# frozen_string_literal: true

require 'zh/version'
require 'open-uri'
require 'yajl/json_gem'

class Zh
  class Error < StandardError; end

  class << self
    RB_LT_25 = Gem::Version.new(RUBY_VERSION) < Gem::Version.new('2.5.0')
    TRADITIONAL_LOCALE = %i[tw hk].freeze
    SIMPLIFIED_LOCALE = %i[cn sg].freeze
    LOCALE = TRADITIONAL_LOCALE + SIMPLIFIED_LOCALE

    # sg, cn are Simplified Chinese, tw, hk are Traditional Chinese
    LOCALE.each do |method|
      define_method "to_#{method}" do |message|
        converter(method, message)
      end
    end

    def converter(method, message)
      default_locale_data = locale_data(method)
      default_locale_data.each_key { |k| message.gsub!(k, default_locale_data[k]) }
      hanx_data = locale_data(TRADITIONAL_LOCALE.include?(method) ? 'hant' : 'hans')
      hanx_data.each_key { |k| message.gsub!(k, hanx_data[k]) }
      message
    end

    def update_data
      %i[cn sg tw hk hans hant].each do |locale|
        data = locale_data(locale)
        url = "https://zh.wikipedia.org/w/index.php?title=MediaWiki:Conversiontable/zh-#{locale}&action=raw&templates=expand"
        table = RB_LT_25 ? open(url).read : URI.open(url).read
        table.lines do |line|
          matches = line.match(%r{^[*"]([^"=]+)"?\s*=>\s*"?([^\s/"]+)\s?.*"?[;,]$})
          data[matches[1].strip] = matches[2].strip if matches
        end
        write_to_json(locale, data)
      end
      true
    end

    private

    def locale_data(locale)
      json = File.new(__dir__ + "/data/zh-#{locale}.json", 'r')
      parser = Yajl::Parser.new
      parser.parse(json)
    end

    def write_to_json(locale, data)
      file = File.open(__dir__ + "/data/zh-#{locale}.json", 'w')
      file.write(data.to_json)
    rescue IOError => e
      puts "An error occurred: #{$ERROR_INFO}"
    ensure
      file&.close
    end
  end
end