#!/usr/bin/env ruby

require "sinatra/base"
require "dotenv"
require "slim"

module RS
  APP_ENV = ENV.fetch("REMOTE_SYSTEMCTL_ENV") { "development" }
  LOADED_ENV = Dotenv.load(".env.#{APP_ENV}.local", ".env.local", ".env")
  PASSWORDS = LOADED_ENV.filter { |k, _| k =~ /^PASSWORD_/ }.to_h
  SERVICE_NAMES = PASSWORDS.map { |k, _| k.gsub(/^PASSWORD_/, '') }

  class Service
    attr_reader :name, :state

    def initialize(name:)
      @name = name
      @state = "default"
    end

    def password = PASSWORDS["PASSWORD_#{@name}"]
    def start! = act! :start
    def stop! = act! :stop

    private def act!(action)
      `systemctl --user #{action} #{@name}`
      @state = action
    end
  end

  class ServiceIndex
    def initialize(service_list)
      @index = service_list.map { [_1, Service.new(name: _1)] }.to_h
    end

    def [](service_name) = @index[service_name]
    def each(&block) = @index.values.each(&block)
  end

  SERVICES = ServiceIndex.new(SERVICE_NAMES)

  class App < Sinatra::Base
    get "/" do
      slim :index, locals: { services: SERVICES }
    end

    post "/:service/:action" do
      service = SERVICES[params["service"]]
      if !service
        status_code 404
        return "Service not found"
      end

      if params["password"] != service.password
        status_code 403
        return "Invalid password"
      end

      case params["action"]
      when "start"
        service.start!
      when "stop"
        service.stop!
      end
      redirect "/"
    end

    set :bind, ENV["REMOTE_SYSTEMCTL_BIND"] || "127.0.0.1"
    set :port, ENV["REMOTE_SYSTEMCTL_PORT"] || "10001"

    set :environment, APP_ENV
    ENV["RACK_ENV"] = APP_ENV

    run! if app_file == $PROGRAM_NAME
  end
end