using AllBase.Helper;
using AllBase;
using AllBase.Model;
using Work.Store.Api;
using System.Threading;
using System.Threading.Tasks;
using Newtonsoft.Json;
using System;
using System.Collections.Generic;
using System.IO;
using System.Drawing;
using System.Drawing.Drawing2D;
using System.Drawing.Imaging;
using System.Net.Http;
using System.Linq;
using System.Text;

namespace Work.Services;

public sealed class ComplianceGoods
{
	public const string Cloud = "云端收藏";
	public const string Library = "我的商品库";

	public string id { get; set; }
	public string name { get; set; }
	public string image { get; set; }
	public string type { get; set; }
	public byte? platform { get; set; }
}

public sealed class ComplianceResult
{
	public string Text { get; internal set; }
	public string[] Hits { get; internal set; } = Array.Empty<string>();
	public int HitImageNumber { get; internal set; }
	public string Error { get; internal set; }
	public string Status => Error != null ? "失败，可重试" : Hits.Length == 0 ? "安全" : "有风险";
	public string Summary => Error != null ? "失败：" + Error :
		Hits.Length == 0 ? Status : $"有风险：{HitSource}命中关键词：{string.Join("，", Hits)}";
	private string HitSource => HitImageNumber == 0 ? "标题" : $"第 {HitImageNumber} 张图片";
}

public sealed class ComplianceBatchResult
{
	public int Safe { get; internal set; }
	public int Risk { get; internal set; }
	public int Failed { get; internal set; }
	public int Unfinished { get; internal set; }
}

public static class GoodsComplianceService
{
	private static readonly HttpClient ImageClient = new HttpClient(new HttpClientHandler { UseCookies = false })
	{
		Timeout = TimeSpan.FromSeconds(30),
		MaxResponseContentBufferSize = 32 * 1024 * 1024
	};
	private static readonly SemaphoreSlim BatchGate = new SemaphoreSlim(1, 1);

	public static async Task<ComplianceBatchResult> DetectSelectedAsync(IReadOnlyList<ComplianceGoods> items,
		Func<ComplianceGoods, Product> readProduct, Action<string, string> update, CancellationToken cancellationToken = default)
	{
		if (items == null || items.Count == 0) throw new ArgumentException("请选择商品。", nameof(items));
		if (readProduct == null) throw new ArgumentNullException(nameof(readProduct));
		if (update == null) throw new ArgumentNullException(nameof(update));
		if (!BatchGate.Wait(0)) throw new InvalidOperationException("已有商品正在检测。");
		try
		{
			var options = GlobalConfig.GlobalSettings.GoodsCompliance;
			var words = ValidateOptions(options);
			var path = QueuePath();
			var pending = ReadPending(path);
			if (items.Any(InvalidItem)) throw new ArgumentException("缺少商品 ID 或来源。", nameof(items));
			var selected = items.GroupBy(x => Tuple.Create(x.type, x.id)).Select(g => g.First()).ToList();
			var existing = new HashSet<Tuple<string, string>>(pending.Select(x => Tuple.Create(x.type, x.id)));
			pending.AddRange(selected.Where(x => existing.Add(Tuple.Create(x.type, x.id))));
			SavePending(path, pending);

			var batch = new ComplianceBatchResult { Unfinished = selected.Count };
			foreach (ComplianceGoods item in selected)
			{
				if (cancellationToken.IsCancellationRequested) break;
				update(item.id, "读取详情中");
				ComplianceResult result;
				try
				{
					//item.type
					var product = await Task.Run(() => readProduct(item), cancellationToken);
					result = await DetectProductAsync(product, options, words,
						number => update(item.id, $"正在检测第 {number} 张图片"), cancellationToken);
					if (result.Error == null)
					{
						try
						{
							if (item.type == ComplianceGoods.Library)
							{
								var url = BaseClass.BuildPDDObjString("product/SaveProductSafety");
								var data = UserLogin.GetSignature();
								data += "&user_name=" + BaseClass.UserName;
								data += "&id=" + item.id;
								string html = await GetHtml.PostJsonAsync(url, data);


							}
							else
							{
								await StoreApiClient.Instance.CloudGoods.SaveProductSafety(new SaveProductSafetyRequest
								{
									UserName = GetUserName(),
									ProductId = product.ProductId,
									IsSafe = result.Hits.Length == 0
								});
							}
						}
						catch (Exception ex)
						{
							result.Error = $"检测结果为{result.Status}，上报失败：{ex.Message}";
						}
					}
				}
				catch (OperationCanceledException) when (cancellationToken.IsCancellationRequested)
				{
					update(item.id, "已停止");
					break;
				}
				catch (Exception ex) { result = new ComplianceResult { Error = ex.Message }; }
				if (result.Error == null)
				{
					var remaining = pending.Where(x => x.type != item.type || x.id != item.id).ToList();
					try { SavePending(path, remaining); pending = remaining; }
					catch (Exception ex) { result.Error = ex.Message; }
				}
				if (result.Error != null) batch.Failed++;
				else if (result.Hits.Length > 0) batch.Risk++;
				else batch.Safe++;
				batch.Unfinished--;
				update(item.id, result.Summary);
			}
			return batch;
		}
		finally { BatchGate.Release(); }
	}

	private static string QueuePath()
	{
		var username = BaseClass.UserName;
		if (string.IsNullOrWhiteSpace(username)) throw new InvalidOperationException("请先登录。");
		var user = Convert.ToBase64String(Encoding.UTF8.GetBytes(username)).Replace('/', '_').Replace('+', '-');
		return Path.Combine(AppDomain.CurrentDomain.BaseDirectory, "data", "config", "goods_compliance_" + user + ".json");
	}

	private static bool InvalidItem(ComplianceGoods item) =>
		item == null || string.IsNullOrWhiteSpace(item.id) || string.IsNullOrWhiteSpace(item.type);

	private static List<ComplianceGoods> ReadPending(string path)
	{
		if (!File.Exists(path)) return new List<ComplianceGoods>();
		var items = JsonConvert.DeserializeObject<List<ComplianceGoods>>(File.ReadAllText(path));
		if (items == null || items.Any(InvalidItem))
			throw new InvalidDataException("待检测配置无效，请检查 " + path);
		return items;
	}

	private static void SavePending(string path, List<ComplianceGoods> items)
	{
		Directory.CreateDirectory(Path.GetDirectoryName(path));
		var temp = path + ".tmp";
		File.WriteAllText(temp, JsonConvert.SerializeObject(items));
		if (File.Exists(path)) File.Replace(temp, path, null);
		else File.Move(temp, path);
	}

	public static async Task DetectAsync(IReadOnlyList<Product> products, ComplianceOptions options,
		Action<Product, ComplianceResult> completed, Action<Product> started = null)
	{
		if (products == null) throw new ArgumentNullException(nameof(products));
		if (completed == null) throw new ArgumentNullException(nameof(completed));
		var words = ValidateOptions(options);
		foreach (var product in products)
		{
			started?.Invoke(product);
			var result = await DetectProductAsync(product, options, words);
			if (result.Error == null)
			{
				try
				{
					await StoreApiClient.Instance.CloudGoods.SaveProductSafety(new SaveProductSafetyRequest
					{
						UserName = GetUserName(),
						ProductId = product.ProductId,
						IsSafe = result.Hits.Length == 0
					});
				}
				catch (Exception ex)
				{
					result.Error = $"检测结果为{result.Status}，上报失败：{ex.Message}";
				}
			}
			completed(product, result);
		}
	}

	private static string[] ValidateOptions(ComplianceOptions options)
	{
		var words = Keywords(options?.Keywords);
		if (words.Length == 0) throw new ArgumentException("请先在系统设置的「商品 AI 检测」中保存 AI 检测关键词。");
		if (options.MainCount <= 0 || options.DetailCount < 0)
			throw new ArgumentException("请检查检测关键词和图片数量。");
		return words;
	}

	private static async Task<ComplianceResult> DetectProductAsync(Product product, ComplianceOptions options,
		string[] words, Action<int> imageStarted = null, CancellationToken cancellationToken = default)
	{
		var result = new ComplianceResult();
		try
		{
			cancellationToken.ThrowIfCancellationRequested();
			if (string.IsNullOrWhiteSpace(product?.ProductId)) throw new InvalidDataException("缺少商品 ID。");
			result.Hits = Matches(product.Title ?? string.Empty, words);
			if (result.Hits.Length > 0)
			{
				result.Text = product.Title;
				return result;
			}
			var urls = SelectImages(product.MainImages, options.MainCount)
				.Concat(SelectImages(product.DetailImages, options.DetailCount));
			if (options.IncludeSku) urls = urls.Concat(SelectImages(product.Skus?.Select(s => s?.ImageUrl), null));
			var texts = new List<string>();
			int imageNumber = 0;
			foreach (var url in urls.Distinct(StringComparer.Ordinal))
			{
				cancellationToken.ThrowIfCancellationRequested();
				imageNumber++;
				imageStarted?.Invoke(imageNumber);
				try
				{
					var jpeg = await DownloadInspectionImageAsync(url);
					cancellationToken.ThrowIfCancellationRequested();
					var lines = await StoreApiClient.Instance.CloudGoods.RecognizeAsync(BaseClass.GetMd5(url), jpeg);

					BaseClass.ImageAnalysisQuota -= 1;

					var imageText = string.Join(Environment.NewLine, lines);
					texts.AddRange(lines);
					result.Hits = Matches(imageText, words);
					if (result.Hits.Length > 0)
					{
						result.HitImageNumber = imageNumber;
						break;
					}
				}
				catch (Exception ex) when (!cancellationToken.IsCancellationRequested)
				{
					throw new InvalidDataException($"第 {imageNumber} 张图片检测失败：{ex.Message}", ex);
				}
			}
			cancellationToken.ThrowIfCancellationRequested();
			if (imageNumber == 0) throw new InvalidDataException("所选检测范围内没有图片。");
			result.Text = string.Join(Environment.NewLine, texts);

		}
		catch (OperationCanceledException) when (cancellationToken.IsCancellationRequested) { throw; }
		catch (Exception ex) { result.Error = ex.Message; }
		return result;
	}

	private static IEnumerable<string> SelectImages(IEnumerable<string> urls, int? count) =>
		(urls ?? Enumerable.Empty<string>()).Where(url => !string.IsNullOrWhiteSpace(url)).Select(url => url.Trim())
			.Distinct(StringComparer.Ordinal).Take(count ?? int.MaxValue);

	private static async Task<byte[]> DownloadInspectionImageAsync(string url)
	{
		if (!Uri.TryCreate(url, UriKind.Absolute, out var uri) ||
			(uri.Scheme != Uri.UriSchemeHttp && uri.Scheme != Uri.UriSchemeHttps))
			throw new InvalidDataException("图片链接必须为 HTTP 或 HTTPS 地址。");
		var bytes = await ImageClient.GetByteArrayAsync(uri).ConfigureAwait(false);
		const int maxSide = 600;
		using (var input = new MemoryStream(bytes))
		using (var source = Image.FromStream(input))
		{
			var scale = Math.Min(1d, (double)maxSide / Math.Max(source.Width, source.Height));
			int width = Math.Max(1, (int)Math.Round(source.Width * scale));
			int height = Math.Max(1, (int)Math.Round(source.Height * scale));
			using var canvas = new Bitmap(width, height, PixelFormat.Format24bppRgb);
			using var output = new MemoryStream();
			using (var g = Graphics.FromImage(canvas))
			{
				g.Clear(Color.White);
				g.InterpolationMode = InterpolationMode.HighQualityBicubic;
				g.DrawImage(source, new Rectangle(0, 0, width, height),
					0, 0, source.Width, source.Height, GraphicsUnit.Pixel);
			}
			canvas.Save(output, ImageFormat.Jpeg);
			return output.ToArray();
		}
	}

	public static string[] Keywords(string value) =>
		System.Text.RegularExpressions.Regex.Split(value ?? "", @"[,，;；|\s]+")
			.Where(x => x.Length > 0).Distinct(StringComparer.OrdinalIgnoreCase).ToArray();

	public static string[] Matches(string recognized, string[] keywords) =>
		keywords.Where(x => recognized.IndexOf(x, StringComparison.OrdinalIgnoreCase) >= 0).ToArray();
	public static string GetUserName()
	{
		return string.IsNullOrEmpty(BaseClass.ParentUserName) ? BaseClass.UserName : BaseClass.ParentUserName;
	}
}