class CvrInformation

  require 'open-uri'
  require 'nokogiri'
  
  class CompanyNotFoundInCvr < Exception ; end
  
  class << self
    
    def get_company_from_vat_number(cvr)
      uri = "http://cvr.dk/Site/Forms/PublicService/DisplayCompany.aspx?cvrnr=#{cvr}"
      extract_company_from_cvr(uri)
    end
    
    def get_company_from_name(name)
      uri = URI.escape("http://cvr.dk/Site/Forms/CompanySearch/CompanySearch.aspx?navn=#{name}")    
      extract_company_from_cvr(uri)
    end
    
    private
    
      def extract_company_from_cvr(uri)
        doc = Nokogiri::HTML(open(uri))
        (doc/"div.titletext").inner_html.strip.empty? and raise CompanyNotFoundInCvr
        company = Company.new
        company.name = extract_name(doc)
        company.address = extract_address(doc)
        company.zip = extract_zip(doc)
        company.city = extract_city(doc)
        company.vat_number = extract_vat_number(doc)
        company.telephone = extract_telephone(doc)
        company.email = extract_email(doc)
        return company
      end
    
      def extract_name(doc)
        (doc/"div.titletext").inner_html.strip
      end
      
      def extract_address(doc)
        (doc/"tr:contains('Adresse')/td.fieldvalue").inner_html =~ /^(.+)<br\W+\d{4}\W+(.+)$/
        $~[1].strip.gsub("<br />", ", ")
      end

      def extract_zip(doc)
        (doc/"tr:contains('Adresse')/td.fieldvalue").inner_html =~ /(\d{4})\W+(.+)$/
        $~[1].strip
      end
      
      def extract_city(doc)
        (doc/"tr:contains('Adresse')/td.fieldvalue").inner_html =~ /(\d{4})\W+(.+)$/
        $~[2].strip
      end

      def extract_vat_number(doc)
        (doc/"tr:contains('Cvr-nr')/td.fieldvalue").inner_html.strip
      end

      def extract_email(doc)
        (doc/"tr:contains('Email')/td.fieldvalue").inner_html.strip
      end

      def extract_telephone(doc)
        (doc/"tr:contains('Telefon')/td.fieldvalue").inner_html.strip
      end
    
  end
    
  class Company
    
    attr_accessor :name, :address, :zip, :city, :country, :vat_number, :ean, :telephone, :email
    
  end

end