using System;
using System.Collections.Generic;
using System.Drawing;
using System.Runtime.InteropServices;
using System.Windows.Forms;

// The 'windowHandle' parameter will contain the window handle for the:
//   - Active window when run by hotkey
//   - Window Location target when run by a Window Location rule
//   - TitleBar Button owner when run by a TitleBar Button
//   - Jump List owner when run from a Taskbar Jump List
//   - Currently focused window if none of these match
public static class DisplayFusionFunction
{
	[DllImport("user32.dll", SetLastError = true)]
	static extern IntPtr GetWindow(IntPtr hWnd, uint uCmd);
	
	//some constants
	const uint GW_HWNDNEXT = 2;
	
	public static void Run(IntPtr windowHandle)
	{          
        // Get a list of each visible window on our monitors, and throw them in a HashSet		
        HashSet<IntPtr> visibleWindows = new HashSet<IntPtr>(BFS.Window.GetVisibleAndMinimizedWindowHandles());
        
		// A list to store the windows
		List<WindowInfo> windows = new List<WindowInfo>();
		
        // Enumerate through the monitors, starting with the focused window, and moving down
		int order = 0;
		for(IntPtr window = BFS.Window.GetFocusedWindow(); ; window = GetWindow(window, GW_HWNDNEXT))
		{
			// Check to see if there are any windows left
			if(window == IntPtr.Zero)
				break;
			
			// If it is a window we should ignore, ignore it
			if(IsDisplayFusionWindowOrHiddenExplorerWindow(window))
				continue;
			
			// Check to see if the window exists in the hashset.
			// If it does, store it
			if(!visibleWindows.Contains(window))
				continue;
			
			// Store the window with its info
            windows.Add(new WindowInfo(window, order++));
		}
        
        // Save the windows
		BFS.ScriptSettings.WriteValue("WindowInfoList", System.Text.Json.JsonSerializer.Serialize(windows));
	}
	
	private static bool IsDisplayFusionWindowOrHiddenExplorerWindow(IntPtr window)
	{
        // Ignore any DisplayFusion windows (title bar buttons, etc.)
        // Ignore pesky hidden explorer.exe windows
        string windowClass = BFS.Window.GetClass(window);
        if((windowClass.StartsWith("DF", StringComparison.OrdinalIgnoreCase)) ||
            (windowClass.Equals("EdgeUiInputTopWndClass", StringComparison.OrdinalIgnoreCase)) ||
            (windowClass.Equals("EdgeUiInputWndClass", StringComparison.OrdinalIgnoreCase)) ||
            (windowClass.Equals("NativeHWNDHost", StringComparison.OrdinalIgnoreCase)) ||
            (windowClass.Equals("ModeInputWnd", StringComparison.OrdinalIgnoreCase)) ||
            (windowClass.Equals("MetroGhostWindow", StringComparison.OrdinalIgnoreCase)) ||
            (windowClass.Equals("ImmersiveLauncher", StringComparison.OrdinalIgnoreCase)) ||
            (windowClass.Equals("ApplicationManager_ImmersiveShellWindow", StringComparison.OrdinalIgnoreCase)) ||
            (windowClass.Equals("Shell_TrayWnd", StringComparison.OrdinalIgnoreCase)) ||
            (windowClass.Equals("WorkerW", StringComparison.OrdinalIgnoreCase)) ||
            (windowClass.Equals("Progman", StringComparison.OrdinalIgnoreCase)) ||
            (windowClass.Equals("SearchPane", StringComparison.OrdinalIgnoreCase)))
        {
            return true;
        }
        
        return false;
	}
	
	public class WindowInfo
	{
		public long Handle { get; set; }
		public FormWindowState State { get; set; }
		public Rectangle Bounds { get; set; }
		public int ZOrder { get; set; }
		
		public WindowInfo(IntPtr handle, int zOrder)
		{
			this.Handle = handle.ToInt64();
			if(BFS.Window.IsMinimized(handle))
				this.State = FormWindowState.Minimized;			
			else if(BFS.Window.IsMaximized(handle))
				this.State = FormWindowState.Maximized;
			else
				this.State = FormWindowState.Normal;
			
			this.Bounds = BFS.Window.GetBounds(handle);
			this.ZOrder = zOrder;
		}
	}
}