#!/bin/bash

# This script comes with ABSOLUTELY NO WARRANTY, use at own risk
# Copyright (C) 2021 Osiris Alejandro Gomez <osiux@osiux.com>
#
# 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
# 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/>.

[[ -z "$1" ]] && exit 1
[[ -e "$1" ]] || exit 1

FILE="$1"
TMP1="$(mktemp)"
TMP2="$(mktemp)"
GIT_ORIGIN="$(git remote get-url origin | tr : / | sed 's/git@//g')"
GIT_URL="https://$GIT_ORIGIN/-/commit"

printf "\n** ChangeLog\n\n" > "$TMP1"

git log --no-merges --format="  - [[$GIT_URL/%H][=%ci=]] %s" "$FILE" \
  | grep -v 'ChangeLog:' \
  | sed 's/ -0300//g'    \
  | sed 's/ +0000//g'    \
  | cut -d: -f1,2,4-     >> "$TMP1"

N="$(grep -En '^\*\* ChangeLog$' "$FILE" | cut -d: -f1 | head -1)"

if [[ "$N" -gt 0 ]]
then
  LINE=$((N-1))
  head -n "$LINE" "$FILE" >  "$TMP2"
  cat "$TMP1"             >> "$TMP2" & mv -vf "$TMP2" "$FILE"
else
  cat "$TMP1"             >> "$FILE"
fi