geokit/geokit

module Geokit
  module Geocoders
    class FCCGeocoder < Geocoder
      self.secure = true

      private

      # Template method which does the reverse-geocode lookup.
      def self.do_reverse_geocode(latlng)
        latlng = LatLng.normalize(latlng)
        url = "#{protocol}://geo.fcc.gov/api/census/block/find?format=json&latitude=#{Geokit::Inflector.url_escape(latlng.lat.to_s)}&longitude=#{Geokit::Inflector.url_escape(latlng.lng.to_s)}"
        process :json, url
      end

      # Template method which does the geocode lookup.
      #
      # ==== EXAMPLES
      # ll=Geokit::LatLng.new(40, -85)
      # Geokit::Geocoders::FCCGeocoder.geocode(ll) #

      # JSON result looks like this
      # => {"County"=>{"name"=>"Wayne", "FIPS"=>"18177"},
      # "Block"=>{"FIPS"=>"181770103002004"},
      # "executionTime"=>"0.099",
      # "State"=>{"name"=>"Indiana", "code"=>"IN", "FIPS"=>"18"},
      # "status"=>"OK"}

      def self.parse_json(results)
        if results.key?('Err') && results['Err']['msg'] == 'There are no results for this location'
          return GeoLoc.new
        end
        # this should probably be smarter.
        raise Geokit::Geocoders::GeocodeError if !results['status'] == 'OK'

        loc = new_loc
        loc.success       = true
        loc.precision     = 'block'
        loc.country_code  = 'US'
        loc.district      = results['County']['name']
        loc.district_fips = results['County']['FIPS']
        loc.county        = results['County']['name']
        loc.state         = results['State']['code']
        loc.state_fips    = results['State']['FIPS']
        loc.block_fips    = results['Block']['FIPS']
        loc
      end
    end
  end
end