JNA Platform

import com.sun.jna.platform.FileUtils;
import com.sun.jna.platform.WindowUtils;
import com.sun.jna.platform.KeyboardUtils;
import com.sun.jna.platform.EnumUtils;
import com.sun.jna.platform.dnd.DragHandler;
import com.sun.jna.platform.dnd.DropHandler;
import com.sun.jna.platform.win32.Kernel32;
import com.sun.jna.platform.win32.User32;
import com.sun.jna.platform.unix.LibC;
import com.sun.jna.platform.mac.CoreFoundation;

import com.sun.jna.platform.FileUtils;
import com.sun.jna.platform.WindowUtils;
import com.sun.jna.platform.win32.Kernel32;
import com.sun.jna.platform.win32.User32;
import com.sun.jna.platform.win32.WinDef.HWND;

// Cross-platform file operations
FileUtils fileUtils = FileUtils.getInstance();
fileUtils.moveToTrash(new File("temp.txt"));

// Cross-platform window manipulation  
WindowUtils.setWindowAlpha(window, 0.5f); // 50% transparency

// Windows-specific system calls (when on Windows)
if (Platform.isWindows()) {
    HWND hwnd = User32.INSTANCE.FindWindow(null, "Calculator");
    if (hwnd != null) {
        User32.INSTANCE.ShowWindow(hwnd, User32.SW_MAXIMIZE);
    }
    
    // Get system information
    int processId = Kernel32.INSTANCE.GetCurrentProcessId();
    System.out.println("Current PID: " + processId);
}

// File operations
public abstract class FileUtils {
    public static FileUtils getInstance();
    public abstract void moveToTrash(File... files) throws IOException;
    public abstract boolean hasTrash();
}

// Window manipulation and effects
public class WindowUtils {
    public static void setWindowMask(Window w, Shape mask);
    public static void setWindowAlpha(Window w, float alpha);
    public static void setWindowTransparent(Window w, boolean transparent);
    public static List<DesktopWindow> getAllWindows(boolean onlyVisible);
    public static BufferedImage getWindowIcon(HWND hwnd);
    public static String getWindowTitle(HWND hwnd);
}

// Keyboard state access
public class KeyboardUtils {
    public static boolean isPressed(int keycode);
    public static boolean isPressed(int keycode, int location);
}

// Enum conversion utilities
public class EnumUtils {
    public static <E extends Enum<E>> int toInteger(E val);
    public static <E extends Enum<E>> E fromInteger(int idx, Class<E> clazz);
    public static <T extends FlagEnum> Set<T> setFromInteger(int flags, Class<T> clazz);
    public static <T extends FlagEnum> int setToInteger(Set<T> set);
}

// Core Windows APIs
public interface Kernel32 extends StdCallLibrary, WinNT, Wincon {
    Kernel32 INSTANCE = Native.load("kernel32", Kernel32.class, W32APIOptions.DEFAULT_OPTIONS);
    
    boolean CreateProcess(String lpApplicationName, String lpCommandLine, 
                         WinBase.SECURITY_ATTRIBUTES lpProcessAttributes,
                         WinBase.SECURITY_ATTRIBUTES lpThreadAttributes,
                         boolean bInheritHandles, DWORD dwCreationFlags,
                         Pointer lpEnvironment, String lpCurrentDirectory,
                         WinBase.STARTUPINFO lpStartupInfo,
                         WinBase.PROCESS_INFORMATION lpProcessInformation);
    
    HANDLE OpenProcess(DWORD dwDesiredAccess, boolean bInheritHandle, DWORD dwProcessId);
    DWORD GetCurrentProcessId();
    DWORD GetLastError();
}

public interface User32 extends StdCallLibrary, WinUser, WinNT {
    User32 INSTANCE = Native.load("user32", User32.class, W32APIOptions.DEFAULT_OPTIONS);
    
    HWND FindWindow(String lpClassName, String lpWindowName);
    int GetWindowText(HWND hWnd, char[] lpString, int nMaxCount);
    LRESULT SendMessage(HWND hWnd, int Msg, WPARAM wParam, LPARAM lParam);
    boolean ShowWindow(HWND hWnd, int nCmdShow);
}

// Unix/Linux system calls
public interface LibC extends Library {
    LibC INSTANCE = Native.load("c", LibC.class);
    
    int open(String path, int flags);
    int close(int fd);
    int read(int fd, Buffer buffer, int count);
    int write(int fd, Buffer buffer, int count);
    int chmod(String path, int mode);
}

// X Window System
public interface X11 extends Library {
    X11 INSTANCE = Native.load("X11", X11.class);
    
    Display XOpenDisplay(String display_name);
    int XCloseDisplay(Display display);
    Window XCreateSimpleWindow(Display display, Window parent, int x, int y, 
                              int width, int height, int border_width, 
                              long border, long background);
}

// Core Foundation framework
public interface CoreFoundation extends Library {
    CoreFoundation INSTANCE = Native.load("CoreFoundation", CoreFoundation.class);
    
    CFStringRef CFStringCreateWithCString(CFAllocatorRef alloc, String cStr, int encoding);
    void CFRelease(CFTypeRef cf);
    CFTypeID CFGetTypeID(CFTypeRef cf);
}

// I/O Kit framework
public interface IOKit extends Library {
    IOKit INSTANCE = Native.load("IOKit", IOKit.class);
    
    CFMutableDictionaryRef IOServiceMatching(String name);
    int IOServiceGetMatchingServices(int masterPort, CFDictionaryRef matching, 
                                   Pointer existing);
}

// Base COM interface
public interface IUnknown {
    HRESULT QueryInterface(REFIID riid, PointerByReference ppvObject);
    int AddRef();
    int Release();
}

// COM automation interface  
public interface IDispatch extends IUnknown {
    HRESULT GetTypeInfoCount(IntByReference pctinfo);
    HRESULT GetTypeInfo(int iTInfo, LCID lcid, PointerByReference ppTInfo);
    HRESULT Invoke(DISPID dispIdMember, REFIID riid, LCID lcid, WORD wFlags,
                   DISPPARAMS.ByReference pDispParams, VARIANT.ByReference pVarResult,
                   EXCEPINFO.ByReference pExcepInfo, IntByReference puArgErr);
}

// Drag handling with ghosted images
public abstract class DragHandler {
    protected DragHandler(Component dragSource, int actions);
    public static Transferable getTransferable(DropTargetEvent e);
}

// Drop handling with visual feedback
public abstract class DropHandler implements DropTargetListener {
    public DropHandler(Component dropTarget, int actions);
    public boolean isActive();
    public void setActive(boolean active);
}

// Ghosted drag images
public class GhostedDragImage {
    public GhostedDragImage(Component dragSource, Icon icon, Point initialScreenLoc, Point cursorOffset);
    public void setAlpha(float alpha);
    public void move(Point screenLocation);
    public void dispose();
}

// Windows types
public class WinDef {
    public static class HWND extends HANDLE { }
    public static class DWORD extends IntegerType { }
    public static class WORD extends IntegerType { }
    public static class LRESULT extends IntegerType { }
    public static class WPARAM extends IntegerType { }
    public static class LPARAM extends IntegerType { }
    public static class RECT extends Structure {
        public int left, top, right, bottom;
    }
    public static class POINT extends Structure {
        public int x, y;
    }
}

// Cross-platform window information
public class DesktopWindow {
    private HWND hwnd;
    private String title;
    private String filePath;
    private Rectangle bounds;
}