#!/bin/sh
#
#  Copyright 2017 Amazon.com, Inc. or its affiliates. All Rights Reserved.
#
#  Licensed under the Apache License, Version 2.0 (the "License").
#  You may not use this file except in compliance with the License.
#  A copy of the License is located at
#
#      http://aws.amazon.com/apache2.0/
#
#  or in the "license" file accompanying this file. This file is distributed
#  on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either
#  express or implied. See the License for the specific language governing
#  permissions and limitations under the License.

while read local_ref local_sha remote_ref remote_sha
do
  branch=$(git rev-parse --symbolic --abbrev-ref $remote_ref)
  if [ "release" == "$branch" ]; then
    # Ensure public github is set to external remote
    if [ $(git remote | grep external | wc -l) == 0 ]; then
      git remote add external https://github.com/aws/aws-ops-wheel.git
    fi
    # Check for release being in sync with most recent version of github repo
    if [ $(git diff origin/release external/master -- . ':!hooks' | wc -l) -gt 0 ]; then
      echo "release does not have the latest changes to the external repository."
      echo "Please pull those changes in before trying to push anything else to this branch."
      exit 1
    fi
    # Ensure a single commit is being pushed at a time
    if [ $(git log --pretty=oneline @{u}.. | wc -l) -gt 1 ]; then
      echo "You are trying to push multiple commits:"
      git log --pretty=oneline @{u}..
      echo "Please rebase and squash commits to continue."
      exit 1
    fi
  fi
done