visualitypl / textris

  module Delivery

    class Mail < Textris::Delivery::Base

      class Mailer < ActionMailer::Base

        def notify(from, to, subject, body)

          mail :from => from, :to => to, :subject => subject, :body => body

        end

      end

      def deliver(to)

        template_vars = { :to_phone => to }

        from    = apply_template from_template,    template_vars

        to      = apply_template to_template,      template_vars

        subject = apply_template subject_template, template_vars

        body    = apply_template body_template,    template_vars

        ::Textris::Delivery::Mail::Mailer.notify(

          from, to, subject, body).deliver

      end

      private

      def from_template

        Rails.application.config.try(:textris_mail_from_template) ||

          "#{from_format}@%{env:d}.%{app:d}.com"

      end

      def to_template

        Rails.application.config.try(:textris_mail_to_template) ||

          "%{app:d}-%{env:d}-%{to_phone}[email protected]"

      end

      def subject_template

        Rails.application.config.try(:textris_mail_subject_template) ||

          "%{texter:dh} texter: %{action:h}"

      end

      def body_template

        Rails.application.config.try(:textris_mail_body_template) ||

          "%{content}"

      end

      def apply_template(template, variables)

        template.gsub(/\%\{[a-z_:]+\}/) do |match|

          directive = match.gsub(/[%{}]/, '')

          key       = directive.split(':').first

          modifiers = directive.split(':')[1] || ''

          content = get_template_interpolation(key, variables)

          content = apply_template_modifiers(content, modifiers.chars)

          content = 'unknown' unless content.present?

          content

        end

      end

      def get_template_interpolation(key, variables)

        case key

        when 'app', 'env'

          get_rails_variable(key)

        when 'texter', 'action', 'from_name', 'from_phone', 'content', 'twilio_messaging_service_sid'

          message.send(key)

        when 'media_urls'

          message.media_urls.join(', ')

        else

          variables[key.to_sym]

        end.to_s.strip

      end

      def get_rails_variable(var)

        case var

        when 'app'

          Rails.application.class.parent_name

        when 'env'

          Rails.env

        end

      end

      def apply_template_modifiers(content, modifiers)

        modifiers.each do |modifier|

          case modifier

          when 'd'

            content = content.underscore.dasherize

          when 'h'

            content = content.humanize.gsub(/[-_]/, ' ')

          when 'p'

            content = Phony.format(content) rescue content

          end

        end

        content

      end

    end

  end

end