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">日志配置请求</param>
        /// <returns>操作结果</returns>
        [HttpPost("clients/{clientName}/logs-config")]
        public ActionResult SetClientLogsConfig(string clientName, [FromBody] LogsConfigRequest request)
        {
            var success = _webSocketManager.SetClientLogsConfig(clientName, request.Config, request.Save);
            if (success)
                return Ok(new { message = $"客户端 '{clientName}' 日志配置已更新" });
            else
                return BadRequest($"更新客户端 '{clientName}' 日志配置失败");
        }

        /// <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)
        {
            Response.ContentType = "text/event-stream";
            Response.Headers.Add("Cache-Control", "no-cache");
            Response.Headers.Add("Connection", "keep-alive");

            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" });
                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" });

            int sentIndex = 0;
            int receivedIndex = 0;
            var cancellationToken = HttpContext.RequestAborted;

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

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

                // 检查并高效地发送新的"已接收"消息
                if (client.ReceivedMessagesCount > receivedIndex)
                {
                    var newMessages = client.ReceivedMessages.Skip(receivedIndex).ToList();
                    if (newMessages.Any())
                    {
                        await SendSseEvent("update", new { type = "received", messages = newMessages, totalCount = client.ReceivedMessagesCount });
                        receivedIndex = client.ReceivedMessagesCount;
                        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
            }
        }

        private async Task SendSseEvent(string eventName, object data)
        {
            var json = Newtonsoft.Json.JsonConvert.SerializeObject(data);
            await Response.WriteAsync($"event: {eventName}\n");
            await Response.WriteAsync($"data: {json}\n\n");
        }

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

            int logIndex = 0;

            // 首先，一次性推送所有已缓存的日志
            var initialLogs = _webSocketManager.GetLogCache().ToList();
            if (initialLogs.Any())
            {
                await SendSseEvent("history", new { logs = initialLogs });
                await Response.Body.FlushAsync(cancellationToken);
                logIndex = initialLogs.Count;
            }

            while (!cancellationToken.IsCancellationRequested)
            {
                var logCache = _webSocketManager.GetLogCache();
                if (logCache.Count() > logIndex)
                {
                    var newLogs = logCache.Skip(logIndex).ToList();
                    if (newLogs.Any())
                    {
                        await SendSseEvent("new_logs", new { logs = newLogs });
                        await Response.Body.FlushAsync(cancellationToken);
                        logIndex = logCache.Count();
                    }
                }
                await Task.Delay(250, cancellationToken);
            }
        }
    }

    /// <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;
    }
}