#!/usr/bin/env bash
# pw - a mnml password manager

command -v gpg >/dev/null 2>&1 && gpg=gpg
command -v gpg2 >/dev/null 2>&1 && gpg=gpg2

# check if xclip or pbcopy exist
# command -v xclip >/dev/null 2>&1 && copy="xclip -rmlastnl -selection clipboard"
# command -v pbcopy >/dev/null 2>&1 && copy="pbcopy | tr -d '\n'"

# export PW_DIR to your own path
[[ -z "$PW_DIR" ]] && PW_DIR="$HOME/.pw"

init() {
    if [[ ! -e "$PW_DIR" ]]; then
        mkdir -p "$PW_DIR"
        printf "pw: password directory initialized at %s\n" "$PW_DIR"
    else
        printf "PW_DIR is %s\n" "$PW_DIR"
        die "$PW_DIR exists"
    fi
}

add() {
    # $1: path to file
    # $2 [optional]: password text
    [[ -z "$PW_KEY" ]] && die "\$PW_KEY not set"

    if [[ "$#" -eq 2 ]]; then
        pass="$2"
    else
        # uses default length of 25 chars, unless PW_LEN is set
        pass="$(pwgen "${PW_LEN:-25}" 1 -s)"
        printf "pw: generated password for %s\n" "$1"
    fi
    if [[ ! -f "$PW_DIR/$1.gpg" ]]; then
        printf "%s" "$pass" | "$gpg" -aer "$PW_KEY" -o "$PW_DIR/$1.gpg"
        printf "pw: %s/%s.gpg created\n" "$PW_DIR" "$1"
    else
        die "the file $PW_DIR/$1.gpg exists"
    fi
    (
        cd $PW_DIR
        git add .
        git commit -m "$(date)"
        remote="$(git remote show)"
        branch="$(git branch --show-current)"
        git pull -r "$remote" "$branch"
        git push "$remote" "$branch"
    )
}

list() {
    for f in "$PW_DIR"/*.gpg; do
        printf '%s\n' "$(basename "${f%.gpg}")"
    done
}

del() {
    checkf "$PW_DIR/$1.gpg"
    read -rn 1 -p "pw: are you sure you want to delete $1? [y/n]: "
    printf "\n"
    [[ "$REPLY" == [yY] ]] && {
        rm -f "$PW_DIR/$1.gpg"
        printf "pw: deleted %s" "$1"
    }
}

show() {
    checkf "$PW_DIR/$1.gpg"
    "$gpg" --decrypt --quiet --use-agent "$PW_DIR/$1.gpg"
}

# TODO: rework having to checkf twice

copy() {
    checkf "$PW_DIR/$1.gpg"
    if [[ "$OSTYPE" =~ darwin* ]]; then
        show "$1" | head -1 | pbcopy | tr -d '\n'
    else
        show "$1" | head -1 | xclip -rmlastnl -selection clipboard
    fi
    printf "pw: copied %s to clipboard\n" "$1"
}

usage() {
    usage="
pw - mnml password manager

usage: pw [options] [NAME]
All options except -i and -h require a NAME argument.

options:
  -i            Initializes password directory at \$HOME/.pw or at \$PW_DIR, if it exists.
  -a            Add a password.
  -g            Generate a password.
  -s            Print password to STDOUT.
  -l            List out all passwords.
  -c            Copy existing password to clipboard.
  -d            Delete password.
  -h            Display this help message and exit.

Requires PW_KEY to be set. Optionally, set PW_DIR for custom directory location.
Set PW_LEN to an integer of your choice, to override the default password length of 25.
"

    printf "%s" "$usage"
    exit 1
}

checkf() {
    [[ ! -f "$1" ]] &&
        die "$1 does not exist"
}

die() {
    printf "error: %s\n" "$1" >&2
    exit 1
}


main() {
    [[ -z "$1" ]] && {
        usage
    }

    while getopts "ila:g:s:c:d:h" options
    do
        # shellcheck disable=SC2221,SC2222
        case "$options" in
            i) init ;;
            l) list ;;
            g) add "$OPTARG" ;;
            a)
               read -rsp "enter password: " pass
               printf "\n"
               add "$OPTARG" "$pass"
               ;;
            s) show "$OPTARG" ;;
            c) copy "$OPTARG" ;;
            d) del "$OPTARG" ;;
            *|h) usage ;;
        esac
    done

    shift $(( OPTIND -1 ))
}

main "$@"