Improve dialog shown when system is already resgistered

* Disable the "Register Again" button if the system cannot be
  re-registered.
* Adapt the help text display according the status of available actions.
  I.e, does not state "You can re-register" when the system cannot be
  re-registered.
* Add unit test.

src/lib/registration/clients/inst_scc.rb

@@ -230,13 +230,16 @@ def registration_check
       return :cancel if init_registration == :cancel
 
       extensions_enabled = true
+
       success = Registration::ConnectHelpers.catch_registration_errors do
         extensions_enabled = !Registration::Addon.find_all(@registration).empty?
       end
+
       return :abort unless success
 
       ::Registration::UI::RegisteredSystemDialog.run(
-        extensions_enabled: extensions_enabled
+        extensions:   extensions_enabled,
+        registration: ::Registration::Registration.allowed?
       )
     end
 

src/lib/registration/ui/registered_system_dialog.rb

@@ -17,46 +17,46 @@ class RegisteredSystemDialog
       Yast.import "Label"
       Yast.import "UI"
 
-      # displays and run the status dialog for an already registered system
+      # Displays and run the status dialog for an already registered system
+      #
+      # @param extensions [Boolean] Whether "Select extensions" button shoudl be enabled
+      # @param registration [Boolean] Whether the "Register Again" button should be enabled
       #
-      # @param extensions_enabled [Boolean] select extension button enabled
       # @return [Symbol] user input
-      def self.run(extensions_enabled: true)
-        dialog = RegisteredSystemDialog.new
-        dialog.run(extensions_enabled: extensions_enabled)
+      def self.run(extensions: true, registration: true)
+        RegisteredSystemDialog.new(extensions: extensions, registration: registration).run
       end
 
-      # the constructor
-      def initialize
+      # Constructor
+      #
+      # @param extensions [Boolean] Whether "Select extensions" button shoudl be enabled
+      # @param registration [Boolean] Whether the "Register Again" button should be enabled
+      def initialize(extensions: true, registration: true)
         textdomain "registration"
+
+        @extensions = extensions
+        @registration = registration
       end
 
-      # display and run the dialog
+      # Display and run the dialog
       #
       # @param extensions_enabled [Boolean] select extension button enabled
       # @return [Symbol] user input
-      def run(extensions_enabled: true)
+      def run
         Wizard.SetContents(
           # dialog title
           _("Registration"),
           dialog_content,
-          # help text
-          _("<p>The system is already registered.</p>") +
-            _("<p>You can re-register it again or you can register additional "\
-              "extension or modules to enhance the functionality of the system.</p>") +
-            _("<p>If you want to deregister your system you need to log "\
-              "into the SUSE Customer Center and remove the system manually there.</p>"),
+          help_text,
           true,
           true
         )
 
-        Yast::UI.ChangeWidget(Id(:extensions), :Enabled, extensions_enabled)
+        Yast::UI.ChangeWidget(Id(:extensions), :Enabled, extensions)
+        Yast::UI.ChangeWidget(Id(:register), :Enabled, registration)
         Wizard.SetNextButton(:next, Label.FinishButton) if Mode.normal
 
-        continue_buttons = [:next, :back, :cancel, :abort, :register, :extensions]
-
-        ret = nil
-        ret = Yast::UI.UserInput until continue_buttons.include?(ret)
+        ret = Yast::UI.UserInput until available_actions.include?(ret)
 
         Wizard.RestoreNextButton
 
@@ -65,19 +65,56 @@ def run(extensions_enabled: true)
 
     private
 
-      # the main dialog content
+      attr_reader :extensions, :registration
+
+      # Available dialog actions
+      #
+      # @returns [Symbol]
+      def available_actions
+        [:next, :back, :cancel, :abort, :register, :extensions]
+      end
+
+      # The dialog content
+      #
       # @return [Yast::Term] UI term
       def dialog_content
         VBox(
           Heading(_("The system is already registered.")),
           VSpacing(2),
-          # button label
           PushButton(Id(:extensions), _("Select Extensions")),
           VSpacing(1),
-          # button label
           PushButton(Id(:register), _("Register Again"))
         )
       end
+
+      # The dialog's help text
+      #
+      # @return [String]
+      def help_text
+        text = [_("<p>The system is already registered.</p>")]
+        text << actions_help
+        text << _("<p>If you want to deregister your system you need to log "\
+                  "into the SUSE Customer Center and remove the system manually there.</p>")
+        text.join
+      end
+
+      # The help text for enabled actions
+      #
+      # @return [String]
+      def actions_help
+        if extensions && registration
+          _("<p>You can re-register it again or register additional "\
+            "extension or modules to enhance the functionality of the system.</p>")
+        elsif extensions
+          _("<p>You can register additional extension or modules "\
+            "to enhance the functionality of the system.</p>")
+        elsif registration
+          _("<p>You can re-register it again.")
+        else
+          _("<p>At this moment, you can neither re-register it again " \
+            "nor register additional extensions</p>")
+        end
+      end
     end
   end
 end

test/registration/ui/registered_system_dialog_test.rb

@@ -0,0 +1,154 @@
+#!/usr/bin/env rspec
+# ------------------------------------------------------------------------------
+# Copyright (c) 2018 SUSE LLC, All Rights Reserved.
+#
+# This program is free software; you can redistribute it and/or modify it under
+# the terms of version 2 of the GNU General Public License as published by the
+# Free Software Foundation.
+#
+# This program is distributed in the hope that it will be useful, but WITHOUT
+# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
+# FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
+# ------------------------------------------------------------------------------
+
+require_relative "../../spec_helper"
+require "registration/ui/registered_system_dialog"
+
+describe Registration::UI::RegisteredSystemDialog do
+  include Yast::UIShortcuts
+
+  subject(:dialog) { described_class.new(extensions: extensions, registration: registration) }
+
+  let(:extensions) { true }
+  let(:registration) { true }
+
+  describe ".run" do
+    let(:dialog) { double(Registration::UI::RegisteredSystemDialog, run: true) }
+
+    before do
+      allow(described_class).to receive(:new).and_return(dialog)
+    end
+
+    it "creates an instance of the dialog" do
+      expect(described_class).to receive(:new)
+
+      described_class.run
+    end
+
+    it "runs the dialog" do
+      expect(dialog).to receive(:run)
+
+      described_class.run
+    end
+  end
+
+  describe "#run" do
+    let(:mode) { "installation" }
+    let(:user_input) { :cancel }
+
+    before do
+      allow(Yast::Wizard).to receive(:SetContents)
+      allow(Yast::Wizard).to receive(:SetNextButton)
+      allow(Yast::Wizard).to receive(:RestoreNextButton)
+
+      allow(Yast::Mode).to receive(:mode).and_return(mode)
+
+      allow(Yast::UI).to receive(:ChangeWidget)
+      allow(Yast::UI).to receive(:UserInput).and_return(user_input)
+    end
+
+    it "returns the user input" do
+      expect(subject.run).to eq(:cancel)
+    end
+
+    it "does not change the next button label" do
+      expect(Yast::Wizard).to_not receive(:SetNextButton)
+    end
+
+    it "keeps 'Select Extensions' button enabled" do
+      expect(Yast::UI).to_not receive(:ChangeWidget).with(Id(:extensions), :Enabled, false)
+
+      subject.run
+    end
+
+    it "includes help for 'Select Extensions' button" do
+      expect(Yast::Wizard).to receive(:SetContents).with(
+        anything,
+        anything,
+        /register additional extension/,
+        any_args
+      )
+
+      subject.run
+    end
+
+    it "keeps 'Register Again' button enabled" do
+      expect(Yast::UI).to_not receive(:ChangeWidget).with(Id(:register), :Enabled, false)
+
+      subject.run
+    end
+
+    it "includes help for 'Register Again' button" do
+      expect(Yast::Wizard).to receive(:SetContents).with(
+        anything,
+        anything,
+        /re-register it again/,
+        any_args
+      )
+
+      subject.run
+    end
+
+    context "when running in normal mode" do
+      let(:mode) { "normal" }
+
+      it "changes the next button label" do
+        expect(Yast::Wizard).to receive(:SetNextButton)
+
+        subject.run
+      end
+    end
+
+    context "when extensions are not enabled" do
+      let(:extensions) { false }
+
+      it "disables 'Select Extensions' button" do
+        expect(Yast::UI).to receive(:ChangeWidget).with(Id(:extensions), :Enabled, false)
+
+        subject.run
+      end
+
+      it "does not include help for it" do
+        expect(Yast::Wizard).to_not receive(:SetContents).with(
+          anything,
+          anything,
+          /register additional extension/,
+          any_args
+        )
+
+        subject.run
+      end
+    end
+
+    context "when register is not enabled" do
+      let(:registration) { false }
+
+      it "disables 'Register Again' button" do
+        expect(Yast::UI).to receive(:ChangeWidget).with(Id(:register), :Enabled, false)
+
+        subject.run
+      end
+
+      it "does not include help for it" do
+        expect(Yast::Wizard).to_not receive(:SetContents).with(
+          anything,
+          anything,
+          /re-register it again/,
+          any_args
+        )
+
+        subject.run
+      end
+    end
+  end
+end