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

using EpicGames.Core;
using Microsoft.Extensions.Logging;
using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Text;
using System.Text.Json;
using System.Threading.Tasks;
using System.Xml;

namespace AutomationTool.Tasks
{
	/// <summary>
	/// Parameters for a <see cref="HordeCreateReportTask"/>.
	/// </summary>
	public class HordeCreateReportTaskParameters
	{
		/// <summary>
		/// Name for the report
		/// </summary>
		[TaskParameter]
		public string Name;

		/// <summary>
		/// Where to display the report
		/// </summary>
		[TaskParameter]
		public string Scope;

		/// <summary>
		/// Where to show the report
		/// </summary>
		[TaskParameter]
		public string Placement;

		/// <summary>
		/// Text to be displayed
		/// </summary>
		[TaskParameter]
		public string Text;
	}

	/// <summary>
	/// Creates a Horde report file, which will be displayed on the dashboard with any job running this task.
	/// </summary>
	[TaskElement("Horde-CreateReport", typeof(HordeCreateReportTaskParameters))]
	public class HordeCreateReportTask : BgTaskImpl
	{
		/// <summary>
		/// Parameters for this task.
		/// </summary>
		HordeCreateReportTaskParameters Parameters;

		/// <summary>
		/// Constructor.
		/// </summary>
		/// <param name="InParameters">Parameters for this task.</param>
		public HordeCreateReportTask(HordeCreateReportTaskParameters InParameters)
		{
			Parameters = InParameters;
		}

		/// <summary>
		/// Execute the task.
		/// </summary>
		/// <param name="Job">Information about the current job.</param>
		/// <param name="BuildProducts">Set of build products produced by this node.</param>
		/// <param name="TagNameToFileSet">Mapping from tag names to the set of files they include.</param>
		public override async Task ExecuteAsync(JobContext Job, HashSet<FileReference> BuildProducts, Dictionary<string, HashSet<FileReference>> TagNameToFileSet)
		{
			FileReference ReportTextFile = FileReference.Combine(new DirectoryReference(CommandUtils.CmdEnv.LogFolder), $"{Parameters.Name}.md");
			await FileReference.WriteAllTextAsync(ReportTextFile, Parameters.Text);

			FileReference ReportJsonFile = FileReference.Combine(new DirectoryReference(CommandUtils.CmdEnv.LogFolder), $"{Parameters.Name}.report.json");
			using (FileStream ReportJsonStream = FileReference.Open(ReportJsonFile, FileMode.Create, FileAccess.Write, FileShare.Read))
			{
				using (Utf8JsonWriter Writer = new Utf8JsonWriter(ReportJsonStream))
				{
					Writer.WriteStartObject();
					Writer.WriteString("scope", Parameters.Scope);
					Writer.WriteString("name", Parameters.Name);
					Writer.WriteString("placement", Parameters.Placement);
					Writer.WriteString("fileName", ReportTextFile.GetFileName());
					Writer.WriteEndObject();
				}
			}

			Logger.LogInformation("Written report to {TextFile} and {JsonFile}: \"{Text}\"", ReportTextFile, ReportJsonFile, Parameters.Text);
		}

		/// <summary>
		/// Output this task out to an XML writer.
		/// </summary>
		public override void Write(XmlWriter Writer)
		{
			Write(Writer, Parameters);
		}

		/// <summary>
		/// Find all the tags which are used as inputs to this task
		/// </summary>
		/// <returns>The tag names which are read by this task</returns>
		public override IEnumerable<string> FindConsumedTagNames() => Enumerable.Empty<string>();

		/// <summary>
		/// Find all the tags which are modified by this task
		/// </summary>
		/// <returns>The tag names which are modified by this task</returns>
		public override IEnumerable<string> FindProducedTagNames() => Enumerable.Empty<string>();
	}
}