Implement key data model

- Added classes for Person, Gender, Family, FamilyTree
- Replaced FamilyTreeManager with FamilyTree
- Add FamilyFactory for seeding the initial FamilyTree for King Arthur and Queen Margaret
- Added a RelationshipManager for linking spouses correctly
- Refactored ActionFileExecutor for readability
- More test coverage

1 files changed, 21 insertions, 0 deletions

diff --git a/lib/relationship_manager.rb b/lib/relationship_manager.rb
new file mode 100644
index 0000000..4b6a4a2
--- /dev/null
+++ b/lib/relationship_manager.rb
@@ -0,0 +1,21 @@
+# frozen_string_literal: true
+
+require 'singleton'
+
+class RelationshipManager
+  include Singleton
+  def link_spouses(person1, person2)
+    # Check if either person is already linked to someone else
+    if person1.spouse != NilPerson.new && person1.spouse != person2
+      raise "Cannot link #{person1.name} and #{person2.name}: #{person1.name} is already linked to #{person1.spouse.name}."
+    end
+
+    if person2.spouse != NilPerson.new && person2.spouse != person1
+      raise "Cannot link #{person1.name} and #{person2.name}: #{person2.name} is already linked to #{person2.spouse.name}."
+    end
+
+    # Link the spouses
+    person1.spouse = person2
+    person2.spouse = person1 unless person2.is_a?(NilPerson)
+  end
+end