Comparing folders testing (working)

compareFolders.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace CheckFolder {
	class Program {
		public static List<Folder> toAddList;
		static void Main(string[] args) {
			var newFolders = new List<Folder>();
			Folder mainFolder, otherFolder;
			var r = new Random();
			setup(r, "sub 0", out mainFolder, subLevels: 20, maxFolders: 20); // simulates existing folder
			setup(r, "sub 0", out otherFolder, subLevels: 20, maxFolders: 20); // simulates drop folder

			Console.WriteLine(" --- Folders ---");
			printFolder(mainFolder);
			Console.WriteLine("");
			printFolder(otherFolder);

			Console.WriteLine("");
			Console.WriteLine(" --- Comparing ---");
			compareFolders(mainFolder, otherFolder, newFolders);

			Console.WriteLine("");
			Console.WriteLine(" --- New Folders ---");
			printNewFolders(newFolders);
#if DEBUG
			Console.WriteLine("Press enter to close...");
			Console.ReadLine();
#endif
		}

		private static void printNewFolders(List<Folder> newFolders) {
			newFolders.ForEach(i => Console.WriteLine("Create folder:" + i.title));
		}
	
		private static void compareFolders(Folder folder1, Folder folder2, List<Folder> newFolders) {
			if (folder2.childs != null) {
				if (folder1.childs != null) {
					// check for folder 2 childs not in folder 1
					newFolders.AddRange(folder2.childs.FindAll(f => !folder1.childs.Select(f2 => f2.title).ToList().Contains(f.title)));
					// for similar folders go one deeper
					folder1.childs.FindAll(f => folder2.childs.Select(f2 => f2.title).ToList().Contains(f.title)).ForEach(f1 => compareFolders(f1, folder2.childs.Find(f2 => f2.title == f1.title), newFolders));
				} else {
					// folder 1 doesn't have childs so add all of folder2
					newFolders.AddRange(folder2.childs);
				}
			}
		}

		private static void printFolder(Folder node, bool printfiles = false, int index = 0) {
			// Print folder name
			for (int i = 0; i < index; i++) Console.Write(" > ");
			Console.WriteLine(node.ToString());
			// Print files
			if (node.files != null && node.files.Count > 0 && printfiles) {
				foreach (File file in node.files) {
					for (int i = 0; i < index; i++) Console.Write(" > ");
					Console.WriteLine(" > " + file.ToString());
				}
			}

			// Print childs if 
			if (node.childs != null) {
				index++;
				foreach (Folder sub in node.childs) {
					printFolder(sub, printfiles, index);
				}
			}
		}


		#region setup
		private static void addFiles(Folder folder, int amount) {
			for (int i = 0; i < amount; i++) {
				folder.addFile(new File("Test File " + i));
			}
		}

		private static void setup(Random r, string title, out Folder root, int subLevels, int maxFolders = 5) {
			root = new Folder(title);
			var rootSubFolder = 2;


			for (int i = 0; i < rootSubFolder; i++) {
				var sub = new Folder(root.title + " sub " + i);
				createFolders(r, sub, subLevels, maxFolders: maxFolders);
				root.addSubFolder(sub);
			}
		}


		private static void createFolders(Random r, Folder folder, int maxindex = 1, int index = 0, int maxFolders = 5) {
			index++;
			for (int i = 0; i < r.Next() % maxFolders-1; i++) {
				// make new sub folder
				var title = "";
				title += folder.title + " ";
				title += "sub " + i;
				var fol = new Folder(title);

				// add some files
				addFiles(fol, r.Next() % 5);

				// append to root
				folder.addSubFolder(fol);
			}

			if (index < maxindex - 1 && folder.childs != null && folder.childs.Count > 0) {
				foreach (Folder sub in folder.childs) {
					createFolders(r, sub, maxindex, index);
				}
			}
		}
		#endregion
	}
	#region classes
	public class Folder : document {
		public List<Folder> childs;
		public List<File> files;

		public Folder(string title) :
			base(title) {
		}

		public void addSubFolder(Folder child) {
			if (childs == null) childs = new List<Folder>();
			childs.Add(child);
			child.root = this;
		}
		public void addFile(File file) {
			if (files == null) files = new List<File>();
			files.Add(file);
			file.root = this;
		}

		public string ToString() {
			string output = "Fo: " + title;

			if (childs != null && childs.Count > 0 || files != null && files.Count > 0) {
				output += " (";
				if (childs != null && childs.Count > 0) output += "fo: " + childs.Count;
				if (childs != null && childs.Count > 0 && files != null && files.Count > 0) output += ", ";
				if (files != null && files.Count > 0) output += "fi: " + files.Count;
				output += ")";
			}
			return output;
		}
	}
	public class File : document {
		public File(string title) :
			base(title) {
		}

		public string ToString() {
			string output = "Fi: " + title;

			return output;
		}
	}

	public class document {
		public string title;
		public Folder root;

		public document(string title) {
			this.title = title;
		}
	}
	#endregion
}