Rework cities and countries visits calculation

app/jobs/reverse_geocoding_job.rb

@@ -12,7 +12,7 @@ class ReverseGeocodingJob < ApplicationJob
     result = Geocoder.search([point.latitude, point.longitude])
     return if result.blank?
 
-    point.update(
+    point.update!(
       city: result.first.city,
       country: result.first.country
     )

app/services/visits/calculate.rb

@@ -0,0 +1,82 @@
+# frozen_string_literal: true
+
+class Visits::Calculate
+  def initialize(points)
+    @points = points
+  end
+
+  def call
+    normalize_result(city_visits)
+  end
+
+  private
+
+  attr_reader :points
+
+  def group_points
+    points.sort_by(&:timestamp).reject { _1.city.nil? }.group_by(&:country)
+  end
+
+  def city_visits
+    group_points.transform_values do |grouped_points|
+      grouped_points
+        .group_by(&:city)
+        .transform_values { |city_points| identify_consecutive_visits(city_points) }
+    end
+  end
+
+  def identify_consecutive_visits(city_points)
+    visits = []
+    current_visit = []
+
+    city_points.each_cons(2) do |point1, point2|
+      time_diff = (point2.timestamp - point1.timestamp) / 60
+
+      if time_diff <= MIN_MINUTES_SPENT_IN_CITY
+        current_visit << point1 unless current_visit.include?(point1)
+        current_visit << point2
+      else
+        visits << create_visit(current_visit) if current_visit.size > 1
+        current_visit = []
+      end
+    end
+
+    visits << create_visit(current_visit) if current_visit.size > 1
+    visits
+  end
+
+  def create_visit(points)
+    {
+      city: points.first.city,
+      points:,
+      stayed_for: calculate_stayed_time(points),
+      last_timestamp: points.last.timestamp
+    }
+  end
+
+  def calculate_stayed_time(points)
+    return 0 if points.empty?
+
+    min_time = points.first.timestamp
+    max_time = points.last.timestamp
+    ((max_time - min_time) / 60).round
+  end
+
+  def normalize_result(hash)
+    hash.map do |country, cities|
+      {
+        country:,
+        cities: cities.values.flatten
+                      .select { |visit| visit[:stayed_for] >= MIN_MINUTES_SPENT_IN_CITY }
+                      .map do |visit|
+                        {
+                          city: visit[:city],
+                          points: visit[:points].count,
+                          timestamp: visit[:last_timestamp],
+                          stayed_for: visit[:stayed_for]
+                        }
+                      end
+      }
+    end.reject { |entry| entry[:cities].empty? }
+  end
+end