#!/usr/bin/env bash

function xkcdpassgen {
    local use_upper=true use_number=true use_symbol=true
    local OPTIND opt

    while getopts "UNS" opt; do
        case "$opt" in
            U) use_upper=false ;;
            N) use_number=false ;;
            S) use_symbol=false ;;
        esac
    done
    shift $((OPTIND - 1))

    if [ -z "$1" ]; then
        echo "Usage: xkcdpassgen [-U] [-N] [-S] <pass-entry-name>" >&2
        echo "  -U  omit uppercase letter" >&2
        echo "  -N  omit number" >&2
        echo "  -S  omit symbol" >&2
        return 1
    fi

    local base_pass suffix="" password
    base_pass="$(xkcdpass -n 3 | tr -d ' ')"

    if $use_upper; then
        suffix+="$(echo {A..Z} | tr ' ' '\n' | shuf -n1)"
    fi
    if $use_number; then
        suffix+="$(shuf -i 0-9 -n1)"
    fi
    if $use_symbol; then
        suffix+="$(echo '!@#$%^&*' | fold -w1 | shuf -n1)"
    fi

    password="${base_pass}${suffix}"

    echo "$password" | pass insert -e "$1"
}

xkcdpassgen "$@"