Use structs instead of hashes for shipments

Gemfile.lock

@@ -9,6 +9,7 @@ GEM
     ast (2.4.2)
     base64 (0.1.1)
     diff-lcs (1.5.0)
+    docile (1.4.1)
     json (2.6.3)
     json (2.6.3-java)
     language_server-protocol (3.17.0.3)
@@ -54,6 +55,12 @@ GEM
       rubocop (>= 1.7.0, < 2.0)
       rubocop-ast (>= 0.4.0)
     ruby-progressbar (1.13.0)
+    simplecov (0.22.0)
+      docile (~> 1.1)
+      simplecov-html (~> 0.11)
+      simplecov_json_formatter (~> 0.1)
+    simplecov-html (0.12.3)
+    simplecov_json_formatter (0.1.4)
     standard (1.31.0)
       language_server-protocol (~> 3.17.0.2)
       lint_roller (~> 1.0)
@@ -70,12 +77,14 @@ GEM
 
 PLATFORMS
   arm64-darwin-22
+  arm64-darwin-23
   universal-java-17
 
 DEPENDENCIES
   planet_express_express!
   rake (~> 13.0)
   rspec (~> 3.0)
+  simplecov (~> 0.22.0)
   standard (~> 1.3)
 
 BUNDLED WITH

lib/planet_express_express/discount_budget.rb

@@ -9,10 +9,10 @@ module PlanetExpressExpress
         available_budget = @limit_per_month
 
         month.each do |shipment|
-          if shipment[:discount] > available_budget
+          if shipment.discount > available_budget
-            shipment[:discount] = available_budget
+            shipment.discount = available_budget
           end
-          available_budget -= shipment[:discount]
+          available_budget -= shipment.discount
         end
       end
     end

lib/planet_express_express/formatter.rb

@@ -8,7 +8,7 @@ module PlanetExpressExpress
       shipments[:all].each do |month|
         month.each do |shipment|
           @io.write(
-            "#{shipment[:date].iso8601} #{shipment[:size]} #{shipment[:provider]} #{(shipment[:price] - shipment[:discount]).to_s.rjust(3, "0").insert(-3, ".")} #{shipment[:discount].zero? ? "-" : shipment[:discount].to_s.rjust(3, "0").insert(-3, ".")}\n"
+            "#{shipment.date.iso8601} #{shipment.size} #{shipment.provider} #{(shipment.price - shipment.discount).to_s.rjust(3, "0").insert(-3, ".")} #{shipment.discount.zero? ? "-" : shipment.discount.to_s.rjust(3, "0").insert(-3, ".")}\n"
           )
         end
       end

lib/planet_express_express/rules.rb

@@ -23,7 +23,7 @@ module PlanetExpressExpress
 
           lp_count += 1
           if lp_count == 3
-            shipment[:discount] = shipment[:price]
+            shipment.discount = shipment.price
             break
           end
         end
@@ -33,7 +33,7 @@ module PlanetExpressExpress
     def s_rule(monthly_shipments)
       monthly_shipments.each do |month|
         month.each do |shipment|
-          shipment[:discount] += shipment[:price] - lowest_s_price
+          shipment.discount += shipment.price - lowest_s_price
         end
       end
     end

lib/planet_express_express/shipment_reader.rb

@@ -1,6 +1,15 @@
 module PlanetExpressExpress
   require "date"
   class ShipmentReader
+    Shipment = Struct.new(
+      :id,
+      :date,
+      :size,
+      :provider,
+      :price,
+      :discount,
+      keyword_init: true
+    )
     def initialize(prices)
       @prices = prices
       @id = 0
@@ -21,14 +30,14 @@ module PlanetExpressExpress
       io.each_line do |line|
         shipment = parse(line)
 
-        if shipment[:date].year != current_year || shipment[:date].month != current_month
+        if shipment.date.year != current_year || shipment.date.month != current_month
           close_month(shipments)
         end
-        shipments[shipment[:size]].last.push(shipment)
+        shipments[shipment.size].last.push(shipment)
         shipments[:all].last.push(shipment)
 
-        current_year = shipment[:date].year
+        current_year = shipment.date.year
-        current_month = shipment[:date].month
+        current_month = shipment.date.month
       end
 
       shipments
@@ -47,19 +56,18 @@ module PlanetExpressExpress
     def parse(line)
       parts = line.split(" ")
 
-      shipment = {
+      shipment = Shipment.new(
         id: sequential_id,
         date: Date.strptime(parts[0], "%Y-%m-%d"),
         size: parts[1]&.to_sym,
         provider: parts[2]&.to_sym,
         price: 0,
-        discount: 0,
+        discount: 0
-        valid: true
+      )
-      }
 
-      shipment[:price] = prices[
+      shipment.price = prices[
         [
-          shipment[:provider], shipment[:size]
+          shipment.provider, shipment.size
         ]
       ]