Add tax_references, its controller and some basic pages for viewing ref data about taxes.

app/assets/stylesheets/tax_references.scss

@@ -0,0 +1,3 @@
+// Place all the styles related to the TaxReferences controller here.
+// They will automatically be included in application.css.
+// You can use Sass (SCSS) here: https://sass-lang.com/

app/controllers/tax_references_controller.rb

@@ -0,0 +1,10 @@
+class TaxReferencesController < ApplicationController
+  def index
+    @tax_references = TaxReference.all
+  end
+
+  def show
+    @tax_references = TaxReference.all
+    @tax_reference = TaxReference.find_by(year: params[:year])
+  end
+end

app/helpers/tax_references_helper.rb

@@ -0,0 +1,2 @@
+module TaxReferencesHelper
+end

app/models/tax_reference.rb

@@ -0,0 +1,17 @@
+class TaxReference < ApplicationRecord
+  validates :year, uniqueness: true
+  MAX_MONTHLY_HOURS = 172
+
+  def worker_contribution(number_of_hours)
+    return self.hourly_wage * number_of_hours * self.worker_percentage / 100
+  end
+
+  def employer_contribution(number_of_hours)
+    return self.hourly_wage * number_of_hours * self.employer_percentage / 100
+  end
+
+  def total_contribution(number_of_hours)
+    return self.employer_contribution(number_of_hours) +
+        self.worker_contribution(number_of_hours)
+  end
+end

app/views/layouts/_top_navigation.html.erb

@@ -7,11 +7,11 @@
 
   <div class="collapse navbar-collapse" id="navbarSupportedContent">
     <ul class="navbar-nav mr-auto">
-      <li class="nav-item active">
-        <a class="nav-link" href="#">Home <span class="sr-only">(current)</span></a>
+      <li class="nav-item">
+        <%= link_to(t('Home'), root_path, class: 'nav-link') %>
       </li>
       <li class="nav-item">
-        <a class="nav-link" href="#">Link</a>
+        <%= link_to(t('Tax References Tables'), tax_references_path, class: 'nav-link') %>
       </li>
       <li class="nav-item dropdown">
         <a class="nav-link dropdown-toggle" href="#" id="navbarDropdown" role="button" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false">

app/views/tax_references/_top_list.html.erb

@@ -0,0 +1,13 @@
+<ul class="nav nav-tabs" role="tablist">
+  <% tax_references.each do |tax_ref| %>
+    <li class="nav-item">
+      <% item_class = 'nav-link' %>
+      <% if not @tax_reference.nil? and tax_ref.year == @tax_reference.year %>
+        <% item_class.concat(' active') %>
+      <% end %>
+
+      <%= link_to tax_ref.year, {controller: 'tax_references', action: :show, year: tax_ref.year},
+                  class: item_class %>
+    </li>
+  <% end %>
+</ul>

app/views/tax_references/index.html.erb

@@ -0,0 +1 @@
+<%= render 'top_list', tax_references: @tax_references %>

app/views/tax_references/show.html.erb

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+<%= render 'top_list', tax_references: @tax_references %>
+
+<p><%= @tax_reference.year %></p>
+<p><%= @tax_reference.hourly_wage %></p>
+<p><%= number_to_percentage(@tax_reference.worker_percentage, precision: 2) %></p>
+<p><%= number_to_percentage(@tax_reference.employer_percentage, precision: 2) %></p>
+
+<table>
+  <thead>
+  <tr>
+    <th><%= t('Number of Hours') %></th>
+    <th><%= t('Employer (extra)') %></th>
+    <th><%= t('Worker (discount)') %></th>
+    <th><%= t('Total contribution') %></th>
+  </tr>
+  </thead>
+  <tbody>
+  <% hourly_contribution = @tax_reference.hourly_wage / 100 %>
+  <% (@tax_reference.min_monthly_hours..TaxReference::MAX_MONTHLY_HOURS).each do |n_hours| %>
+    <tr>
+      <td><%= n_hours %></td>
+      <td><%= number_to_currency(@tax_reference.employer_contribution(n_hours), locale: :pt) %></td>
+      <td><%= number_to_currency(@tax_reference.worker_contribution(n_hours), locale: :pt) %></td>
+      <td><%= number_to_currency(@tax_reference.total_contribution(n_hours), locale: :pt) %></td>
+    </tr>
+  <% end %>
+  </tbody>
+</table>