// Copyright 1998-2015 Epic Games, Inc. All Rights Reserved.

using System;
using System.Collections.Generic;
using System.IO;
using System.Xml;
using System.Xml.XPath;
using System.Xml.Linq;
using System.Linq;
using System.Text;

namespace UnrealBuildTool
{
	public interface IntelliSenseGatherer
	{
		/// <summary>
		/// Adds all of the specified preprocessor definitions to this VCProject's list of preprocessor definitions for all modules in the project
		/// </summary>
		/// <param name="NewPreprocessorDefinitions">List of preprocessor definitons to add</param>
		void AddIntelliSensePreprocessorDefinitions( List<string> NewPreprocessorDefinitions );

		/// <summary>
		/// Adds all of the specified include paths to this VCProject's list of include paths for all modules in the project
		/// </summary>
		/// <param name="NewIncludePaths">List of include paths to add</param>
		/// <param name="bAddingSystemIncludes">Are the include paths to add system include paths</param>
		void AddInteliiSenseIncludePaths(HashSet<string> NewIncludePaths, bool bAddingSystemIncludes);
	}


	/// <summary>
	/// A single target within a project.  A project may have any number of targets within it, which are basically compilable projects
	/// in themselves that the project wraps up.
	/// </summary>
	public class ProjectTarget
	{
		/// The target rules file path on disk, if we have one
		public string TargetFilePath;

		/// Optional target rules for this target.  If the target came from a *.Target.cs file on disk, then it will have one of these.
		/// For targets that are synthetic (like UnrealBuildTool or other manually added project files) we won't have a rules object for those.
		public TargetRules TargetRules;

		/// Extra supported build platforms.  Normally the target rules determines these, but for synthetic targets we'll add them here.
		public List<UnrealTargetPlatform> ExtraSupportedPlatforms = new List<UnrealTargetPlatform>();

		/// Extra supported build configurations.  Normally the target rules determines these, but for synthetic targets we'll add them here.
		public List<UnrealTargetConfiguration> ExtraSupportedConfigurations = new List<UnrealTargetConfiguration>();

		/// If true, forces Development configuration regardless of which configuration is set as the Solution Configuration
		public bool ForceDevelopmentConfiguration = false;

		/// Whether the project requires 'Deploy' option set (VC projects)
		public bool ProjectDeploys = false;

		public override string ToString()
		{
			return Path.GetFileNameWithoutExtension(TargetFilePath);
		}
	}

	/// <summary>
	/// Class that stores info about aliased file.
	/// </summary>
	public class AliasedFile
	{
		public AliasedFile(string FileSystemPath, string ProjectPath)
		{
			this.FileSystemPath = FileSystemPath;
			this.ProjectPath = ProjectPath;
		}

		// File system path.
		public string FileSystemPath { get; private set; }

		// Project path.
		public string ProjectPath { get; private set; }
	}

	public abstract class ProjectFile : IntelliSenseGatherer
	{
		/// <summary>
		/// Represents a single source file (or other type of file) in a project
		/// </summary>
		public class SourceFile
		{
			/// <summary>
			/// Constructor
			/// </summary>
			/// <param name="InitFilePath">Path to the source file on disk</param>
			/// <param name="InitRelativeBaseFolder">The directory on this the path within the project will be relative to</param>
			public SourceFile( string InitFilePath, string InitRelativeBaseFolder )
			{
				FilePath = InitFilePath;
				RelativeBaseFolder = InitRelativeBaseFolder;
			}

			public SourceFile()
			{
			}

			/// <summary>
			/// File path to file on disk
			/// </summary>
			public string FilePath
			{
				get;
				private set;
			}

			/// <summary>
			/// Optional directory that overrides where files in this project are relative to when displayed in the IDE.  If null, will default to the project's RelativeBaseFolder.
			/// </summary>
			public string RelativeBaseFolder
			{
				get;
				private set;
			}
		}


		/// <summary>
		/// Constructs a new project file object
		/// </summary>
		/// <param name="InitFilePath">The path to the project file, relative to the master project file</param>
		protected ProjectFile( string InitRelativeFilePath )
		{
			RelativeProjectFilePath = InitRelativeFilePath;
			ShouldBuildByDefaultForSolutionTargets = true;
		}


		/// Full path to the project file on disk
		public string ProjectFilePath
		{
			get
			{
				return Path.Combine( ProjectFileGenerator.MasterProjectRelativePath, RelativeProjectFilePath );
			}
		}


		/// Project file path, relative to the master project
		public string RelativeProjectFilePath
		{
			get;
			private set;
		}

	
		/// Returns true if this is a generated project (as opposed to an imported project)
		public bool IsGeneratedProject
		{
			get;
			set;
		}


		/// Returns true if this is a "stub" project.  Stub projects function as dumb containers for source files
		/// and are never actually "built" by the master project.  Stub projects are always "generated" projects.
		public bool IsStubProject
		{
			get;
			set;
		}

		/// Returns true if this is a foreign project, and requires UBT to be passed the path to the .uproject file 
		/// on the command line.
		public bool IsForeignProject
		{
			get;
			set;
		}

		/// Whether this project should be built for all solution targets
		public bool ShouldBuildForAllSolutionTargets
		{
			get;
			set;
		}

		/// Whether this project should be built by default. Can still be built from the IDE through the context menu.
		public bool ShouldBuildByDefaultForSolutionTargets
		{
			get;
			set;
		}



		/// All of the targets in this project.  All non-stub projects must have at least one target.
		public readonly List<ProjectTarget> ProjectTargets = new List<ProjectTarget>();



		/// <summary>
		/// Adds a list of files to this project, ignoring dupes
		/// </summary>
		/// <param name="FilesToAdd">Files to add</param>
		/// <param name="RelativeBaseFolder">The directory the path within the project will be relative to</param>
		public void AddFilesToProject( List<string> FilesToAdd, string RelativeBaseFolder )
		{
			foreach( var CurFile in FilesToAdd )
			{
				AddFileToProject( CurFile, RelativeBaseFolder );
			}
		}

		/// Aliased (i.e. files is custom filter tree) in this project
		public readonly List<AliasedFile> AliasedFiles = new List<AliasedFile>();

		/// <summary>
		/// Adds aliased file to the project.
		/// </summary>
		/// <param name="File">Aliased file.</param>
		public void AddAliasedFileToProject(AliasedFile File)
		{
			AliasedFiles.Add(File);
		}
	
		/// <summary>
		/// Adds a file to this project, ignoring dupes
		/// </summary>
		/// <param name="FilePath">Path to the file on disk</param>
		/// <param name="RelativeBaseFolder">The directory the path within the project will be relative to</param>
		public void AddFileToProject( string FilePath, string RelativeBaseFolder )
		{
			// Don't add duplicates
			SourceFile ExistingFile = null;
            if (SourceFileMap.TryGetValue(FilePath, out ExistingFile))
            {
                if( ExistingFile.RelativeBaseFolder != RelativeBaseFolder )
                {
                    if( ( ExistingFile.RelativeBaseFolder != null ) != ( RelativeBaseFolder != null ) ||
                        !ExistingFile.RelativeBaseFolder.Equals( RelativeBaseFolder, StringComparison.InvariantCultureIgnoreCase ) )
                    {
                        throw new BuildException( "Trying to add file '" + FilePath + "' to project '" + ProjectFilePath + "' when the file already exists, but with a different relative base folder '" + RelativeBaseFolder + "' is different than the current file's '" + ExistingFile.RelativeBaseFolder + "'!" );
                    }
                    else
                    {
                        throw new BuildException( "Trying to add file '" + FilePath + "' to project '" + ProjectFilePath + "' when the file already exists, but the specified project relative base folder is different than the current file's!" );
                    }
                }
			}
			else
			{
				SourceFile File = AllocSourceFile( FilePath, RelativeBaseFolder );
				if( File != null )
				{
					SourceFileMap[FilePath] = File;
					SourceFiles.Add( File );
				}
			}
		}

		/// <summary>
		/// Splits the definition text into macro name and value (if any).
		/// </summary>
		/// <param name="Definition">Definition text</param>
		/// <param name="Key">Out: The definition name</param>
		/// <param name="Value">Out: The definition value or null if it has none</param>
		/// <returns>Pair representing macro name and value.</returns>
		private void SplitDefinitionAndValue(string Definition, out String Key, out String Value)
		{
			int EqualsIndex = Definition.IndexOf('=');
			if (EqualsIndex >= 0)
			{
				Key = Definition.Substring(0, EqualsIndex);
				Value = Definition.Substring(EqualsIndex + 1);
			}
			else
			{
				Key = Definition;
				Value = "";
			}
		}

		/// <summary>
		/// Adds all of the specified preprocessor definitions to this VCProject's list of preprocessor definitions for all modules in the project
		/// </summary>
		/// <param name="NewPreprocessorDefinitions">List of preprocessor definitons to add</param>
		public void AddIntelliSensePreprocessorDefinitions( List<string> NewPreprocessorDefinitions ) 
		{
			if( ProjectFileGenerator.OnlyGenerateIntelliSenseDataForProject == null || 
				ProjectFileGenerator.OnlyGenerateIntelliSenseDataForProject == this )
			{ 
				foreach( var CurDef in NewPreprocessorDefinitions )
				{
					// Don't add definitions and value combinations that have already been added for this project
					if( KnownIntelliSensePreprocessorDefinitions.Add( CurDef ) )
					{
						// Go ahead and check to see if the definition already exists, but the value is different
						var AlreadyExists = false;

						string Def, Value;
						SplitDefinitionAndValue(CurDef, out Def, out Value);
						for (int DefineIndex = 0; DefineIndex < IntelliSensePreprocessorDefinitions.Count; ++DefineIndex)
						{
							string ExistingDef, ExistingValue;
							SplitDefinitionAndValue(IntelliSensePreprocessorDefinitions[DefineIndex], out ExistingDef, out ExistingValue);
							if (ExistingDef == Def)
							{
								// Already exists, but the value is changing.  We don't bother clobbering values for existing defines for this project.
								AlreadyExists = true;
								break;
							}
						}

						if( !AlreadyExists )
						{
							IntelliSensePreprocessorDefinitions.Add( CurDef );
						}
					}
				}
			}
		}


		/// <summary>
		/// Adds all of the specified include paths to this VCProject's list of include paths for all modules in the project
		/// </summary>
		/// <param name="NewIncludePaths">List of include paths to add</param>
		public void AddInteliiSenseIncludePaths(HashSet<string> NewIncludePaths, bool bAddingSystemIncludes) 
		{
			if( ProjectFileGenerator.OnlyGenerateIntelliSenseDataForProject == null || 
				ProjectFileGenerator.OnlyGenerateIntelliSenseDataForProject == this )
			{ 
				foreach( var CurPath in NewIncludePaths )
				{
					if( bAddingSystemIncludes ? KnownIntelliSenseSystemIncludeSearchPaths.Add( CurPath ) : KnownIntelliSenseIncludeSearchPaths.Add( CurPath ) )
					{
						string PathRelativeToProjectFile;

						// If the include string is an environment variable (e.g. $(DXSDK_DIR)), then we never want to
						// give it a relative path
						if( CurPath.StartsWith( "$(" ) )
						{
							PathRelativeToProjectFile = CurPath;
						}
						else
						{
							// Incoming include paths are relative to the solution directory, but we need these paths to be
							// relative to the project file's directory
							PathRelativeToProjectFile = NormalizeProjectPath( CurPath );
						}

						// Trim any trailing slash
						PathRelativeToProjectFile = PathRelativeToProjectFile.TrimEnd('/', '\\');

						// Make sure that it doesn't exist already
						var AlreadyExists = false;
						List<string> SearchPaths = bAddingSystemIncludes ? IntelliSenseSystemIncludeSearchPaths : IntelliSenseIncludeSearchPaths;
						foreach( var ExistingPath in SearchPaths )
						{
							if( PathRelativeToProjectFile == ExistingPath )
							{
								AlreadyExists = true;
								break;
							}
						}

						if( !AlreadyExists )
						{
							SearchPaths.Add( PathRelativeToProjectFile );
						}
					}
				}
			}
		}

		/// <summary>
		/// Add the given project to the DepondsOn project list.
		/// </summary>
		/// <param name="InProjectFile">The project this project is dependent on</param>
		public void AddDependsOnProject(ProjectFile InProjectFile)
		{
			// Make sure that it doesn't exist already
			var AlreadyExists = false;
			foreach (var ExistingDependentOn in DependsOnProjects)
			{
				if (ExistingDependentOn == InProjectFile)
				{
					AlreadyExists = true;
					break;
				}
			}

			if (AlreadyExists == false)
			{
				DependsOnProjects.Add(InProjectFile);
			}
		}

		/// <summary>
		/// Writes a project file to disk
		/// </summary>
		/// <param name="InPlatforms">The platforms to write the project files for</param>
		/// <param name="InConfigurations">The configurations to add to the project files</param>
		/// <returns>True on success</returns>
		public virtual bool WriteProjectFile(List<UnrealTargetPlatform> InPlatforms, List<UnrealTargetConfiguration> InConfigurations)
		{
			throw new BuildException( "UnrealBuildTool cannot automatically generate this project type because WriteProjectFile() was not overridden." );
		}

		public virtual void LoadGUIDFromExistingProject()
		{
		}

		/// <summary>
		/// Allocates a generator-specific source file object
		/// </summary>
		/// <param name="InitFilePath">Path to the source file on disk</param>
		/// <param name="InitProjectSubFolder">Optional sub-folder to put the file in.  If empty, this will be determined automatically from the file's path relative to the project file</param>
		/// <returns>The newly allocated source file object</returns>
		public virtual SourceFile AllocSourceFile( string InitFilePath, string InitProjectSubFolder = null )
		{
			return new SourceFile( InitFilePath, InitProjectSubFolder );
		}

		/** Takes the given path and tries to rebase it relative to the project or solution directory variables. */
		public string NormalizeProjectPath(string InputPath)
		{
			// If the path is rooted in an environment variable, leave it be.
			if(InputPath.StartsWith("$("))
			{
				return InputPath;
			}

			// Otherwise make sure it's absolute
			string FullInputPath = Utils.CleanDirectorySeparators(Path.GetFullPath(InputPath));

			// Try to make it relative to the solution directory.
			string FullSolutionPath = Utils.CleanDirectorySeparators(Path.GetFullPath(ProjectFileGenerator.MasterProjectRelativePath));
			if (FullSolutionPath.Last() != Path.DirectorySeparatorChar)
			{
				FullSolutionPath += Path.DirectorySeparatorChar;
			}
			if (FullInputPath.StartsWith(FullSolutionPath))
			{
				FullInputPath = Utils.MakePathRelativeTo(Utils.CleanDirectorySeparators(FullInputPath), Path.GetDirectoryName(Path.GetFullPath(ProjectFilePath)));
			}
			else
			{
				FullInputPath = Utils.CleanDirectorySeparators(FullInputPath);
			}

			// Otherwise return the input
			return FullInputPath;
		}

		/** Takes the given path, normalizes it, and quotes it if necessary. */
		public string EscapePath(string InputPath)
		{
			string Result = InputPath;
			if (Result.Contains(' '))
			{
				Result = "\"" + Result + "\"";
			}
			return Result;
		}

		/** Visualizer for the debugger */
		public override string ToString()
		{
			return RelativeProjectFilePath;
		}

		/// Map of file paths to files in the project.
        private readonly Dictionary<string, SourceFile> SourceFileMap = new Dictionary<string, SourceFile>(StringComparer.InvariantCultureIgnoreCase);

		/// Files in this project
		public readonly List<SourceFile> SourceFiles = new List<SourceFile>();

		/// Include paths for every single module in the project file, merged together
		public readonly List<string> IntelliSenseIncludeSearchPaths = new List<string>();
		public readonly List<string> IntelliSenseSystemIncludeSearchPaths = new List<string>();
		public readonly HashSet<string> KnownIntelliSenseIncludeSearchPaths = new HashSet<string>( StringComparer.InvariantCultureIgnoreCase );
		public readonly HashSet<string> KnownIntelliSenseSystemIncludeSearchPaths = new HashSet<string>( StringComparer.InvariantCultureIgnoreCase );

		/// Preprocessor definitions for every single module in the project file, merged together
		public readonly List<string> IntelliSensePreprocessorDefinitions = new List<string>();
		public readonly HashSet<string> KnownIntelliSensePreprocessorDefinitions = new HashSet<string>( StringComparer.InvariantCultureIgnoreCase );

		/// Projects that this project is dependent on
		public readonly List<ProjectFile> DependsOnProjects = new List<ProjectFile>();
	}

}