#!/bin/bash
#
# COMMIT-MSG, hook script to verify commit message
# Copyright (C) 2022-2023 Xavier Delaruelle
#
# 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 2 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/>.

##########################################################################

# redirect output to stderr.
exec 1>&2

# apply SGR code to message if output channel is attached to terminal
sgr() {
   local code=$1
   local msg=$2
   if [ -t 2 ]; then
      echo "\033[${code}m${msg}\033[0m"
   else
      echo "$msg"
   fi
}

echo_warning() {
   echo -e "$(sgr 43 WARNING): $1"
}

echo_error() {
   echo -e "$(sgr 41 ERROR): $1"
}

echo_hint() {
   echo -e "$(sgr 44 HINT): $1"
}

# check misspellings in commit message
command -v hunspell >/dev/null
if [ $? -eq 0 ]; then
   HUNSPELL_OPTS=(-d en_US -p .hunspell.en.dic)
   # use sed to extract commit message from full commit details
   words=$(sed '/^# /Q' "$1" | hunspell "${HUNSPELL_OPTS[@]}" -l)
   # abort if misspelled words found
   if [ -n "$words" ]; then
      befmsg='# commit message was ---------------- >8 -------------'
      aftmsg='# ------------------------ 8< ------------------------'
      echo_error "misspellings found in commit message\n\n$words\n"
      echo -e "$befmsg\n$(sed '/^# /Q' "$1")\n$aftmsg\n"
      echo_hint "correct message or skip checks with '--no-verify' git option"
      exit 1
   fi
else
   echo_warning "hunspell command not found"
fi

exit 0

# vim:set tabstop=3 shiftwidth=3 expandtab autoindent: