require 'rubygems'
require 'hpricot'
require 'net/http'

module RedfinApi
  module Base
    class << self
      # this method is often overridden for testing purposes
      def http_get(url)
        Net::HTTP.get_response(URI.parse(url)).body
      end
      def http_get_json(url)
        response = http_get(url)
        response = response.strip[2..-3] # ignore the /* and */
        #        puts "response = #{response}"
        require 'json'
        json_hash = JSON.parse(response)
        # TODO symbolize_keys! here
        json_hash
      end
      def fetch_address(url)
        response = http_get(url)
        doc = Hpricot(response)
        address = {}
        address[:address_line_1] = (doc/'#address_line_1')[0].to_plain_text rescue nil
        address[:city] = (doc/'#address_line_2 .locality')[0].to_plain_text rescue nil
        address[:state] = (doc/'#address_line_2 .region')[0].to_plain_text rescue nil
        address[:zip] = (doc/'#address_line_2 .postal-code')[0].to_plain_text rescue nil
        address[:pin] = extract_pin(response)
        address
      end
      def extract_pin(html)
        /Parcel Identification Number:\s*(\d{10,14})/.match(html)[1].strip
      end
      def query_location(address)
        url = "http://www.redfin.com/stingray/do/query-location?location=#{URI.encode(address)}"
        location = http_get_json(url)
        # we either get a postSalesBuildings element or listings element
        item = location['pastSalesBuildings'].not_nil? ? location['pastSalesBuildings'][0] : location['listings'][0]
        address =  item['address']
        hash = {
          :lat => item['point']['lat'].to_s,
          :lon => item['point']['long'].to_s,
          :number => address['number'],
          :street_name => address['streetName'],
          :street_type => address['streetType'],
          :unit => address['unitValue'],
          :address_line_1 => "#{address['number']} #{address['streetName']} #{address['streetType']}",
          :city => address['city'],
          :state => address['state'],
          :zip => address['zip'],
        }
        if location['pastSalesBuildings'].not_nil?
          hash[:property_id] = item['id'].to_s
          hash[:url] = construct_redfin_url_from_address(hash)
        else
          hash[:listing_id] = item['id'].to_s
          hash.merge!(gis_id_search(hash[:listing_id]))
        end
        hash
      end
      def construct_redfin_url_from_address(location)
        "http://www.redfin.com/#{location[:state]}/#{location[:city].gsub(' ','-')}/#{location[:number]}-#{location[:street_name].gsub(' ','-')}-#{location[:street_type]}-#{location[:zip]}/home/#{location[:property_id]}"
      end
      def gis_id_search(listing_id)
        url ="http://www.redfin.com/stingray/do/gis-id-search?listing_id=#{listing_id}"
        response = http_get(url)
        response = response.strip[3..-4] # ignore the /*( and )*/
        require 'json'
        json_hash = JSON.parse(response)
        raise RuntimeError, "Failed to perform gis_id_search", json_hash if json_hash['resultCode' != 0]
        payload = json_hash['payload'][0]
        {
          :property_id => payload['property']['id'].to_s,
          :url =>  "http://www.redfin.com#{payload['URL']}",
        }
      end
    end
  end
end