SumOfUs/Champaign

# frozen_string_literal: true

module Donations
  module Utils
    extend self
    EURO_COUNTRY_CODES = %i[AL AD AT BY BE BA BG HR CY CZ DK EE FO FI FR DE GI GR HU IS IE IT LV LI LT LU MK MT MD MC NL NO PL PT RO RU SM RS SK SI ES SE UA VA RS IM RS ME].freeze # rubocop:disable Metrics/LineLength
    DEFAULT_CURRENCY = 'USD'

    def round_and_dedup(values)
      deduplicate(round(values))
    end

    def round(values)
      values.map do |value|
        value = value.to_f

        if value < 20
          value = value.round(0)
          if value.zero?
            1.to_f
          else
            value
          end
        else
          (value.to_f / 5).round * 5
        end
      end
    end

    def round_fundraising_goals(values)
      values.map do |value|
        value = value.to_f
        if value.zero?
          value
        else
          magnitude = Math.log10(value).floor
          base = (10**magnitude) / 2
          steps = value.to_f / (10**magnitude) * 2
          result = (steps.ceil * base)
          result >= 10 ? result : 10
        end
      end
    end

    def deduplicate(values)
      duplicates = values.group_by { |e| e }.select { |_k, v| v.size > 1 }.values.flatten

      safe = values - duplicates

      duplicates.each do |misfit|
        misfit += (misfit < 20 ? 1 : 5) while safe.include? misfit
        safe << misfit
      end
      safe.sort
    end

    def currency_from_country_code(country_code)
      return 'EUR' if EURO_COUNTRY_CODES.include?(country_code.to_s.to_sym)

      {
        US: 'USD',
        GB: 'GBP',
        NZ: 'NZD',
        AU: 'AUD',
        CA: 'CAD',
        CH: 'CHF',
        MX: 'MXN',
        AR: 'ARS',
        BR: 'BRL'
      }[country_code.to_s.to_sym] || DEFAULT_CURRENCY
    end
  end
end