Improve Visio authoring safety and round-trip fidelity

OfficeIMO.Tests/Visio.ConnectionPoints.cs

@@ -196,6 +196,130 @@ public void SparseConnectionPointIndicesDoNotFallbackToSequentialGlueWhenReferen
             Assert.Same(loaded.Pages[0].Shapes[1].ConnectionPoints[0], loadedConnector.ToConnectionPoint);
         }
 
+        [Fact]
+        public void UnresolvedConnectionCellReferencesArePreservedOnRoundTrip() {
+            string filePath = Path.Combine(Path.GetTempPath(), Guid.NewGuid() + ".vsdx");
+
+            VisioDocument document = VisioDocument.Create(filePath);
+            VisioPage page = document.AddPage("Page-1");
+
+            VisioShape from = new("1", 2, 2, 2, 2, "From");
+            page.Shapes.Add(from);
+
+            VisioShape to = new("2", 6, 2, 2, 2, "To");
+            page.Shapes.Add(to);
+
+            page.Connectors.Add(new VisioConnector(from, to));
+            document.Save();
+
+            RewritePage(filePath, pageXml => {
+                XNamespace ns = "http://schemas.microsoft.com/office/visio/2012/main";
+
+                foreach (XElement connect in pageXml.Root!.Element(ns + "Connects")!.Elements(ns + "Connect")) {
+                    if ((string?)connect.Attribute("FromCell") == "BeginX") {
+                        connect.SetAttributeValue("ToCell", "LocPinX");
+                    } else if ((string?)connect.Attribute("FromCell") == "EndX") {
+                        connect.SetAttributeValue("ToCell", "Width");
+                    }
+                }
+            });
+
+            VisioDocument loaded = VisioDocument.Load(filePath);
+            VisioConnector loadedConnector = Assert.Single(loaded.Pages[0].Connectors);
+            Assert.Null(loadedConnector.FromConnectionPoint);
+            Assert.Null(loadedConnector.ToConnectionPoint);
+
+            loaded.Save();
+
+            XNamespace verifyNs = "http://schemas.microsoft.com/office/visio/2012/main";
+            XElement[] connectRows = ReadPage(filePath).Root!.Element(verifyNs + "Connects")!.Elements(verifyNs + "Connect").ToArray();
+            Assert.Equal("LocPinX", connectRows.First(e => (string?)e.Attribute("FromCell") == "BeginX").Attribute("ToCell")?.Value);
+            Assert.Equal("Width", connectRows.First(e => (string?)e.Attribute("FromCell") == "EndX").Attribute("ToCell")?.Value);
+        }
+
+        [Fact]
+        public void ExtraConnectAttributesArePreservedOnRoundTrip() {
+            string filePath = Path.Combine(Path.GetTempPath(), Guid.NewGuid() + ".vsdx");
+
+            VisioDocument document = VisioDocument.Create(filePath);
+            VisioPage page = document.AddPage("Page-1");
+
+            VisioShape from = new("1", 2, 2, 2, 2, "From");
+            VisioShape to = new("2", 6, 2, 2, 2, "To");
+            page.Shapes.Add(from);
+            page.Shapes.Add(to);
+            page.Connectors.Add(new VisioConnector(from, to));
+            document.Save();
+
+            RewritePage(filePath, pageXml => {
+                XNamespace ns = "http://schemas.microsoft.com/office/visio/2012/main";
+
+                foreach (XElement connect in pageXml.Root!.Element(ns + "Connects")!.Elements(ns + "Connect")) {
+                    if ((string?)connect.Attribute("FromCell") == "BeginX") {
+                        connect.SetAttributeValue("ToPart", "9");
+                        connect.SetAttributeValue("Del", "1");
+                    } else if ((string?)connect.Attribute("FromCell") == "EndX") {
+                        connect.SetAttributeValue("ToPart", "12");
+                    }
+                }
+            });
+
+            VisioDocument loaded = VisioDocument.Load(filePath);
+            loaded.Save();
+
+            XNamespace verifyNs = "http://schemas.microsoft.com/office/visio/2012/main";
+            XElement[] connectRows = ReadPage(filePath).Root!.Element(verifyNs + "Connects")!.Elements(verifyNs + "Connect").ToArray();
+            XElement begin = connectRows.First(e => (string?)e.Attribute("FromCell") == "BeginX");
+            XElement end = connectRows.First(e => (string?)e.Attribute("FromCell") == "EndX");
+            Assert.Equal("9", begin.Attribute("ToPart")?.Value);
+            Assert.Equal("1", begin.Attribute("Del")?.Value);
+            Assert.Equal("12", end.Attribute("ToPart")?.Value);
+        }
+
+        [Fact]
+        public void ReconnectClearsPreservedAttributesOnlyForUpdatedEndpoint() {
+            string filePath = Path.Combine(Path.GetTempPath(), Guid.NewGuid() + ".vsdx");
+
+            VisioDocument document = VisioDocument.Create(filePath);
+            VisioPage page = document.AddPage("Page-1");
+
+            VisioShape from = new("1", 2, 2, 2, 2, "From");
+            VisioShape replacement = new("2", 4, 2, 2, 2, "Replacement");
+            VisioShape to = new("3", 7, 2, 2, 2, "To");
+            page.Shapes.Add(from);
+            page.Shapes.Add(replacement);
+            page.Shapes.Add(to);
+            page.Connectors.Add(new VisioConnector(from, to));
+            document.Save();
+
+            RewritePage(filePath, pageXml => {
+                XNamespace ns = "http://schemas.microsoft.com/office/visio/2012/main";
+
+                foreach (XElement connect in pageXml.Root!.Element(ns + "Connects")!.Elements(ns + "Connect")) {
+                    if ((string?)connect.Attribute("FromCell") == "BeginX") {
+                        connect.SetAttributeValue("ToPart", "9");
+                    } else if ((string?)connect.Attribute("FromCell") == "EndX") {
+                        connect.SetAttributeValue("ToPart", "12");
+                    }
+                }
+            });
+
+            VisioDocument loaded = VisioDocument.Load(filePath);
+            VisioPage loadedPage = loaded.Pages[0];
+            VisioConnector connector = Assert.Single(loadedPage.Connectors);
+
+            loadedPage.ReconnectConnectorStart(connector, loadedPage.Shapes[1], VisioSide.Left);
+            loaded.Save();
+
+            XNamespace verifyNs = "http://schemas.microsoft.com/office/visio/2012/main";
+            XElement[] connectRows = ReadPage(filePath).Root!.Element(verifyNs + "Connects")!.Elements(verifyNs + "Connect").ToArray();
+            XElement begin = connectRows.First(e => (string?)e.Attribute("FromCell") == "BeginX");
+            XElement end = connectRows.First(e => (string?)e.Attribute("FromCell") == "EndX");
+            Assert.Null(begin.Attribute("ToPart"));
+            Assert.Equal("Connections.X1", begin.Attribute("ToCell")?.Value);
+            Assert.Equal("12", end.Attribute("ToPart")?.Value);
+        }
+
         private static XDocument ReadPage(string vsdxPath) {
             using FileStream stream = File.Open(vsdxPath, FileMode.Open, FileAccess.Read, FileShare.ReadWrite);
             using ZipArchive archive = new(stream, ZipArchiveMode.Read);

OfficeIMO.Tests/Visio.DocumentValidation.cs

@@ -1,6 +1,7 @@
 using System;
 using System.IO;
 using System.Linq;
+using System.Reflection;
 using OfficeIMO.Visio;
 using Xunit;
 
@@ -64,5 +65,60 @@ public void ValidateReportsNegativeDimensionsAndDetachedConnectionPoints() {
             Assert.Contains(issues, issue => issue.Contains("cannot have a negative height"));
             Assert.Contains(issues, issue => issue.Contains("source connection point"));
         }
+
+        [Fact]
+        public void SaveRejectsInvalidDocumentsWithValidationSummary() {
+            string filePath = Path.Combine(Path.GetTempPath(), Guid.NewGuid() + ".vsdx");
+            VisioDocument document = VisioDocument.Create(filePath);
+            VisioPage first = document.AddPage("Page-1", id: 0);
+            VisioPage second = document.AddPage("Page-2", id: 0);
+
+            VisioShape shared = new("dup", 1, 1, 1, 1, "Shared");
+            first.Shapes.Add(shared);
+            second.Shapes.Add(new VisioShape("outside", 2, 2, 1, 1, "Outside"));
+            first.Connectors.Add(new VisioConnector("dup", shared, second.Shapes[0]));
+
+            InvalidOperationException exception = Assert.Throws<InvalidOperationException>(() => document.Save());
+
+            Assert.Contains("validation failed", exception.Message);
+            Assert.Contains("Duplicate page id '0'", exception.Message);
+            Assert.Contains("references a target shape that is not part of the page", exception.Message);
+        }
+
+        [Fact]
+        public void ValidateReportsNegativePageIds() {
+            VisioDocument document = VisioDocument.Create(Path.Combine(Path.GetTempPath(), Guid.NewGuid() + ".vsdx"));
+            VisioPage page = new("Detached") { Id = -1 };
+
+            object? rawPages = typeof(VisioDocument)
+                .GetField("_pages", System.Reflection.BindingFlags.Instance | System.Reflection.BindingFlags.NonPublic)!
+                .GetValue(document);
+            var pagesList = Assert.IsType<System.Collections.Generic.List<VisioPage>>(rawPages);
+            pagesList.Add(page);
+
+            string[] issues = document.Validate().ToArray();
+
+            Assert.Contains(issues, issue => issue.Contains("must have a non-negative id"));
+        }
+
+        [Fact]
+        public void ValidateReportsCyclicShapeHierarchyWithoutRecursingForever() {
+            VisioDocument document = VisioDocument.Create(Path.Combine(Path.GetTempPath(), Guid.NewGuid() + ".vsdx"));
+            VisioPage page = document.AddPage("Page-1");
+            VisioShape group = new("1") { Type = "Group" };
+            VisioShape child = new("2", 1, 1, 1, 1, "Child");
+            group.Children.Add(child);
+            page.Shapes.Add(group);
+
+            List<VisioShape> rawChildren = Assert.IsType<List<VisioShape>>(typeof(VisioShape)
+                .GetField("_children", BindingFlags.Instance | BindingFlags.NonPublic)!
+                .GetValue(child));
+            rawChildren.Add(group);
+
+            string[] issues = document.Validate().ToArray();
+
+            Assert.Contains(issues, issue => issue.Contains("cyclic parent/child hierarchy"));
+            Assert.Contains(issues, issue => issue.Contains("inconsistent parent reference"));
+        }
     }
 }

OfficeIMO.Tests/Visio.Fluent.cs

@@ -74,6 +74,26 @@ public void FluentConnectCanTargetSidesAndStyleLines() {
             Assert.Equal(EndArrow.Triangle, connector.EndArrow);
         }
 
+        [Fact]
+        public void FluentConnectUsesPageScopedConnectorIdsAcrossDocuments() {
+            static VisioDocument CreateDocument(string filePath) {
+                VisioDocument document = VisioDocument.Create(filePath);
+                document.AsFluent()
+                    .Page("Page1", p => p
+                        .Rect("1", 1, 1, 2, 1, "Left")
+                        .Rect("2", 5, 1, 2, 1, "Right")
+                        .Connect("1", "2"))
+                    .End();
+                return document;
+            }
+
+            VisioDocument first = CreateDocument(Path.Combine(Path.GetTempPath(), Guid.NewGuid() + ".vsdx"));
+            VisioDocument second = CreateDocument(Path.Combine(Path.GetTempPath(), Guid.NewGuid() + ".vsdx"));
+
+            Assert.Equal("3", Assert.Single(first.Pages[0].Connectors).Id);
+            Assert.Equal("3", Assert.Single(second.Pages[0].Connectors).Id);
+        }
+
         [Fact]
         public void SideSelectionUsesNamedSidePointEvenWhenCustomPointsExist() {
             string filePath = Path.Combine(Path.GetTempPath(), Guid.NewGuid() + ".vsdx");