# frozen_string_literal: true

# Implementation class for Cancan gem.  Instead of overriding this class, consider adding new permissions
# using the special +register_ability+ method which allows extensions to add their own abilities.
#
# See http://github.com/ryanb/cancan for more details on cancan.
require 'cancan'
module Spree
  class Ability
    include CanCan::Ability

    class_attribute :abilities
    self.abilities = Set.new

    attr_reader :user

    CUSTOM_ALIASES_MAP = {
      delete: :destroy,
      display: :read,
      new_action: :create,
      read: :show
    }.freeze

    # Allows us to go beyond the standard cancan initialize method which makes it difficult for engines to
    # modify the default +Ability+ of an application.  The +ability+ argument must be a class that includes
    # the +CanCan::Ability+ module.  The registered ability should behave properly as a stand-alone class
    # and therefore should be easy to test in isolation.
    def self.register_ability(ability)
      abilities.add(ability)
    end

    def self.remove_ability(ability)
      abilities.delete(ability)
    end

    def initialize(current_user)
      @user = current_user || Spree.user_class.new

      activate_permission_sets
      register_extension_abilities
    end

    def can?(action, *args)
      super(normalize_action(action), *args)
    end

    def model_adapter(model_class, action)
      super(model_class, normalize_action(action))
    end

    private

    def normalize_action(action)
      return action unless Spree::Config.use_custom_cancancan_actions

      normalized_action = CUSTOM_ALIASES_MAP.fetch(action, action)

      if action == :read
        Spree::Deprecation.warn <<~WARN, caller(3)
          The behavior of CanCanCan `:read` action alias will be changing in Solidus 3.0.
          The current alias is: `:show, :to => :read`,
          the new alias will be compliant with CanCanCan's default: `index, :show, :to => :read`
        WARN
      elsif CUSTOM_ALIASES_MAP.key? action
        Spree::Deprecation.warn <<~WARN, caller(3)
          Calling CanCanCan alias action #{action.inspect} is deprecated.
          In Solidus 3.0 non-standard CanCanCan action aliases will be replaced with default ones,
          please replace with #{normalized_action.inspect}.
        WARN
      end

      normalized_action
    end

    # Before, this was the only way to extend this ability. Permission sets have been added since.
    # It is recommended to use them instead for extension purposes if possible.
    def register_extension_abilities
      Ability.abilities.each do |clazz|
        ability = clazz.send(:new, user)
        merge(ability)
      end
    end

    def activate_permission_sets
      Spree::Config.roles.activate_permissions! self, user
    end
  end
end