require 'ecoportal/api/v1/job/status'
require 'ecoportal/api/v1/job/awaiter'

module Ecoportal
  module API
    class V1
      class Job
        attr_reader :client, :person_class

        # @param client [Common::Client] a `Common::Client` object that holds the configuration of the api connection.
        # @return [People] an instance object ready to make people api requests.
        def initialize(client, person_class:)
          @client       = client
          @person_class = person_class
          @created      = false
        end

        # Allows to preserve the learned througoutput
        def new
          self.class.new(client, person_class: person_class).tap do |out|
            out.awaiter = @awaiter
          end
        end

        def created?
          @created
        end

        # @return [Ecoportal::API::Common::Response] the results of the batch job
        def batch(recover: false)
          raise_if_already_launched! unless recover

          @operation ||= Common::BatchOperation.new(
            "/people",
            person_class,
            logger: client.logger
          )

          yield operation unless recover

          total   = operation.count
          job_id  = create(operation, recover: recover)
          stat    = awaiter(
            job_id: job_id,
            total:  total
          ).await_completion!

          job_result(job_id, operation) if stat&.complete?(total)
        end

        def status(job_id)
          response = client.get("/people/job/#{CGI.escape(job_id)}/status")
          body     = response && body_data(response.body)

          msg      = "Status error (#{response.status}) - "
          msg     << "Errors: #{body}"
          raise msg unless response.success?

          Status.new(*body.values_at(*%w[id complete errored progress]))
        end

        protected

        attr_writer :awaiter

        def awaiter(job_id:, total:, preserve: true)
          return @awaiter = Awaiter.new(self, job_id: job_id, total: total) unless preserve && @awaiter

          @awaiter = @awaiter.new(job_id: job_id, total: total)
        end

        private

        attr_reader :operation

        def operations
          @operations ||= {}
        end

        def job_operation(job_id)
          operations[job_id]
        end

        def raise_if_already_launched!
          return unless created?

          msg  = "Missusage: job was already created."
          msg << " Can't call batch more than once"
          raise msg
        end

        # @return [Ecoportal::API::Common::Response] the results of the batch job
        def job_result(job_id, operation)
          client.get("/people/job/#{CGI.escape(job_id)}").tap do |response|
            operation.process_response(response)
          end
        end

        # @return [String] the `id` of the created batch job
        def create(operation, recover: false)
          raise_if_already_launched! unless recover

          job_id = nil

          client.post("/people/job", data: operation.as_json).tap do |response|
            job_id = body_data(response.body)["id"] if response.success?

            next if job_id

            msg  = "Could not create job - Error (#{response.status}): "
            msg << body_data(response.body).to_s
            raise msg
          end

          if job_id
            @created = true
            operations[job_id] = operation
          end

          job_id
        end

        # Hook for other api versions to obtain the raw data of a response
        # @note this was introduced to allow `v2` to reuse this class
        def body_data(body)
          body
        end
      end
    end
  end
end