if [ "${BASH_SOURCE[0]}" == "${0}" ]
then
clear
stty -echo
echo 'Functions and descriptions:

menu()
Press Up and Down Arrows to move up and down
Press Enter to select

Paramerters:
menu [title] [options]
menu {string} {string...}

Example:
menu "Choose An Option:" "Option A" "Option B" "Option C"
case $output in
1) functionA;;
2) functionB;;
3) functionC;;
esac



fullscreen()
Asks user to fullscreen the terminal
When they fullscreen, it continues the program

Parameters:
fullscreen
fullscreen

Example:
fullscreen



index()
Gets the index of an item in an array named "array"

Parameters:
index [item]
index {string}

Example:
array=("itemA" "itemB" "itemC")
item=${array[$(($RANDOM % ${#array[@]}))]}
index=$(index "$item")
echo "Item ${index[0]} in the array is '\$item'"



encode()
Encodes a string with an integer passkey
Can only encode lowercase letters

Parameters:
encode [message] [passkey] ["-string" or "-integer"] [custom cipher]
encode {string} {integer or string} {flag} {array}

Example:
read plaintext
read passkey
encode "$plaintext" "$passkey" -string



decode()
Deocdes a string with an integer passkey
Only decodes into lowercase letters

Parameters:
decode [encoded message] [passkey] ["-string" or "-integer"] [custom cipher]
decode {string} {integer or string} {flag} {array}

Example:
read ciphertext
read passkey
decode "$ciphertext" "$passkey" -string'
read
stty echo
fi
menu() {
clear
printf "\e[1m$1\n"
options=("${@:2}")
chars=()
for i in ${!options[@]}
do
option=${options[i]}
new_option=""
chars+=(${#option})
for (( n=0; n<${#option}; n++ ))
do
if [ "${option:n:1}" = "_" ]
then
new_option="$new_option "
else
new_option="$new_option${option:n:1}"
fi
done
printf "\e[0m$new_option\n"
done
menu=1
while true
do
tput cup $menu ${chars[$((menu - 1))]}
read -sn3 read
case "$read" in
$'\e[A')
if [ $menu = 1 ]
then
menu=${#options[@]}
else
((menu--))
fi
;;
$'\e[B')
if [ $menu = ${#options[@]} ]
then
menu=1
else
((menu++))
fi
;;
"")
output=$menu
return
esac
done
}
fullscreen() {
tput smcup
while [ $(tput cols) -lt 200 ] && [ $(tput lines) -lt 60 ]
do
clear
echo "Please fullscreen the terminal"
echo "Status: Window"
sleep 0.1
done
clear
echo "Status: Fullscreen"
echo "Press enter to continue"
stty -echo
read
stty echo
}
index() {
index=()
for i in ${!array[@]}
do
if [ "${array[$i]}" == "$1" ]
then
index+=($i)
fi
done
echo ${index[@]}
}
encode() {
if [ "$4" != "" ]
then
array=($4)
else
array=(- 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)
fi
cipher=()
plain=$1
if [ "$3" == "-string" ] || [[ "$2" =~ [^0-9] ]]
then
key=0
for i in $(seq ${#2})
do
index=$(index ${2:i-1:1})
if [ "${index[@]}" != "" ]
then
key=$(echo "$key+${index[0]}*${#array[@]}^($i-1)" | bc)
fi
done
else
key=$2
fi
if [ "$3" == "-integer" ] && [[ "$2" =~ [^0-9] ]]
then
key=0
fi
for i in $(seq ${#plain})
do
if [ "${plain:$i-1:1}" == " " ]
then
index=0
else
index=$(index ${plain:$i-1:1})
fi
if [ "${index[@]}" == "" ]
then
cipher=(0 ${cipher[@]})
else
cipher=($(echo ${index[0]}*$key | bc) ${cipher[@]})
fi
done
out=""
i=0
while [ ${cipher[$i]} -gt 0 ] || [ $i -lt ${#plain} ]
do
((i++))
mod=$(echo ${cipher[$i-1]}%${#array[@]} | bc)
num=$(echo ${cipher[$i-1]}/${#array[@]} | bc)
cipher[$i-1]=$mod
cipher[$i]=$((${cipher[$i]}+$num))
letter=${cipher[$i-1]}
out=${array[$letter]}$out
done
echo $out
}
decode() {
if [ "$4" != "" ]
then
array=($4)
else
array=(- 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)
fi
plain=(0)
cipher=$1
if [ "$3" == "-string" ] || [[ "$2" =~ [^0-9] ]]
then
key=0
for i in $(seq ${#2})
do
index=$(index ${2:i-1:1})
if [ "${index[@]}" != "" ]
then
key=$(echo "$key+${index[0]}*${#array[@]}^($i-1)" | bc)
fi
done
else
key=$2
fi
if [ "$3" == "-integer" ] && [[ "$2" =~ [^0-9] ]]
then
key=0
fi
num=0
out=""
for i in $(seq ${#cipher})
do
if [ "${cipher:$i-1:1}" == " " ]
then
index=0
else
index=$(index ${cipher:$i-1:1})
fi
if [ "${index[@]}" == "" ]
then
plain+=(0)
else
plain+=(${index[0]})
fi
index=$(($num*${#array[@]}+${plain[$i]}))
num=$(($index%$key))
index=$(($index-$num))
index=$(($index/$key))
if [ $index -eq 0 ]
then
out+=" "
else
out+=${array[$index]}
fi
done
if [ "${out:0:1}" == " " ]
then
echo ${out:1}
else
echo $out
fi
}