#!/bin/sh

# contributors: Generate MAINTAINERS content from git commits
#
# Author: Steven Enten <steven@enten.fr>
# License : MIT
# Requirements: dirname cat echo eval grep read readlink shift tail
# Site: https//github.com/enten/losh

set -u

#
# consts
#
CMDDESC="Generate MAINTAINERS content from git commits"
FILE=

#
# vars
#
buffer=
tmp=

#
# initialize vars
#
init() {
  tmp=$(dirname $(readlink -f $(echo $0)))

  while [ ! -f "$tmp/MAINTAINERS" ]; do
    tmp=$(dirname $tmp)
    [ "$tmp" = "/" ] && break
  done

  [ ! -f "$tmp/MAINTAINERS" ] && echo "MAINTAINERS was not found" && exit 1

  FILE="$tmp/MAINTAINERS"

  return 0
}

#
# Add new maintainer into MAINTAINERS
#
add_maintainer() {
  echo $buffer | grep -q "$1"
  if [ $? -ne 0 ]; then
     [ -z "$buffer" ] && buffer="$1" || buffer="$buffer $1"
     tmp=$(echo "git log --author='$1'")
     echo "$1 (since $(eval $tmp --format='%aD' | tail -n 1), $(eval $tmp --format='%ar' | tail -n 1))" >> $FILE
  fi
}

#
# Generate MAINTAINERS file
#
update_maintainers() {
  echo "# Last update: $(date)" > $FILE
  buffer=
  git log --format='%an <%ae>' > $FILE.tmp
  while read i; do
    add_maintainer "$i"
  done < $FILE.tmp
  rm -f $FILE.tmp
}

#
# Print MAINTAINERS content
#
print_maintainers() {
  cat $FILE
}

#
# One main to rull them all
#
main() {
  init
  update_maintainers
  print_maintainers
}

main