# frozen_string_literal: true

module Logux
  class ClassFinder
    attr_reader :action, :meta

    def initialize(action:, meta:)
      @action = action
      @meta = meta
    end

    def find_action_class
      "#{class_namespace}::#{class_name}".constantize
    rescue NameError
      message =
        "Unable to find action #{class_name.camelize}.\n" \
        "Should be in app/logux/#{class_namespace.downcase}/#{class_path}.rb"
      raise_error_for_failed_find(message)
    end

    def find_policy_class
      "Policies::#{class_namespace}::#{class_name}".constantize
    rescue NameError
      message =
        "Unable to find action policy #{class_name.camelize}.\n" \
        "Should be in app/logux/#{class_namespace.downcase}/#{class_path}.rb"
      raise_error_for_failed_find(message)
    end

    def class_name
      if subscribe?
        action.channel_name.camelize
      else
        action.type.split('/')[0..-2].map(&:camelize).join('::')
      end
    end

    private

    def class_namespace
      subscribe? ? 'Channels' : 'Actions'
    end

    def subscribe?
      action.type == 'logux/subscribe'
    end

    def action?
      !subscribe?
    end

    def class_path
      "#{class_namespace}::#{class_name}".underscore
    end

    def raise_error_for_failed_find(message)
      exception_class = action? ? UnknownActionError : UnknownChannelError
      raise exception_class.new(message, meta: meta)
    end
  end
end