using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using OfficeOpenXml.FormulaParsing.Excel.Functions.Math;
using WIDESEA_Core.BaseRepository;
using WIDESEA_Core.BaseServices;
using WIDESEA_DTO.BasicInfo;
using WIDESEA_IBasicInfoServices;
using WIDESEA_Model.Models;

namespace WIDESEA_BasicInfoServices
{
    public class ActivationCodeService : ServiceBase<Dt_ActivationCode, IRepository<Dt_ActivationCode>>, IActivationCodeService
    {
        private readonly IRepository<Dt_CharMapping> _charMappingRepository;
        private readonly IRepository<Dt_RuntimeCode> _runtimeCodeRepository;
        private readonly IRepository<Dt_Products> _productRepository;

        public ActivationCodeService(IRepository<Dt_ActivationCode> BaseDal, IRepository<Dt_CharMapping> charMappingRepository, IRepository<Dt_RuntimeCode> runtimeCodeRepository, IRepository<Dt_Products> productRepository) : base(BaseDal)
        {
            _charMappingRepository = charMappingRepository;
            _runtimeCodeRepository = runtimeCodeRepository;
            _productRepository = productRepository;
        }

        /// <summary>
        /// 生成激活码
        /// </summary>
        /// <param name="activationDTO">包含运行码、设备ID和产品名称的数据传输对象</param>
        /// <returns>生成的激活码</returns>
        public string GenerateActivationCode(ActivationCodeDTO activationDTO)
        {
            // 查询运行码对应的模型
            Dt_RuntimeCode runtimeCodeModel = _runtimeCodeRepository.QueryFirst(x => x.RuntimeCode == activationDTO.RuntimeCode);
            // 1. 检查运行码是否已存在
            if (runtimeCodeModel == null)
            {
                throw new InvalidOperationException($"无效的运行码: {activationDTO.RuntimeCode}");
            }

            // 查询激活码对应的模型
            Dt_ActivationCode activationCodeModel = BaseDal.QueryFirst(x => x.RuntimeCode == activationDTO.RuntimeCode);
            // 2. 检查激活码是否已存在
            if (activationCodeModel != null)
            {
                return activationCodeModel.ActivationCode;
            }

            int productId = -1;
            // 查询产品对应的模型
            Dt_Products product = _productRepository.QueryFirst(x => x.ProductName == activationDTO.ProductName);
            if (product != null)
            {
                productId = product.Id;
            }

            // 3. 检查设备ID和产品ID是否匹配
            if (runtimeCodeModel.DeviceId != activationDTO.DeviceId || runtimeCodeModel.ProductId != productId)
            {
                throw new InvalidOperationException($"设备ID或产品ID不匹配: {activationDTO.DeviceId}, {productId}");
            }

            // 4. 生成激活码
            // 去除运行码中的"-"字符
            string baseRandom = activationDTO.RuntimeCode.Replace("-", string.Empty);

            // 查询字符映射字典
            Dictionary<char, (char output, int shift)> mappingDict = _charMappingRepository.QueryData().ToDictionary(x => x.InputChar.ToCharArray().FirstOrDefault(), x => (x.OutputChar.ToCharArray().FirstOrDefault(), x.ShiftFactor));

            char[] result = new char[baseRandom.Length];
            int length = baseRandom.Length;

            // 遍历运行码的每个字符进行转换
            for (int i = 0; i < length; i++)
            {
                char current = baseRandom[i];
                if (current == '-')
                    continue;
                if (!mappingDict.TryGetValue(current, out var mapping))
                    throw new InvalidOperationException($"无效字符: {current}");

                // 特殊变换：每5个字符增加复杂度
                char mappedChar = (i % 5 == 4)
                    ? ApplySpecialTransform(mapping.output, mapping.shift)
                    : mapping.output;

                result[i] = mappedChar;
            }

            // 格式化激活码
            string activationCode = FormatCode(new string(result));

            // 5. 存储激活码
            StoredActivationCode(activationDTO.DeviceId, baseRandom, activationCode, activationDTO.RuntimeCode, productId);

            return activationCode;
        }

        /// <summary>
        /// 对输入字符进行基于ASCII码的二次变换。
        /// </summary>
        /// <param name="c">要变换的字符。</param>
        /// <param name="position">字符的位置，用于计算变换值。</param>
        /// <returns>变换后的字符。</returns>
        private char ApplySpecialTransform(char c, int position)
        {
            // 将字符转换为ASCII码
            int ascii = (int)c;
            
            // 计算变换后的ASCII码值，基于字符的位置进行偏移，并确保结果在0-35范围内
            int transformed = (ascii + position) % 36 + 48;
            
            // 如果变换后的ASCII码值在':'到'@'之间（即字符'9'到字符'@'），则再偏移7个位置
            if (transformed >= ':' && transformed <= '@')
            {
                transformed += 7;
            }
            
            // 将变换后的ASCII码值转换回字符并返回
            return (char)transformed;
        }

        /// <summary>
        /// 将原始字符串格式化为XXXXX-XXXXX-XXXXX-XXXXX-XXXXX的形式
        /// </summary>
        /// <param name="raw">需要格式化的原始字符串，长度必须为25个字符</param>
        private string FormatCode(string raw)
        {
            // 格式化为XXXXX-XXXXX-XXXXX-XXXXX-XXXXX
            return string.Join("-",
                raw.Substring(0, 5),
                raw.Substring(5, 5),
                raw.Substring(10, 5),
                raw.Substring(15, 5),
                raw.Substring(20, 5));
        }

        /// <summary>
        /// 存储激活码信息到数据库
        /// </summary>
        /// <param name="deviceId">设备ID，用于标识特定设备</param>
        /// <param name="baseRandom">基础随机码，用于生成激活码的随机字符串</param>
        /// <param name="activationCode">激活码，用于产品激活的唯一代码</param>
        /// <param name="runtimeCode">运行时码，用于验证激活状态的代码</param>
        /// <param name="productId">产品ID，用于标识不同的产品</param>
        private void StoredActivationCode(string deviceId, string baseRandom, string activationCode, string runtimeCode, int productId)
        {
            Dt_ActivationCode activationRecord = new Dt_ActivationCode
            {
                MappedRandom = baseRandom,
                ActivationCode = activationCode,
                DeviceId = deviceId,
                IsUsed = false,
                ProductId = productId,
                ExpiresTime = null,
                RuntimeCode = runtimeCode
            };

            BaseDal.AddData(activationRecord);
        }
    }
}