msynk/_msynk.compdef.zsh

#compdef msynk
# https://zsh.sourceforge.io/Doc/Release/Completion-System.html#Completion-Functions
_config-file()
{
    # list all files in $CONFIG_DIR
    [[ -z $XDG_CONFIG_HOME ]] && XDG_CONFIG_HOME=~/.config
    opts=($(ls $XDG_CONFIG_HOME/msynk))
    # -s separator, descritions options
    _values -s , 'config files' $opts 
}
_msynk()
{
    # each argument is
    # n:message:action
    # option[description]:message:action
    # *option offer multiple times
    _arguments \
        {--help,-h}'[We all need it at times...]' \
        {--settings,-s}'[Show current settings.]' \
        {--config,-c}'[Use sender, receiver, paths from config file]':config:_config-file \
        '--show-config[Print variables defined by a config file.]':config:_config-file \
        {--sender,-s}'[Sender directory, with trailing "/".]':directory:_directories \
        {--receiver,-r}'[Receiver directory, with trailing "/".]':directory:_directories \
        '--reverse[Swap receiver and sender.]' \
        {--relative,-R}'[User relative path names.]' \
        '--encrypt[Encrypt files before syncing.]' \
        '--decrypt[Decrypt files before syncing.]' \
        '--check-date[Only process files that have been modified since the program was last run. Needs -c and (--encrypt/--decrypt).]' \
        '*--mkrypt-flag[Additional argument for mkrypt.]':mkrypt-flag:_mkrypt \
        {--delete,-d}'[Delete files that exist on receiver, but not on sender. Does not work with --encrypt/--decrypt.]' \
        '--skip-dryrun[Delete without asking first.]' \
        '*--rsync-flag[Additional argument for rsync.]':rsync-flag:_rsync \
        {--verbose,-v}'[Increase verbosity.]' \
        '--silent[Decrease verbosity.]' \
        '--debug[Maximum verbosity.]' \
        '--exclude[Interpret positional arguments as blacklist]' \
        '*:file or directory:_files'
}
_msynk "$@"