#! /bin/bash
set -e

: ${APP_PATH:="/app"}
: ${APP_TEMP_PATH:="$APP_PATH/tmp"}
: ${APP_SETUP_LOCK:="$APP_TEMP_PATH/setup.lock"}
: ${APP_SETUP_WAIT:="5"}
: ${HOST_DOMAIN:="host.docker.internal"}

# 1: Define the functions lock and unlock our app containers setup
# processes:
function lock_setup { mkdir -p $APP_TEMP_PATH && touch $APP_SETUP_LOCK; }
function unlock_setup { rm -rf $APP_SETUP_LOCK; }
function wait_setup { echo "Waiting for app setup to finish..."; sleep $APP_SETUP_WAIT; }
function check_host { ping -q -c1 $HOST_DOMAIN > /dev/null 2>&1; }

# 2: 'Unlock' the setup process if the script exits prematurely:
trap unlock_setup HUP INT QUIT KILL TERM EXIT

# 3: Wait for postgres to come up
echo "DB is not ready, sleeping..."
echo "DB is ready, starting Rails."

# 4: Specify a default command, in case it wasn't issued:
if [ -z "$1" ]; then set -- bundle exec rails server -p 3000 -b 0.0.0.0 "$@"; fi

# 5: Run the checks only if the app code is going to be executed:
if [[ "$3" = "rails" ]]
then
  # Clean up any orphaned lock file
  unlock_setup
  # 6: Wait until the setup 'lock' file no longer exists:
  while [ -f $APP_SETUP_LOCK ]; do wait_setup; done

  # 6: 'Lock' the setup process, to prevent a race condition when the
  # project's app containers will try to install gems and setup the
  # database concurrently:
  lock_setup
  # 8: Check if dependencies need to be installed and install them
  bundle check || bundle install

  yarn install
  # 9: Setup the database if it doesn't
  if ! rake db:version
  then
    rake db:setup
  fi

  # check if the docker host is running on mac or windows
  if ! check_host; then
    HOST_IP=$(ip route | awk 'NR==1 {print $3}')
    echo "$HOST_IP $HOST_DOMAIN" | sudo tee -a /etc/hosts > /dev/null
  fi

  # 10: 'Unlock' the setup process:
  unlock_setup

  # 11: If the command to execute is 'rails server', then we must remove any
  # pid file present. Suddenly killing and removing app containers might leave
  # this file, and prevent rails from starting-up if present:
  if [[ "$4" = "s" || "$4" = "server" ]]; then rm -rf /app/tmp/pids/server.pid; fi
fi

# 10: Execute the given or default command:
exec "$@"