# frozen_string_literal: true

class ExperimentMember
  include ActiveModel::Model

  attr_accessor :user_id, :user_role_id
  attr_reader :current_user, :experiment,
              :user, :project, :user_role,
              :user_assignment

  def initialize(current_user, experiment, project, user = nil, user_assignment = nil)
    @experiment = experiment
    @current_user = current_user
    @project = project
    @user_assignment = user_assignment

    if user
      @user = user
      @user_role = UserAssignment.find_by(assignable: experiment, user: user)&.user_role
    end
  end

  def handle_change(params)
    prepare_data(params)
    ActiveRecord::Base.transaction do
      if destroy_role?
        user_assignment.destroy
      elsif user_assignment.present?
        user_assignment.update!(user_role: user_role)
      else
        UserAssignment.create!(
          assignable: experiment,
          user: user,
          user_role: user_role,
          assigned_by: current_user
        )
      end
      log_change_activity
    end
  end

  def update(params)
    prepare_data(params)

    ActiveRecord::Base.transaction do
      user_assignment.update!(user_role: user_role)
      log_change_activity
    end
  end

  def create(params)
    prepare_data(params)

    ActiveRecord::Base.transaction do
      @user_assignment = UserAssignment.create!(
        assignable: experiment,
        user: user,
        user_role: user_role,
        assigned_by: current_user
      )
      log_change_activity
    end
  end

  def destroy
    ActiveRecord::Base.transaction do
      user_assignment.destroy
      log_change_activity
    end
  end

  private

  def prepare_data(params)
    self.user_role_id = params[:user_role_id]
    self.user_id = params[:user_id]

    @user = @project.users.find(user_id)
    @user_role = UserRole.find_by(id: user_role_id)
    @user_assignment ||= UserAssignment.find_by(assignable: experiment, user: user)
  end

  def log_change_activity
    Activities::CreateActivityService.call(
      activity_type: :change_user_role_on_experiment,
      owner: current_user,
      subject: experiment,
      team: project.team,
      project: project,
      message_items: {
        experiment: experiment.id,
        user_target: user.id,
        role: user_role.name
      }
    )
  end

  def destroy_role?
    (user_assignment.present? && user_role.nil?) ||
      UserAssignment.find_by(assignable: project, user: user)&.user_role == user_role
  end
end