using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using CoreAgent.ProtocolClient.Models;
using Microsoft.Extensions.Logging;
using Newtonsoft.Json.Linq;

namespace CoreAgent.ProtocolClient.ProtocolEngineCore
{
    /// <summary>
    /// 管理客户端的认证过程
    /// 职责：
    /// 1. 处理 "authenticate" 消息响应。
    /// 2. 根据服务器的 challenge 发起认证请求。
    /// 3. 维护和提供认证状态 (IsAuthenticated)。
    /// 4. 在认证成功后触发事件通知。
    /// </summary>
    public class AuthenticationManager
    {
        private readonly ProtocolClientConfig _config;
        private readonly ILogger _logger;
        private readonly Action<JObject> _sendMessage;
        private bool _isAuthenticated = false;

        public bool IsAuthenticated => _isAuthenticated;

        public event EventHandler? Authenticated;

        public AuthenticationManager(ProtocolClientConfig config, ILogger logger, Action<JObject> sendMessage)
        {
            _config = config;
            _logger = logger;
            _sendMessage = sendMessage;
        }

        /// <summary>
        /// 处理收到的认证相关消息。
        /// </summary>
        public void HandleMessage(JObject message)
        {
            var messageType = message["message"]?.ToString();
            if (messageType != "authenticate" && messageType != "ready")
            {
                return;
            }

            if (_isAuthenticated) return;

            switch (messageType)
            {
                case "authenticate":
                    if (message["ready"]?.Value<bool>() == true)
                    {
                        OnAuthenticationSuccess();
                    }
                    else if (message["error"] == null && !string.IsNullOrEmpty(_config.Password))
                    {
                        var challenge = message["challenge"]?.ToString() ?? "";
                        PerformAuthentication(challenge);
                    }
                    else
                    {
                        _logger.LogError($"[{_config.Name}] 认证失败: {message["error"]}");
                    }
                    break;
                case "ready":
                    _logger.LogInformation($"[{_config.Name}] 直接收到ready消息，视为认证成功");
                    OnAuthenticationSuccess();
                    break;
            }
        }

        /// <summary>
        /// 当收到 "ready" 消息或认证成功时调用，标记为已认证并触发事件。
        /// </summary>
        public void HandleReadyMessage()
        {
            if (!_isAuthenticated)
            {
                _logger.LogInformation($"[{_config.Name}] 收到 ready 消息，完成认证");
                OnAuthenticationSuccess();
            }
        }

        private void PerformAuthentication(string challenge)
        {
            var authMessage = new JObject
            {
                ["message"] = "authenticate",
                ["password"] = _config.Password,
                ["challenge"] = challenge
            };
            _sendMessage(authMessage);
        }

        private void OnAuthenticationSuccess()
        {
            _logger.LogInformation($"[{_config.Name}] 认证成功");
            _isAuthenticated = true;
            Authenticated?.Invoke(this, EventArgs.Empty);
        }

        public void Reset()
        {
            _isAuthenticated = false;
        }
    }
}