defmodule Gulib.Const do

  #### http://elixir-lang.org/docs/master/elixir/Regex.html
  @ip_regex ~r"^(25[0-5]|2[0-4][0-9]|[0-1]{1}[0-9]{2}|[1-9]{1}[0-9]{1}|[1-9])\.(25[0-5]|2[0-4][0-9]|[0-1]{1}[0-9]{2}|[1-9]{1}[0-9]{1}|[1-9]|0)\.(25[0-5]|2[0-4][0-9]|[0-1]{1}[0-9]{2}|[1-9]{1}[0-9]{1}|[1-9]|0)\.(25[0-5]|2[0-4][0-9]|[0-1]{1}[0-9]{2}|[1-9]{1}[0-9]{1}|[0-9])$"
  @scan_url_regex ~r"((mailto|http|https|thunder|ftp|sftp|svn)\:\/\/|www.)[0-9a-zA-Z]([-.\w]*[0-9a-zA-Z])*(:(0-9)*)*(\/?)([a-zA-Z0-9\-\=\&\.\?\,\'\/\\\+&%\$#_]*)?"
  @email_regex ~r"\A([^@\s]+)@((?:[-a-z0-9]+\.)+[a-z]{2,})\z"
  @pure_number_regex ~r"\A[0-9]*\z"
  @words_regex ~r/[\w-_0-9]+/u
  @match_url_regex ~r"^((mailto|http|https|thunder|ftp|sftp|svn)\:\/\/|www.)[0-9a-zA-Z]([-.\w]*[0-9a-zA-Z])*(:(0-9)*)*(\/?)([a-zA-Z0-9\-\=\&\.\?\,\'\/\\\+&%\$#_]*)?$"
  @mobile_number_formats [
    cn: %{
      length: 11,
      regex: ~r/^(0|86|17951)?(13[0-9]|15[0-9]|17[0-9]|18[0-9]|14[0-9])[0-9]{8}$/u
    }
  ]

  @spider_regex ~r(spider|bot|crawler|ysearch\/slurp)
  def spider_regex, do: @spider_regex

  @doc "IO地址的正则表达式"
  def ip_regex, do: @ip_regex

  @doc "电子邮箱的正则表达式"
  def email_regex, do: @email_regex

  @doc "纯数字的正则表达式"
  def pure_number_regex, do: @pure_number_regex

  @doc "文字正则"
  def words_regex, do: @words_regex

  @doc "只匹配文字，下划线和中划线, 数字"
  def name_regex_match?(str) do
    (String.replace(str, @words_regex, "") |> String.length) == 0
  end

  @doc "半角和全角得空格"
  def space_strings, do: [" ", "　"]

  @doc "匹配URL的正则表达式"
  def match_url_regex, do: @match_url_regex

  @doc """
  扫描出URL的正则表达式
  ```
  eg: 
  * https://msdn.microsoft.com/en-us/library/ff650303.aspx#paght000001_commonregularexpressions
  * http://stackoverflow.com/questions/1323283/how-to-match-url-in-c
  ```
  """
  def scan_url_regex, do: @scan_url_regex

  @doc "手机号码的正则表达式，按照国家归属"
  def mobile_number_formats, do: @mobile_number_formats

  def normalize_mobile_number!(country_key, mobile_number) do
    if mobile_number_format = @mobile_number_formats |> Gulib.get(country_key) do
      length_require = mobile_number_format |> Gulib.get(:length)

      mobile_number =
        mobile_number
        |> Gulib.to_s
        |> String.trim

      length = String.length(mobile_number)

      cond do
        length > length_require -> String.slice(mobile_number, -length_require, length_require)
        true -> mobile_number
      end
    else
      mobile_number
    end
  end

  def mobile_number_match?(nil, _mobile_number), do: false
  def mobile_number_match?(_country_key, nil), do: false
  def mobile_number_match?(country_key, mobile_number) do
    if mobile_number_format = @mobile_number_formats |> Gulib.get(country_key) do
      Regex.match?(mobile_number_format[:regex], mobile_number)
    else
      false
    end
  end

end