Add Composer of Spring

lib/magic/card_list.rb

@@ -32,6 +32,10 @@ def permanents
       by_any_type(T::Artifact, T::Creature, T::Enchantment, T::Land, T::Planeswalker)
     end
 
+    def enchantments
+      select(&:enchantment?)
+    end
+
     def dead
       select(&:dead?)
     end

lib/magic/cards/composer_of_spring.rb

@@ -0,0 +1,56 @@
+module Magic
+  module Cards
+    ComposerOfSpring = Creature("Composer of Spring") do
+      cost "{1}{G}"
+      creature_type "Satyr Bard"
+      power 2
+      toughness 3
+    end
+
+    class ComposerOfSpring < Creature
+      class EntersTrigger < TriggeredAbility::EnterTheBattlefield
+        def should_perform?
+          enchantment? && under_your_control?
+        end
+
+
+        def call
+          choice = if battlefield.controlled_by(controller).enchantments.count > 6
+            LandOrCreatureChoice
+          else
+            LandChoice
+          end
+
+          game.add_choice(choice.new(actor: actor))
+        end
+      end
+
+      class LandChoice < Magic::Choice::May
+        def choices
+          controller.hand.lands
+        end
+
+        def resolve!(target:)
+          target.resolve!(enters_tapped: true)
+        end
+      end
+
+      class LandOrCreatureChoice < Magic::Choice::May
+        def choices
+          controller.hand.lands + controller.hand.creatures
+        end
+
+        def resolve!(target:)
+          target.resolve!(enters_tapped: true)
+        end
+      end
+
+      def event_handlers
+        {
+          Events::EnteredTheBattlefield => EntersTrigger
+        }
+      end
+
+    end
+  end
+end

lib/magic/zone.rb

@@ -51,5 +51,9 @@ def battlefield?
     def exile?
       false
     end
+
+    def lands
+      cards.lands
+    end
   end
 end

spec/cards/composer_of_spring_spec.rb

@@ -0,0 +1,63 @@
+require "spec_helper"
+
+RSpec.describe Magic::Cards::ComposerOfSpring do
+  include_context "two player game"
+
+  subject { ResolvePermanent("Composer of Spring") }
+
+  context "when an enchantment enters under your control" do
+    it "may put a land from your hand into play tapped" do
+      subject
+
+      p1.add_mana(white: 3)
+      p1.cast(card: Card("Nine Lives")) do
+        _1.pay_mana(generic: { white: 1 }, white: 2)
+      end
+
+      game.tick!
+
+      expect(game.choices.last).to be_a(Magic::Cards::ComposerOfSpring::LandChoice)
+      expect(game.choices.last.choices).to eq(p1.hand.lands)
+
+      chosen_land = p1.hand.lands.first
+
+      game.resolve_choice!(target: chosen_land)
+
+      game.tick!
+
+      expect(game.battlefield.by_name("Forest").count).to eq(1)
+    end
+
+    context "when there are 6 or more enchantments" do
+      before do
+        6.times { ResolvePermanent("Nine Lives", owner: p1) }
+
+        p1.hand.add(Card("Wood Elves"))
+      end
+
+      it "may put a land or creature from your hand into play tapped" do
+        subject
+
+        p1.add_mana(white: 3)
+        p1.cast(card: Card("Nine Lives")) do
+          _1.pay_mana(generic: { white: 1 }, white: 2)
+        end
+
+        game.tick!
+
+        expect(game.choices.last).to be_a(Magic::Cards::ComposerOfSpring::LandOrCreatureChoice)
+        expect(game.choices.last.choices).to eq(p1.hand.lands + p1.hand.creatures)
+
+        chosen_creature = p1.hand.creatures.first
+
+        game.resolve_choice!(target: chosen_creature)
+
+        game.tick!
+
+        expect(game.battlefield.by_name(chosen_creature.name).count).to eq(1)
+      end
+
+
+    end
+  end
+end