From 633bcdd3d62cd86aae0f3861d5231833bfb56667 Mon Sep 17 00:00:00 2001
From: Ralph Soika <ralph.soika@imixs.com>
Date: Sat, 30 Nov 2024 18:28:58 +0100
Subject: [PATCH] agl debitor metric service

---
 .../MetricDebitorService.java                 | 38 +++++++++++++++----
 1 file changed, 31 insertions(+), 7 deletions(-)

diff --git a/office-alexander-logistics-app/src/main/java/com/alexanderlogistics/MetricDebitorService.java b/office-alexander-logistics-app/src/main/java/com/alexanderlogistics/MetricDebitorService.java
index f617359..f8de301 100644
--- a/office-alexander-logistics-app/src/main/java/com/alexanderlogistics/MetricDebitorService.java
+++ b/office-alexander-logistics-app/src/main/java/com/alexanderlogistics/MetricDebitorService.java
@@ -18,13 +18,22 @@ import org.imixs.workflow.exceptions.QueryException;
 import jakarta.annotation.security.DeclareRoles;
 import jakarta.annotation.security.RolesAllowed;
 import jakarta.annotation.security.RunAs;
+import jakarta.ejb.TransactionAttribute;
+import jakarta.ejb.TransactionAttributeType;
 import jakarta.enterprise.context.ApplicationScoped;
 import jakarta.enterprise.event.Observes;
 import jakarta.inject.Inject;
 
 /**
- * Dieser Service reagiert auch ProcessingEvents und speichert/aktualisert die
+ * Dieser Service reagiert auch ProcessingEvents und speichert/aktualisiert die
  * zugehörige Debitoren Metric Entity.
+ * <p>
+ * Der Service liest in einem AFTER_PROCESS Event den alten invoice.saldo aus.
+ * Hierzu wird die Rechnung in einer neuen Transaktion geladen was einem
+ * 'Dirty-Read' entspricht. Dadurch kennt die Methode den letzten saldo der
+ * Rechnung. Hat sich nun der aktuelle Saldo geändert, aktualisiert der Serivce
+ * die entsprechende Metric.
+ * 
  * 
  */
 @DeclareRoles({ "org.imixs.ACCESSLEVEL.NOACCESS", "org.imixs.ACCESSLEVEL.READERACCESS",
@@ -42,7 +51,6 @@ public class MetricDebitorService {
 
     public static final String METRIC_INVOICES = "invoices";
     public static final String TYPE_METRIC_DEBITOR = "metric.debitor";
-    public static final String ITEM_LAST_METRIC = "metric.saldo";
     public static final String ITEM_SALDO = "invoice.saldo";
 
     @Inject
@@ -68,7 +76,8 @@ public class MetricDebitorService {
 
         // verify if saldo has changed.....
         double invoiceSaldo = invoice.getItemValueDouble(ITEM_SALDO);
-        if (invoiceSaldo == invoice.getItemValueDouble(ITEM_LAST_METRIC)) {
+        double lastInvoiceSaldo = readDirtySaldo(invoice.getUniqueID());
+        if (invoiceSaldo == lastInvoiceSaldo) {
             // no change - no metric update!
             return;
         }
@@ -82,9 +91,9 @@ public class MetricDebitorService {
 
             // Saldo-Berechnung wie bisher
             debitorSaldo = metric.getItemValueDouble(ITEM_SALDO);
-            if (invoice.hasItem(ITEM_LAST_METRIC)) {
-                debitorSaldo = debitorSaldo - invoice.getItemValueDouble(ITEM_LAST_METRIC);
-            }
+            debitorSaldo = debitorSaldo - lastInvoiceSaldo;
+
+            // update debitor saldo
             debitorSaldo = InvoiceUtil.round(debitorSaldo + invoiceSaldo);
 
             // Speichern in der Datenbank
@@ -100,6 +109,21 @@ public class MetricDebitorService {
         }
     }
 
+    /**
+     * This helper method reads the 'dirty' saldo in a new transaction. This is used
+     * for calculating the new total saldo
+     * 
+     * @param uniqueid
+     */
+    @TransactionAttribute(value = TransactionAttributeType.REQUIRES_NEW)
+    public double readDirtySaldo(String uniqueid) {
+        double result = 0;
+        ItemCollection dirtyInvoice = documentService.load(uniqueid);
+        result = dirtyInvoice.getItemValueDouble(ITEM_SALDO);
+        logger.info("---Dirty last Saldo was : " + result);
+        return result;
+    }
+
     /**
      * This method loads a metric entity. If no metric entity exits, the method
      * creates a new one.
@@ -142,7 +166,7 @@ public class MetricDebitorService {
      * verwendet.
      * 
      */
-    public void initMetric(ItemCollection metric) {
+    protected void initMetric(ItemCollection metric) {
         String dbtrNumber = metric.getItemValueString("dbtr.number");
         double saldo = metric.getItemValueDouble(ITEM_SALDO);