#!/bin/bash
# Pronounce a word using English audio from dictionary.cambridge.org
#
#  Copyright (C) 2019 Mike Gerwitz
#
#  This program is free software: you can redistribute it and/or modify
#  it under the terms of the GNU General Public License as published by
#  the Free Software Foundation, either version 3 of the License, or
#  (at your option) any later version.
#
#  This program is distributed in the hope that it will be useful,
#  but WITHOUT ANY WARRANTY; without even the implied warranty of
#  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
#  GNU General Public License for more details.
#
#  You should have received a copy of the GNU General Public License
#  along with this program.  If not, see <http://www.gnu.org/licenses/>.
#
# This script requires wget for scraping and mpv for playback.  Please
# consider your privacy---if you do not want to leak the words you are
# looking up, prefix this command with `torify' to proxy through Tor.
#
# A suggestd improvement to this script to anyone who may want to do so:
# derive region and language from $LANG environment variables.
##

which mpv &>/dev/null || {
  echo 'missing mpv' >&2
  exit 1
}

declare -r name=$( basename "$0" )
declare -r www=${PRONOUNCE_WWW:-https://dictionary.cambridge.org/}
declare -r region=${PRONOUNCE_REGION:-us}
declare -r lang=${PRONOUNCE_LANG:-english}


usage()
{
  cat <<EOU
Usage: $name word
Pronounce WORD using audio from an online dictionary
Ex: $name night

PRIVACY WARNING: This connects to PRONOUNCE_WWW (current value:
$www).
Consider prefixing this command with \`torify' to proxy through Tor.

You may also set PRONOUNCE_REGION (current value \`$region') and
PRONOUNCE_LANG (current value \`$lang').

Copyright (C) 2019 Mike Gerwitz
This program comes with ABSOLUTELY NO WARRANTY.
This is free software, and you are welcome to redistribute it
under certain conditions; see the GNU GPLv3+ for details at
<https://www.gnu.org/licenses/>.
EOU

  exit 64  # EX_USAGE
}


main()
{
  test $# -gt 0 || usage

  local -r word=$1

  local -r ogg_url=$(
    wget -O- "$www/$region/pronunciation/$lang/$word" \
      | grep -o 'data-src-ogg="[^"]\+"' \
      | grep "$region"_pron_ogg \
      | head -n1 \
      | cut -d\" -f2
  )

  test -n "$ogg_url" || {
    echo "US OGG not found for \`$word'" >&2
    exit 1
  }

  mpv -vo null "$www/$ogg_url"
}

main "$@"