WIP: Blacklight::PresenterFactory

app/presenters/blacklight/presenter_factory.rb

@@ -0,0 +1,37 @@
+module Blacklight
+  class PresenterFactory
+    attr_reader :config, :action
+
+    def initialize(config, action=nil)
+      @config = config
+      @action = action
+    end
+
+    def build
+      case action
+      when nil
+        default_presenter_class	
+      when 'show', 'citation'
+        show_presenter_class
+      when 'index'
+        index_presenter_class
+      else
+        raise RuntimeError, "Unable to determine presenter type for #{action}"
+      end
+    end
+
+    private
+
+      def default_presenter_class
+        Blacklight::DocumentPresenter
+      end
+
+      def show_presenter_class
+        config.show.document_presenter_class
+      end
+
+      def index_presenter_class
+        config.index.document_presenter_class
+      end      
+  end
+end

spec/presenters/presenter_factory_spec.rb

@@ -0,0 +1,38 @@
+require 'spec_helper'
+
+describe Blacklight::PresenterFactory do
+  let(:config) { Blacklight::Configuration.new }
+  let(:custom_presenter_class) { double }
+  subject { described_class.new(config, action).build }
+
+  context "by default" do
+    let(:action) { nil }
+    it { is_expected.to eq(Blacklight::DocumentPresenter) }
+  end
+
+  context "with an index action" do
+    let(:action) { 'index' }
+    it { is_expected.to eq(Blacklight::IndexPresenter) }
+    context "when using the value defined in the blacklight configuration" do
+      before { config.index.document_presenter_class = custom_presenter_class }
+  	  it { is_expected.to eq(custom_presenter_class) }
+    end
+  end
+
+  context "with a show action" do
+    let(:action) { 'show' }
+    it { is_expected.to eq(Blacklight::ShowPresenter) }
+    context "when using the value defined in the blacklight configuration" do
+      before { config.show.document_presenter_class = custom_presenter_class }
+      it { is_expected.to eq(custom_presenter_class) }
+    end
+  end
+
+  context "with an unrecognized action" do
+    let(:action) { 'foo' }
+    it "raises an error" do
+      expect{ subject }.to raise_error(RuntimeError)
+    end
+  end
+
+end