move projects to src folder

src/DotNetSolutionTools.Core/SolutionProjectParity.cs

@@ -0,0 +1,43 @@
+using DotNetSolutionTools.Core.Common;
+using Microsoft.Build.Construction;
+
+namespace DotNetSolutionTools.Core;
+
+public static class SolutionProjectParity
+{
+    public static List<string> CompareSolutionAndCSharpProjects(string solutionFolderPath, string solutionFilePath)
+    {
+        var csprojList = CsprojHelper.RetrieveAllCSharpProjectFullPathsFromFolder(solutionFolderPath);
+        var solutionFile = SlnHelper.ParseSolutionFileFromPath(solutionFilePath);
+        ArgumentNullException.ThrowIfNull(solutionFile);
+        var projectsMissingFromSolution = FindProjectsMissingFromSolution(csprojList, solutionFile);
+
+        return projectsMissingFromSolution;
+    }
+
+    public static List<string> FindProjectsMissingFromSolution(string[] csprojList, SolutionFile solutionFile)
+    {
+        var projects = solutionFile.ProjectsInOrder;
+        var projectsMissingFromSolution = new List<string>();
+
+        foreach (var project in csprojList)
+        {
+            var projectInSolution = projects.FirstOrDefault(x =>
+                NormalizePath(x.AbsolutePath) == NormalizePath(project)
+            );
+
+            if (projectInSolution == null)
+            {
+                projectsMissingFromSolution.Add(project);
+            }
+        }
+
+        return projectsMissingFromSolution;
+    }
+
+    private static string NormalizePath(string path)
+    {
+        return Path.GetFullPath(new Uri(path).LocalPath)
+            .TrimEnd(Path.DirectorySeparatorChar, Path.AltDirectorySeparatorChar);
+    }
+}