Rewrite a script so it takes option arguments to control its behaviour - linux

Question

I created a script and it moves files with different extensions to their specified directories.
If the directory is not there, it creates another one (where the files will go), and it creates another directory where the remaining files with different extensions will go.
My first problem is that I want when I put -d and full path on the terminal it should move only media files, -l and full path to move all text files, then -x to change the extension to uppercase, then -u to lowercase.
Can somebody modify it for me and show me how to overcome this problem?
#!/bin/bash
From="/home/elg19/lone/doc"
To="/home/elg19/mu"
WA="/home/elg19/du"
MA="/home/elg19/dq"
WQ="/home/elg19/d2"
# this function checks if the directory exits and creates one if it does not then moves all doc files
function mama(){
if [[ ! -d "$WA" ]]; then
mkdir -p "$WA"
fi
cd "$From"
for i in pdf txt doc; do
find . -type f -name "*.${i}" -exec mv "{}" "$WA" \;
done
}
# this function checks if the directory exits and creates one if it does not then moves all media files
function so(){
if [[ ! -d "$To" ]]; then
mkdir -p "$To"
fi
cd "$From"
for i in mp3 mp4 swf; do
find . -type f -name "*.${i}" -exec mv "{}" "$To" \;
done
}
# this function checks if the directory exits and creates one if it does not then moves all image files
function soa(){
if [[ ! -d "$MA" ]]; then
mkdir -p "$MA"
fi
cd "$From"
for i in jpg gif png; do
find . -type f -name "*.${i}" -exec mv "{}" "$MA" \;
done
}
# this function checks if the directory exits and creates one if it does not then moves all the remaining files
function soaq(){
if [[ ! -d "$WQ" ]]; then
mkdir -p "$WQ"
fi
cd "$From"
for i in *; do
find . -type f -name "*.${i}" -exec mv "{}" "$WQ" \;
done
}
mama
so
soa
soaq

Answer 1

I don't know if the options suggested are mnemonic in your native language, but they are counter-mnemonic in English. I would suggest something more like:
-m path Move media files
-t path Move text files
-u Change extensions to upper-case
-l Change extensions to lower-case
The command to use for regular argument parsing like this is getopts (plural - many systems also have a command getopt, singular, which has different characteristics altogether).
The referenced page gives an example of how to use it:
The following example script parses and displays its arguments:
aflag=
bflag=
while getopts ab: name
do
case $name in
a) aflag=1;;
b) bflag=1
bval="$OPTARG";;
?) printf "Usage: %s: [-a] [-b value] args\n" $0
exit 2;;
esac
done
if [ ! -z "$aflag" ]; then
printf "Option -a specified\n"
fi
if [ ! -z "$bflag" ]; then
printf 'Option -b "%s" specified\n' "$bval"
fi
shift $(($OPTIND - 1))
printf "Remaining arguments are: %s\n" "$*"
The option -a doesn't take an argument; the option -b requires an argument.