// Copyright Epic Games, Inc. All Rights Reserved.

using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Reflection;
using System.Text;
using System.Threading.Tasks;
using EpicGames.Core;
using System.Diagnostics;
using UnrealBuildBase;
using System.Diagnostics.CodeAnalysis;

namespace UnrealBuildTool
{
	/// <summary>
	/// Generates project files for one or more projects
	/// </summary>
	[ToolMode("GenerateProjectFiles", ToolModeOptions.XmlConfig | ToolModeOptions.BuildPlatforms | ToolModeOptions.SingleInstance | ToolModeOptions.UseStartupTraceListener)]
	class GenerateProjectFilesMode : ToolMode
	{
		/// <summary>
		/// Types of project files to generate
		/// </summary>
		[CommandLine("-ProjectFileFormat")]
		[CommandLine("-2019", Value = nameof(ProjectFileFormat.VisualStudio2019))] // + override compiler
		[CommandLine("-2022", Value = nameof(ProjectFileFormat.VisualStudio2022))] // + override compiler
		[CommandLine("-Makefile", Value = nameof(ProjectFileFormat.Make))]
		[CommandLine("-CMakefile", Value = nameof(ProjectFileFormat.CMake))]
		[CommandLine("-QMakefile", Value = nameof(ProjectFileFormat.QMake))]
		[CommandLine("-KDevelopfile", Value = nameof(ProjectFileFormat.KDevelop))]
		[CommandLine("-CodeLiteFiles", Value = nameof(ProjectFileFormat.CodeLite))]
		[CommandLine("-XCodeProjectFiles", Value = nameof(ProjectFileFormat.XCode))]
		[CommandLine("-EddieProjectFiles", Value = nameof(ProjectFileFormat.Eddie))]
		[CommandLine("-VSCode", Value = nameof(ProjectFileFormat.VisualStudioCode))]
		[CommandLine("-VSMac", Value = nameof(ProjectFileFormat.VisualStudioMac))]
		[CommandLine("-CLion", Value = nameof(ProjectFileFormat.CLion))]
		[CommandLine("-Rider", Value = nameof(ProjectFileFormat.Rider))]
		#if __VPROJECT_AVAILABLE__
			[CommandLine("-VProject", Value = nameof(ProjectFileFormat.VProject))]
		#endif
		HashSet<ProjectFileFormat> ProjectFileFormats = new HashSet<ProjectFileFormat>();

		/// <summary>
		/// Disable native project file generators for platforms. Platforms with native project file generators typically require IDE extensions to be installed.
		/// </summary>
		[XmlConfigFile(Category = "ProjectFileGenerator")]
		string[]? DisablePlatformProjectGenerators = null;

		/// <summary>
		/// Whether this command is being run in an automated mode
		/// </summary>
		[CommandLine("-Automated")]
		bool bAutomated = false;

		/// <summary>
		/// Execute the tool mode
		/// </summary>
		/// <param name="Arguments">Command line arguments</param>
		/// <returns>Exit code</returns>
		public override int Execute(CommandLineArguments Arguments)
		{
			// Apply any command line arguments to this class
			Arguments.ApplyTo(this);

			// Apply the XML config to this class
			XmlConfig.ApplyTo(this);

			// set up logging (taken from BuildMode)
			FileReference LogFile = FileReference.Combine(UnrealBuildTool.EngineProgramSavedDirectory, "UnrealBuildTool", "Log_GPF.txt");
			Log.AddFileWriter("DefaultLogTraceListener", LogFile);

			// Parse rocket-specific arguments.
			FileReference? ProjectFile;
			TryParseProjectFileArgument(Arguments, out ProjectFile);

			// Warn if there are explicit project file formats specified
			if (ProjectFileFormats.Count > 0 && !bAutomated)
			{
				StringBuilder Configuration = new StringBuilder();
				Configuration.Append("Project file formats specified via the command line will be ignored when generating\n");
				Configuration.Append("project files from the editor and other engine tools.\n");
				Configuration.Append("\n");
				Configuration.Append("Consider setting your desired IDE from the editor preferences window, or modify your\n");
				Configuration.Append("BuildConfiguration.xml file with:\n");
				Configuration.Append("\n");
				Configuration.Append("<?xml version=\"1.0\" encoding=\"utf-8\" ?>\n");
				Configuration.Append("<Configuration xmlns=\"https://www.unrealengine.com/BuildConfiguration\">\n");
				Configuration.Append("  <ProjectFileGenerator>\n");
				foreach(ProjectFileFormat ProjectFileFormat in ProjectFileFormats)
				{
					Configuration.AppendFormat("    <Format>{0}</Format>\n", ProjectFileFormat);
				}
				Configuration.Append("  </ProjectFileGenerator>\n");
				Configuration.Append("</Configuration>\n");
				Log.TraceWarning("{0}", Configuration.ToString());
			}

			// If there aren't any formats set, read the default project file format from the config file
			if (ProjectFileFormats.Count == 0)
			{
				// Read from the XML config
				if (!String.IsNullOrEmpty(ProjectFileGeneratorSettings.Format))
				{
					ProjectFileFormats.UnionWith(ProjectFileGeneratorSettings.ParseFormatList(ProjectFileGeneratorSettings.Format));
				}

				// Read from the editor config
				ProjectFileFormat PreferredSourceCodeAccessor;
				if (ProjectFileGenerator.GetPreferredSourceCodeAccessor(ProjectFile, out PreferredSourceCodeAccessor))
				{
					ProjectFileFormats.Add(PreferredSourceCodeAccessor);
				}

				// If there's still nothing set, get the default project file format for this platform
				if (ProjectFileFormats.Count == 0)
				{
					ProjectFileFormats.UnionWith(BuildHostPlatform.Current.GetDefaultProjectFileFormats());
				}
			}

			// Register all the platform project generators
			PlatformProjectGeneratorCollection PlatformProjectGenerators = new PlatformProjectGeneratorCollection();
			foreach (Type CheckType in Assembly.GetExecutingAssembly().GetTypes())
			{
				if (CheckType.IsClass && !CheckType.IsAbstract && CheckType.IsSubclassOf(typeof(PlatformProjectGenerator)))
				{
					PlatformProjectGenerator Generator = (PlatformProjectGenerator)Activator.CreateInstance(CheckType, Arguments)!;
					foreach(UnrealTargetPlatform Platform in Generator.GetPlatforms())
					{
						if(DisablePlatformProjectGenerators == null || !DisablePlatformProjectGenerators.Any(x => x.Equals(Platform.ToString(), StringComparison.OrdinalIgnoreCase)))
						{
							Log.TraceVerbose("Registering project generator {0} for {1}", CheckType, Platform);
							PlatformProjectGenerators.RegisterPlatformProjectGenerator(Platform, Generator);
						}
					}
				}
			}

			// print out any errors to the log
			List<string> BadPlatformNames = new List<string>();
			Log.TraceLog("\n---   SDK INFO START   ---");
			foreach (string PlatformName in UnrealTargetPlatform.GetValidPlatformNames())
			{
				UEBuildPlatformSDK? SDK = UEBuildPlatformSDK.GetSDKForPlatform(PlatformName);
				if (SDK != null && SDK.bIsSdkAllowedOnHost)
				{
					// print out the info to the log, and if it's invalid, remember it
					SDKStatus Validity = SDK.PrintSDKInfoAndReturnValidity(LogEventType.Verbose, LogFormatOptions.NoConsoleOutput, LogEventType.Warning, LogFormatOptions.NoConsoleOutput);
					if (Validity == SDKStatus.Invalid)
					{
						BadPlatformNames.Add(PlatformName);
					}
				}
			}
			if (BadPlatformNames.Count > 0)
			{
				Log.TraceInformationOnce("\nSome Platforms were skipped due to invalid SDK setup: {0}.\nSee the log file for detailed information\n\n", string.Join(", ", BadPlatformNames));
				Log.TraceInformation("");
			}
			Log.TraceLog("---   SDK INFO END   ---");
			Log.TraceLog("");

			// Create each project generator and run it
			List<ProjectFileGenerator> Generators = new List<ProjectFileGenerator>();
			foreach (ProjectFileFormat ProjectFileFormat in ProjectFileFormats.Distinct())
			{
				ProjectFileGenerator Generator;
				switch (ProjectFileFormat)
				{
					case ProjectFileFormat.Make:
						Generator = new MakefileGenerator(ProjectFile);
						break;
					case ProjectFileFormat.CMake:
						Generator = new CMakefileGenerator(ProjectFile);
						break;
					case ProjectFileFormat.QMake:
						Generator = new QMakefileGenerator(ProjectFile);
						break;
					case ProjectFileFormat.KDevelop:
						Generator = new KDevelopGenerator(ProjectFile);
						break;
					case ProjectFileFormat.CodeLite:
						Generator = new CodeLiteGenerator(ProjectFile, Arguments);
						break;
					case ProjectFileFormat.VisualStudio:
						Generator = new VCProjectFileGenerator(ProjectFile, VCProjectFileFormat.Default, Arguments);
						break;
					case ProjectFileFormat.VisualStudio2019:
						Generator = new VCProjectFileGenerator(ProjectFile, VCProjectFileFormat.VisualStudio2019, Arguments);
						break;
					case ProjectFileFormat.VisualStudio2022:
						Generator = new VCProjectFileGenerator(ProjectFile, VCProjectFileFormat.VisualStudio2022, Arguments);
						break;
					case ProjectFileFormat.XCode:
						Generator = new XcodeProjectFileGenerator(ProjectFile, Arguments);
						break;
					case ProjectFileFormat.Eddie:
						Generator = new EddieProjectFileGenerator(ProjectFile);
						break;
					case ProjectFileFormat.VisualStudioCode:
						Generator = new VSCodeProjectFileGenerator(ProjectFile);
						break;
					case ProjectFileFormat.CLion:
						Generator = new CLionGenerator(ProjectFile);
						break;
					case ProjectFileFormat.VisualStudioMac:
						Generator = new VCMacProjectFileGenerator(ProjectFile, Arguments);
						break;
					case ProjectFileFormat.Rider:
						Generator = new RiderProjectFileGenerator(ProjectFile, Arguments);
						break;
					#if __VPROJECT_AVAILABLE__
						case ProjectFileFormat.VProject:
							Generator = new VProjectFileGenerator(ProjectFile);
							break;
					#endif
					default:
						throw new BuildException("Unhandled project file type '{0}", ProjectFileFormat);
				}
				Generators.Add(Generator);
			}

			// Check there are no superfluous command line arguments
			// TODO (still pass raw arguments below)
			// Arguments.CheckAllArgumentsUsed();

			// Now generate project files
			ProjectFileGenerator.bGenerateProjectFiles = true;
			foreach(ProjectFileGenerator Generator in Generators)
			{
				ProjectFileGenerator.Current = Generator;
				bool bGenerateSuccess = Generator.GenerateProjectFiles(PlatformProjectGenerators, Arguments.GetRawArray());
				ProjectFileGenerator.Current = null;

				if (!bGenerateSuccess)
				{
					return (int)CompilationResult.OtherCompilationError;
				}
			}
			return (int)CompilationResult.Succeeded;
		}

		/// <summary>
		/// Try to parse the project file from the command line
		/// </summary>
		/// <param name="Arguments">The command line arguments</param>
		/// <param name="ProjectFile">The project file that was parsed</param>
		/// <returns>True if the project file was parsed, false otherwise</returns>
		private static bool TryParseProjectFileArgument(CommandLineArguments Arguments, [NotNullWhen(true)] out FileReference? ProjectFile)
		{
			string? CandidateProjectPath = null;

			// look for -project=<path>, if it does not exist check arguments for anything that has .uproject in it
			if (!Arguments.TryGetValue("-Project=", out CandidateProjectPath))
			{
				// Go through the argument list and try to match poorly (or well..) formed arguments like 
				// EngineTest, EngineTest.uproject
				// Collaboration/FooProject
				// by checking for those in the native project list
				for (int Idx = 0; Idx < Arguments.Count; Idx++)
				{
					if (Arguments[Idx][0] != '-' && Arguments[Idx].EndsWith(".uproject", StringComparison.OrdinalIgnoreCase))
					{
						CandidateProjectPath = Arguments[Idx];
						Arguments.MarkAsUsed(Idx);
						break; 
					}
				}
			}

			// We have a project file either via -project= or because there was something called .uproject in the arg list
			// so now validate it
			if (!string.IsNullOrEmpty(CandidateProjectPath))
			{
				FileReference CandidateProjectFile = new FileReference(CandidateProjectPath);

				// if the path doesn't exist then check native paths (ueprojectdirs)
				if (!FileReference.Exists(CandidateProjectFile))
				{
					// clean everything the user provided to just the name and make sure it has the expected extension
					string ProjectName = CandidateProjectFile.ChangeExtension("uproject").GetFileName();

					// check native project paths (uprojectdirs)
					IEnumerable<FileReference> NativeProjectFiles = NativeProjects.EnumerateProjectFiles();

					CandidateProjectFile = NativeProjectFiles.Where(F => F.GetFileName().Equals(ProjectName, StringComparison.InvariantCultureIgnoreCase)).FirstOrDefault();
				}

				if (CandidateProjectFile == null || !FileReference.Exists(CandidateProjectFile))
				{
					// if we didn't find anything then throw an error as the user explicitly provided a uproject
					throw new Exception(string.Format("Unable to find project file based on argument {0}", CandidateProjectPath));
				}

				Log.TraceVerbose("Resolved project argument {0} to {1}", CandidateProjectPath, CandidateProjectFile);
				ProjectFile = CandidateProjectFile;
				return true;
			}
			
			FileReference? InstalledProjectFile = UnrealBuildTool.GetInstalledProjectFile();
			if(InstalledProjectFile != null)
			{
				ProjectFile = InstalledProjectFile;
				return true;
			}

			ProjectFile = null;
			return false;
		}
	}
}