# frozen_string_literal: true

module Sessions
  # Normalizza e applica fingerprint del client (OS, app, device, operatore)
  # sulla sessione, a create e/o a ogni telemetry.
  class ApplyClientInfo
    OS_VALUES = %w[android ios].freeze
    MAX_LEN = 80

    ATTRS = %i[
      client_os app_version app_build device_manufacturer device_model os_version carrier
    ].freeze

    def self.call(session, raw)
      new(session, raw).call
    end

    def initialize(session, raw)
      @session = session
      @raw = normalize_hash(raw)
    end

    def call
      attrs = extract_attrs
      return @session if attrs.empty?

      @session.assign_attributes(attrs)
      @session.save! if @session.persisted? && @session.changed?
      @session
    end

    private

    def normalize_hash(raw)
      return {} if raw.blank?

      data = raw.respond_to?(:to_unsafe_h) ? raw.to_unsafe_h : raw
      data = data.to_h if data.respond_to?(:to_h)
      data.with_indifferent_access
    rescue StandardError
      {}
    end

    def extract_attrs
      attrs = {}

      os = @raw[:os].presence || @raw[:client_os].presence
      os = os.to_s.downcase.strip
      attrs[:client_os] = os if OS_VALUES.include?(os)

      {
        app_version: %i[app_version version],
        app_build: %i[app_build build build_number],
        device_manufacturer: %i[device_manufacturer manufacturer],
        device_model: %i[device_model model],
        os_version: %i[os_version system_version],
        carrier: %i[carrier network_operator operator]
      }.each do |column, keys|
        value = keys.map { |k| @raw[k] }.find(&:present?)
        next if value.blank?

        attrs[column] = truncate(value.to_s.strip)
      end

      attrs
    end

    def truncate(value)
      value.bytesize <= MAX_LEN ? value : value.byteslice(0, MAX_LEN)
    end
  end
end