#! /bin/bash

set -e
set -o nounset

# Preparation

## Get the new version number from the most recent tag

LATEST_TAG=$(git describe --abbrev=0 --match='v*')
VERSION=${LATEST_TAG#v}
echo Attempt to build distributables for version $VERSION
# NB does not check that this tag is on master

echo
echo == Sanity checks

## Check that the version doesn't already exist by looking at github
## releases
if curl -sSf https://api.github.com/repos/zettio/weave/releases/$LATEST_TAG 2>/dev/null; then
    echo Release $LATEST_TAG already exists on GitHub
    echo https://github.com/zettio/weave/releases/$LATEST_TAG
    exit 1
fi

## Clone the repo at the tag and go there
RELEASE_DIR=releases/$LATEST_TAG
mkdir -p releases
git clone -q -b $LATEST_TAG . $RELEASE_DIR
cd $RELEASE_DIR

## Check that the top changelog entry is this version
latest_changelog=$(grep -o "Release v.*" -m1 ./CHANGELOG.md)
if ! [ `echo "$latest_changelog" | grep -o 'v[^ ]*'` == $LATEST_TAG ]; then
    echo Latest changelog entry $latest_changelog does not match
    echo the latest tag $LATEST_TAG
    exit 1
fi

echo Sanity checks OK for releasing tag $LATEST_TAG

echo
echo == Build and test

## Inject the version numbers and build the distributables
## (library versions?)

sed -i "/var version = / c\var version = \"$VERSION\"" weaver/main.go
make

## Run tests with the distributables, including version check
v=$(./weaver/weaver --version)
if ! [ "$v" == "weaver $VERSION" ]; then
    echo Version of distributable "$v" does not match tag $LATEST_TAG
    exit 1
fi

make tests

echo Build and tests OK

# Publish

## Either leave the distributables in a directory for the dev to
## upload, or upload them automatically?