using DbusSmsForward.Helper;
using DbusSmsForward.Services;
using DbusSmsForward.SettingModel;
using DbusSmsForward.SMSModel;
using System.Security.Cryptography;
using System.Text;
using System.Text.Json.Nodes;
using System.Web;

namespace DbusSmsForward.Notifications;

public sealed class DingTalkNotificationSender(DbusSmsForwardOptions options) : NotificationSenderBase("dingtalk")
{
    private readonly DingTalkConfig _config = options.Notifications.DingTalk;

    public override bool IsEnabled => _config.Enabled && !string.IsNullOrWhiteSpace(_config.AccessToken);

    public override async Task SendAsync(SmsContentModel sms, string body, string deviceName, CancellationToken cancellationToken)
    {
        string url = $"{_config.Endpoint}?access_token={HttpUtility.UrlEncode(_config.AccessToken)}";
        if (!string.IsNullOrWhiteSpace(_config.Secret))
        {
            long timestamp = DateTimeOffset.UtcNow.ToUnixTimeMilliseconds();
            string sign = AddSign(timestamp, _config.Secret);
            url += $"&timestamp={timestamp}&sign={sign}";
        }

        JsonObject payload = new()
        {
            ["msgtype"] = "text",
            ["text"] = new JsonObject
            {
                ["content"] = body
            }
        };

        await HttpHelper.PostAsync(url, payload, _config.SkipTlsValidation, cancellationToken);
    }

    private static string AddSign(long timestamp, string secret)
    {
        string stringToSign = $"{timestamp}\n{secret}";
        using HMACSHA256 hmacsha256 = new(Encoding.UTF8.GetBytes(secret));
        byte[] hashmessage = hmacsha256.ComputeHash(Encoding.UTF8.GetBytes(stringToSign));
        return HttpUtility.UrlEncode(Convert.ToBase64String(hashmessage), Encoding.UTF8);
    }
}