using AllBase.Model.Result;
using Newtonsoft.Json;
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Linq;

namespace AllBase.Model
{
	/// <summary>
	/// 通用商品Model
	/// </summary>
	public class Product
	{
		public Product()
		{
			CategoryIds = new List<int>();
			Attributes = new List<ProductAttribute>();
			MainImages = new List<string>();
			DetailImages = new List<string>();
			Specs = new List<ProductSpec>();
			Skus = new List<ProductSku>();
			Extensions = new Dictionary<string, string>();
		}

		#region 来源

		/// <summary>
		/// 来源平台
		/// </summary>
		public PlatformType Platform { get; set; }

		/// <summary>
		/// 来源商品链接
		/// </summary>
		public string SourceUrl { get; set; }

		/// <summary>
		/// 来源店铺编号
		/// </summary>
		public string ShopId { get; set; }

		/// <summary>
		/// 来源店铺名称
		/// </summary>
		public string ShopName { get; set; }

		#endregion

		#region 基本信息
		/// <summary>
		/// 商家编号
		/// </summary>
		public string ProductId { get; set; }
		/// <summary>
		/// 标题
		/// </summary>
		public string Title { get; set; }

		/// <summary>
		/// 描述
		/// </summary>
		public string Description { get; set; }
		/// <summary>
		/// 品牌
		/// </summary>
		public string Brand { get; set; }

		/// <summary>
		/// 类目
		/// </summary>
		public int CategoryId { get; set; }
		/// <summary>
		/// 类目编号路径，从一级类目到叶子类目，叶子类目为最后一项
		/// </summary>
		public List<int> CategoryIds { get; set; }

		/// <summary>
		/// 商品属性（非销售维度），如材质、产地
		/// </summary>
		public List<ProductAttribute> Attributes { get; set; }

		#endregion

		#region 媒体
		/// <summary>
		/// 缩略图
		/// </summary>
		public string ThumbUrl { get; set; }
		/// <summary>
		/// 主图
		/// </summary>
		public List<string> MainImages { get; set; }

		/// <summary>
		/// 详情图
		/// </summary>
		public List<string> DetailImages { get; set; }

		/// <summary>
		/// 视频地址，可为空
		/// </summary>
		public string Video { get; set; }

		#endregion

		#region 销售

		/// <summary>
		/// 规格
		/// </summary>
		public List<ProductSpec> Specs { get; set; }

		/// <summary>
		/// SKU
		/// </summary>
		public List<ProductSku> Skus { get; set; }
		/// <summary>
		/// 扩展数据
		/// </summary>
		public Dictionary<string, string> Extensions { get; set; }

		/// <summary>
		/// 划线价/市场价（商品级）
		/// </summary>
		public decimal? MarketPrice { get; set; }

		/// <summary>
		/// 销量
		/// </summary>
		public long? SalesCount { get; set; }

		/// <summary>
		/// 来源平台展示的销量文案，如“已拼10万+件”
		/// </summary>
		public string SalesText { get; set; }

		/// <summary>
		/// 来源平台上架时间
		/// </summary>
		public DateTime? ListingTime { get; set; }

		/// <summary>
		/// SKU最低售价
		/// </summary>
		[JsonIgnore]
		public decimal MinPrice
		{
			get { return Skus.Any() ? Skus.Min(a => a.Price) : 0; }
		}

		/// <summary>
		/// SKU最高售价
		/// </summary>
		[JsonIgnore]
		public decimal MaxPrice
		{
			get { return Skus.Any() ? Skus.Max(a => a.Price) : 0; }
		}

		/// <summary>
		/// 所有SKU库存总和
		/// </summary>
		[JsonIgnore]
		public int TotalStock
		{
			get { return Skus.Sum(a => a.Stock); }
		}

		#endregion


		/// <summary>
		/// 校验商品数据，返回错误信息，null 表示通过。
		/// </summary>
		public string Validate()
		{
			if (string.IsNullOrEmpty(ProductId)) return "缺少商品编号";
			if (MainImages.Count == 0) return "缺少主图";
			if (Skus.Count == 0) return "缺少SKU";

			if (Specs.Any(s => string.IsNullOrEmpty(s.Name) || s.Values.Count == 0))
				return "规格名称为空或规格值为空";
			if (Specs.GroupBy(s => s.Name).Any(g => g.Count() > 1))
				return "规格名称重复";
			if (Specs.Any(s => s.Values.Distinct().Count() != s.Values.Count))
				return "同一规格下规格值重复";

			foreach (var sku in Skus)
			{
				// 每个 SKU 在每个规格维度上恰好选一个值
				if (sku.Specs.Count != Specs.Count)
					return "SKU规格数量与商品规格不一致：" + sku.SkuId;
				foreach (var s in sku.Specs)
				{
					var spec = Specs.FirstOrDefault(a => a.Name == s.Name);
					if (spec == null)
						return "SKU使用了不存在的规格：" + s.Name;
					if (!spec.Values.Contains(s.Value))
						return "SKU使用了不存在的规格值：" + s.Name + ":" + s.Value;
				}
				if (sku.Specs.GroupBy(a => a.Name).Any(g => g.Count() > 1))
					return "SKU同一规格重复选择：" + sku.SkuId;
			}
			return null;
		}
	}

	/// <summary>
	/// 商品规格定义，如 颜色：红色、蓝色
	/// </summary>
	public class ProductSpec
	{
		public ProductSpec()
		{
			Values = new List<string>();
		}

		/// <summary>
		/// 规格名称，如颜色、尺码，商品内唯一
		/// </summary>
		public string Name { get; set; }

		/// <summary>
		/// 规格可选值，如红色、XL，规格内唯一
		/// </summary>
		public List<string> Values { get; set; }
	}

	/// <summary>
	/// 商品属性（非销售维度）
	/// </summary>
	public class ProductAttribute
	{
		public ProductAttribute()
		{
			Values = new List<string>();
		}

		/// <summary>
		/// 属性名称，如材质
		/// </summary>
		public string Name { get; set; }

		/// <summary>
		/// 属性值列表
		/// </summary>
		public List<string> Values { get; set; }
	}

	/// <summary>
	/// 商品销售单元
	/// </summary>
	public class ProductSku
	{
		public ProductSku()
		{
			Specs = new List<ProductSkuSpec>();
		}

		/// <summary>
		/// SKU编号
		/// </summary>
		public string SkuId { get; set; }

		/// <summary>
		/// 当前售价（元）
		/// </summary>
		public decimal Price { get; set; }

		/// <summary>
		/// 可售库存
		/// </summary>
		public int Stock { get; set; }

		/// <summary>
		/// SKU图片
		/// </summary>
		public string ImageUrl { get; set; }

		/// <summary>
		/// SKU选中的规格值，Name/Value 必须存在于 Product.Specs
		/// </summary>
		public List<ProductSkuSpec> Specs { get; set; }
	}

	/// <summary>
	/// SKU选中的一个规格值
	/// </summary>
	public class ProductSkuSpec
	{
		/// <summary>
		/// 规格名称，对应 ProductSpec.Name
		/// </summary>
		public string Name { get; set; }

		/// <summary>
		/// 规格值，对应 ProductSpec.Values 中的一项
		/// </summary>
		public string Value { get; set; }
	}
}