Attempt to fix #15: Fix AASX files of old version

src/Program.cs

@@ -84,6 +84,8 @@ private void Run(string inputFileName, string outputFileName, bool unfix)
         new RelationshipFixer().Fix(package, _fixes);
         new RelationshipDefinitionFixer().Fix(package, _fixes);
         new ExternalReferenceFixer(package).Fix();
+        new VersionFixer(package).Fix();
+
 
         // DisplayContentsForDebuggingPurposes(package);
         package.Flush();
@@ -118,6 +120,9 @@ private static void PrintUsage()
         Console.WriteLine("Fixes the external reference issue (bug #681) in an AASX file.");
         Console.WriteLine("This will only be done one-way, since Package Explorer can open fixed files.");
         Console.WriteLine();
+        Console.WriteLine("Brings files from AASX version 1 to AASX version 3 by converting XML documents to the new namespace.");
+        Console.WriteLine("This will only be done one-way, since Package Explorer can open fixed files.");
+        Console.WriteLine();
         Console.WriteLine("Usage: AASFix <input file name> <output file name> [--fix|--unfix]");
         Console.WriteLine("       <input file name> : source file for reading");
         Console.WriteLine("       <output file name>: destination file for writing");

src/RelationshipDefinitionFixer.cs

@@ -61,6 +61,7 @@ private void FixDefinitionInXml(XDocument xml, List<Fix> fixes)
         private void SaveXml(PackagePart part, XDocument xml)
         {
             using var stream = part.GetStream(FileMode.Open, FileAccess.Write);
+            stream.SetLength(0);
             xml.Save(stream);
         }
     }

src/VersionFixer.cs

@@ -0,0 +1,109 @@
+// Copyright 2023 Lukas Benner, Thomas Weller
+// 
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+// 
+// http://www.apache.org/licenses/LICENSE-2.0
+// 
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+using System.IO.Packaging;
+using System.Xml;
+using System.Xml.Linq;
+using System.Xml.XPath;
+
+namespace AASFix
+{
+    internal class VersionFixer
+    {
+        private readonly PackagePartCollection _parts;
+        private readonly XmlNamespaceManager _nsMgr = new(new NameTable());
+        private readonly XNamespace _version3 = "https://admin-shell.io/aas/3/0";
+        private readonly string _oldVersionNodesQuery;
+        private readonly List<string> _oldVersions = new()
+        {
+            "https://admin-shell.io/aas/1/0",
+            "http://www.admin-shell.io/aas/1/0",
+            "https://www.admin-shell.io/aas/1/0",
+            "https://admin-shell.io/aas/2/0",
+            "http://www.admin-shell.io/aas/2/0",
+            "https://www.admin-shell.io/aas/2/0"
+        };
+
+        internal VersionFixer(Package package)
+        {
+            _parts = package.GetParts();
+            _nsMgr.AddNamespace("aas3", "https://admin-shell.io/aas/3/0");
+            _oldVersionNodesQuery = BuildQueryForOldVersions(_nsMgr, _oldVersions);
+        }
+
+        internal void Fix()
+        {
+            var xmlFiles = FindXmlFiles();
+            foreach (var xmlFile in xmlFiles)
+            {
+                var xml = LoadXml(xmlFile);
+                var incorrectNodes = FindIncorrectNodes(xml);
+                FixNamespace(incorrectNodes);
+                SaveXml(xmlFile, xml);
+            }
+        }
+
+        private IEnumerable<PackagePart> FindXmlFiles()
+        {
+            return _parts.Where(p => p.ContentType == "text/xml");
+        }
+
+        private IEnumerable<XElement> FindIncorrectNodes(XDocument xml)
+        {
+            return xml.XPathSelectElements(_oldVersionNodesQuery, _nsMgr);
+        }
+
+        private void FixNamespace(IEnumerable<XElement> incorrectNodes)
+        {
+            if (incorrectNodes.Any())
+            {
+                Console.WriteLine("Converting XML to version 3.");
+            }
+
+            foreach (var node in incorrectNodes)
+            {
+                node.Name = _version3 + node.Name.LocalName;
+            }
+        }
+
+        private string BuildQueryForOldVersions(XmlNamespaceManager nsMgr, List<string> oldVersions)
+        {
+            var queries = new List<string>();
+            var i= 0;
+            foreach (var version in oldVersions)
+            {
+                i++;
+                var prefix = $"old{i}";
+                queries.Add($"//{prefix}:*");
+                nsMgr.AddNamespace(prefix, version);
+            }
+            return string.Join(" | ", queries);
+        }
+
+        private void SaveXml(PackagePart part, XDocument xml)
+        {
+            using var stream = part.GetStream(FileMode.Open, FileAccess.ReadWrite);
+            stream.Seek(0, SeekOrigin.Begin);
+            stream.SetLength(0);
+            xml.Save(stream);
+        }
+
+        private XDocument LoadXml(PackagePart part)
+        {
+            using var stream = part.GetStream(FileMode.Open, FileAccess.ReadWrite);
+            var xml = XDocument.Load(stream);
+            return xml;
+        }
+    }
+}