# Mentorenwahl: A fullstack application for assigning mentors to students based on their whishes.
# Copyright (C) 2022  Dominic Grimm
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program.  If not, see <https://www.gnu.org/licenses/>.

require "service"
require "log"
require "retriable"
require "clear"

module Backend
  # Backend runner
  class Runner < Service::Runner
    Log = ::Log.for(self)

    # Service starters
    def starters : Array(Service::Starter)
      [
        Service::SynchronousStarter.new([
          Web::Service.new.as(Service),
          Worker::Service.new.as(Service),
        ] of Service).as(Service::Starter),
      ]
    end

    # Run the backend
    def run : self
      {% if !flag?(:release) %}
        Log.warn { "Backend is running in development mode! Do not use this in production!" }
        pp Backend.config
      {% end %}

      Log.info { "Checking if DB schema is up to date..." }
      Retriable.retry(backoff: false, base_interval: 10.seconds, multiplier: 1.0) do
        ex : Clear::SQL::Error? = nil
        if begin
             Db.schema_up_to_date?
           rescue exc : Clear::SQL::Error
             ex = exc

             false
           end && ex.nil?
          Log.info { "Database schema is up to date." }
        else
          Log.warn { "Database schema is not up to date. Please run `bash scripts/micrate.sh up`." }
          if ex
            raise ex
          else
            raise "Database schema is not up to date" unless Backend.config.db.allow_old_schema
          end
        end
      end

      Log.info { "Starting services..." }

      super
    end
  end
end