gem "servactory"

class UserService::Authenticate < Servactory::Base
  input :email, type: String
  input :password, type: String

  output :user, type: User

  make :authenticate!

  private

  def authenticate!
    if (user = User.authenticate_by(email: inputs.email, password: inputs.password)).present?
      outputs.user = user
    else
      fail!(message: "Authentication failed", meta: { email: inputs.email })
    end
  end
end

class SessionsController < ApplicationController
  def create
    service = UserService::Authenticate.call(**session_params)

    if service.success?
      session[:current_user_id] = service.user.id
      redirect_to service.user
    else
      flash.now[:alert] = service.error.message
      render :new, status: :unprocessable_entity
    end
  end

  private

  def session_params
    params.require(:session).permit(:email, :password)
  end
end