# frozen_string_literal: true

require 'fugit'

module Sail
  # Setting
  class Setting < ApplicationRecord
    extend Sail::ValueCast
    FULL_RANGE = (0...100).freeze
    SETTINGS_PER_PAGE = 8
    AVAILABLE_MODELS = Dir["#{Rails.root}/app/models/*.rb"]
                         .map { |dir| dir.split('/').last.camelize.gsub('.rb', '') }.freeze

    validates_presence_of :name, :value, :cast_type
    validates_uniqueness_of :name
    enum cast_type: %i[integer string boolean range array float
                       ab_test cron obj_model date uri].freeze

    validate :value_is_within_range, if: -> { range? }
    validate :value_is_true_or_false, if: -> { boolean? || ab_test? }
    validate :cron_is_valid, if: -> { cron? }
    validate :model_exists, if: -> { obj_model? }
    validate :date_is_valid, if: -> { date? }
    validate :uri_is_valid, if: -> { uri? }

    scope :paginated, ->(page) do
      select(:name, :description, :value, :cast_type, :updated_at)
        .offset(page.to_i * SETTINGS_PER_PAGE)
        .limit(SETTINGS_PER_PAGE)
    end

    scope :by_name, ->(name) { name.present? ? where('name LIKE ?', "%#{name}%") : all }

    def self.get(name)
      Rails.cache.fetch("setting_get_#{name}", expires_in: Sail.configuration.cache_life_span) do
        cast_setting_value(
          Setting.select(:value, :cast_type).where(name: name).first
        )
      end
    end

    def self.set(name, value)
      setting = Setting.find_by(name: name)
      value_cast = cast_value_for_set(setting, value)
      success = setting.update_attributes(value: value_cast)
      Rails.cache.delete("setting_get_#{name}") if success
      [setting, success]
    end

    def self.cast_setting_value(setting)
      return if setting.nil?
      send("#{setting.cast_type}_get", setting.value)
    end

    def self.cast_value_for_set(setting, value)
      send("#{setting.cast_type}_set", value)
    end

    def display_name
      name.gsub(/[^a-zA-Z\d]/, ' ').titleize
    end

    private

    def model_exists
      errors.add(:invalid_model, 'Model does not exist') unless AVAILABLE_MODELS.include?(value)
    end

    def value_is_true_or_false
      if Sail::ConstantCollection::STRING_BOOLEANS.exclude?(value)
        errors.add(:not_a_boolean_error,
                   "Boolean settings only take values inside #{Sail::ConstantCollection::STRING_BOOLEANS}")
      end
    end

    def value_is_within_range
      unless FULL_RANGE.cover?(self.class.cast_setting_value(self))
        errors.add(:outside_range_error,
                   "Range settings only take values inside range #{FULL_RANGE}")
      end
    end

    def date_is_valid
      DateTime.parse(value)
    rescue ArgumentError
      errors.add(:invalid_date, 'Date format is invalid')
    end

    def cron_is_valid
      if Fugit::Cron.new(value).nil?
        errors.add(:invalid_cron_string,
                   "Setting value is not a valid cron")
      end
    end

    def uri_is_valid
      URI(value)
    rescue URI::InvalidURIError
      errors.add(:invalid_uri, "URI value is invalid")
    end
  end
end