A b"|f|"Db"|"D b"|"hb"|"h b"|"Gb"|"G b"|"eb"|"e b")
            es
            case $key in
            "Eb"|"E b"|c|"Ab"|"A b"|f|"Db"|"D b"|"hb"|"h b"|"Gb"|"G b"|"eb"|"e b")
                as
                case $key in
                "Ab"|"A b"|f|"Db"|"D b"|"hb"|"h b"|"Gb"|"G b"|"eb"|"e b")
                    des
                    case $key in
                    "Db"|"D b"|"hb"|"h b"|"Gb"|"G b"|"eb"|"e b")
                        ges
                        case $key in
                        "Gb"|"G b"|"eb"|"e b")
                            ces
                        esac
                    esac
                esac
            esac
        esac
esac
}