#!/usr/bin/env bash

# Set up environment
source ~/bin/philomena-env

read oldrev newrev ref
echo "Updating $oldrev -> $newrev ($ref)"

# Clear variable set to '.' so git commands don't complain
unset GIT_DIR

cd ~/philomena

die() {
    echo "$*" 1>&2
    exit 1
}

if git diff --name-only $oldrev $newrev | grep "^mix.exs"; then
  echo "Fetching deps"
  mix deps.get || die "mix failed to update"
fi

# Run migrations
if git diff --name-only $oldrev $newrev | grep "^priv/repo/migrations"; then
  echo "Running database migrations"
  mix ecto.migrate || die "ecto.migrate failed"
fi

# Compile assets
if git diff --name-only $oldrev $newrev | grep "^assets/"; then
  echo "Compiling assets"
  npm install --prefix ./assets || die "assets install failed"
  npm run deploy --prefix ./assets
  mix phx.digest || die "assets compile failed"
fi

# TODO: fix this when I can figure out how to avoid recompiling
# the entire project when the version changes
#
# # Generate release name to always be the current timestamp so that
# # it will be considered an upgrade
# export PHILOMENA_VERSION="0.1.$(date +%s)"

echo "Building release"
mix distillery.release --quiet || die "failed to generate release"

# Find which instance is already started, if either
lsof -i :4000
BLUE_STARTED=$?

lsof -i :4001
GREEN_STARTED=$?

if [[ $BLUE_STARTED == 1 && $GREEN_STARTED == 1 ]]; then
  die "both blue and green instances are running; is another deploy in progress?"
fi

if [[ $BLUE_STARTED == 0 && $GREEN_STARTED == 0 ]]; then
  echo "app not started, starting it now"
  NODENAME=philomena_0 PORT=4000 MNESIA_DIR=/home/derpibooru/philomena/_build/prod/rel/philomena/Mnesia.philomena_0@127.0.0.1 _build/prod/rel/philomena/bin/philomena start
fi

if [[ $BLUE_STARTED == 1 && $GREEN_STARTED == 0 ]]; then
  echo "rolling blue (4000) over to green (4001)"
  BLUE_PID=$(lsof -Fp -i :4000 | head -n1 | sed 's/^p//')
  NODENAME=philomena_1 PORT=4001 MNESIA_DIR=/home/derpibooru/philomena/_build/prod/rel/philomena/Mnesia.philomena_1@127.0.0.1 _build/prod/rel/philomena/bin/philomena start
  sleep 20
  kill -TERM $BLUE_PID
fi

if [[ $BLUE_STARTED == 0 && $GREEN_STARTED == 1 ]]; then
  echo "rolling green (4001) over to blue (4000)"
  GREEN_PID=$(lsof -Fp -i :4001 | head -n1 | sed 's/^p//')
  NODENAME=philomena_0 PORT=4000 MNESIA_DIR=/home/derpibooru/philomena/_build/prod/rel/philomena/Mnesia.philomena_0@127.0.0.1 _build/prod/rel/philomena/bin/philomena start
  sleep 20
  kill -TERM $GREEN_PID
fi