Add options with default value on shell script

I want to add some options to my custom shell script. I can show it to you since it is not top secret content :-P

In my experience, there are two option types, set and unset options: set options are typically double-hyphenized, of type --key=value, but can also appear as ordered tuple -k value. Unset options are either short -k or long --key.

From a general perspective, we want to define options, such that they have default configurations and short and long variants. I tried thinking about it, but my current inexperience only allows me to use already defined commands.

There are some special tags, like --help/-h and --version/-v, but I think we have much work already. My attempt so far is below:

UNSET_OPTIONS_SHORT=(
    "-ut1"
    "-ut2"
)

UNSET_OPTIONS_LONG=(
    "--unset_tag_1"
    "--unset_tag_2"
)

UNSET_OPTIONS_DEFAULT=(
    "true"
    "false"
)

SET_OPTIONS_SHORT=(
    "--st1"
    "--st2"
)

SET_OPTIONS_LONG=(
    "--set_tag_1"
    "--set_tag_2"
)

SET_OPTIONS_DEFAULT=(
    "42"
    "mango"
)

SET_OPTIONS_DELIMITER="="

ARGS=( "${@}" )
for arg in ${ARGS[@]}; do
    # parse and identify arguments into between options and inputs
    # It must early-fail in case it cannot parse options, 
    # either short or long formats
done