using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using WIDESEA_Core;
using WIDESEA_Core.BaseRepository;
using WIDESEA_Core.BaseServices;
using WIDESEA_DTO.BasicInfo;
using WIDESEA_IBasicInfoServices;
using WIDESEA_Model.Models;

namespace WIDESEA_BasicInfoServices
{
    public class RuntimeCodeService : ServiceBase<Dt_RuntimeCode, IRepository<Dt_RuntimeCode>>, IRuntimeCodeService
    {
        private const int BaseRandomLength = 25;
        private const int RuntimeCodeLength = 25;

        private readonly IRepository<Dt_Products> _productRepository;

        public RuntimeCodeService(IRepository<Dt_RuntimeCode> BaseDal, IRepository<Dt_Products> productRepository) : base(BaseDal)
        {
            _productRepository = productRepository;
        }


        // 生成设备运行码主方法
        public WebResponseContent GenerateRuntimeCode(DeviceInfoDTO deviceInfo)
        {
            try
            {
                int productId = -1;
                Dt_Products product = _productRepository.QueryFirst(x => x.ProductName == deviceInfo.ProductName);
                if (product != null)
                {
                    productId = product.Id;
                }

                Dt_RuntimeCode runtimeCodeModel = BaseDal.QueryFirst(x => x.DeviceId == deviceInfo.DeviceId && x.ProductId == productId);
                if (runtimeCodeModel != null)
                {
                    return WebResponseContent.Instance.OK(data: runtimeCodeModel.RuntimeCode);
                }

            GenerateBaseRandomL:
                // 1. 生成基础随机码
                string baseRandom = GenerateBaseRandom();

                // 2. 添加校验位
                char checkDigit = CalculateCheckDigit(baseRandom);

                // 3. 组合完整运行码
                string runtimeCode = FormatRuntimeCode(baseRandom + checkDigit);

                if (BaseDal.QueryFirst(x => x.RuntimeCode == runtimeCode) != null)
                {
                    goto GenerateBaseRandomL;
                }

                // 4. 存储到数据库
                StoreRuntimeCode(deviceInfo.DeviceId, checkDigit.ToString(), baseRandom, runtimeCode, deviceInfo.DeviceInfoJson, productId);

                return WebResponseContent.Instance.OK(data: runtimeCode);
            }
            catch (Exception ex)
            {
                return WebResponseContent.Instance.Error(message: "生成运行码失败");
            }

        }

        // 生成20位随机基础码
        private string GenerateBaseRandom()
        {
            const string chars = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ";
            var random = new Random();
            return new string(Enumerable.Repeat(chars, BaseRandomLength)
                .Select(s => s[random.Next(s.Length)]).ToArray());
        }

        // 计算Luhn校验位
        private char CalculateCheckDigit(string baseRandom)
        {
            int sum = 0;
            bool alternate = true;

            // 从右向左处理
            for (int i = baseRandom.Length - 1; i >= 0; i--)
            {
                int n = CharToInt(baseRandom[i]);
                sum += alternate ? n : (n * 2 > 9 ? n * 2 - 9 : n * 2);
                alternate = !alternate;
            }

            int checkDigit = (10 - (sum % 10)) % 10;
            return checkDigit.ToString().ToCharArray().FirstOrDefault();
        }

        // 字符转数字
        private int CharToInt(char c)
        {
            return c >= '0' && c <= '9'
                ? c - '0'
                : c - 'A' + 10;
        }

        // 格式化运行码 (XXXXX-XXXXX-XXXXX-XXXXX-XXXXX)
        private string FormatRuntimeCode(string rawCode)
        {
            return string.Join("-",
                rawCode.Substring(0, 5),
                rawCode.Substring(5, 5),
                rawCode.Substring(10, 5),
                rawCode.Substring(15, 5),
                rawCode.Substring(20, 5));
        }

        // 存储到数据库
        private void StoreRuntimeCode(string deviceId, string checkDigit, string baseRandom, string runtimeCode, string deviceInfo, int productId)
        {
            Dt_RuntimeCode runtimeRecord = new Dt_RuntimeCode
            {
                BaseRandom = baseRandom,
                RuntimeCode = runtimeCode,
                DeviceInfo = deviceInfo,
                DeviceId = deviceId,
                CheckDigit = checkDigit,
                ProductId = productId // 假设产品ID为1，实际应用中应根据具体逻辑获取
            };

            BaseDal.AddData(runtimeRecord);
        }
    }
}