#!/bin/sh
#
# check-patch [-v] <patch>
#
# Check a patch for updates in its parent

set -e

if [ "$1" = "-v" ]; then
    VERBOSE="echo"
    shift
else
    VERBOSE=":"
fi

if [ "$#" -ne 1 ]; then
  echo "Usage: check-patch [-v] <patch>"
  exit 1
fi

PATCHDIR="$(dirname "$1")"
PATCHNAME="$(basename "$1")"

PARENTNAME="$(grep "^## Parent-Name:" $PATCHDIR/$PATCHNAME | cut -d: -f2- | xargs)"
PARENTVERSION="$(grep "^## Parent-Version:" $PATCHDIR/$PATCHNAME | cut -d: -f2- | xargs)"
PARENTMD5="$(grep "^## Parent-MD5:" $PATCHDIR/$PATCHNAME | cut -d: -f2- | xargs)"

NOWMD5="$(md5sum "$PATCHDIR/$PARENTNAME" | cut -b-32)"

if ! [ "$PARENTMD5" = "$NOWMD5" ]; then
  echo "$PATCHDIR/$PATCHNAME needs updating"
  echo "  Parent-Name:    $PARENTNAME"
  echo "  Parent-Version: $PARENTVERSION"
  echo "  Parent-MD5:     $PARENTMD5"
  echo "  MD5 is now:     $NOWMD5"
  exit 1
fi

$VERBOSE "$PATCHDIR/$PATCHNAME is current"