#!/bin/bash
ARCHIVE="${HOME}/Nextcloud"

comp() {
    find "${ARCHIVE}" -maxdepth $2 -type d -regextype posix-extended -regex "$1"
}

_cda() {
    if [ ! -z "$2" ]; then
        local cur
        COMPREPLY=()
        cur="${COMP_WORDS[COMP_CWORD]}"

        if [ "${#2}" = "1" ]; then
            D1=$(comp "${ARCHIVE}/[0-9]-.*" 1)
            target=$(printf "${D1}" | grep "$2" | xargs basename)
        elif [ "${#2}" = "3" ]; then
            D2=$(comp "${ARCHIVE}/[0-9]+-[^/]+/[0-9]{3}-.*" 2)
            target=$(printf "${D2}" | grep "$2" | xargs basename)
        elif [ "${#2}" = "6" ]; then
            D3=$(comp "${ARCHIVE}/[0-9]+-[^/]+/[0-9]{3}-[^/]+/[0-9]{3}\.[0-9]{2}-.*" 3)
            target=$(printf "${D3}" | grep "$2" | xargs basename)
        elif [ "${#2}" = "9" ]; then
            D4=$(comp "${ARCHIVE}/[0-9]+-[^/]+/[0-9]{3}-[^/]+/[0-9]{3}\.[0-9]{2}-[^/]+/[0-9]{3}\.[0-9]{2}\.[a-zA-Z]+-.*" 4)
            target=$(printf "${D4}" | grep "$2" | xargs basename)
        fi
        echo "$target"
        COMPREPLY=($(compgen -W "${target}" $cur))
    fi
}

complete -F _cda cda