Morse

#!/bin/bash
# Filename: morse.sh
# Version.: 01102017
# Author..: robz
# Training aid to print out and recite morse code in a terminal.
# Get stuff "sudo apt install espeak"

tabs="\n"
code=(A .- B -... C -.-. D -.. E . F ..-. G --. H .... I .. J .--- K -.- \
L .-.. M -- N -. O --- P .--. Q --.- R .-. S ... T - U ..- V ...- W .-- X -..- \
Y -.-- Z --.. 1 .---- 2 ..--- 3 ...-- 4 ....- 5 ..... 6 -.... 7 --... 8 ---.. \
9 ----. 0 ----- stop .-.-.- comma --..-- query ..--..)

trap 'kill -9 $pid 2>/dev/null; exit' TERM EXIT

for character in {0..78..2}; do
    echo -ne "$tabs ${code[character]}\t"
    espeak -a 400 "${code[character]}"
    tput bold
    while read -n1 dotdash; do
        [ "$dotdash" = "." ] && duration="0.2" || duration="0.4"
        echo -n "$dotdash"
        (speaker-test -t sine -f 400 >/dev/null) & pid="$!";\
        sleep "$duration"; kill -9 "$pid"
    done < <(echo -n "${code[((character+1))]}")
    tput sgr0
    [ "$tabs" = "\n" ] && tabs="\t|\t" || tabs="\n"
    sleep 1
done 2> /dev/null
echo -e "\n\nEnd of morse code demo.\n"

exit