#region Copyright & License Information
/*
 * Copyright 2007-2017 The OpenRA Developers (see AUTHORS)
 * This file is part of OpenRA, which is free software. It is made
 * available to you under the terms of the GNU General Public License
 * as published by the Free Software Foundation, either version 3 of
 * the License, or (at your option) any later version. For more
 * information, see COPYING.
 */
#endregion

using System;
using System.Diagnostics;
using System.Drawing;
using System.IO;
using System.Linq;
using System.Media;
using System.Reflection;
using System.Runtime.InteropServices;
using System.Windows.Forms;

namespace OpenRA
{
	class WindowsLauncher
	{
		[DllImport("user32.dll")]
		static extern int SendMessage(IntPtr hwnd, uint message, uint wParam, IntPtr lParam);

		[DllImport("shell32.dll")]
		static extern IntPtr SHGetFileInfo(string pszPath, uint dwFileAttributes, ref SHFILEINFO psfi, uint cbSizeFileInfo, uint uFlags);

		[DllImport("user32.dll")]
		public extern static bool DestroyIcon(IntPtr handle);

		struct SHFILEINFO
		{
			// Native type: HICON
			public IntPtr hIcon;

			public int iIcon;
			public uint dwAttributes;

			// Native type: TCHAR[MAX_PATH]
			[MarshalAs(UnmanagedType.ByValTStr, SizeConst = 260)]

			public string szDisplayName;

			// Native type: TCHAR[80]
			[MarshalAs(UnmanagedType.ByValTStr, SizeConst = 80)]

			public string szTypeName;
		}

		static Process gameProcess;

		// Constants to be replaced by the wrapper / compilation script
		const string ModID = "MOD_ID";
		const string DisplayName = "DISPLAY_NAME";
		const string FaqUrl = "FAQ_URL";

		// References to the OpenRA.Game.exe icons for later cleanup
		static IntPtr[] iconHandle = { IntPtr.Zero, IntPtr.Zero };

		[STAThread]
		static void Main(string[] args)
		{
			var launcherPath = Assembly.GetExecutingAssembly().Location;
			var directory = Path.GetDirectoryName(launcherPath);
			var enginePath = Path.Combine(directory, "OpenRA.Game.exe");

			Directory.SetCurrentDirectory(directory);

			if (!string.IsNullOrEmpty(ModID))
				args = args.Append("Game.Mod=" + ModID).ToArray();

			var engineArgs = args
				.Append("Engine.LaunchPath=" + launcherPath)
				.Select(arg => "\"" + arg + "\"");

			var psi = new ProcessStartInfo(enginePath, string.Join(" ", engineArgs));

			try
			{
				gameProcess = Process.Start(psi);
			}
			catch
			{
				return;
			}

			if (gameProcess == null)
				return;

			if (Platform.CurrentPlatform == PlatformType.Windows)
			{
				// Set the OpenRA.Game.exe icon to match the mod
				// Icon.ExtractAssociatedIcon sets only the 32px icon,
				// so we use native functions to set both 16 and 32px versions.
				gameProcess.WaitForInputIdle();
				SHFILEINFO sfi = new SHFILEINFO();
				for (var i = 0; i < 2; i++)
				{
					SHGetFileInfo(Assembly.GetExecutingAssembly().Location, 0, ref sfi, (uint)Marshal.SizeOf(sfi), (uint)(0x100 + i));
					iconHandle[i] = sfi.hIcon;
					SendMessage(gameProcess.MainWindowHandle, 0x80, (uint)(1 - i), sfi.hIcon);
				}
			}

			gameProcess.EnableRaisingEvents = true;
			gameProcess.Exited += GameProcessExited;

			Application.Run();
		}

		static void ShowErrorDialog()
		{
			var headerLabel = new Label
			{
				Location = new Point(0, 10),
				Height = 15,
				Text = DisplayName + " has encountered a fatal error and must close.",
				TextAlign = ContentAlignment.TopCenter
			};

			var docsLabel = new Label
			{
				Location = new Point(0, 25),
				Height = 15,
				Text = "Refer to the crash logs and FAQ for more information.",
				TextAlign = ContentAlignment.TopCenter
			};

			int formWidth;
			using (var g = headerLabel.CreateGraphics())
			{
				var headerWidth = (int)g.MeasureString(headerLabel.Text, headerLabel.Font).Width + 60;
				var docsWidth = (int)g.MeasureString(docsLabel.Text, docsLabel.Font).Width + 60;
				formWidth = Math.Max(headerWidth, docsWidth);
				headerLabel.Width = formWidth;
				docsLabel.Width = formWidth;
			}

			var form = new Form
			{
				Size = new Size(formWidth, 110),
				Text = "Fatal Error",
				MinimizeBox = false,
				MaximizeBox = false,
				FormBorderStyle = FormBorderStyle.FixedDialog,
				StartPosition = FormStartPosition.CenterScreen,
				TopLevel = true,
				Icon = Icon.ExtractAssociatedIcon(Assembly.GetExecutingAssembly().Location)
			};

			var viewLogs = new Button
			{
				Location = new Point(10, 50),
				Size = new Size(75, 23),
				Text = "View Logs"
			};

			var viewFaq = new Button
			{
				Location = new Point(90, 50),
				Size = new Size(75, 23),
				Text = "View FAQ"
			};

			var quit = new Button
			{
				Location = new Point(formWidth - 90, 50),
				Size = new Size(75, 23),
				Text = "Quit",
				DialogResult = DialogResult.Cancel
			};

			form.Controls.Add(headerLabel);
			form.Controls.Add(docsLabel);
			form.Controls.Add(viewLogs);
			form.Controls.Add(viewFaq);
			form.Controls.Add(quit);

			viewLogs.Click += ViewLogsClicked;
			viewFaq.Click += ViewFaqClicked;
			form.FormClosed += FormClosed;

			SystemSounds.Exclamation.Play();
			form.ShowDialog();
		}

		static void GameProcessExited(object sender, EventArgs e)
		{
			if (gameProcess.ExitCode != (int)RunStatus.Success)
				ShowErrorDialog();

			if (Platform.CurrentPlatform == PlatformType.Windows)
				foreach (var handle in iconHandle)
					if (handle != IntPtr.Zero)
						DestroyIcon(handle);

			Exit();
		}

		static void ViewLogsClicked(object sender, EventArgs e)
		{
			try
			{
				Process.Start(Platform.ResolvePath("^", "Logs"));
			}
			catch { }
		}

		static void ViewFaqClicked(object sender, EventArgs e)
		{
			try
			{
				Process.Start(FaqUrl);
			}
			catch { }
		}

		static void FormClosed(object sender, EventArgs e)
		{
			Exit();
		}

		static void Exit()
		{
			Environment.Exit(0);
		}
	}
}