Implement surcharges

Author: monorkin

README.md

@@ -9,12 +9,21 @@ Croatia is a gem that contains various utilities for performing Croatia-specific
   - [x] Parsing
   - [x] Generation
 - [ ] Invoices
+  - [ ] Line items
+    - [x] Discounts
+      - [x] Percentage
+      - [x] Total
+    - [x] Taxes
+      - [x] Types
+      - [x] Categories
+    - [ ] Surcharges _(Naknade)_
+    - [ ] Margins _(Marza)_
 - [x] Payment barcodes
   - [x] HUB3 standard 2D barcode generation
 - [ ] Fiscalization v2.3 _(Fiskalizacija)_
   - [x] Issuer protection code generation _(ZKI)_
-  - [ ] Invoices _(racuni)_
   - [x] Reverse _(storno)_
+  - [ ] Invoices _(racuni)_
   - [ ] Supporting documents _(prateci dokumenti - otpremnice, radni nalozi, ponude, ugovori, ...)_
   - [ ] Payment method change
   - [x] Verification QR code generation

lib/croatia/invoice/line_item.rb

@@ -6,7 +6,7 @@
 class Croatia::Invoice::LineItem
   include Croatia::Enum
 
-  attr_accessor :description, :unit, :taxes
+  attr_accessor :description, :unit, :taxes, :surcharges
   attr_reader :quantity, :unit_price, :discount_rate
 
   def initialize(**options)
@@ -15,6 +15,7 @@ def initialize(**options)
     self.unit = options[:unit]
     self.unit_price = options.fetch(:unit_price, 0.0)
     self.taxes = options.fetch(:taxes, {})
+    self.surcharges = options.fetch(:surcharges, {})
   end
 
   def quantity=(value)
@@ -102,8 +103,12 @@ def tax
     tax_breakdown.sum { |breakdown| breakdown[:tax] }
   end
 
+  def surcharge
+    surcharges.values.sum(&:amount).round(2, BigDecimal::ROUND_HALF_UP)
+  end
+
   def total
-    (subtotal + tax).round(2, BigDecimal::ROUND_HALF_UP)
+    (subtotal + tax + surcharge).round(2, BigDecimal::ROUND_HALF_UP)
   end
 
   def add_tax(tax = nil, **options, &block)
@@ -132,4 +137,23 @@ def vat_exempt?
   def outside_vat_scope?
     !!taxes[:value_added_tax]&.outside_scope?
   end
+
+  def add_surcharge(surcharge = nil, **options, &block)
+    if surcharge.nil?
+      surcharge = Croatia::Invoice::Surcharge.new(**options)
+    end
+
+    surcharge.tap(&block) if block_given?
+
+    surcharges[surcharge.name] = surcharge
+    surcharge
+  end
+
+  def remove_surcharge(name)
+    surcharges.delete(name)
+  end
+
+  def clear_surcharges
+    surcharges.clear
+  end
 end

lib/croatia/invoice/surcharge.rb

@@ -0,0 +1,31 @@
+# frozen_string_literal: true
+
+require "bigdecimal"
+require "bigdecimal/util"
+
+class Croatia::Invoice::Surcharge
+  include Croatia::Enum
+
+  attr_reader :name, :amount
+
+  def initialize(name:, amount:)
+    self.name = name
+    self.amount = amount
+  end
+
+  def name=(value)
+    if value.nil?
+      raise ArgumentError, "Name cannot be nil"
+    end
+
+    @name = value.to_s.strip
+  end
+
+  def amount=(value)
+    if value.nil?
+      raise ArgumentError, "Amount cannot be nil"
+    end
+
+    @amount = value.to_d
+  end
+end