#!/usr/bin/env bash

# Downloads a public stemcell for CPI into /var/vcap/store/stemcells/
#
# Required:
# * $MICRO_BOSH_STEMCELL_NAME - public stemcell name to be downloaded
#                             - if 'custom' the create stemcell from BOSH source
#
# Optional:
# * $PROVIDER - required for 'custom' $MICRO_BOSH_STEMCELL_NAME; e.g. aws, openstack
# * $BOSH_RELEASE_REPO - defaults to https://github.com/cloudfoundry/bosh-release.git

set -e # exit immediately if a simple command exits with a non-zero status
set -u # report the usage of uninitialized variables

if [[ $EUID -ne 0 ]]; then
  echo "ERROR: This script must be run as root" 1>&2
  exit 1
fi

if [[ "${MICRO_BOSH_STEMCELL_NAME}X" == "X" ]]; then
  echo 'INTERNAL ERROR: Missing $MICRO_BOSH_STEMCELL_NAME environment variable'
  exit 1
fi

if [[ "${MICRO_BOSH_STEMCELL_NAME}" == "custom" ]]; then

  BOSH_RELEASE_REPO=${BOSH_RELEASE_REPO:-'https://github.com/cloudfoundry/bosh-release.git'}
  BOSH_RELEASE_DIRNAME=${BOSH_RELEASE_DIRNAME:-'bosh-release'}
  BOSH_RELEASE_DIR=/var/vcap/store/releases/$BOSH_RELEASE_DIRNAME

  echo "Creating custom stemcell..."

  if [[ -d /var/tmp/bosh/ ]]; then
    echo "But first, cleaning out previous stemcell temporary files..."
    rm -rf /var/tmp/bosh
  fi


  cd $(dirname $BOSH_RELEASE_DIR)
  if [[ -d $BOSH_RELEASE_DIRNAME ]]; then
    echo "Updating BOSH's own bosh-release for custom stemcell"
    cd $BOSH_RELEASE_DIRNAME
    git pull origin master
  else
    echo "Fetching BOSH's own bosh-release for custom stemcell"
    git clone $BOSH_RELEASE_REPO
    cd $BOSH_RELEASE_DIRNAME
  fi

  echo -e "Host github.com\n\tStrictHostKeyChecking no\n" >> ~/.ssh/config

  echo "Rewriting all git:// & git@ to https:// to allow access if port 22 is blocked..."
  # Snippet written by Mike Reeves <swampfoxmr@gmail.com> on bosh-users mailing list
  # Date 2012-12-06
  grep -rI "git[@:/]\{0,3\}github.com" * .gitmodules | awk 'BEGIN {FS=":"} { print($1) }' | while read file
  do
    echo "changing - $file"
    sed -i 's/git\:\/\/github.com/https:\/\/github.com/g' $file
    sed -i 's/git@github.com:/https:\/\/github.com\//g' $file
  done

  echo "Updating source submodules..."
  git submodule update --init

  echo "Within submodules, rewriting all git:// & git@ to https:// to allow access if port 22 is blocked..."
  # Snippet written by Mike Reeves <swampfoxmr@gmail.com> on bosh-users mailing list
  # Date 2012-12-06
  grep -rI "git[@:/]\{0,3\}github.com" * .gitmodules | awk 'BEGIN {FS=":"} { print($1) }' | while read file
  do
    echo "changing - $file"
    sed -i 's/git\:\/\/github.com/https:\/\/github.com/g' $file
    sed -i 's/git@github.com:/https:\/\/github.com\//g' $file
  done

  echo "Creating bosh release (fetching any new blobs)..."
  bosh -n create release --force --with-tarball

  # dev_releases/index.yml contains the dev_releases
  # and its last line contains the latest dev_release name
  # For example:
  # --- 
  # builds: 
  #   4800ad1226e2b673595a8646e8e11bc968ab6ab6: 
  #     version: 119.1-dev
  #   7e0318d711daf0a5fa2e65c0257cd3b6af2ec4e5: 
  #     version: 119.2-dev
  #
  # So to get the latest dev_release name, grab the last line's 2nd token
  # For example, above this would be "119.2-dev"
  RELEASE_NAME="bosh-release"
  LATEST_DEV_RELEASE_NAME=$(tail -n 1 dev_releases/index.yml | awk '{print $2}')
  LATEST_BOSH_RELEASE_PATH=$BOSH_RELEASE_DIR/dev_releases/$RELEASE_NAME-$LATEST_DEV_RELEASE_NAME.tgz
  MICRO_BOSH_MANIFEST_PATH=$BOSH_RELEASE_DIR/micro/$PROVIDER.yml

  BOSH_DIR=/var/vcap/store/repos/bosh
  cd $(dirname $BOSH_DIR)
  if [[ -d bosh ]]; then
    echo "Updating bosh source for agent/stemcell scripts"
    cd bosh
    git pull origin master
  else
    echo "Cloning bosh source for agent/stemcell scripts"
    git clone https://github.com/cloudfoundry/bosh.git
    cd bosh
  fi

  cd $BOSH_DIR
  echo "Creating custom stemcell..."
  bundle install --without test development
  bundle exec rake stemcell:micro[$PROVIDER,$MICRO_BOSH_MANIFEST_PATH,$LATEST_BOSH_RELEASE_PATH]

  echo "Copying to stemcells folder..."
  MICRO_BOSH_STEMCELL_PATH=$(ls -t /var/tmp/bosh/agent-*/work/work/*.tgz | sort | tail -n 1)
  mv $MICRO_BOSH_STEMCELL_PATH /var/vcap/store/stemcells
  MICRO_BOSH_STEMCELL_NAME=$(basename $MICRO_BOSH_STEMCELL_PATH)

  echo "Cleaning up..."
  rm $(dirname $LATEST_BOSH_RELEASE_PATH)/*.tgz

elif [[ -f /var/vcap/store/stemcells/$MICRO_BOSH_STEMCELL_NAME ]]; then
  echo "Stemcell $(pwd)/$MICRO_BOSH_STEMCELL_NAME already exists."

else
  cd /var/vcap/store/stemcells
  echo "Downloading public stemcell $MICRO_BOSH_STEMCELL_NAME"
  # set $COLUMNS manually else progressbar runs `tput cols`.to_i which causes grief
  COLUMNS=80 bosh -n download public stemcell $MICRO_BOSH_STEMCELL_NAME
fi

# print name of stemcell created/downloaded to be stored back in settings
echo $MICRO_BOSH_STEMCELL_NAME