Add `TomTom` class to communicate with their API

Provides an interface to communicate with the TomTom API. Currently
includes a method `#batch` to make a batch routing request
(https://developer.tomtom.com/online-routing/online-routing-documentation/batch-routing).

Left a bunch of development-related code in just to preserve my
in-progress stages. Originally I was told to use the matrix routing API,
but that turned out to not match what we wanted. Namely, matrix routing
would produce a table with every point routed with every other point. We
instead want routes of each segment in a line, in order (or, just the
diagonal of the matrix). Using the batch API allows us to get the routes
we need without doing unnecessary work.

Update the `WayCost` class to provide `departure` and `arrival` methods
as readers, and make `id` an optional parameter for now. (We still need
to figure out how we're dealing with ID.)

Refs #6095

2 files changed, 74 insertions, 1 deletions

diff --git a/lib/tom_tom.rb b/lib/tom_tom.rb
new file mode 100644
index 000000000..5343519fd
--- /dev/null
+++ b/lib/tom_tom.rb
@@ -0,0 +1,71 @@
+class TomTom
+  BASE_URL = 'https://api.tomtom.com'
+# https://api.tomtom.com/routing/1/matrix/xml?key=<APIKEY>&routeType=shortest&travelMode=truck
+  API_KEY = ''
+
+  def initialize
+    @connection = Faraday.new(
+      url: BASE_URL,
+      params: {
+        key: API_KEY
+      }
+    ) do |faraday|
+      faraday.use FaradayMiddleware::FollowRedirects, limit: 1
+      faraday.adapter Faraday.default_adapter
+    end
+  end
+
+  # Maximum size of matrix is 700 (number of origins multiplied by number of destinations), so examples of matrix dimensions are: 5x10, 10x10, 28x25 (it does not need to be square).
+  # def matrix(opts)
+  #   @connection.post do |req|
+  #     req.url '/routing/1/matrix/json'
+  #     req.params {
+  #       routeType: 'shortest',
+  #       travelMode: opts[:travel_mode],
+  #       routingOption: 'TODO'
+  #     }
+  #     req.body {
+  #       origins: [],
+  #       destinations: []
+  #     }
+  #   )
+  # end
+
+# Maximum number of batch items is 700.
+# {
+#   "batchItems": [
+#     {"query": "/calculateRoute/52.36006039665441,4.851064682006836:52.36187528311709,4.850560426712036/json?travelMode=car&routeType=shortest&traffic=true&departAt=now&maxAlternatives=0"},
+#     {"query": "/calculateRoute/52.36241907934766,4.850034713745116:52.36173769505809,4.852169752120972/json?travelMode=teleport&routeType=shortest&traffic=true&departAt=now"}
+#   ]
+# }
+  def batch(way_costs)
+    # TODO: figure out param assembly (maybe Net::HTTP has something?)
+    params = URI.encode_www_form({
+      travelMode: 'car',
+      routeType: 'shortest',
+      traffic: 'true',
+      departAt: 'now',
+      maxAlternatives: 0
+    })
+    batch_items = convert_way_costs_for_batch(way_costs).map do |locations|
+      {
+        query: "/calculateRoute/#{locations}/json?#{params}"
+      }
+    end
+
+    response = @connection.post do |req|
+      req.url '/routing/1/batch/json'
+      req.headers['Content-Type'] = 'application/json'
+      req.body = {
+        batchItems: batch_items
+      }.to_json
+    end
+  end
+
+  def convert_way_costs_for_batch(way_costs)
+    way_costs.map do |way_cost|
+      "#{way_cost.departure.lat},#{way_cost.departure.lng}" \
+      ":#{way_cost.arrival.lat},#{way_cost.arrival.lng}"
+    end
+  end
+end
diff --git a/lib/way_cost.rb b/lib/way_cost.rb
index b47836a28..32ced0205 100644
--- a/lib/way_cost.rb
+++ b/lib/way_cost.rb
@@ -1,10 +1,12 @@
 class WayCost
+  attr_reader :departure, :arrival
+
   def initialize(
     departure:,
     arrival:,
     distance: nil,
     time: nil,
-    id:,  # TODO: calculate ID automatically
+    id: nil  # TODO: calculate ID automatically
   )
     @departure = departure
     @arrival = arrival