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QuellCode/CentronERP/tests/backend/Centron.Tests.BL/DataExchange/EDI/SaleInvoices/InvoiceZugferdBalanceMergeTests.cs

@@ -0,0 +1,311 @@
+using System.Linq;
+using Centron.BusinessLogic.DataExchange.EDI;
+using Centron.BusinessLogic.DataExchange.EDI.SaleInvoices;
+using Centron.Data.Entities.Sales.Receipts.Invoices;
+using Centron.Interfaces.DataExchange.BookKeeping;
+using JetBrains.Annotations;
+
+namespace Centron.Tests.BL.DataExchange.EDI.SaleInvoices;
+
+/// <summary>
+/// Tests for the contract-contingent balance merge in <see cref="InvoiceZugferdBL.MergeBalanceCompensationItems"/>.
+/// Service and compensation items share a <see cref="ZugferdExportPositionItem.BalanceID"/>; the merge folds the
+/// compensation amount into the service item and removes the compensation line from the export.
+/// On invoices the service item is positive and the compensation is negative; credit vouchers store the same
+/// pair with inverted signs (Ticket 164110 — without the sign-aware merge the wrong line would be removed
+/// and the position total would no longer match the receipt header).
+/// </summary>
+[TestSubject(typeof(InvoiceZugferdBL))]
+public class InvoiceZugferdBalanceMergeTests
+{
+    private const string BalanceA = "BAL-A";
+    private const string BalanceB = "BAL-B";
+
+    private static ZugferdExportPositionItem Service(string balanceId, decimal netTotal, decimal netUnit, decimal quantity)
+        => new()
+        {
+            BalanceID = balanceId,
+            NetPriceTotalFC = netTotal,
+            NetPrice = netUnit,
+            Quantity = quantity,
+            TaxPriceTotalFC = 0m,
+            ArticleCode = "SERPELISTD",
+            Text = "Servicedienstleistung",
+        };
+
+    private static ZugferdExportPositionItem Compensation(string balanceId, decimal netTotal)
+        => new()
+        {
+            BalanceID = balanceId,
+            NetPriceTotalFC = netTotal,
+            NetPrice = -netTotal,
+            Quantity = 0m,
+            TaxPriceTotalFC = 0m,
+            ArticleCode = "AUSGLEICH",
+            Text = "Ausgleichsartikel für Kontingente",
+        };
+
+    private static ZugferdExportItem ItemWith(params ZugferdExportPositionItem[] positions)
+        => new() { Positions = positions.ToList() };
+
+    [Fact]
+    public void Invoice_FullyCoveredByContingent_ReducesServiceToZeroAndKeepsBasisQuantity()
+    {
+        var service = Service(BalanceA, netTotal: 150m, netUnit: 150m, quantity: 1m);
+        var compensation = Compensation(BalanceA, netTotal: -150m);
+        var export = ItemWith(service, compensation);
+
+        InvoiceZugferdBL.MergeBalanceCompensationItems(export, BookKeepingReceiptKind.Invoice);
+
+        Assert.Single(export.Positions);
+        Assert.Same(service, export.Positions[0]);
+        Assert.Equal(0m, service.NetPriceTotalFC);
+        Assert.Equal(0m, service.Quantity);
+        Assert.Equal(1m, service.BasisQuantity);
+    }
+
+    [Fact]
+    public void Invoice_PartiallyCovered_ReducesServiceProportionally()
+    {
+        var service = Service(BalanceA, netTotal: 150m, netUnit: 150m, quantity: 1m);
+        var compensation = Compensation(BalanceA, netTotal: -90m);
+        var export = ItemWith(service, compensation);
+
+        InvoiceZugferdBL.MergeBalanceCompensationItems(export, BookKeepingReceiptKind.Invoice);
+
+        Assert.Single(export.Positions);
+        Assert.Equal(60m, service.NetPriceTotalFC);
+        Assert.Equal(0.4m, service.Quantity);
+        Assert.Equal(1m, service.BasisQuantity);
+    }
+
+    [Fact]
+    public void CreditVoucher_FullyCoveredByContingent_ReducesServiceToZeroAndKeepsRealServiceLine()
+    {
+        // Credit voucher: signs are inverted compared to the source invoice
+        var service = Service(BalanceA, netTotal: -150m, netUnit: -150m, quantity: 1m);
+        var compensation = Compensation(BalanceA, netTotal: 150m);
+        var export = ItemWith(service, compensation);
+
+        InvoiceZugferdBL.MergeBalanceCompensationItems(export, BookKeepingReceiptKind.CreditVoucher);
+
+        Assert.Single(export.Positions);
+        Assert.Same(service, export.Positions[0]);
+        Assert.Equal("SERPELISTD", export.Positions[0].ArticleCode);
+        Assert.Equal(0m, service.NetPriceTotalFC);
+        Assert.Equal(0m, service.Quantity);
+        Assert.Equal(1m, service.BasisQuantity);
+    }
+
+    [Fact]
+    public void CreditVoucher_PartiallyCovered_ReducesServiceProportionally()
+    {
+        var service = Service(BalanceA, netTotal: -150m, netUnit: -150m, quantity: 1m);
+        var compensation = Compensation(BalanceA, netTotal: 90m);
+        var export = ItemWith(service, compensation);
+
+        InvoiceZugferdBL.MergeBalanceCompensationItems(export, BookKeepingReceiptKind.CreditVoucher);
+
+        Assert.Single(export.Positions);
+        Assert.Equal(-60m, service.NetPriceTotalFC);
+        Assert.Equal(0.4m, service.Quantity);
+        Assert.Equal(1m, service.BasisQuantity);
+    }
+
+    [Fact]
+    public void MultipleBalanceGroups_AreMergedIndependently()
+    {
+        var service1 = Service(BalanceA, netTotal: 150m, netUnit: 150m, quantity: 1m);
+        var compensation1 = Compensation(BalanceA, netTotal: -150m);
+        var service2 = Service(BalanceB, netTotal: 200m, netUnit: 100m, quantity: 2m);
+        var compensation2 = Compensation(BalanceB, netTotal: -100m);
+        var export = ItemWith(service1, compensation1, service2, compensation2);
+
+        InvoiceZugferdBL.MergeBalanceCompensationItems(export, BookKeepingReceiptKind.Invoice);
+
+        Assert.Equal(2, export.Positions.Count);
+        Assert.Equal(0m, service1.NetPriceTotalFC);
+        Assert.Equal(0m, service1.Quantity);
+        Assert.Equal(100m, service2.NetPriceTotalFC);
+        Assert.Equal(1m, service2.Quantity);
+        Assert.DoesNotContain(compensation1, export.Positions);
+        Assert.DoesNotContain(compensation2, export.Positions);
+    }
+
+    [Fact]
+    public void PositionsWithoutBalanceId_AreLeftUntouched()
+    {
+        var standalone = new ZugferdExportPositionItem
+        {
+            BalanceID = null,
+            NetPriceTotalFC = 99m,
+            NetPrice = 99m,
+            Quantity = 1m,
+            ArticleCode = "OTHER",
+        };
+        var export = ItemWith(standalone);
+
+        InvoiceZugferdBL.MergeBalanceCompensationItems(export, BookKeepingReceiptKind.Invoice);
+
+        Assert.Single(export.Positions);
+        Assert.Same(standalone, export.Positions[0]);
+        Assert.Equal(99m, standalone.NetPriceTotalFC);
+        Assert.Equal(1m, standalone.Quantity);
+        Assert.Null(standalone.BasisQuantity);
+    }
+
+    [Fact]
+    public void ResolveServicePeriod_ItemPeriodWinsBeforeReceiptHeadAndFallback()
+    {
+        var receipt = new ReceiptInvoice
+        {
+            ServicePeriodFrom = new System.DateTime(2024, 1, 1),
+            ServicePeriodTo = new System.DateTime(2024, 1, 31),
+        };
+        var item = new ReceiptInvoiceItem
+        {
+            I3D = 10,
+            ServicePeriodFrom = new System.DateTime(2024, 2, 2, 14, 0, 0),
+            ServicePeriodTo = new System.DateTime(2024, 2, 4, 16, 0, 0),
+        };
+        var fallbackCalled = false;
+
+        var result = InvoiceZugferdBL.ResolveServicePeriod(
+            receipt,
+            item,
+            BookKeepingReceiptKind.Invoice,
+            (_, _) =>
+            {
+                fallbackCalled = true;
+                return (new System.DateTime(2024, 3, 1), new System.DateTime(2024, 3, 31));
+            });
+
+        Assert.Equal(new System.DateTime(2024, 2, 2), result.From);
+        Assert.Equal(new System.DateTime(2024, 2, 4), result.To);
+        Assert.False(fallbackCalled);
+    }
+
+    [Fact]
+    public void ResolveServicePeriod_ReceiptHeadWinsBeforeFallback()
+    {
+        var receipt = new ReceiptInvoice
+        {
+            ServicePeriodFrom = new System.DateTime(2024, 1, 1, 9, 0, 0),
+            ServicePeriodTo = new System.DateTime(2024, 1, 31, 18, 0, 0),
+        };
+        var item = new ReceiptInvoiceItem { I3D = 11 };
+        var fallbackCalled = false;
+
+        var result = InvoiceZugferdBL.ResolveServicePeriod(
+            receipt,
+            item,
+            BookKeepingReceiptKind.Invoice,
+            (_, _) =>
+            {
+                fallbackCalled = true;
+                return (new System.DateTime(2024, 3, 1), new System.DateTime(2024, 3, 31));
+            });
+
+        Assert.Equal(new System.DateTime(2024, 1, 1), result.From);
+        Assert.Equal(new System.DateTime(2024, 1, 31), result.To);
+        Assert.False(fallbackCalled);
+    }
+
+    [Fact]
+    public void ResolveServicePeriod_UsesContractFallbackWhenItemAndHeadAreEmpty()
+    {
+        var receipt = new ReceiptInvoice();
+        var item = new ReceiptInvoiceItem { I3D = 12 };
+
+        var result = InvoiceZugferdBL.ResolveServicePeriod(
+            receipt,
+            item,
+            BookKeepingReceiptKind.Invoice,
+            (itemI3D, receiptKind) =>
+            {
+                Assert.Equal(12, itemI3D);
+                Assert.Equal(BookKeepingReceiptKind.Invoice, receiptKind);
+                return (new System.DateTime(2024, 3, 1), new System.DateTime(2024, 3, 31));
+            });
+
+        Assert.Equal(new System.DateTime(2024, 3, 1), result.From);
+        Assert.Equal(new System.DateTime(2024, 3, 31), result.To);
+    }
+
+    [Fact]
+    public void ApplyHeaderBillingPeriodFromPositions_UsesMinMaxAndKeepsSameDayPeriod()
+    {
+        var export = ItemWith(
+            new ZugferdExportPositionItem
+            {
+                BillingPeriodFrom = new System.DateTime(2024, 2, 15),
+                BillingPeriodTo = new System.DateTime(2024, 2, 15),
+            },
+            new ZugferdExportPositionItem
+            {
+                BillingPeriodFrom = new System.DateTime(2024, 1, 1),
+                BillingPeriodTo = new System.DateTime(2024, 3, 31),
+            });
+
+        InvoiceZugferdBL.ApplyHeaderBillingPeriodFromPositions(export);
+
+        Assert.Equal(new System.DateTime(2024, 1, 1), export.BillingPeriodFrom);
+        Assert.Equal(new System.DateTime(2024, 3, 31), export.BillingPeriodTo);
+    }
+
+    [Fact]
+    public void IsSingleServicePeriodDate_ReturnsTrue_WhenDatesAreEqualIgnoringTime()
+    {
+        var isSingleDate = InvoiceZugferdBL.IsSingleServicePeriodDate(
+            new System.DateTime(2026, 2, 6, 10, 0, 0),
+            new System.DateTime(2026, 2, 6, 13, 30, 0));
+
+        Assert.True(isSingleDate);
+    }
+
+    [Fact]
+    public void GetHeaderDeliveryDate_UsesServicePeriodTo_WhenHeaderPeriodIsSingleDate()
+    {
+        var exportItem = ItemWith();
+        exportItem.ReceiptDate = new System.DateTime(2026, 2, 1);
+        exportItem.DeliveryDate = new System.DateTime(2026, 2, 4);
+        exportItem.BillingPeriodFrom = new System.DateTime(2026, 2, 6, 10, 0, 0);
+        exportItem.BillingPeriodTo = new System.DateTime(2026, 2, 6, 13, 30, 0);
+
+        var deliveryDate = InvoiceZugferdBL.GetHeaderDeliveryDate(exportItem);
+
+        Assert.Equal(new System.DateTime(2026, 2, 6), deliveryDate);
+    }
+
+    [Fact]
+    public void DoCreateActualDeliverySupplyChainEvent_UsesOnlyDeliveryDateWhenPeriodDatesAreEqual()
+    {
+        var document = new System.Xml.XmlDocument();
+
+        var node = InvoiceZugferdBL.DoCreateActualDeliverySupplyChainEvent(
+            new System.DateTime(2026, 2, 6, 13, 30, 0),
+            document);
+
+        var occurrenceDateTimeNode = Assert.Single(node.ChildNodes.Cast<System.Xml.XmlNode>(), f => f.LocalName == "OccurrenceDateTime");
+        var dateTimeStringNode = Assert.Single(occurrenceDateTimeNode.ChildNodes.Cast<System.Xml.XmlNode>(), f => f.LocalName == "DateTimeString");
+        Assert.Equal("102", dateTimeStringNode.Attributes?["format"]?.Value);
+        Assert.Equal("20260206", dateTimeStringNode.InnerText);
+    }
+
+    [Fact]
+    public void DoCreateBillingSpecifiedPeriod_UsesStartAndEndDateWhenDatesDiffer()
+    {
+        var document = new System.Xml.XmlDocument();
+
+        var node = InvoiceZugferdBL.DoCreateBillingSpecifiedPeriod(
+            new System.DateTime(2026, 2, 6, 10, 0, 0),
+            new System.DateTime(2026, 2, 7, 13, 30, 0),
+            document);
+
+        var startDateTimeNode = Assert.Single(node.ChildNodes.Cast<System.Xml.XmlNode>(), f => f.LocalName == "StartDateTime");
+        var endDateTimeNode = Assert.Single(node.ChildNodes.Cast<System.Xml.XmlNode>(), f => f.LocalName == "EndDateTime");
+
+        Assert.Equal("20260206", startDateTimeNode.InnerText);
+        Assert.Equal("20260207", endDateTimeNode.InnerText);
+    }
+}