using Microsoft.AspNetCore.Mvc;
using LTEMvcApp.Models;
using LTEMvcApp.Services;
using Newtonsoft.Json.Linq;
using Microsoft.Extensions.Logging;
using System.Threading.Tasks;
using System.Linq;
using System.Threading;

namespace LTEMvcApp.Controllers
{
    /// <summary>
    /// WebSocket控制器 - 提供LTE客户端WebSocket管理API
    /// </summary>
    [ApiController]
    [Route("api/[controller]")]
    public class WebSocketController : ControllerBase
    {
        private readonly WebSocketManagerService _webSocketManager;
        private readonly ILogger<WebSocketController> _logger;

        public WebSocketController(WebSocketManagerService webSocketManager, ILogger<WebSocketController> logger)
        {
            _webSocketManager = webSocketManager;
            _logger = logger;
        }

        /// <summary>
        /// 获取所有客户端状态
        /// </summary>
        /// <returns>客户端状态列表</returns>
        [HttpGet("clients")]
        public ActionResult<Dictionary<string, ClientState>> GetClientStates()
        {
            _logger.LogInformation("获取所有客户端状态");
            var states = _webSocketManager.GetAllClientStates();
            return Ok(states);
        }

        /// <summary>
        /// 获取客户端配置
        /// </summary>
        /// <param name="clientName">客户端名称</param>
        /// <returns>客户端配置</returns>
        [HttpGet("clients/{clientName}/config")]
        public ActionResult<ClientConfig?> GetClientConfig(string clientName)
        {
            var config = _webSocketManager.GetClientConfig(clientName);
            if (config == null)
                return NotFound($"客户端 '{clientName}' 不存在");

            return Ok(config);
        }

        /// <summary>
        /// 获取所有客户端配置
        /// </summary>
        /// <returns>客户端配置列表</returns>
        [HttpGet("configs")]
        public ActionResult<List<ClientConfig>> GetAllConfigs()
        {
            var configs = _webSocketManager.GetAllClientConfigs();
            return Ok(configs);
        }

        /// <summary>
        /// 添加客户端配置
        /// </summary>
        /// <param name="config">客户端配置</param>
        /// <returns>操作结果</returns>
        [HttpPost("configs")]
        public ActionResult AddClientConfig([FromBody] ClientConfig config)
        {
            if (string.IsNullOrEmpty(config.Name))
                return BadRequest("客户端名称不能为空");

            var success = _webSocketManager.AddClientConfig(config);
            if (success)
                return Ok(new { message = $"客户端 '{config.Name}' 配置已添加" });
            else
                return BadRequest("添加客户端配置失败");
        }

        /// <summary>
        /// 启动客户端
        /// </summary>
        /// <param name="clientName">客户端名称</param>
        /// <returns>操作结果</returns>
        [HttpPost("clients/{clientName}/start")]
        public ActionResult StartClient(string clientName)
        {
            _logger.LogInformation($"API请求: 启动客户端 {clientName}");
            var success = _webSocketManager.StartClient(clientName);
            if (success)
            {
                _logger.LogInformation($"客户端 {clientName} 启动成功");
                return Ok(new { message = $"客户端 '{clientName}' 已启动" });
            }
            else
            {
                _logger.LogWarning($"客户端 {clientName} 启动失败");
                return BadRequest($"启动客户端 '{clientName}' 失败");
            }
        }

        /// <summary>
        /// 停止客户端
        /// </summary>
        /// <param name="clientName">客户端名称</param>
        /// <returns>操作结果</returns>
        [HttpPost("clients/{clientName}/stop")]
        public ActionResult StopClient(string clientName)
        {
            var success = _webSocketManager.StopClient(clientName);
            if (success)
                return Ok(new { message = $"客户端 '{clientName}' 已停止" });
            else
                return BadRequest($"停止客户端 '{clientName}' 失败");
        }

        /// <summary>
        /// 播放/暂停客户端
        /// </summary>
        /// <param name="clientName">客户端名称</param>
        /// <returns>操作结果</returns>
        [HttpPost("clients/{clientName}/playpause")]
        public ActionResult PlayPauseClient(string clientName)
        {
            var success = _webSocketManager.PlayPauseClient(clientName);
            if (success)
                return Ok(new { message = $"客户端 '{clientName}' 播放/暂停状态已切换" });
            else
                return BadRequest($"切换客户端 '{clientName}' 播放/暂停状态失败");
        }

        /// <summary>
        /// 重置客户端日志
        /// </summary>
        /// <param name="clientName">客户端名称</param>
        /// <returns>操作结果</returns>
        [HttpPost("clients/{clientName}/reset-logs")]
        public ActionResult ResetClientLogs(string clientName)
        {
            var success = _webSocketManager.ResetClientLogs(clientName);
            if (success)
                return Ok(new { message = $"客户端 '{clientName}' 日志已重置" });
            else
                return BadRequest($"重置客户端 '{clientName}' 日志失败");
        }

        /// <summary>
        /// 获取客户端日志
        /// </summary>
        /// <param name="clientName">客户端名称</param>
        /// <param name="limit">日志数量限制</param>
        /// <returns>日志列表</returns>
        [HttpGet("clients/{clientName}/logs")]
        public ActionResult<List<LTELog>?> GetClientLogs(string clientName, [FromQuery] int limit = 100)
        {
            var logs = _webSocketManager.GetClientLogs(clientName);
            if (logs == null)
                return NotFound($"客户端 '{clientName}' 不存在或未连接");

            // 限制返回的日志数量
            var limitedLogs = logs.TakeLast(limit).ToList();
            return Ok(limitedLogs);
        }

        /// <summary>
        /// 设置客户端日志配置
        /// </summary>
        /// <param name="clientName">客户端名称</param>
        /// <param name="request">请求体</param>
        [HttpPost("clients/{clientName}/logs-config")]
        public ActionResult SetClientLogsConfig(string clientName, [FromBody] ClientLogsConfig request)
        {
            var success = _webSocketManager.SetClientLogsConfig(clientName, request);
            if (success)
            {
                return Ok(new { message = "日志配置已更新" });
            }
            else
            {
                return NotFound(new { message = $"客户端 '{clientName}' 未找到或更新失败" });
            }
        }

        /// <summary>
        /// 发送消息到客户端
        /// </summary>
        /// <param name="clientName">客户端名称</param>
        /// <param name="message">消息内容</param>
        /// <returns>操作结果</returns>
        [HttpPost("clients/{clientName}/send-message")]
        public ActionResult SendMessage(string clientName, [FromBody] JObject message)
        {
            var messageId = _webSocketManager.SendMessageToClient(clientName, message);
            if (messageId >= 0)
                return Ok(new { messageId, message = $"消息已发送到客户端 '{clientName}'" });
            else
                return BadRequest($"发送消息到客户端 '{clientName}' 失败");
        }

        /// <summary>
        /// 获取连接统计信息
        /// </summary>
        /// <returns>统计信息</returns>
        [HttpGet("statistics")]
        public ActionResult<ConnectionStatistics> GetStatistics()
        {
            var stats = _webSocketManager.GetConnectionStatistics();
            return Ok(stats);
        }

        /// <summary>
        /// 启动所有已配置的客户端
        /// </summary>
        /// <returns>操作结果</returns>
        [HttpPost("start-all")]
        public ActionResult StartAllClients()
        {
            _webSocketManager.StartAllConfiguredClients();
            return Ok(new { message = "所有已配置的客户端已启动" });
        }

        /// <summary>
        /// 停止所有客户端
        /// </summary>
        /// <returns>操作结果</returns>
        [HttpPost("stop-all")]
        public ActionResult StopAllClients()
        {
            _webSocketManager.StopAllClients();
            return Ok(new { message = "所有客户端已停止" });
        }

        /// <summary>
        /// 移除客户端配置
        /// </summary>
        /// <param name="clientName">客户端名称</param>
        /// <returns>操作结果</returns>
        [HttpDelete("configs/{clientName}")]
        public ActionResult RemoveClientConfig(string clientName)
        {
            var success = _webSocketManager.RemoveClientConfig(clientName);
            if (success)
                return Ok(new { message = $"客户端 '{clientName}' 配置已移除" });
            else
                return BadRequest($"移除客户端 '{clientName}' 配置失败");
        }

        /// <summary>
        /// 使用 Server-Sent Events (SSE) 实时推送客户端消息
        /// </summary>
        /// <param name="clientName">客户端名称</param>
        [HttpGet("clients/{clientName}/messages/stream")]
        public async Task StreamClientMessages(string clientName)
        {
            try
            {
                Response.ContentType = "text/event-stream";
                Response.Headers.Append("Cache-Control", "no-cache");
                Response.Headers.Append("Connection", "keep-alive");
                Response.Headers.Append("Access-Control-Allow-Origin", "*");

                var client = _webSocketManager.GetClientInstance(clientName);
                if (client == null)
                {
                    // 发送一个错误事件然后关闭
                    await SendSseEvent("error", new { message = "客户端未连接或不存在", clientName });
                    return;
                }

                // 发送一个连接成功事件
                await SendSseEvent("open", new { 
                    message = "成功连接到服务器事件流", 
                    clientName,
                    timestamp = DateTime.UtcNow 
                });
                await Response.Body.FlushAsync(HttpContext.RequestAborted);

                int lastSentCount = 0;
                int lastReceivedCount = 0;
                var cancellationToken = HttpContext.RequestAborted;

                while (!cancellationToken.IsCancellationRequested)
                {
                    try
                    {
                        bool hasNewMessages = false;

                        // 检查并高效地发送新的"已发送"消息
                        var currentSentCount = client.SentMessagesCount;
                        if (currentSentCount > lastSentCount)
                        {
                            var sentMessages = client.SentMessages?.ToList() ?? new List<string>();
                            if (sentMessages.Count > lastSentCount)
                            {
                                var newMessages = sentMessages.Skip(lastSentCount).ToList();
                                if (newMessages.Any())
                                {
                                    await SendSseEvent("update", new { 
                                        type = "sent", 
                                        messages = newMessages, 
                                        totalCount = currentSentCount,
                                        newCount = newMessages.Count 
                                    });
                                    lastSentCount = currentSentCount;
                                    hasNewMessages = true;
                                }
                            }
                        }

                        // 检查并高效地发送新的"已接收"消息
                        var currentReceivedCount = client.ReceivedMessagesCount;
                        if (currentReceivedCount > lastReceivedCount)
                        {
                            var receivedMessages = client.ReceivedMessages?.ToList() ?? new List<string>();
                            if (receivedMessages.Count > lastReceivedCount)
                            {
                                var newMessages = receivedMessages.Skip(lastReceivedCount).ToList();
                                if (newMessages.Any())
                                {
                                    await SendSseEvent("update", new { 
                                        type = "received", 
                                        messages = newMessages, 
                                        totalCount = currentReceivedCount,
                                        newCount = newMessages.Count 
                                    });
                                    lastReceivedCount = currentReceivedCount;
                                    hasNewMessages = true;
                                }
                            }
                        }

                        if (hasNewMessages)
                        {
                            await Response.Body.FlushAsync(cancellationToken);
                        }

                        await Task.Delay(250, cancellationToken); // 每250毫秒检查一次新消息
                    }
                    catch (OperationCanceledException)
                    {
                        // 正常的取消操作，退出循环
                        break;
                    }
                    catch (Exception ex)
                    {
                        _logger.LogError(ex, "StreamClientMessages 循环中发生错误，客户端: {ClientName}", clientName);
                        await SendSseEvent("error", new { 
                            message = "处理消息流时发生错误", 
                            error = ex.Message,
                            clientName,
                            timestamp = DateTime.UtcNow 
                        });
                        await Response.Body.FlushAsync(cancellationToken);
                        
                        // 等待一段时间后继续，避免频繁错误
                        await Task.Delay(1000, cancellationToken);
                    }
                }

                // 发送断开连接事件
                await SendSseEvent("disconnected", new { 
                    message = "客户端消息流连接已断开", 
                    clientName,
                    timestamp = DateTime.UtcNow 
                });
                await Response.Body.FlushAsync(cancellationToken);
            }
            catch (OperationCanceledException)
            {
                _logger.LogInformation("StreamClientMessages 连接被客户端取消，客户端: {ClientName}", clientName);
            }
            catch (Exception ex)
            {
                _logger.LogError(ex, "StreamClientMessages 方法执行时发生未处理的异常，客户端: {ClientName}", clientName);
                try
                {
                    await SendSseEvent("fatal_error", new { 
                        message = "服务器内部错误", 
                        error = ex.Message,
                        clientName,
                        timestamp = DateTime.UtcNow 
                    });
                    await Response.Body.FlushAsync();
                }
                catch
                {
                    // 忽略发送错误事件时的异常
                }
            }
        }

        private async Task SendSseEvent(string eventName, object data)
        {
            try
            {
                if (string.IsNullOrEmpty(eventName))
                {
                    _logger.LogWarning("尝试发送空事件名称的SSE事件");
                    return;
                }

                if (data == null)
                {
                    _logger.LogWarning("尝试发送空数据的SSE事件: {EventName}", eventName);
                    return;
                }

                var json = Newtonsoft.Json.JsonConvert.SerializeObject(data);
                var eventData = $"event: {eventName}\ndata: {json}\n\n";
                
                await Response.WriteAsync(eventData);
            }
            catch (Exception ex)
            {
                _logger.LogError(ex, "发送SSE事件时发生错误: {EventName}", eventName);
                // 不重新抛出异常，避免影响整个流
            }
        }

        /// <summary>
        /// 获取测试客户端配置
        /// </summary>
        /// <returns>测试客户端配置</returns>
        [HttpGet("test-client-config")]
        public ActionResult<ClientConfig> GetTestClientConfig()
        {
            var testConfig = _webSocketManager.GetTestClientConfig();
            return Ok(testConfig);
        }

        /// <summary>
        /// 设置测试客户端配置
        /// </summary>
        /// <param name="config">测试客户端配置</param>
        /// <returns>操作结果</returns>
        [HttpPost("test-client-config")]
        public ActionResult SetTestClientConfig([FromBody] ClientConfig config)
        {
            if (string.IsNullOrEmpty(config.Name))
                return BadRequest("客户端名称不能为空");

            var success = _webSocketManager.SetTestClientConfig(config);
            if (success)
                return Ok(new { message = "测试客户端配置已更新" });
            else
                return BadRequest("更新测试客户端配置失败");
        }

        /// <summary>
        /// 启动测试客户端
        /// </summary>
        /// <returns>操作结果</returns>
        [HttpPost("test-client/start")]
        public ActionResult StartTestClient()
        {
            var success = _webSocketManager.StartTestClient();
            if (success)
                return Ok(new { message = "测试客户端已启动" });
            else
                return BadRequest("启动测试客户端失败");
        }

        /// <summary>
        /// 停止测试客户端
        /// </summary>
        /// <returns>操作结果</returns>
        [HttpPost("test-client/stop")]
        public ActionResult StopTestClient()
        {
            _logger.LogInformation("API 请求: 停止测试客户端");
            var success = _webSocketManager.StopTestClient();
            if (success)
                return Ok(new { message = "测试客户端停止成功" });
            else
                return BadRequest("停止测试客户端失败");
        }

        /// <summary>
        /// 获取日志缓存统计信息
        /// </summary>
        /// <returns>统计信息</returns>
        [HttpGet("logs/stats")]
        public ActionResult<object> GetLogCacheStats()
        {
            try
            {
                var stats = new
                {
                    totalLogs = _webSocketManager.GetLogCacheCount(),
                    cacheSize = 10000, // LogCacheSize
                    timestamp = DateTime.UtcNow
                };
                return Ok(stats);
            }
            catch (Exception ex)
            {
                _logger.LogError(ex, "获取日志缓存统计信息时发生错误");
                return StatusCode(500, new { message = "获取统计信息失败", error = ex.Message });
            }
        }

        /// <summary>
        /// 清空全局日志缓存
        /// </summary>
        /// <returns>操作结果</returns>
        [HttpPost("logs/clear")]
        public ActionResult ClearLogCache()
        {
            try
            {
                _webSocketManager.ClearLogCache();
                return Ok(new { message = "日志缓存已清空" });
            }
            catch (Exception ex)
            {
                _logger.LogError(ex, "清空日志缓存时发生错误");
                return StatusCode(500, new { message = "清空日志缓存失败", error = ex.Message });
            }
        }

        /// <summary>
        /// 重置全局日志缓存
        /// </summary>
        /// <returns>操作结果</returns>
        [HttpPost("logs/reset")]
        public ActionResult ResetLogCache()
        {
            try
            {
                _webSocketManager.ResetLogCache();
                return Ok(new { message = "日志缓存已重置" });
            }
            catch (Exception ex)
            {
                _logger.LogError(ex, "重置日志缓存时发生错误");
                return StatusCode(500, new { message = "重置日志缓存失败", error = ex.Message });
            }
        }

        /// <summary>
        /// 添加测试日志数据
        /// </summary>
        /// <returns>操作结果</returns>
        [HttpPost("logs/add-test-data")]
        public ActionResult AddTestLogData()
        {
            try
            {
                var testLogs = new List<LTELog>
                {
                  
                };

                // 手动添加到日志缓存
                _webSocketManager.AddLogsToCache(testLogs);

                return Ok(new { message = $"已添加 {testLogs.Count} 条测试日志" });
            }
            catch (Exception ex)
            {
                _logger.LogError(ex, "添加测试日志数据时发生错误");
                return StatusCode(500, new { message = "添加测试日志失败", error = ex.Message });
            }
        }

        /// <summary>
        /// 使用 Server-Sent Events (SSE) 实时推送全局日志
        /// </summary>
        [HttpGet("logs/stream")]
        public async Task StreamLogs(CancellationToken cancellationToken)
        {
            try
            {
                Response.ContentType = "text/event-stream";
                Response.Headers.Append("Cache-Control", "no-cache");
                Response.Headers.Append("Connection", "keep-alive");
                Response.Headers.Append("Access-Control-Allow-Origin", "*");

                // 发送连接成功事件
                await SendSseEvent("connected", new { message = "日志流连接已建立", timestamp = DateTime.UtcNow });
                await Response.Body.FlushAsync(cancellationToken);

                int lastLogCount = 0;
                var lastLogs = new List<LTELog>();

                // 首先，一次性推送所有已缓存的日志
                try
                {
                    var initialLogs = _webSocketManager.GetLogCache()?.ToList() ?? new List<LTELog>();
                    _logger.LogInformation("StreamLogs: 获取到初始日志 {Count} 条", initialLogs.Count);
                    
                    if (initialLogs.Any())
                    {
                        _logger.LogInformation("StreamLogs: 发送历史日志事件，日志数量: {Count}", initialLogs.Count);
                        await SendSseEvent("history", new { logs = initialLogs, totalCount = initialLogs.Count });
                        await Response.Body.FlushAsync(cancellationToken);
                        lastLogCount = initialLogs.Count;
                        lastLogs = initialLogs.ToList(); // 保存副本用于比较
                    }
                    else
                    {
                        _logger.LogInformation("StreamLogs: 没有历史日志数据");
                    }
                }
                catch (Exception ex)
                {
                    _logger.LogError(ex, "获取初始日志时发生错误");
                    await SendSseEvent("error", new { message = "获取初始日志失败", error = ex.Message });
                    await Response.Body.FlushAsync(cancellationToken);
                }

                while (!cancellationToken.IsCancellationRequested)
                {
                    try
                    {
                        var currentLogs = _webSocketManager.GetLogCache()?.ToList() ?? new List<LTELog>();
                        
                        // 检查是否有新日志
                        if (currentLogs.Count > lastLogCount)
                        {
                            // 计算新增的日志
                            var newLogs = currentLogs.Skip(lastLogCount).ToList();
                            
                            if (newLogs.Any())
                            {
                                _logger.LogInformation("StreamLogs: 发送新日志事件，新增日志数量: {NewCount}, 总日志数量: {TotalCount}", newLogs.Count, currentLogs.Count);
                                await SendSseEvent("new_logs", new { 
                                    logs = newLogs, 
                                    totalCount = currentLogs.Count,
                                    newCount = newLogs.Count 
                                });
                                await Response.Body.FlushAsync(cancellationToken);
                                
                                // 更新索引和缓存
                                lastLogCount = currentLogs.Count;
                                lastLogs = currentLogs.ToList();
                            }
                        }
                        else if (currentLogs.Count < lastLogCount)
                        {
                            // 日志被清空或重置的情况
                            _logger.LogInformation("检测到日志缓存被重置，重新同步");
                            await SendSseEvent("reset", new { 
                                message = "日志缓存已重置",
                                totalCount = currentLogs.Count 
                            });
                            await Response.Body.FlushAsync(cancellationToken);
                            
                            lastLogCount = currentLogs.Count;
                            lastLogs = currentLogs.ToList();
                        }

                        await Task.Delay(250, cancellationToken);
                    }
                    catch (OperationCanceledException)
                    {
                        // 正常的取消操作，退出循环
                        break;
                    }
                    catch (Exception ex)
                    {
                        _logger.LogError(ex, "StreamLogs 循环中发生错误");
                        await SendSseEvent("error", new { 
                            message = "处理日志流时发生错误", 
                            error = ex.Message,
                            timestamp = DateTime.UtcNow 
                        });
                        await Response.Body.FlushAsync(cancellationToken);
                        
                        // 等待一段时间后继续，避免频繁错误
                        await Task.Delay(1000, cancellationToken);
                    }
                }

                // 发送断开连接事件
                await SendSseEvent("disconnected", new { 
                    message = "日志流连接已断开", 
                    timestamp = DateTime.UtcNow 
                });
                await Response.Body.FlushAsync(cancellationToken);
            }
            catch (OperationCanceledException)
            {
                _logger.LogInformation("StreamLogs 连接被客户端取消");
            }
            catch (Exception ex)
            {
                _logger.LogError(ex, "StreamLogs 方法执行时发生未处理的异常");
                try
                {
                    await SendSseEvent("fatal_error", new { 
                        message = "服务器内部错误", 
                        error = ex.Message,
                        timestamp = DateTime.UtcNow 
                    });
                    await Response.Body.FlushAsync();
                }
                catch
                {
                    // 忽略发送错误事件时的异常
                }
            }
        }
    }

    /// <summary>
    /// 日志配置请求
    /// </summary>
    public class LogsConfigRequest
    {
        /// <summary>
        /// 日志配置
        /// </summary>
        public Dictionary<string, object> Config { get; set; } = new();

        /// <summary>
        /// 是否保存配置
        /// </summary>
        public bool Save { get; set; } = false;
    }
}