Convert Stats NZ Urban/Rural KML to Geoguessr map regions JSON

kml2geoguessr.rb

# Get the file from https://datafinder.stats.govt.nz/layer/105158-urban-rural-2021-generalised/
# USAGE: ruby kml2geoguessr.rb urban-rural-2021-generalised.kml > rural-nz.geoguesser.json
require "nokogiri"
require "json"

TYPES = [
  # "Major urban area",
  # "Large urban area",
  "Medium urban area",
  "Small urban area",
  # "Rural settlement"
]

doc = Nokogiri::XML(ARGF)

places = doc.css("Placemark").select { |e| TYPES.include?(e.at("SimpleData[name=IUR2021_V1_00_NAME]").content) }
warn places.count.to_s + " places selected."

# don't judge me, i'm actually a professional i promise
coordinates = places.map { |p|
  {
    coordinates: p.at("MultiGeometry Polygon outerBoundaryIs LinearRing coordinates").text.strip.split.each_with_index.map { |c, i| lng, lat = c.split(","); { lat: lat.to_f, lng: lng.to_f } }
  }
}

warn "Coordinates: " + coordinates.sum { |c| c[:coordinates].size }.to_s

puts JSON.generate(coordinates)

# From here, I use a HTTP client to POST the map JSON based on requests I captured from the browser