#!/bin/sh

if [ -z "${1}" -o "${1}" = '-h' -o "${1}" = '--help' ]
then
    echo "Usage: snapshot-version <new-version>" >&2
    exit 1
fi

if  [ ! -s "${PWD}/application.properties"  -o \
      ! -d "${PWD}/build" ] || \
        ! grep -q -E 'app\.name[[:blank:]]*=[[:blank:]]*mws' \
        "${PWD}/application.properties"
then
    echo "It appears that the present working directory" >&2
    echo "  '${PWD}' doesn't describe the root source" >&2
    echo "  path." >&2
    echo "  This script must be run from the root souce path." >&2
    exit 1
fi

if [ -n "`git status --porcelain`" ]
then
    echo "It appears that the working directory is not clean." >&2
    echo "  cannot continue." >&2
    exit 1
fi

current_version="`build/determine-version`"

echo "This script will cause additional commits to be made."
printf "continue [y/N]? "
read answer
echo ""
if ! echo "${answer}" | grep -i -q '^y'
then
    echo "You have not answered yes."
    echo "Exiting."
    exit 0
fi

set -x
git add application.properties || :
ed application.properties << ED
/app\.version
s@${current_version}@${1}@
wq
ED
git commit -a -m "Snapshot version at '${1}' from '${current_version}'"
git tag -a "${1}" -m "Snapshot version at '${1}' from '${current_version}'"
ed application.properties << ED
/app\.version
s@${1}@${current_version}@
wq
ED
git commit -a -m "Restore version from '${1}' to '${current_version}'"
set +x

echo "Successfully taken snapshot with version '${1}'."
echo "To look at what was done, run:"
echo "  git log -3"
echo "  git tag -l | grep '${1}'"
echo "If you like the changes, run:"
echo "  git pull --rebase"
echo "  git push"
echo "  git push --tag"
echo "If you don't like the changes, run:"
echo "  git reset --hard HEAD^^"
echo "  git tag -d '${1}'"