From 7bd84590e5bd111ea598c6142513ee0ddb0474c6 Mon Sep 17 00:00:00 2001
From: lukaszreszke <lukaszreszke93@gmail.com>
Date: Thu, 14 Nov 2024 14:26:08 +0100
Subject: [PATCH] Process manager

---
 rails_application/app/services/send_email.rb | 37 ++++++++++++++++++++
 rails_application/lib/configuration.rb       |  5 +++
 2 files changed, 42 insertions(+)
 create mode 100644 rails_application/app/services/send_email.rb

diff --git a/rails_application/app/services/send_email.rb b/rails_application/app/services/send_email.rb
new file mode 100644
index 00000000..b6564a0b
--- /dev/null
+++ b/rails_application/app/services/send_email.rb
@@ -0,0 +1,37 @@
+# frozen_string_literal: true
+
+class SendEmail
+  def call(event)
+    event_store.link(event.event_id, stream_name: "Sales$#{order_id(event)}")
+
+    state = {}
+
+    event_store.read.stream("Sales$#{order_id(event)}").each do |event_in_stream|
+      case event_in_stream
+      when Ordering::OrderPaid
+        state[:order_paid] = true
+      when Invoicing::InvoiceGenerated
+        state[:invoice_generated] = true
+      end
+    end
+
+    if state[:order_paid] && state[:invoice_generated]
+      Rails.configuration.email_client.send_email(order_id(event))
+    end
+  end
+
+  private
+
+  def order_id(event)
+    case event
+    when Ordering::OrderPaid
+      event.data[:id]
+    when Invoicing::InvoiceGenerated
+      event.data[:order_id]
+    end
+  end
+
+  def event_store
+    Rails.configuration.event_store
+  end
+end
diff --git a/rails_application/lib/configuration.rb b/rails_application/lib/configuration.rb
index 07946910..ece0a1cd 100644
--- a/rails_application/lib/configuration.rb
+++ b/rails_application/lib/configuration.rb
@@ -21,6 +21,11 @@ def call(event_store, command_bus)
       Inventory::UpdateProductCatalog,
       to: [Inventory::StockLevelIncreased, Inventory::StockLevelDecreased]
     )
+
+    event_store.subscribe(
+      SendEmail,
+      to: [Ordering::OrderPaid, Invoicing::InvoiceGenerated]
+    )
   end
 
   def self.available_vat_rates