Mk2Rev1

various bugfixes and such.
also bookmarks, temp song loaderm and undo overhaul with near complete multiplayer, but menu items disabled. i really wish i could split this into multiple commits, but i don't know how to work unreal.

Plugins/ZipUtility-ue4/Source/WindowsUtility/Public/WindowsFileUtilityFunctionLibrary.h

@@ -0,0 +1,74 @@
+#pragma once
+
+#include "WFULambdaRunnable.h"
+#include "WindowsFileUtilityFunctionLibrary.generated.h"
+
+//Struct to Track which delegate is watching files
+struct FWatcher
+{
+	UObject* Delegate;
+	
+	FString Path;
+
+	WFULambdaRunnable* Runnable = nullptr;
+
+	FThreadSafeBool ShouldRun = true;
+	
+};
+
+inline bool operator==(const FWatcher& lhs, const FWatcher& rhs)
+{
+	return lhs.Delegate == rhs.Delegate;
+}
+
+UCLASS(ClassGroup = WindowsFileUtility, Blueprintable)
+class WINDOWSFILEUTILITY_API UWindowsFileUtilityFunctionLibrary : public UBlueprintFunctionLibrary
+{
+	GENERATED_UCLASS_BODY()
+
+		
+	UFUNCTION(BlueprintCallable, Category = WindowsFileUtility)
+	static bool DoesFileExist(const FString& FullPath);
+
+	/*Expects full path including name. you can use this function to rename files.*/
+	UFUNCTION(BlueprintCallable, Category = WindowsFileUtility)
+	static bool MoveFileTo(const FString& From, const FString& To);
+
+	/*Expects full path including folder name.*/
+	UFUNCTION(BlueprintCallable, Category = WindowsFileUtility)
+	static bool CreateDirectoryAt(const FString& FullPath);
+
+	/*Deletes file (not directory). Expects full path.*/
+	UFUNCTION(BlueprintCallable, Category = WindowsFileUtility)
+	static bool DeleteFileAt(const FString& FullPath);
+
+	/*Deletes empty folders only. Expects full path.*/
+	UFUNCTION(BlueprintCallable, Category = WindowsFileUtility)
+	static bool DeleteEmptyFolder(const FString& FullPath);
+
+	/*Dangerous function, not exposed to blueprint. */
+	UFUNCTION(BlueprintCallable, Category = WindowsFileUtility)
+	static bool DeleteFolderRecursively(const FString& FullPath);
+
+	/** Watch a folder for change. WatcherDelegate should respond to FolderWatchInterface*/
+	UFUNCTION(BlueprintCallable, Category = WindowsFileUtility)
+	static void WatchFolder(const FString& FullPath, UObject* WatcherDelegate);
+
+	/** Stop watching a folder for change. WatcherDelegate should respond to FolderWatchInterface*/
+	UFUNCTION(BlueprintCallable, Category = WindowsFileUtility)
+	static void StopWatchingFolder(const FString& FullPath, UObject* WatcherDelegate);
+
+	/** List the contents, expects UFileListInterface*/
+	UFUNCTION(BlueprintCallable, Category = WindowsFileUtility)
+	static void ListContentsOfFolder(const FString& FullPath, UObject* ListDelegate);
+
+	//Convenience C++ callback
+	static void ListContentsOfFolderToCallback(const FString& FullPath, TFunction<void(const TArray<FString>&, const TArray<FString>&)> OnListCompleteCallback);
+
+	//Todo: add watch folder with threadsafe boolean passthrough
+	//static void ListContentsOfFolderToCallback(const FString& FullPath, TFunction<void(const TArray<FString>&, const TArray<FString>&)> OnListCompleteCallback);
+
+private:
+	static void WatchFolderOnBgThread(const FString& FullPath, const FWatcher* Watcher);
+	static TMap<FString, TArray<FWatcher>> Watchers;
+};