# frozen_string_literals: true

require "aws-sdk-s3"
require "mail"
require "shoryuken"

module Jobshop
  # Jobshop::Postmaster
  #
  # Reponsible for processing incoming email and dispatching it to its handler.
  class Postmaster
    include Shoryuken::Worker

    shoryuken_options queue: Jobshop.configuration.aws.incoming_email_queue

    def perform(sqs_msg, *)
      @event = S3EventMessage.new(sqs_msg.body) || return
      tempfile = Tempfile.new

      s3.get_object({ bucket: @event.bucket, key: @event.key }, target: tempfile)

      message = Mail.new(File.read(tempfile))
      recipient = Mail::Address.new(message.to.first)
      mailbox = recipient.local.split("+").first
      handler_address = "#{mailbox}@#{recipient.domain}"
      mailman = Mailman.find_by(address: handler_address)

      # TODO: If no mailman registered, look for domain. If no domain found
      # TODO: treat as spam.
      if mailman
        klass = mailman.handler_type.constantize
        handler = klass.new(message, organization: mailman.organization)
        success = handler.process
        if success
          copy_to(handler.processed_copy_prefix) if handler.copy_after_processing?
          delete_incoming if handler.delete_after_processing?
          sqs_msg.delete
        end
      else
        return
      end

    ensure
      @event = nil
      tempfile.close
      tempfile.unlink
    end

    def s3
      @s3 ||= Aws::S3::Client.new
    end

    def copy_to(prefix)
      key = prefix + "/" + @event.key.split("/").last

      s3.copy_object({
        copy_source: @event.bucket + "/" + @event.key,
        bucket: Jobshop.configuration.aws.s3_bucket,
        key: key
      }) || raise("Could not copy incoming rfq to processed folder")
    end

    def delete_incoming
      s3.delete_object({
        bucket: @event.bucket, key: @event.key
      }) || raise("Could not delete incoming email")
    end

    class S3EventMessage
      def initialize(message)
        @message = JSON.parse(message)

        return false unless records
      end

      def records
        @records ||= @message["Records"] || []
      end

      def bucket
        records.first.dig "s3", "bucket", "name"
      end

      def key
        records.first.dig "s3", "object", "key"
      end
    end
  end
end