Add phase banner to the app

We want to add a phase banner that will indicate to our users that this
app is in Beta. The banner title is dynamic based on the environment we
are in and both claims and placements can control the content of it.

app/assets/stylesheets/application.sass.scss

@@ -3,3 +3,5 @@ $govuk-new-link-styles: true;
 $govuk-assets-path: "";
 
 @import "govuk-frontend/dist/govuk/all";
+
+@import "components/all";

app/assets/stylesheets/components/_all.scss

@@ -0,0 +1 @@
+@import "page_banner";

app/assets/stylesheets/components/_page_banner.scss

@@ -0,0 +1,22 @@
+.app-phase-banner .govuk-tag {
+  color: govuk-colour("white");
+  text-transform: uppercase;
+  letter-spacing: 1px;
+  font-weight: 700;
+}
+
+.app-phase-banner__env--development .govuk-tag {
+  background: govuk-colour("dark-grey");
+}
+
+.app-phase-banner__env--qa .govuk-tag {
+  background-color: govuk-colour("orange");
+}
+
+.app-phase-banner__env--staging .govuk-tag {
+  background-color: govuk-colour("red");
+}
+
+.app-phase-banner__env--beta .govuk-tag {
+  background: govuk-colour("blue");
+}

app/models/hosting_environment.rb

@@ -0,0 +1,13 @@
+module HostingEnvironment
+  def self.name(current_service)
+    if Rails.env.production?
+      I18n.t(".models.hosting_environment.#{current_service}.name")
+    else
+      Rails.env
+    end
+  end
+
+  def self.banner_description(current_service)
+    I18n.t(".models.hosting_environment.#{current_service}.banner.description")
+  end
+end

app/views/layouts/application.html.erb

@@ -27,6 +27,14 @@
 
     <%= govuk_header(homepage_url: "https://www.gov.uk", service_name: t(".#{current_service}.header.service_name"), service_url: "/") %>
 
+    <div class="app-phase-banner app-phase-banner__env--<%= HostingEnvironment.name(current_service) %>">
+      <div class="govuk-width-container">
+        <%= govuk_phase_banner(tag: { text: HostingEnvironment.name(current_service) }) do %>
+          <%= govuk_link_to HostingEnvironment.banner_description(current_service), request.env["PATH_INFO"], class: "govuk-link--no-visited-state" %>
+        <% end %>
+      </div>
+    </div>
+
     <div class="govuk-width-container">
       <main class="govuk-main-wrapper" id="main-content" role="main">
         <%= yield %>

config/locales/claims/en/models/hosting_environment.yml

@@ -0,0 +1,7 @@
+en:
+  models:
+    hosting_environment:
+      claims:
+        name: beta
+        banner:
+          description: Make a complaint or give feedback

config/locales/placements/en/models/hosting_environment.yml

@@ -0,0 +1,7 @@
+en:
+  models:
+    hosting_environment:
+      placements:
+        name: beta
+        banner:
+          description: Make a complaint or give feedback

spec/models/hosting_environment_spec.rb

@@ -0,0 +1,40 @@
+require "rails_helper"
+
+RSpec.describe HostingEnvironment do
+  describe ".name" do
+    it "returns the name of the hosting environment" do
+      current_service = "claims"
+      expect(described_class.name(current_service)).to eq("test")
+    end
+
+    context "when environment is production" do
+      it "returns the name of the hosting environment for claims" do
+        allow(Rails.env).to receive(:production?).and_return(true)
+        current_service = "claims"
+        expect(described_class.name(current_service)).to eq("beta")
+      end
+
+      it "returns the name of the hosting environment for placements" do
+        allow(Rails.env).to receive(:production?).and_return(true)
+        current_service = "placements"
+        expect(described_class.name(current_service)).to eq("beta")
+      end
+    end
+  end 
+
+  describe ".banner_description" do
+    it "returns the banner description of the hosting environment for claims" do
+      current_service = "claims"
+      expect(described_class.banner_description(current_service)).to eq(
+        "Make a complaint or give feedback"
+      )
+    end
+
+    it "returns the banner description of the hosting environment for placements" do
+      current_service = "placements"
+      expect(described_class.banner_description(current_service)).to eq(
+        "Make a complaint or give feedback"
+      )
+    end
+  end
+end