using System;
using System.IO;
using System.Net;
using System.Text;
using System.Threading;
using JmSetupSheetReceiver.Models;

namespace JmSetupSheetReceiver
{
	/// <summary>
	/// 机明程序单对外提交 — 接收端演示源码（学习 / 联调用）。
	/// <para>
	/// 接收 POST JSON 后用 Newtonsoft.Json 还原为 <see cref="SetupsheetData"/> 强类型对象，
	/// 控制台可 summary / tools / images 等命令查看与操作。
	/// </para>
	/// <para>
	/// 默认：http://127.0.0.1:1234/
	/// 参数：JmSetupSheetReceiver.exe [监听前缀] [--fail] [--pretty]
	/// </para>
	/// </summary>
	internal static class Program
	{
		private static bool _forceFail;
		private static bool _prettyJson;
		private static volatile bool _running = true;

		private static int Main(string[] args)
		{
			string prefix = "http://127.0.0.1:1234/";
			ParseArgs(args, ref prefix);

			string receivedDir = Path.Combine(AppDomain.CurrentDomain.BaseDirectory, "Received");
			Directory.CreateDirectory(receivedDir);

			if (!HttpListener.IsSupported)
			{
				Console.WriteLine("当前系统不支持 HttpListener。");
				return 1;
			}

			var listener = new HttpListener();
			listener.Prefixes.Add(prefix);

			try
			{
				listener.Start();
			}
			catch (HttpListenerException ex)
			{
				Console.WriteLine("无法监听 {0}", prefix);
				Console.WriteLine("原因: {0}", ex.Message);
				Console.WriteLine();
				Console.WriteLine("提示: 非管理员账户监听 localhost 以外地址时，可能需要先执行:");
				Console.WriteLine("  netsh http add urlacl url={0} user=%USERNAME%", prefix);
				return 2;
			}

			PrintBanner(prefix, receivedDir);
			SetupSheetOps.PrintHelp();

			Console.CancelKeyPress += (s, e) =>
			{
				e.Cancel = true;
				_running = false;
				try { listener.Stop(); } catch { }
			};

			// 监听循环放后台，主线程跑命令行，便于操作已还原对象
			var acceptThread = new Thread(() => AcceptLoop(listener, receivedDir))
			{
				IsBackground = true,
				Name = "HttpAccept"
			};
			acceptThread.Start();

			RunCommandLoop(receivedDir);

			_running = false;
			try { listener.Stop(); } catch { }
			try { listener.Close(); } catch { }
			return 0;
		}

		private static void AcceptLoop(HttpListener listener, string receivedDir)
		{
			while (_running && listener.IsListening)
			{
				HttpListenerContext context;
				try
				{
					context = listener.GetContext();
				}
				catch (HttpListenerException)
				{
					break;
				}
				catch (ObjectDisposedException)
				{
					break;
				}

				ThreadPool.QueueUserWorkItem(_ => HandleRequest(context, receivedDir));
			}
		}

		private static void ParseArgs(string[] args, ref string prefix)
		{
			if (args == null) return;
			foreach (string raw in args)
			{
				if (string.IsNullOrWhiteSpace(raw)) continue;
				string a = raw.Trim();
				if (string.Equals(a, "--fail", StringComparison.OrdinalIgnoreCase)
					|| string.Equals(a, "-fail", StringComparison.OrdinalIgnoreCase))
				{
					_forceFail = true;
					continue;
				}
				if (string.Equals(a, "--pretty", StringComparison.OrdinalIgnoreCase)
					|| string.Equals(a, "-pretty", StringComparison.OrdinalIgnoreCase))
				{
					_prettyJson = true;
					continue;
				}
				if (a.StartsWith("-"))
				{
					Console.WriteLine("未知参数: {0}（已忽略）", a);
					continue;
				}
				prefix = a;
				if (!prefix.EndsWith("/")) prefix += "/";
			}
		}

		private static void PrintBanner(string prefix, string receivedDir)
		{
			Console.WriteLine("================================================");
			Console.WriteLine(" 机明程序单接收端演示  JmSetupSheetReceiver");
			Console.WriteLine("================================================");
			Console.WriteLine("监听地址 : {0}", prefix);
			Console.WriteLine("落盘目录 : {0}", receivedDir);
			Console.WriteLine("GET 探活 : 浏览器打开上述地址");
			Console.WriteLine("POST     : JSON → 对象 + 原文/分行JSON/明文落盘 → {0}",
				_forceFail ? "500 (--fail)" : "200");
			Console.WriteLine("落盘文件 : *.json（原文）+ *.pretty.json（分行）+ *.txt（中文明文）");
			if (_prettyJson) Console.WriteLine("提示     : --pretty 已默认等价（还原成功总会写 .pretty.json）");
			Console.WriteLine("明文     : 控制台打印中英对照（预览图仅字节摘要）");
			Console.WriteLine("对象访问 : SetupSheetStore.Latest  / 下方控制台命令");
			Console.WriteLine("按 Ctrl+C 或输入 quit 退出");
			Console.WriteLine("================================================");
			Console.WriteLine();
		}

		private static void RunCommandLoop(string receivedDir)
		{
			while (_running)
			{
				Console.Write("> ");
				string line;
				try
				{
					line = Console.ReadLine();
				}
				catch
				{
					break;
				}
				if (line == null) break;
				line = line.Trim();
				if (line.Length == 0) continue;

				string cmd = line;
				string arg = null;
				int sp = line.IndexOf(' ');
				if (sp > 0)
				{
					cmd = line.Substring(0, sp).Trim();
					arg = line.Substring(sp + 1).Trim();
				}

				try
				{
					DispatchCommand(cmd, arg, receivedDir);
				}
				catch (Exception ex)
				{
					Console.WriteLine("命令错误: {0}", ex.Message);
				}
			}
		}

		private static void DispatchCommand(string cmd, string arg, string receivedDir)
		{
			if (string.Equals(cmd, "quit", StringComparison.OrdinalIgnoreCase)
				|| string.Equals(cmd, "exit", StringComparison.OrdinalIgnoreCase))
			{
				_running = false;
				return;
			}
			if (string.Equals(cmd, "help", StringComparison.OrdinalIgnoreCase)
				|| string.Equals(cmd, "?", StringComparison.OrdinalIgnoreCase))
			{
				SetupSheetOps.PrintHelp();
				return;
			}

			var data = SetupSheetStore.Latest;
			if (string.Equals(cmd, "summary", StringComparison.OrdinalIgnoreCase)
				|| string.Equals(cmd, "s", StringComparison.OrdinalIgnoreCase))
			{
				SetupSheetOps.PrintSummary(data);
				return;
			}
			if (string.Equals(cmd, "text", StringComparison.OrdinalIgnoreCase)
				|| string.Equals(cmd, "plain", StringComparison.OrdinalIgnoreCase))
			{
				if (data == null)
				{
					Console.WriteLine("尚无已还原对象。请先 POST 或 load。");
					return;
				}
				SetupSheetOps.PrintPlainText(data);
				string txtPath = Path.Combine(receivedDir, "latest-plain.txt");
				SetupSheetOps.SavePlainText(data, txtPath);
				Console.WriteLine("明文已另存: {0}", txtPath);
				return;
			}
			if (string.Equals(cmd, "tools", StringComparison.OrdinalIgnoreCase)
				|| string.Equals(cmd, "t", StringComparison.OrdinalIgnoreCase))
			{
				SetupSheetOps.PrintToolPaths(data);
				return;
			}
			if (string.Equals(cmd, "tool", StringComparison.OrdinalIgnoreCase))
			{
				if (string.IsNullOrEmpty(arg))
				{
					Console.WriteLine("用法: tool <刀路名|NC名|刀具名>");
					return;
				}
				SetupSheetOps.PrintToolPathDetail(SetupSheetOps.FindToolPath(data, arg));
				return;
			}
			if (string.Equals(cmd, "positions", StringComparison.OrdinalIgnoreCase)
				|| string.Equals(cmd, "pos", StringComparison.OrdinalIgnoreCase))
			{
				SetupSheetOps.PrintSummary(data);
				return;
			}
			if (string.Equals(cmd, "images", StringComparison.OrdinalIgnoreCase)
				|| string.Equals(cmd, "img", StringComparison.OrdinalIgnoreCase))
			{
				if (data == null)
				{
					Console.WriteLine("尚无已还原对象。请先 POST 一份程序单 JSON。");
					return;
				}
				string dir = Path.Combine(receivedDir, "images_" + DateTime.Now.ToString("yyyyMMdd-HHmmss"));
				int n = SetupSheetOps.SavePreviewImages(data, dir);
				Console.WriteLine("共导出 {0} 张预览图 → {1}", n, dir);
				return;
			}
			if (string.Equals(cmd, "dump", StringComparison.OrdinalIgnoreCase))
			{
				if (data == null)
				{
					Console.WriteLine("尚无已还原对象。");
					return;
				}
				string path = Path.Combine(receivedDir, "latest-object.json");
				File.WriteAllText(path, SetupSheetOps.Serialize(data), new UTF8Encoding(false));
				Console.WriteLine("已将对象重新序列化到: {0}", path);
				return;
			}
			if (string.Equals(cmd, "path", StringComparison.OrdinalIgnoreCase))
			{
				Console.WriteLine("原始 JSON: {0}", SetupSheetStore.LatestJsonPath ?? "(尚无)");
				Console.WriteLine("明文 TXT : {0}", SetupSheetStore.LatestTxtPath ?? "(尚无)");
				return;
			}
			if (string.Equals(cmd, "load", StringComparison.OrdinalIgnoreCase))
			{
				// 从已落盘文件再次还原，方便离线调试
				string file = arg;
				if (string.IsNullOrEmpty(file))
					file = SetupSheetStore.LatestJsonPath;
				if (string.IsNullOrEmpty(file) || !File.Exists(file))
				{
					Console.WriteLine("用法: load [json文件路径]");
					return;
				}
				string json = File.ReadAllText(file, Encoding.UTF8);
				var sheet = SetupSheetOps.Deserialize(json);
				string txtPath = Path.ChangeExtension(file, ".txt");
				if (string.Equals(Path.GetExtension(file), ".txt", StringComparison.OrdinalIgnoreCase))
					txtPath = Path.Combine(receivedDir, "loaded-plain.txt");
				SetupSheetOps.SavePlainText(sheet, txtPath);
				SetupSheetStore.SetLatest(sheet, file, txtPath);
				Console.WriteLine("已从文件还原对象: {0}", file);
				Console.WriteLine("明文已写入: {0}", txtPath);
				SetupSheetOps.PrintPlainText(sheet);
				return;
			}

			Console.WriteLine("未知命令: {0}  （输入 help 查看）", cmd);
		}

		private static void HandleRequest(HttpListenerContext context, string receivedDir)
		{
			HttpListenerRequest request = context.Request;
			HttpListenerResponse response = context.Response;
			string method = request.HttpMethod ?? "";
			string path = request.Url != null ? request.Url.AbsolutePath : "/";

			try
			{
				if (string.Equals(method, "GET", StringComparison.OrdinalIgnoreCase))
				{
					string help =
						"JmSetupSheetReceiver — 机明程序单接收端演示\r\n\r\n" +
						"POST application/json → 还原为 SetupsheetData，落盘 JSON 与明文 TXT。\r\n" +
						"成功返回 HTTP 200: {\"success\":true,\"message\":\"received\"}\r\n" +
						"控制台命令: summary / text / tools / tool <名> / images / dump / load\r\n";
					WriteText(response, 200, "text/plain; charset=utf-8", help);
					Console.WriteLine("[{0:HH:mm:ss}] GET {1} -> 200 (probe)", DateTime.Now, path);
					return;
				}

				if (!string.Equals(method, "POST", StringComparison.OrdinalIgnoreCase))
				{
					WriteText(response, 405, "text/plain; charset=utf-8", "Method Not Allowed. Use POST.");
					Console.WriteLine("[{0:HH:mm:ss}] {1} {2} -> 405", DateTime.Now, method, path);
					return;
				}

				// 机明推送为 UTF-8 JSON。Content-Type 若未带 charset，HttpListener.ContentEncoding
				// 在中文 Windows 上常为系统默认（GBK），误解码会弄坏中文并导致反序列化失败。
				string body = ReadRequestBodyAsUtf8(request);

				SetupsheetData sheet = null;
				string deserializeError = null;
				try
				{
					sheet = SetupSheetOps.Deserialize(body);
				}
				catch (Exception ex)
				{
					deserializeError = ex.Message;
				}

				// 始终保留原始报文；另存缩进分行的 .pretty.json 便于阅读
				string stamp = DateTime.Now.ToString("yyyyMMdd-HHmmss-fff");
				string fileName = stamp + ".json";
				string filePath = Path.Combine(receivedDir, fileName);
				File.WriteAllText(filePath, body ?? string.Empty, new UTF8Encoding(false));

				string prettyPath = null;
				if (sheet != null)
				{
					try
					{
						prettyPath = Path.Combine(receivedDir, stamp + ".pretty.json");
						File.WriteAllText(prettyPath, SetupSheetOps.Serialize(sheet), new UTF8Encoding(false));
					}
					catch
					{
						prettyPath = null;
					}
				}
				else if (_prettyJson)
				{
					// 还原失败时 --pretty 无法生成对象美化稿，仅保留原文
				}

				int len = body == null ? 0 : Encoding.UTF8.GetByteCount(body);

				if (sheet != null)
				{
					string txtPath = Path.ChangeExtension(filePath, ".txt");
					SetupSheetOps.SavePlainText(sheet, txtPath);
					SetupSheetStore.SetLatest(sheet, filePath, txtPath);
					Console.WriteLine();
					Console.WriteLine("[{0:HH:mm:ss}] POST {1} -> 对象已还原 (SetupsheetData)", DateTime.Now, path);
					Console.WriteLine("  原文 JSON : {0}  ({1} bytes)", fileName, len);
					if (prettyPath != null)
						Console.WriteLine("  分行 JSON : {0}", Path.GetFileName(prettyPath));
					Console.WriteLine("  明文 TXT  : {0}", Path.GetFileName(txtPath));
					Console.WriteLine("---------- 明文开始 ----------");
					SetupSheetOps.PrintPlainText(sheet);
					Console.WriteLine("---------- 明文结束 ----------");
					Console.Write("> ");
				}
				else
				{
					Console.WriteLine();
					Console.WriteLine("[{0:HH:mm:ss}] POST {1} -> JSON 已落盘，但对象还原失败", DateTime.Now, path);
					Console.WriteLine("  保存: {0}  ({1} bytes)", fileName, len);
					Console.WriteLine("  原因: {0}", deserializeError);
					Console.Write("> ");
				}

				if (_forceFail)
				{
					WriteText(response, 500, "application/json; charset=utf-8",
						"{\"success\":false,\"message\":\"demo forced failure (--fail)\"}");
					return;
				}

				const string okJson = "{\"success\":true,\"message\":\"received\"}";
				WriteText(response, 200, "application/json; charset=utf-8", okJson);
			}
			catch (Exception ex)
			{
				try
				{
					WriteText(response, 500, "text/plain; charset=utf-8", "Error: " + ex.Message);
				}
				catch { }
				Console.WriteLine("[{0:HH:mm:ss}] ERROR: {1}", DateTime.Now, ex.Message);
			}
			finally
			{
				try { response.OutputStream.Close(); } catch { }
			}
		}

		/// <summary>
		/// 按 UTF-8 读取请求体（忽略可能错误的 ContentEncoding）。
		/// </summary>
		private static string ReadRequestBodyAsUtf8(HttpListenerRequest request)
		{
			using (var ms = new MemoryStream())
			{
				request.InputStream.CopyTo(ms);
				byte[] raw = ms.ToArray();
				if (raw.Length >= 3 && raw[0] == 0xEF && raw[1] == 0xBB && raw[2] == 0xBF)
				{
					return Encoding.UTF8.GetString(raw, 3, raw.Length - 3);
				}
				return Encoding.UTF8.GetString(raw);
			}
		}

		private static void WriteText(HttpListenerResponse response, int statusCode, string contentType, string text)
		{
			byte[] buffer = Encoding.UTF8.GetBytes(text ?? string.Empty);
			response.StatusCode = statusCode;
			response.ContentType = contentType;
			response.ContentEncoding = Encoding.UTF8;
			response.ContentLength64 = buffer.Length;
			response.OutputStream.Write(buffer, 0, buffer.Length);
		}
	}
}