using System;
using System.Drawing;
using System.Runtime.InteropServices;

//////////////////////////////////////
// Instructions for setup:
//////////////////////////////////////
//
// 1. Make a trigger to this script with the event 'Window Focused' and process name *.*
//
// 2. Set the primary monitor split: [Advanced Settings] > [Monitor Configuration] > [Force Primary Monitor ID]
// 
// 3. Add Game window trigger criteria below
//
// 4. In each game set the display mode to 'Windowed'
//
//////////////////////////////////////
public static class DisplayFusionFunction
{
	public static bool IsGameWindow(IntPtr hwnd)
	{
		var exePath = BFS.Application.GetMainFileByWindow(hwnd);
		var wndTitle = BFS.Window.GetText(hwnd);
		
		// these are the trigger match criteria to determine what windows count as game windows to this script
		// if using a DisplayFocus trigger to activate this script, then choose 'Window Focused' and *.*
		return 
			(exePath.EndsWith(@"Deep Rock Galactic\FSD\Binaries\Win64\FSD-Win64-Shipping.exe") && wndTitle == "Deep Rock Galactic") ||
			(exePath.EndsWith("SpaceEngineers.exe") && wndTitle == "Space Engineers") ||
			// Space Engineers: also to fix video render resolution to match window size:
			//     edit %APPDATA%\SpaceEngineers\SpaceEngineers.cfg
			//     find <Key>ScreenWidth</Key> and <Key>ScreenHeight</Key>
			//     set their values to the appropriate numbers
			(exePath.EndsWith("Hearthstone.exe") && wndTitle == "Hearthstone") ||
			(exePath.EndsWith("Risk of Rain 2.exe") && wndTitle == "Risk of Rain 2");
	}
	
	public static void Run(IntPtr hwnd)
	{
		string oldFocus = BFS.ScriptSettings.ReadValue("GameWindowFocus");
		long oldHwnd;
		
		if (oldFocus != null && oldFocus.Length > 0 && long.TryParse(oldFocus, out oldHwnd) && oldHwnd != 0 && (IntPtr)oldHwnd != hwnd)
            GameUnfocus((IntPtr)oldHwnd);
            
        if (IsGameWindow(hwnd))
            GameFocus(hwnd);
	}
	
	private static void GameFocus(IntPtr hwnd)
	{
		// adjust window style
		var wndStyle = BFS.Window.GetWindowStyle(hwnd);
        var newStyle = wndStyle & ~(
            BFS.WindowEnum.WindowStyle.WS_CAPTION | 
            BFS.WindowEnum.WindowStyle.WS_SYSMENU |
            BFS.WindowEnum.WindowStyle.WS_THICKFRAME__SIZEBOX |
            BFS.WindowEnum.WindowStyle.WS_MINIMIZEBOX |
            BFS.WindowEnum.WindowStyle.WS_MAXIMIZEBOX
        );
        if (wndStyle != newStyle)
            BFS.Window.SetWindowStyle(newStyle, hwnd);
		
		// get primary screen
		// DON'T FORGET to set [Advanced Settings] > [Monitor Configuration] > [Force Primary Monitor ID]
		// to   {monitor_id}.{split_id}   if you want a specific split to act as the primary
		var bnds = BFS.Monitor.GetPrimaryMonitorBounds();
		
		int posFlags = 0;
		if (BFS.Window.HasWindowStyleEx(BFS.WindowEnum.WindowStyleEx.WS_EX_TOPMOST, hwnd))
            posFlags |= SWP_NOZORDER;
        var wndBnds = BFS.Window.GetBounds(hwnd);
        if (wndBnds.X == bnds.X && wndBnds.Y == bnds.Y)
            posFlags |= SWP_NOMOVE;
        if (wndBnds.Width == bnds.Width && wndBnds.Height == bnds.Height)
            posFlags |= SWP_NOSIZE;
		
		// we use win32 command directly because BFS.Window.SetSize doesn't seem to work properly with the above window styles
		// plus it's a bit cleaner (less screen flashing) to do everything in one function call
		if (SetWindowPos(hwnd, HWND_TOPMOST, bnds.X, bnds.Y, bnds.Width, bnds.Height, posFlags))
		
            // save it to allow unfocusing later
            BFS.ScriptSettings.WriteValue("GameWindowFocus", hwnd.ToString());
	}
	
	private static void GameUnfocus(IntPtr hwnd)
	{
		int posFlags = SWP_NOMOVE | SWP_NOSIZE;
		if (!BFS.Window.HasWindowStyleEx(BFS.WindowEnum.WindowStyleEx.WS_EX_TOPMOST, hwnd))
            posFlags |= SWP_NOZORDER;
		
		SetWindowPos(hwnd, HWND_NOTOPMOST, 0, 0, 0, 0, posFlags);
		
		// clear save
		BFS.ScriptSettings.WriteValue("GameWindowFocus", null);
	}
	
    [DllImport("user32.dll")]
    static extern bool SetWindowPos(IntPtr hWnd, int hWndInsertAfter, int x, int y, int cx, int cy, int wFlags);
    
    const int HWND_TOPMOST = -1;
    const int HWND_NOTOPMOST = -2;
    
    const int SWP_NOMOVE = 0X2;
    const int SWP_NOSIZE = 1;
    const int SWP_NOZORDER = 0X4;
    const int SWP_SHOWWINDOW = 0x0040;
}