#!/bin/sh

if git describe --match 'dosemu2*' >/dev/null 2>&1 ; then
  USE_GIT=1
else
  USE_GIT=0
fi

if [ "$USE_GIT" = "1" ]; then
  # need -n 1 for merge commits
  DATE=`git log HEAD^..HEAD -n 1 --format=%cd --date=short`
  REV=`git describe --match dosemu-1.5.0 | cut -d- -f3`
else
  DATE=`date -r VERSION +%F`
  REV=`tail -n 1 VERSION`
fi

if test "$1" = "-r"; then
  shift
  if [ -n "$1" ]; then
    REV=`git rev-list dosemu-1.5.0..$1 --count`
  fi
  echo "$REV"
  exit 0
fi

if test "$1" = "-d"; then
  echo "$DATE"
else
  if [ "$USE_GIT" = "1" ]; then
    DATE=`echo "$DATE" | sed -e 's/-//g'`
    gd=`git describe --tags --match '*2.*' HEAD 2>/dev/null`
    s=`echo $gd | sed -e "s/-\([^-]\+-g\)/-$DATE-\1/"`
    ss=`echo $gd | sed -e "s/-[^-]\+-g.*/\.$DATE/"`
  fi
  v1=`head -n 1 VERSION`
  if test -z "$gd"; then
    s=$v1
    ss=$v1
    v=$v1
  else
    v=`echo $gd | cut -d - -f 1`
  fi
  if test "$1" = "-s"; then
    echo "$v"
    exit 0
  fi
  if test "$1" = "-b"; then
    echo "$ss"
    exit 0
  fi
  if test "$1" = "-u"; then
    r1=`tail -n 1 VERSION`
  fi
  if [ -n "$v" -a "$v" != "$v1" ] || [ -n "$r1" -a "$REV" != "$r1" ]; then
    echo "Update VERSION $v1 -> $v" >&2
    echo $v > VERSION
    echo "$REV" >> VERSION
  fi
  echo $s
fi