class PatientMerger

# File app/lib/patient_merger.rb, line 196
  def self.call(...) = new(...).call

  private_class_method :new

  private

  attr_reader :patient_to_keep, :patient_to_destroy
end

# File app/lib/patient_merger.rb, line 4
def initialize(to_keep:, to_destroy:, user: nil)
  @patient_to_keep = to_keep
  @patient_to_destroy = to_destroy
  @user = user
end

# File app/lib/patient_merger.rb, line 10
def call
  vaccination_record_ids = []

  ActiveRecord::Base.transaction do
    patient_to_destroy.access_log_entries.update_all(
      patient_id: patient_to_keep.id
    )

    patient_to_keep.archive_reasons.find_each do |archive_reason|
      unless patient_to_destroy.archive_reasons.exists?(
               team_id: archive_reason.team_id
             )
        archive_reason.destroy!
      end
    end

    patient_to_destroy.archive_reasons.destroy_all

    patient_to_destroy.attendance_records.find_each do |attendance_record|
      if patient_to_keep.attendance_records.exists?(
           location_id: attendance_record.location_id,
           date: attendance_record.date
         )
        attendance_record.destroy!
      else
        attendance_record.update_column(:patient_id, patient_to_keep.id)
      end
    end

    patient_to_destroy.consent_notifications.update_all(
      patient_id: patient_to_keep.id
    )
    patient_to_destroy.consents.update_all(patient_id: patient_to_keep.id)

    patient_to_destroy.clinic_notifications.update_all(
      patient_id: patient_to_keep.id
    )

    patient_to_destroy.notes.update_all(patient_id: patient_to_keep.id)

    patient_to_destroy.notify_log_entries.update_all(
      patient_id: patient_to_keep.id
    )

    patient_to_destroy.gillick_assessments.update_all(
      patient_id: patient_to_keep.id
    )

    patient_to_destroy.patient_merge_log_entries.update_all(
      patient_id: patient_to_keep.id
    )

    patient_to_destroy.patient_specific_directions.update_all(
      patient_id: patient_to_keep.id
    )

    patient_to_destroy.pds_search_results.update_all(
      patient_id: patient_to_keep.id
    )

    patient_to_destroy.pre_screenings.update_all(
      patient_id: patient_to_keep.id
    )

    patient_to_destroy.school_moves.find_each do |school_move|
      if patient_to_keep.school_moves.exists?
        school_move.destroy!
      else
        school_move.update_column(:patient_id, patient_to_keep.id)
      end
    end

    patient_to_destroy.school_move_log_entries.update_all(
      patient_id: patient_to_keep.id
    )

    patient_to_destroy.session_notifications.update_all(
      patient_id: patient_to_keep.id
    )

    patient_to_destroy.triages.update_all(patient_id: patient_to_keep.id)

    vaccination_record_ids =
      patient_to_destroy.vaccination_records.with_discarded.ids
    patient_to_destroy.vaccination_records.with_discarded.update_all(
      patient_id: patient_to_keep.id
    )

    patient_to_destroy.parent_relationships.find_each do |relationship|
      if patient_to_keep.parent_relationships.exists?(
           parent_id: relationship.parent_id
         )
        relationship.destroy!
      else
        relationship.update_column(:patient_id, patient_to_keep.id)
      end
    end

    patient_to_destroy.patient_locations.each do |patient_location|
      if patient_to_keep.patient_locations.exists?(
           academic_year: patient_location.academic_year,
           location_id: patient_location.location_id
         )
        next
      end
      patient_location.update_column(:patient_id, patient_to_keep.id)
    end

    PatientLocation.where(patient: patient_to_destroy).destroy_all

    patient_to_destroy
      .patient_programme_vaccinations_searches
      .find_each do |search|
      existing_search =
        patient_to_keep.patient_programme_vaccinations_searches.find_by(
          programme_type: search.programme_type
        )

      if existing_search
        if existing_search.last_searched_at > search.last_searched_at
          search.last_searched_at = existing_search.last_searched_at
        end
        existing_search.destroy!
      end
      search.update!(patient_id: patient_to_keep.id)
    end

    patient_to_destroy.changesets.update_all(patient_id: nil)

    patient_to_destroy.class_imports.each do |import|
      unless patient_to_keep.class_imports.include?(import)
        patient_to_keep.class_imports << import
      end
    end

    patient_to_destroy.cohort_imports.each do |import|
      unless patient_to_keep.cohort_imports.include?(import)
        patient_to_keep.cohort_imports << import
      end
    end

    patient_to_destroy.immunisation_imports.each do |import|
      unless patient_to_keep.immunisation_imports.include?(import)
        patient_to_keep.immunisation_imports << import
      end
    end

    patient_to_destroy.class_imports.clear
    patient_to_destroy.cohort_imports.clear
    patient_to_destroy.immunisation_imports.clear

    patient_to_destroy.patient_teams.find_each do |patient_team_to_destroy|
      patient_team_to_keep =
        patient_to_keep.patient_teams.find_or_initialize_by(
          team_id: patient_team_to_destroy.team_id
        )

      patient_team_to_keep.sources =
        (
          patient_team_to_keep.sources + patient_team_to_destroy.sources
        ).uniq.sort

      patient_team_to_keep.save!
    end

    PatientMergeLogEntry.create!(
      patient: patient_to_keep,
      merged_patient_id: patient_to_destroy.id,
      merged_patient_name: patient_to_destroy.full_name,
      merged_patient_dob: patient_to_destroy.date_of_birth,
      merged_patient_nhs_number: patient_to_keep.nhs_number,
      user: @user
    )

    patient_to_destroy.reload.destroy!

    PatientStatusUpdater.call(patient: patient_to_keep)
  end

  SearchVaccinationRecordsInNHSJob.perform_async(patient_to_keep.id)

  VaccinationRecord.where(
    id: vaccination_record_ids
  ).sync_all_to_nhs_immunisations_api
end