module Scrivito
  #
  # This module lets you change the URL of a binary CMS object for the purpose of
  # fetching the binary data from a different location (e.g. via a proxy or from a mirror).
  #
  #
  # @api public
  #
  module BinaryRewrite
    def self.call(request, url)
      change_url_callback = request.env["SCRIVITO_BINARY_URL_CALLBACK"]
      url = change_url_callback.call(url) if change_url_callback
      url
    end
    #
    # You can, for example, have the URLs of images, etc., point to your desired
    # domain instead of to the CDN Scrivito uses.
    #
    # @api public
    #
    # @param request [ActionDispatch::Request]
    # @param block [Proc] block change default CDN url of current binary obj
    #
    # @example
    #   Scrivito::BinaryRewrite.enable_for(request) do |binary_url|
    #     binary_url.sub(
    #       "https://scrivito-public-cdn.s3-eu-west-1.amazonaws.com/",
    #       "https://my.reverse.proxy.com/")
    #   end
    #
    def self.enable_for(request, &block)
      request.env["SCRIVITO_BINARY_URL_CALLBACK"] = block
    end
  end
end