Refactor index

lib/sales_engine.rb

@@ -34,9 +34,9 @@ def self.load_directory(directory, options = {})
     if options[:index]
       Thread.new do 
         t = Time.now
-        puts "indexing everything!"
         SalesEngine::Persistence.instance.index(:id)
-        puts "Indexing completed in #{Time.now - t} seconds!"
+        SalesEngine::Persistence.instance.insert_index(:merchant_id, SalesEngine::Invoice)
+        puts "\nIndexing completed in #{Time.now - t} seconds!"
       end
     end
   end

lib/sales_engine/invoice.rb

@@ -25,5 +25,9 @@ def customer
     def merchant
       @merchant ||= Merchant.find(@merchant_id)
     end
+
+    def revenue
+      InvoiceItem.find_all_by_invoice_id(id).map(&:revenue).inject(:+)
+    end
   end
 end

lib/sales_engine/invoice_item.rb

@@ -16,6 +16,10 @@ def initialize(attributes)
       validate_attributes
     end
 
+    def revenue
+      unit_price * quantity
+    end
+
     private
 
     def validate_attributes

lib/sales_engine/merchant.rb

@@ -27,9 +27,23 @@ def invoices
       @invoices ||= Invoice.find_all_by_merchant_id(self.id)
     end
 
-    def revenue(date=nil)
-
+    def revenue
+      @revenue ||= Invoice.find_all_by_merchant_id(id).map(&:revenue).inject(:+)
     end
 
+    def self.revenue(date=nil)
+      Invoice.find_all_by_created_at_date(date).map(&:revenue).inject(:+)      
+    end
+
+    def self.most_revenue(n)
+      merchants_and_revenues = []
+
+      merchants = Merchant.find_all
+      merchants.each do |merchant|
+        merchants_and_revenues.push [merchant.revenue, merchant]
+      end
+
+      # merchants_and_revenues.sort_by { |rev_mer| rev_mer[0] }.map(&:last)[0..n]
+    end
   end
 end

lib/sales_engine/model.rb

@@ -49,6 +49,10 @@ def self.included(target)
       target.extend ClassMethods
     end
 
+    def created_at_date
+      @created_at.to_date
+    end
+
     module ClassMethods
       def find(id)
         find_by_id(id)
@@ -94,7 +98,7 @@ def find_by(attribute, *values)
         indices = SalesEngine::Persistence.instance.fetch_indices(self)
 
         unless indices.empty?
-          model = indices[attribute][value] if indices[attribute]
+          model = indices[attribute][value].first if indices[attribute]
         end
 
         unless model
@@ -109,8 +113,16 @@ def find_all_by(attribute, *values)
         attribute = attribute.to_sym
         value = values[0]
 
-        models = SalesEngine::Persistence.instance.fetch(self)
-        model = models.find_all { |m| m.send(attribute) == value }
+        indices = SalesEngine::Persistence.instance.fetch_indices(self)
+
+        unless indices.empty?
+          models = indices[attribute][value] if indices[attribute]
+        end
+
+        unless models
+          models = SalesEngine::Persistence.instance.fetch(self)
+          model = models.find_all { |m| m.send(attribute) == value }
+        end
       end
     end
   end

lib/sales_engine/persistence.rb

@@ -17,6 +17,7 @@ def persist(model)
       else
         @data[name] = [model]
       end
+
       true
     end
 
@@ -59,6 +60,24 @@ def insert_index(attribute, class_name)
       @indices[class_name][attribute] = result
     end
 
+    def index_attribute_by_class(attribute, class_name)
+      result = {}
+
+      data = @data[class_name]
+
+      data.each do |model|
+        value = model.send(attribute)
+
+        if result[value]
+          result[value].push model
+        else
+          result[value] = [model]
+        end
+      end
+
+      result
+    end
+
     def index_all
       @data.keys.each do |class_name|
         datum = @data[class_name]
@@ -84,20 +103,5 @@ def dump_indices
     def import(data)
       @data = data
     end
-
-    private
-
-    def index_attribute_by_class(attribute, class_name)
-      result = {}
-
-      data = @data[class_name]
-
-      data.each do |model|
-        value = model.send(attribute)
-        result[value] = model
-      end
-
-      result
-    end
   end
 end

spec/merchant_spec.rb

@@ -3,6 +3,8 @@
 describe SalesEngine::Merchant do
   let(:merchant) { Fabricate(:merchant) }
 
+  before(:all) { SalesEngine.startup('data/evaluation') }
+
   it 'creates a merchant with valid attributes' do
     merchant.nil?.should be_false
   end
@@ -100,4 +102,22 @@
       end
     end
   end
+
+  context "Business Intelligence" do
+    describe ".revenue" do
+      it "returns all revenue for a given date" do
+        date = Date.parse "Tue, 20 Mar 2012"
+
+        SalesEngine::Merchant.revenue(date).to_f.should be_within(0.001).of(263902466.0)
+      end
+    end
+
+    describe ".most_revenue" do
+      it "returns the top n revenue-earners" do
+        most = SalesEngine::Merchant.most_revenue(3)
+        most.first.name.should == "Dicki-Bednar"
+        most.last.name.should  == "Okuneva, Prohaska and Rolfson"
+      end
+    end
+  end
 end

spec/persistence_spec.rb

@@ -45,7 +45,7 @@ def initialize(attributes)
       attribute = :id
       persistence.index(attribute)
       indices = persistence.dump_indices
-      indices[model.class][attribute][model.id].should be model
+      indices[model.class][attribute][model.id].first.should be model
     end
   end
 

spec/sales_engine_spec.rb

@@ -37,8 +37,8 @@
     end
 
     it "creates models" do
-      #SalesEngine.load_directory(directory)
-      #SalesEngine::Persistence.instance.dump_data.should_not be_empty
+      SalesEngine.load_directory(directory)
+      SalesEngine::Persistence.instance.dump_data.should_not be_empty
     end
   end
 end