class Admin::AdminController < ApplicationController

  layout 'admin'

  # The admin has two roles: Admin, who gets everything, and Guest (the `user`
  # role), who gets a read-only slice -- the analytics dashboard and the
  # published leaderboard. Listed by controller name.
  GUEST_SECTIONS = %w[analytics leaderboard].freeze

  # The nav sections in the order they appear in the sidebar.
  ADMIN_SECTIONS = %i[analytics leaderboard nodes assets].freeze

  before_action :authenticate_user!
  before_action :only_permitted_section!
  before_action :set_locale_to_default

  helper_method :current_user
  helper_method :user_signed_in?
  helper_method :form_locale, :available_locales
  helper_method :admin?, :permitted_admin_sections

  # DELETE admin/cache/clear
  def clear_cache
    Rails.cache.clear

    respond_to do |format|
      format.turbo_stream { flash.now[:notice] = t(:cache_cleared, scope: 'utils') }
    end
  end

private


  def default_url_options
    { locale: I18n.locale }
  end


  def set_locale_to_default
    I18n.locale = I18n.default_locale
  end


  def form_locale
    (params['form_locale'] || I18n.locale).to_s
  end


  def available_locales
    @available_locales ||= I18n.available_locales.map(&:to_s).map(&:downcase).map{|v| v.sub('-', '_')}
  end


  def authenticate_user!
    unless user_signed_in?
      store_location
      redirect_to admin_sessions_path
    end
  end


  def admin?
    current_user&.admin_role?
  end


  # What a Guest is allowed to open. Anything else bounces them to analytics
  # rather than out of the admin entirely, so every link in the nav they see
  # actually works and a stray URL doesn't log them out.
  def only_permitted_section!
    return if admin?
    return if GUEST_SECTIONS.include?(controller_name)

    bounce_guest!
  end


  # For the handful of actions inside a Guest section that still change
  # something -- clearing a cache, say. Guests may look, not touch, so this
  # cannot lean on the section check: the section itself is permitted.
  def only_admin!
    return if admin?

    bounce_guest!
  end


  def bounce_guest!
    redirect_to admin_analytics_path(locale: params[:locale] || I18n.default_locale)
  end


  def permitted_admin_sections
    return ADMIN_SECTIONS if admin?

    ADMIN_SECTIONS.select { |section| GUEST_SECTIONS.include?(section.to_s) }
  end


  def current_user
    Current.user ||= authenticate_user_from_session
  end


  def authenticate_user_from_session
    User.enabled.find_by(id: session[:user_id])
  end


  def user_signed_in?
    current_user.present?
  end


  def login(user)
    Current.user = user
    reset_session
    user.touch(:last_logon_at)
    session[:user_id] = user.id
  end


  def logout(user)
    Current.user = nil
    reset_session
  end


  def redirect_back_or_default(default)
    redirect_to(session[:return_to] || default)
    session[:return_to] = nil
  end


  def store_location
    session[:return_to] = request.fullpath if request.get?
  end


end