using System.Collections.Concurrent;
using Sln.Wcs.Model.Domain;
using Sln.Wcs.Repository.service;
using Sln.Wcs.Serilog;

namespace Sln.Wcs.Strategy;

/// <summary>
/// 包材入库任务执行器 (taskCategory=1, taskType=1)
/// 轮询待执行任务 → 多任务并行、单任务内串行逐条下发明细
/// </summary>
public class MaterialInStoreExecutor
{
    private readonly SerilogHelper _logger;
    private readonly ILiveTaskQueueService _taskQueueService;
    private readonly ILiveTaskDetailService _taskDetailService;

    // 每栋楼提升机限 2 台并发，AGV 不限
    private static readonly ConcurrentDictionary<int, SemaphoreSlim> HoistSemaphores = new();

    // DB 写操作互斥锁（SqlSugar Context 共享导致写入不能并发）
    private static readonly object DbWriteLock = new();

    // 最大同时执行任务数
    private static readonly SemaphoreSlim TaskSemaphore = new(10, 10);

    private readonly object _lock = new();
    private CancellationTokenSource? _cts;
    private volatile bool _isRunning;

    public bool IsRunning => _isRunning;

    public MaterialInStoreExecutor(
        SerilogHelper logger,
        ILiveTaskQueueService taskQueueService,
        ILiveTaskDetailService taskDetailService)
    {
        _logger = logger;
        _taskQueueService = taskQueueService;
        _taskDetailService = taskDetailService;
    }

    public void Start()
    {
        lock (_lock)
        {
            if (_isRunning) return;
            _cts = new CancellationTokenSource();
            _isRunning = true;
        }
        Task.Run(() => RunLoopAsync(_cts!.Token));
        _logger.Info("包材入库调度已启动");
    }

    public void Stop()
    {
        CancellationTokenSource? cts;
        lock (_lock)
        {
            if (!_isRunning) return;
            cts = _cts;
            _isRunning = false;
        }
        cts?.Cancel();
        _logger.Info("包材入库调度已停止");
    }

    private async Task RunLoopAsync(CancellationToken ct)
    {
        while (!ct.IsCancellationRequested)
        {
            try { await Task.Run(() => ExecuteAsync(ct), ct); }
            catch (OperationCanceledException) { break; }
            catch (Exception ex) { _logger.Error($"调度异常: {ex.Message}"); }

            try { await Task.Delay(5000, ct); }
            catch (OperationCanceledException) { break; }
        }
    }

    private void ExecuteAsync(CancellationToken ct)
    {
        var tasks = _taskQueueService.getLiveTaskQueues(x =>
            x.taskType == 1 && x.taskCategory == 1 && x.taskStatus == 1);

        if (tasks.Count == 0) return;

        _logger.Info($"查询到 {tasks.Count} 条待执行包材入库任务");

        var threads = new List<Thread>();
        foreach (var task in tasks)
        {
            var captured = task;
            var t = new Thread(() =>
            {
                TaskSemaphore.Wait();
                try
                {
                    if (ct.IsCancellationRequested) return;
                    _logger.Info($"[线程启动] {captured.taskCode}");
                    ProcessOneAsync(captured, ct).GetAwaiter().GetResult();
                }
                catch (Exception ex) { _logger.Error($"任务 {captured.taskCode} 线程异常: {ex.Message}"); }
                finally { TaskSemaphore.Release(); }
            })
            { IsBackground = true };
            t.Start();
            threads.Add(t);
        }

        foreach (var t in threads)
            t.Join();
    }

    private async Task ProcessOneAsync(LiveTaskQueue task, CancellationToken ct)
    {
        _logger.Info($"开始执行 {task.taskCode}，共 {task.taskDetails.Count} 条明细");

        lock (DbWriteLock) { task.taskStatus = 2; _taskQueueService.Update(task); }

        foreach (var detail in task.taskDetails.OrderBy(d => d.objId))
        {
            if (ct.IsCancellationRequested) return;

            if (detail.taskStatus is 2 or 3)
            {
                _logger.Info($"  明细 {detail.objId} 已处理，跳过");
                continue;
            }

            lock (DbWriteLock) { detail.taskStatus = 2; _taskDetailService.Update(detail); }

            var devName = detail.deviceType switch { 1 => "AGV", 2 => "提升机", _ => "输送线" };
            _logger.Info($"  → {devName}下发 {detail.taskCode}-{detail.objId}: {detail.startPoint} → {detail.endPoint}");

            // 模拟执行在锁外，多任务并行不受影响
            var ok = detail.deviceType switch
            {
                1 => await DispatchAgvAsync(detail),
                2 => await DispatchHoistAsync(detail),
                _ => await DispatchConveyorAsync(detail)
            };

            if (ok)
            {
                lock (DbWriteLock) { detail.taskStatus = 3; _taskDetailService.Update(detail); }
                _logger.Info($"  ✓ {detail.objId} 完成");
            }
            else
            {
                lock (DbWriteLock) { detail.taskStatus = 1; _taskDetailService.Update(detail); }
                _logger.Error($"  ✗ {detail.objId} 失败，中断任务");
                return;
            }
        }

        lock (DbWriteLock) { task.taskStatus = 3; _taskQueueService.Update(task); }
        _logger.Info($"任务 {task.taskCode} 执行完成");
    }

    private async Task<bool> DispatchAgvAsync(LiveTaskDetail detail)
    {
        // AGV 不限并发，直接下发
        _logger.Info($"    [AGV] 开始 {detail.startPoint} → {detail.endPoint}");
        await Task.Delay(10_000); // 模拟执行 10s
        _logger.Info($"    [AGV] 完成 {detail.startPoint} → {detail.endPoint}");
        return true;
    }

    private async Task<bool> DispatchHoistAsync(LiveTaskDetail detail)
    {
        // 每栋楼提升机限 2 台并发
        var building = ExtractBuilding(detail.startPoint);
        var semaphore = HoistSemaphores.GetOrAdd(building, _ => new SemaphoreSlim(2, 2));

        await semaphore.WaitAsync();
        try
        {
            _logger.Info($"    [提升机] {building}#楼 开始 (可用:{semaphore.CurrentCount}) {detail.startPoint} → {detail.endPoint}");
            await Task.Delay(20_000); // 模拟执行 20s
            _logger.Info($"    [提升机] {building}#楼 完成 {detail.startPoint} → {detail.endPoint}");
            return true;
        }
        finally
        {
            semaphore.Release();
        }
    }

    private Task<bool> DispatchConveyorAsync(LiveTaskDetail detail)
    {
        _logger.Info($"    [输送线] {detail.startPoint} → {detail.endPoint}");
        return Task.FromResult(true);
    }

    /// <summary>从接驳位编码中提取楼栋号，如 "13#_L1_HOIST" → 13</summary>
    private static int ExtractBuilding(string pointCode)
    {
        var match = System.Text.RegularExpressions.Regex.Match(pointCode, @"^(\d+)");
        return match.Success ? int.Parse(match.Groups[1].Value) : 0;
    }
}