using System.Security.Cryptography;
using System.Text;
using Dlhis.Basic.Organization.Response;
using Kurisu.AspNetCore.CustomClass;
using Newtonsoft.Json;

namespace Dlhis.Basic.Organization.Services;

public interface IAliyunClient : ISingletonDependency
{
    Task<AliyunId3MetaVerifyResponse> Id3MetaVerifyAsync(
        string identifyNum,
        string userName,
        string faceBase64,
        string crop = "F");
}

public class AliyunClient : IAliyunClient
{
    private readonly IHttpClientFactory _httpClientFactory;
    private readonly IConfiguration _configuration;
    private readonly string _accessKeyId;
    private readonly string _accessKeySecret;

    private const string Endpoint = "cloudauth.aliyuncs.com";
    private const string ApiVersion = "2019-03-07";

    public AliyunClient(IHttpClientFactory httpClientFactory, IConfiguration configuration, ILogger<AliyunClient> logger)
    {
        _httpClientFactory = httpClientFactory;
        _configuration = configuration;

        _accessKeyId = "LTAI5tAqyWKcBcSvzpc1ZM72";
        _accessKeySecret = "YZMSqsmMGlGZuHw5WU2tqt0mmIBX6h";
    }


    /// <summary>
    /// 使用 Base64 图片进行三要素核验
    /// </summary>
    public async Task<AliyunId3MetaVerifyResponse> Id3MetaVerifyAsync(
        string identifyNum,
        string userName,
        string faceBase64,
        string crop = "F")
    {
        if (faceBase64.Contains(","))
        {
            faceBase64 = faceBase64[(faceBase64.IndexOf(',') + 1)..];
        }

        var parameters = new SortedDictionary<string, string>
        {
            { "Action", "Id3MetaVerify" },
            { "Format", "JSON" },
            { "Version", ApiVersion },
            { "AccessKeyId", _accessKeyId },
            { "SignatureMethod", "HMAC-SHA1" },
            { "SignatureVersion", "1.0" },
            { "SignatureNonce", Guid.NewGuid().ToString("N") },
            { "Timestamp", DateTime.UtcNow.ToString("yyyy-MM-ddTHH:mm:ssZ") },
            { "ParamType", "normal" },
            { "IdentifyNum", identifyNum },
            { "UserName", userName },
            { "FacePicture", faceBase64 },
            { "Crop", crop }
        };

        var signature = ComputeSignature(parameters, "POST", _accessKeySecret);
        var url = $"https://{Endpoint}/?Signature={PercentEncode(signature)}";
        var bodyString = BuildBodyString(parameters);

        using var fallbackClient = _httpClientFactory == null ? new HttpClient() : null;
        var client = _httpClientFactory?.CreateClient() ?? fallbackClient;
        client.DefaultRequestHeaders.Add("Host", Endpoint);
        var content = new StringContent(bodyString, Encoding.UTF8, "application/x-www-form-urlencoded");
        var response = await client.PostAsync(url, content);
        var rawResponse = await response.Content.ReadAsStringAsync();

        return ParseResponse(rawResponse);
    }

    private static AliyunId3MetaVerifyResponse ParseResponse(string rawResponse)
    {
        var result = new AliyunId3MetaVerifyResponse
        {
            RawResponse = rawResponse
        };

        if (string.IsNullOrWhiteSpace(rawResponse))
        {
            return result;
        }

        try
        {
            var response = JsonConvert.DeserializeObject<AliyunId3MetaVerifyApiResponse>(rawResponse);
            result.RequestId = response?.RequestId;
            result.Code = response?.Code;
            result.Message = response?.Message;
            result.BizCode = response?.ResultObject?.BizCode;
            result.Similarity = ParseVerifyScore(response?.ResultObject?.FaceDetail);
            result.Passed = response?.ResultObject?.BizCode switch
            {
                "1" => true,
                "2" or "3" => false,
                _ => null
            };
        }
        catch
        {
            result.Message = "阿里云响应不是合法JSON";
        }

        return result;
    }

    private static double? ParseVerifyScore(string faceDetail)
    {
        if (string.IsNullOrWhiteSpace(faceDetail))
        {
            return null;
        }

        var detail = JsonConvert.DeserializeObject<AliyunId3MetaVerifyFaceDetail>(faceDetail);
        return detail?.VerifyScore;
    }

    private static string ComputeSignature(SortedDictionary<string, string> parameters, string httpMethod, string accessKeySecret)
    {
        var canonicalized = new StringBuilder();
        foreach (var kv in parameters)
        {
            if (kv.Key == "Signature")
            {
                continue;
            }

            if (canonicalized.Length > 0)
            {
                canonicalized.Append('&');
            }

            canonicalized.Append(PercentEncode(kv.Key))
                .Append('=')
                .Append(PercentEncode(kv.Value));
        }

        var stringToSign = httpMethod + "&" + PercentEncode("/") + "&" + PercentEncode(canonicalized.ToString());
        var signKey = accessKeySecret + "&";
        using var hmac = new HMACSHA1(Encoding.UTF8.GetBytes(signKey));
        var hash = hmac.ComputeHash(Encoding.UTF8.GetBytes(stringToSign));
        return Convert.ToBase64String(hash);
    }

    private static string BuildBodyString(SortedDictionary<string, string> parameters)
    {
        return string.Join("&", parameters
            .Where(x => x.Key != "Signature")
            .Select(x => PercentEncode(x.Key) + "=" + PercentEncode(x.Value)));
    }

    private static string PercentEncode(string value)
    {
        if (string.IsNullOrEmpty(value))
        {
            return string.Empty;
        }

        return Uri.EscapeDataString(value)
            .Replace("+", "%20")
            .Replace("*", "%2A")
            .Replace("%7E", "~");
    }

    private class AliyunId3MetaVerifyApiResponse
    {
        public string RequestId { get; set; }

        public string Message { get; set; }

        public string Code { get; set; }

        public AliyunId3MetaVerifyResultObject ResultObject { get; set; }
    }

    private class AliyunId3MetaVerifyResultObject
    {
        public string BizCode { get; set; }

        public string FaceDetail { get; set; }
    }

    private class AliyunId3MetaVerifyFaceDetail
    {
        [JsonProperty("verifyScore")]
        public double? VerifyScore { get; set; }
    }
}