#!/usr/bin/env bash
# ---
# @file_name: pwgen.sh
# @version: 1.0.1
# @description: Generate a passphrase
# @author: Jamie Albert (empty_produce)
# @author_contact: <mailto:empty.produce@flatmail.me>
# @license: GNU Affero General Public License v3.0 (Included in LICENSE)
# Copyright (C) 2025, Jamie Albert
# ---
set -euo pipefail

declare -gr WORD_LIST='/usr/share/dict/japg.list'
declare -gr DEFAULT_DELIM='-'
declare -gi DEFAULT_WORDS=5


# ---
# @return_code: [2] Word-list file not found.
# @return_code: [3] Required tool 'xclip' not found.
# shellcheck disable=1091,1090
# ---
setup() {
	. /usr/local/share/dao/libs/libs_dao.sh
  [[ -f "${WORD_LIST}" ]] || dao::error 2 "Word-list not found: $WORD_LIST"
  command -v xclip >/dev/null || dao::error 3 "xclip not found (install xclip)"
}

# ---
# @arg: $1 - Number of words (optional, defaults to DEFAULT_WORDS).
# @arg: $2 - Delimiter (optional, defaults to DEFAULT_DELIM).
# @return_code: [1] General dao::error (inherits from set -e).
# @return_code: [4] Invalid number of words provided.
# @return_code: [2] Word-list not found (inherited from setup).
# @return_code: [3] xclip not found (inherited from setup).
# ---
main() {
  setup

  declare num_words="${1:-$DEFAULT_WORDS}"
  declare delim="${2:-$DEFAULT_DELIM}"

  [[ "${num_words}" =~ ^[1-9][0-9]*$ ]] || dao::error 4 "num_words must be a positive integer"

  declare -a words
  mapfile -t words < <(shuf -n "$num_words" "$WORD_LIST") || dao::error 1 "Failed to read words from list"

  declare i
  for i in "${!words[@]}"; do
    words[i]="${words[i]^}"
  done

  declare dig_idx=$(( RANDOM % num_words ))
  words[dig_idx]+=$(( RANDOM % 10 ))

  declare pass
  IFS="$delim"
  printf -v pass '%s' "${words[*]}" || dao::error 1 "Failed to construct passphrase"

  printf '%s' "$pass" | xclip -selection clipboard || dao::error 1 "Failed to copy passphrase to clipboard"
  dao::info "Generated password: $pass"
  dao::info "Password copied to clipboard."
}

main "$@"