#!/bin/bash

name="mktar"
version="1.4"
read -r -d '' help_message <<-EOF
	Archive utility
	Usage: mktar -n OUTFILE [OPTIONS] INFILES
	Options:
	 --checksum=ALGO             create checksum with [none|sha1|sha256]
	 -h, --help                  print this message
	 -n FILE, --name FILE        name of archive
	 -p PASS, --passphrase PASS  passphrase for encryption
	 -q, --quiet                 suppress error messages and prompts
	 -v, --verbose               show additional messages
	 -V, --version               print version number and exit
EOF

source /usr/local/lib/mylib.bash
source /usr/local/lib/archive.bash

archive_fn=""
checksum=-1
positional=()
quiet=0
verbose=0
while [[ $# -gt 0 ]]; do
  case $1 in

  --checksum=no|--checksum=none|--checksum=0)
    debug_msg "Setting checksum option to 0 (=none) (was ${checksum})"
    checksum=0
    shift
    ;;

  --checksum=sha1|--checksum=1)
    debug_msg "Setting checksum option to 1 (=sha1) (was ${checksum})"
    checksum=1
    shift
    ;;

  --checksum=sha256|--checksum=2)
    debug_msg "Setting checksum option to 2 (=sha256) (was ${checksum})"
    checksum=2
    shift
    ;;

  --checksum=*)
    attempted_checksum="$(/usr/bin/printf "%s\n" "$1" | sed -e 's/^.*=//' )"
    error_msg "Unknown checksum '${attempted_checksum}'"
    ;;

  -h|--help)
    help_msg
    shift
    ;;

  -n|--name)
    debug_msg "Setting output filename to ${2} (was ${archive_fn})"
    archive_fn="$2"
    shift; shift
    ;;

  -p|--passphrase)
    debug_msg "Setting passphrase to ${2} (was ${passphrase})"
    passphrase="--passphrase $2"
    shift; shift
    ;;

  -q|--quiet)
    debug_msg "Setting quiet option to 1 (was ${quiet})"
    quiet=1
    shift
    ;;

  -v|--verbose)
    debug_msg "Setting verbose option to 1 (was ${verbose})"
    verbose=1
    shift
    ;;

  -V|--version)
    version_msg
    ;;

  *)
    debug_msg "Argument '${1}' added to positional array"
    positional+=("$1")
    shift
    ;;
  esac
done

# error if no archive file given
if [[ -z "$archive_fn" ]]; then
  error_msg "no archive file given"
  usage_msg
fi

# determine archive action
archive_action="$(archive_extension "$archive_fn" | tee >(>&2 /usr/bin/head -n -1) | /usr/bin/tail -n 1)"

# determine checksum action and filename
if [[ "$checksum" -eq 1 ]]; then
  checksum_action="sha1"
elif [[ "$checksum" -eq 2 ]]; then
  checksum_action="sha256"
fi
checksum_fn="$(fn_basename "$archive_fn").${checksum_action}"

# check checksum files
if [[ "$checksum" -ge 1 ]]; then
  if contains "$checksum_fn" "${positional[@]}"; then
    error_msg "checksum '${checksum_fn}' cannot be an input file"
  elif ! prompt_overwrite "checksum_fn"; then
    error_msg "checksum '${checksum_fn}' cannot be overwritten"
  fi
fi

# check passphrase
if [[ "$encrypt" -ge 1 && -z "$passphrase" ]]; then
  passphrase=
fi

if ! archive --archive=$archive_action --name "$archive_fn" $passphrase "${positional[@]}"; then
  exit 1
fi

code=0
if [[ "$checksum" -ge 1 ]]; then
  case "$checksum_action" in
  sha1)
    if ! /usr/bin/sha1sum "$archive_fn" | /usr/bin/awk '{print $1}' > "$checksum_fn"; then
      code=1
    fi
    ;;

  sha256)
    if ! /usr/bin/sha256sum "$archive_fn" | /usr/bin/awk '{print $1}' > "$checksum_fn"; then
      code=1
    fi
    ;;
  esac
fi

exit "$code"