dat stank

gistfile1.rb

class Stank
  MONTHS = {
    "january"   => 1,
    "jan"       => 1,
    "february"  => 2,
    "feb"       => 2,
    "march"     => 3,
    "mar"       => 3,
    "april"     => 4,
    "apr"       => 4,
    "may"       => 5,
    "june"      => 6,
    "july"      => 7,
    "august"    => 8,
    "aug"       => 8,
    "september" => 9,
    "sept"      => 9,
    "october"   => 10,
    "oct"       => 10,
    "november"  => 11,
    "nov"       => 11,
    "december"  => 12,
    "dec"       => 12
  }

  def self.parse(str)
    new(str).date
  end

  def initialize(str)
    @str = str.present? ? str.strip.gsub('.', '') : nil
  end

  def date
    return nil unless @str

    year_date || chronic_date || josh_date
  end

  def year_only?
    @str.length == 4 && /\d{4}/.match(@str)
  end

  def year_date
    @year_date ||= begin
      Date.new(@str.to_i) if year_only?
    end
  end

  def chronic_date
    @chronic_date ||= Chronic.parse(@str)
  end

  def josh_date
    @josh_date ||= begin
      Date.new(josh_year, josh_month || 1) if josh_year
    end
  end

  def josh_year
    @josh_year ||= begin
      match = /\d{4}/.match(@str)
      match[0].to_i if match
    end
  end

  def josh_month
    @josh_month ||= begin
      MONTHS[MONTHS.keys.detect{|month| @str.downcase.include?(month)}]
    end
  end
end