using AutoMapper;
using Kean.Domain.Task.Commands;
using Kean.Domain.Task.Enums;
using Kean.Domain.Task.Events;
using Kean.Domain.Task.Models;
using Kean.Domain.Task.Repositories;
using Kean.Domain.Task.SharedServices.Proxies;
using Kean.Infrastructure.Configuration;
using System;
using System.Linq;
using System.Threading;

namespace Kean.Domain.Task.CommandHandlers
{
    /// <summary>
    /// 创建移库命令处理程序
    /// </summary>
    public sealed class TransferCommandHandler : CommandHandler<TransferCommand>
    {
        private readonly ICommandBus _commandBus; // 命令总线
        private readonly INotification _notifications; // 总线通知
        private readonly IMapper _mapper; // 模型映射
        private readonly ITaskRepository _taskRepository; // 任务仓库
        private readonly IWarehouseRepository _warehouseRepository; // 库房仓库
        private readonly BarcodeInterpreter _barcodeInterpreter; // 条码解释器
        private readonly BarcodeValidator _barcodeValidator; // 条码验证器
        private readonly StockProxy _stockProxy; // 仓储域代理

        /// <summary>
        /// 依赖注入
        /// </summary>
        public TransferCommandHandler(
            ICommandBus commandBus,
            INotification notifications,
            IMapper mapper,
            ITaskRepository taskRepository,
            IWarehouseRepository warehouseRepository,
            BarcodeInterpreter barcodeInterpreter,
            BarcodeValidator barcodeValidator,
            StockProxy stockProxy)
        {
            _commandBus = commandBus;
            _notifications = notifications;
            _mapper = mapper;
            _taskRepository = taskRepository;
            _warehouseRepository = warehouseRepository;
            _barcodeInterpreter = barcodeInterpreter;
            _barcodeValidator = barcodeValidator;
            _stockProxy = stockProxy;
        }

        /// <summary>
        /// 处理程序
        /// </summary>
        public override async System.Threading.Tasks.Task Handle(TransferCommand command, CancellationToken cancellationToken)
        {
            if (command.ValidationResult.IsValid)
            {
                // 条码格式校验
                if (!await _barcodeValidator.Validate(command.Barcode))
                {
                    await _commandBus.Notify(nameof(command.Barcode), "条码格式不正确", command.Barcode,
                            cancellationToken: cancellationToken);
                    return;
                }
                // 任务重复
                if (await _taskRepository.HasTask(command.Barcode))
                {
                    await _commandBus.Notify(nameof(command.Barcode), "托盘正在执行任务", command.Barcode,
                            cancellationToken: cancellationToken);
                    return;
                }
                var pallet = await _barcodeInterpreter.Interpret(command.Barcode);
                // 获取库存位置
                var cell = await _stockProxy.GetCell(command.Barcode);
                if (!cell.HasValue)
                {
                    await _commandBus.Notify(nameof(command.Barcode), "库存不存在", command.Barcode,
                        cancellationToken: cancellationToken);
                    return;
                }
                var original = await _warehouseRepository.GetCellById(cell.Value);
                // 可用的货位
                if (original.State != CellState.Enabled)
                {
                    await _commandBus.Notify(nameof(command.Barcode), "库存位置不合法", command.Barcode,
                        cancellationToken: cancellationToken);
                    return;
                }
                // 获取目标位置
                var destination = command.Destination switch
                {
                    int i => await _warehouseRepository.GetCellById(i),
                    long i => await _warehouseRepository.GetCellById((int)i),
                    string s when s.StartsWith("name:") => await _warehouseRepository.GetCellByName(s[5..], command.Warehouse),
                    string s when s.StartsWith("device:") => await _warehouseRepository.GetCellByDevice(s[7..], command.Warehouse),
                    Cell c => c,
                    _ => null
                };
                // 目标位置可用性
                if (destination?.Warehouse != command.Warehouse
                    || destination.State != CellState.Enabled
                    || destination.IsEmpty == false
                    || destination.Pallet?.Contains(pallet) == false
                    || destination.Spec?.Adaptive(await _stockProxy.GetSpec(command.Barcode) ?? original.Spec) == false)
                {
                    await _commandBus.Notify(nameof(command.Destination), "目标位置不正确", command.Destination,
                            cancellationToken: cancellationToken);
                    return;
                }
                // 时间戳
                command.Timestamp ??= DateTime.Now;
                // 切点事件
                var event0 = _mapper.Map<TransferExecutingEvent>(command);
                event0.Original = original;
                event0.Destination = destination;
                await _commandBus.Trigger(event0, cancellationToken);
                if (!_notifications.Any())
                {
                    // 锁定库存位置和目标位置
                    await _warehouseRepository.LockCell(original.Id, destination.Id);
                    // 非手动模式下的双深避让处理
                    if (!command.Manual)
                    {
                        var avert = new AvertCommand
                        {
                            Cell = original,
                            Behavior = AvertCommand.Leaving,
                            Priority = command.Priority,
                            Previous = command.Previous,
                            Timestamp = command.Timestamp
                        };
                        await _commandBus.Execute(avert, cancellationToken);
                        if (_notifications.Any())
                        {
                            return;
                        }
                        if (avert.Id.HasValue)
                        {
                            command.Previous = avert.Id;
                        }
                        else
                        {
                            avert = new AvertCommand
                            {
                                Cell = destination,
                                Behavior = AvertCommand.Entering,
                                Priority = command.Priority,
                                Previous = command.Previous,
                                Timestamp = command.Timestamp
                            };
                            await _commandBus.Execute(avert, cancellationToken);
                            if (_notifications.Any())
                            {
                                return;
                            }
                            if (avert.Id.HasValue)
                            {
                                command.Previous = avert.Id;
                            }
                        }
                    }
                    // 创建任务
                    var task = _mapper.Map<Models.Task>(command);
                    task.Type = TaskType.Transfer;
                    task.Original = original.Id;
                    task.Destination = destination.Id;
                    Output(nameof(command.Id), await _taskRepository.CreateTask(task));
                    // 成功事件
                    var event1 = _mapper.Map<TransferSuccessEvent>(command);
                    event1.Original = original;
                    event1.Destination = destination;
                    await _commandBus.Trigger(event1, cancellationToken);
                    // 手动
                    if (command.Manual && !_notifications.Any())
                    {
                        await _commandBus.Execute(new CompleteCommand { Id = command.Id }, cancellationToken);
                    }
                }
            }
            else
            {
                await _commandBus.Notify(command.ValidationResult,
                    cancellationToken: cancellationToken);
            }
        }
    }
}