namespace :deploy do
  DEVELOPMENT_APPS = ['example-development']
  STAGING_APPS     = ['example-staging']
  PRODUCTION_APPS  = ['example', 'example2', 'example-demo']
  REMOTE           = ENV['REMOTE_HOST'] || 'git@heroku.com'

  def shell_cmd(cmd)
    begin
      sh "#{cmd}"
    rescue
      puts 'Command failed'.yellow
      exit 0
    end
  end

  def heroku_cmd(cmd)
    begin
      Bundler.with_clean_env do
        sh "heroku #{cmd}"
      end
    rescue
      puts 'Command failed'.yellow
      exit 1
    end
  end

  def choose_app(apps)
    return apps.first if apps.size == 1
    puts 'There are many apps for this environment.'.cyan
    puts 'Please, choose one:'.cyan
    puts apps.map { |a| " - #{a}".green }
    print 'Selected app: '.cyan
    app = STDIN.gets.strip
    unless apps.include?(app)
      puts 'Invalid app selected.'.red
      exit 0
    end
    app
  end

  desc 'Deploy to heroku development app'
  task :development => [:set_development_app, :check, :off, :push, :migrate, :restart, :on]

  desc 'Deploy to heroku staging app'
  task :staging => [:set_staging_app, :check, :off, :promote, :migrate, :restart, :on]

  desc 'Deploy to heroku production app'
  task :production => [:set_production_app, :check, :off, :promote, :migrate, :restart, :on]

  task :set_development_app do
    APP    = choose_app(DEVELOPMENT_APPS)
    DEPLOY = [APP]
    print 'Deploy to development will be done through git push to the following app: '.yellow
    puts APP.cyan
  end

  task :set_staging_app do
    puts 'Deploy to staging is done with heroku pipelines:promote from development app.'.cyan
    PROMOTE = choose_app(DEVELOPMENT_APPS)
    DEPLOY  = STAGING_APPS

    print 'The app '.yellow
    print PROMOTE.green
    print ' will be promoted to the following apps: '.yellow
    puts DEPLOY.to_sentence.green
  end

  task :set_production_app do
    puts 'Deploy to production is done with heroku pipelines:promote from staging app.'.cyan
    PROMOTE = choose_app(STAGING_APPS)
    DEPLOY  = PRODUCTION_APPS

    print 'The app '.yellow
    print PROMOTE.green
    print ' will be promoted to the following apps: '.yellow
    puts DEPLOY.to_sentence.green
  end

  task :check do
    print 'Are you sure you want to proceed (y/n)? '.yellow
    input = STDIN.gets.strip
    if input == 'y'
      puts 'Lets go'.green
    else
      puts [
        'Sorry for the confusion.',
        'More luck next time.',
        'That was close.'
      ].sample.green
      exit 0
    end
  end

  task :promote do
    puts 'Promoting app to its downstream app(s)'
    heroku_cmd "pipelines:promote --app #{PROMOTE}"
  end

  task :push do
    puts 'Pushing to heroku git remote'
    shell_cmd "git push #{REMOTE}:#{APP}.git master"
  end

  task :migrate do
    puts 'Running database migrations...'
    DEPLOY.each do |app|
      heroku_cmd "run rake db:migrate --app #{app}"
    end
  end

  task :off do
    puts 'Putting apps in maintenance mode...'
    DEPLOY.each do |app|
      heroku_cmd "maintenance:on --app #{app}"
    end
  end

  task :on do
    puts 'Taking apps out of maintenance mode...'
    DEPLOY.each do |app|
      heroku_cmd "maintenance:off --app #{app}"
    end
  end

  task :restart do
    puts 'Restarting app servers ...'
    DEPLOY.each do |app|
      heroku_cmd "restart --app #{app}"
    end
  end
end