using System.Text;
using YD_Event.Application.Auth;
using YD_Event.Application.Order.Dtos;
using YD_Event.Core.Entities;
using YD_Event.Core.Enum;
using YD_Event.Application.Refund;

namespace YD_Event.Application.Order;

/// <summary>
/// 订单管理服务
/// </summary>
public class OrderService : BaseService<YD_Event.Core.Entities.Order>, ITransient
{
    private readonly ISqlSugarRepository<YD_Event.Core.Entities.Order> _orderRepository;
    private readonly ISqlSugarRepository<EventRegistration> _registrationRepository;
    private readonly ISqlSugarRepository<EventRegistrationItem> _itemRepository;
    private readonly ISqlSugarRepository<EventRegistrationPerson> _personRepository;
    private readonly ISqlSugarRepository<EventRegistrationPayment> _paymentRepository;
    private readonly ISqlSugarRepository<EventInfo> _eventRepository;
    private readonly ISqlSugarRepository<YD_Event.Core.Entities.Merchant> _merchantRepository;
    private readonly RefundConfigService _refundConfigService;
    private readonly IIdGenerator _idGenerator;
    private readonly AuthManager _authManager;

    public OrderService(
        ISqlSugarRepository<YD_Event.Core.Entities.Order> orderRepository,
        ISqlSugarRepository<EventRegistration> registrationRepository,
        ISqlSugarRepository<EventRegistrationItem> itemRepository,
        ISqlSugarRepository<EventRegistrationPerson> personRepository,
        ISqlSugarRepository<EventRegistrationPayment> paymentRepository,
        ISqlSugarRepository<EventInfo> eventRepository,
        ISqlSugarRepository<YD_Event.Core.Entities.Merchant> merchantRepository,
        RefundConfigService refundConfigService,
        IIdGenerator idGenerator,
        AuthManager authManager) : base(orderRepository)
    {
        _orderRepository = orderRepository;
        _registrationRepository = registrationRepository;
        _itemRepository = itemRepository;
        _personRepository = personRepository;
        _paymentRepository = paymentRepository;
        _eventRepository = eventRepository;
        _merchantRepository = merchantRepository;
        _refundConfigService = refundConfigService;
        _idGenerator = idGenerator;
        _authManager = authManager;
    }

    /// <summary>
    /// 创建订单
    /// </summary>
    [DisplayName("创建订单")]
    [HttpPost("create")]
    [UnitOfWork]
    public async Task<string> Create(CreateOrderInput input)
    {
        // 1. Create Registration
        var entity = input.Adapt<EventRegistration>();
        entity.Id = _idGenerator.NextId();
        entity.OrderNo = DateTime.Now.ToString("yyyyMMdd") + new Random().Next(1000, 9999); // Simple generation
        entity.RegistrationStatus = 0; // Pending
        entity.PaymentStatus = 0; // Unpaid
        entity.RegistrationTime = DateTime.Now;

        // Calculate Total
        decimal totalAmount = 0;
        int totalPerson = 0;
        if (input.Items != null)
        {
            foreach (var item in input.Items)
            {
                totalAmount += item.UnitPrice * item.PersonCount;
                totalPerson += item.PersonCount;
            }
        }
        entity.TotalAmount = totalAmount;
        entity.TotalPersonCount = totalPerson;

        await _registrationRepository.InsertAsync(entity);

        // 2. Create Items
        var createdItems = new List<EventRegistrationItem>();
        if (input.Items != null && input.Items.Any())
        {
            var items = input.Items.Adapt<List<EventRegistrationItem>>();
            items.ForEach(x =>
            {
                x.Id = _idGenerator.NextId();
                x.RegistrationId = entity.Id;
                x.TotalPrice = x.UnitPrice * x.PersonCount;
            });
            await _itemRepository.InsertRangeAsync(items);
            createdItems = items;
        }

        // 3. Create Persons
        if (input.Persons != null && input.Persons.Any())
        {
            var persons = input.Persons.Adapt<List<EventRegistrationPerson>>();
            persons.ForEach(x =>
            {
                x.Id = _idGenerator.NextId();
                x.RegistrationId = entity.Id;
                
                // Link to Item based on ProjectId and GroupName
                var linkedItem = createdItems.FirstOrDefault(i => i.ProjectId == x.ProjectId && i.GroupName == x.GroupName);
                if (linkedItem != null)
                {
                    x.RegistrationItemId = linkedItem.Id;
                }
                
                // Ensure GroupName is not null (DB Constraint)
                if (string.IsNullOrEmpty(x.GroupName)) x.GroupName = "";
            });
            await _personRepository.InsertRangeAsync(persons);
        }

        // 4. Create Order (Income)
        // 获取赛事关联的商户ID
        var eventInfo = await _eventRepository.GetByIdAsync(input.EventId);
        
        var order = new YD_Event.Core.Entities.Order
        {
            Id = _idGenerator.NextId(),
            OrderNo = entity.OrderNo,
            OrderType = 1, // Income
            PaymentMethod = 1, // Default Online? Or unknown yet.
            RegistrationMode = input.RegistrationMode,
            MerchantId = eventInfo?.MerchantId, // 设置商户ID
            EventId = input.EventId,
            RegistrationId = entity.Id,
            OriginalAmount = totalAmount,
            ActualAmount = totalAmount, // Before discount
            DiscountAmount = 0,
            OrderStatus = OrderStatus.Pending, // Pending
            CreatedTime = DateTime.Now,
            CreatedUserId = entity.CreatedUserId
        };
        await _orderRepository.InsertAsync(order);

        return entity.OrderNo;
    }

    /// <summary>
    /// 订单分页查询
    /// </summary>
    [DisplayName("订单分页查询")]
    [HttpGet("page")]
    public async Task<PageResult<OrderListOutput>> Page([FromQuery] OrderQueryInput input)
    {
        var userId = _authManager.UserId;
        // 判断是否是商户账号
        var merchant = await _merchantRepository.GetFirstAsync(m => m.CreatedUserId == userId);
        
        var query = _orderRepository.AsQueryable()
            .LeftJoin<EventInfo>((o, e) => o.EventId == e.Id)
            .LeftJoin<YD_Event.Core.Entities.Merchant>((o, e, m) => o.MerchantId == m.Id)
            .LeftJoin<EventRegistration>((o, e, m, r) => o.RegistrationId == r.Id)
            .LeftJoin<YD_Event.Core.Entities.Order>((o, e, m, r, ro) => o.RelatedOrderId == ro.Id) // Join self for Related Order No
            .WhereIF(!string.IsNullOrWhiteSpace(input.OrderNo), (o, e, m, r, ro) => o.OrderNo.Contains(input.OrderNo))
            .WhereIF(!string.IsNullOrWhiteSpace(input.EventName), (o, e, m, r, ro) => e.EventName.Contains(input.EventName))
            .WhereIF(input.OrderType.HasValue, (o, e, m, r, ro) => o.OrderType == input.OrderType)
            .WhereIF(input.OrderStatus.HasValue, (o, e, m, r, ro) => o.OrderStatus == input.OrderStatus)
            .WhereIF(input.PaymentMethod.HasValue, (o, e, m, r, ro) => o.PaymentMethod == input.PaymentMethod)
            .WhereIF(input.RegistrationMode.HasValue, (o, e, m, r, ro) => o.RegistrationMode == input.RegistrationMode)
            .WhereIF(!string.IsNullOrWhiteSpace(input.ContactPhone), (o, e, m, r, ro) => r.ContactPhone.Contains(input.ContactPhone))
            .WhereIF(input.StartTime.HasValue, (o, e, m, r, ro) => o.PaymentTime >= input.StartTime) // 支付时间筛选
            .WhereIF(input.EndTime.HasValue, (o, e, m, r, ro) => o.PaymentTime <= input.EndTime)
            .OrderByDescending((o, e, m, r, ro) => o.CreatedTime);

        if (merchant != null && !_authManager.IsSuperAdmin)
        {
            // 个人用户只能看到自己关联的订单
            query = query.Where(o => o.MerchantId == merchant.Id);
        }

        var result = await query.Select((o, e, m, r, ro) => new OrderListOutput
            {
                Id = o.Id,
                OrderNo = o.OrderNo,
                UnitName = SqlFunc.IsNullOrEmpty(m.MerchantName) ? "/" : m.MerchantName,
                EventName = e.EventName,
                OrderType = o.OrderType == 1 ? "收入" : "退款",
                RelatedOrderNo = ro.OrderNo,
                PaymentMethod = o.PaymentMethod == 1 ? "线上" : "线下",
                PaymentProofUrl = o.PaymentProofUrl,
                RegistrationMode = o.RegistrationMode == 1 ? "个人" : "团队",
                ContactName = r.ContactName,
                ContactPhone = r.ContactPhone,
                OriginalAmount = o.OriginalAmount,
                DiscountAmount = o.DiscountAmount,
                ActualAmount = o.ActualAmount,
                OrderStatus = o.OrderStatus,
                CreatedTime = o.CreatedTime,
                PaymentTime = o.PaymentTime,
                RefundAmount = o.OrderType == 2 ? o.ActualAmount : 0, // 如果是退款订单，ActualAmount即为退款金额
                RefundTime = o.OrderType == 2 ? o.PaymentTime : null  // 退款时间
            })
            .ToPagedListAsync(input);

        return result;
    }

    /// <summary>
    /// 获取订单详情
    /// </summary>
    [DisplayName("获取订单详情")]
    [HttpGet("detail")]
    public async Task<OrderDetailOutput> Detail([FromQuery] long id)
    {
        var order = await _orderRepository.AsQueryable()
            .LeftJoin<EventInfo>((o, e) => o.EventId == e.Id)
            .Where(o => o.Id == id)
            .Select((o, e) => new { Order = o, EventName = e.EventName })
            .FirstAsync();

        if (order == null) throw Oops.Bah("订单不存在");

        var registrationId = order.Order.RegistrationId;
        var items = await _itemRepository.AsQueryable().Where(x => x.RegistrationId == registrationId).ToListAsync();
        var persons = await _personRepository.AsQueryable().Where(x => x.RegistrationId == registrationId).ToListAsync();

        // Convert items and persons to Dto
        var itemDtos = items.Select(x => new OrderItemDto 
        { 
            ProjectName = x.ProjectName, // Assume stored or join
            GroupName = x.GroupName, 
            Fee = x.TotalPrice 
        }).ToList();

        var personDtos = persons.Select(x => new OrderPersonDto 
        { 
            Name = x.Name, 
            GroupName = x.GroupName 
        }).ToList();

        return new OrderDetailOutput
        {
            Id = order.Order.Id,
            OrderNo = order.Order.OrderNo,
            OrderType = order.Order.OrderType,
            OrderStatus = order.Order.OrderStatus,
            EventName = order.EventName,
            ProjectNames = string.Join(",", items.Select(x => x.ProjectName).Distinct()),
            GroupNames = string.Join(",", items.Select(x => x.GroupName).Distinct()),
            Items = itemDtos,
            Persons = personDtos,
            PaymentMethod = order.Order.PaymentMethod == 1 ? "线上" : "线下",
            PaymentProofUrl = order.Order.PaymentProofUrl,
            OriginalAmount = order.Order.OriginalAmount,
            DiscountAmount = order.Order.DiscountAmount,
            ActualAmount = order.Order.ActualAmount,
            CreatedTime = order.Order.CreatedTime
        };
    }

    /// <summary>
    /// 更新订单状态
    /// </summary>
    [DisplayName("更新订单状态")]
    [HttpPut("status")]
    public async Task UpdateStatus(UpdateOrderStatusInput input)
    {
        var order = await _orderRepository.GetByIdAsync(input.Id);
        if (order == null) throw Oops.Bah("订单不存在");

        // Update Order
        order.OrderStatus = input.PaymentStatus == 1 ? OrderStatus.Paid : OrderStatus.Pending; // Assuming 1 is paid/success
        if (input.PaymentStatus == 1)
        {
            order.PaymentTime = DateTime.Now;
        }
        await _orderRepository.UpdateAsync(order);

        // Update Registration sync
        var reg = await _registrationRepository.GetByIdAsync(order.RegistrationId);
        if (reg != null)
        {
            reg.PaymentStatus = input.PaymentStatus;
            reg.PaymentTime = order.PaymentTime;
            await _registrationRepository.UpdateAsync(reg);
        }
    }

    /// <summary>
    /// 获取建议退款金额
    /// </summary>
    [DisplayName("获取建议退款金额")]
    [HttpGet("refund-amount")]
    public async Task<decimal> GetRefundAmount([FromQuery] long orderId)
    {
        var order = await _orderRepository.GetByIdAsync(orderId);
        if (order == null) throw Oops.Bah("订单不存在");
        
        var eventInfo = await _eventRepository.GetByIdAsync(order.EventId);
        if (eventInfo == null) return order.ActualAmount;

        return await _refundConfigService.CalculateRefundAmount(order.ActualAmount, eventInfo.MatchStartTime);
    }

    /// <summary>
    /// 订单退款
    /// </summary>
    [DisplayName("订单退款")]
    [HttpPost("refund")]
    [UnitOfWork]
    public async Task Refund(RefundOrderInput input)
    {
        var order = await _orderRepository.GetByIdAsync(input.Id);
        if (order == null) throw Oops.Bah("订单不存在");

        if (order.OrderStatus != OrderStatus.Paid) throw Oops.Bah("订单未支付，无法退款");

        // 1. Create Refund Order
        var refundOrder = new YD_Event.Core.Entities.Order
        {
            Id = _idGenerator.NextId(),
            OrderNo = "REF" + DateTime.Now.ToString("yyyyMMddHHmmss"),
            OrderType = 2, // Refund
            PaymentMethod = order.PaymentMethod,
            RegistrationMode = order.RegistrationMode,
            MerchantId = order.MerchantId,
            EventId = order.EventId,
            RegistrationId = order.RegistrationId,
            RelatedOrderId = order.Id, // Link to original
            OriginalAmount = order.ActualAmount,
            ActualAmount = input.RefundAmount, // Refund Amount
            OrderStatus = OrderStatus.Refunded, // Success (Refunded)
            PaymentTime = DateTime.Now,
            Remark = input.Reason,
            CreatedTime = DateTime.Now,
            CreatedUserId = _idGenerator.NewLong() // System or current user
        };
        await _orderRepository.InsertAsync(refundOrder);

        // 2. Update Registration Status
        var reg = await _registrationRepository.GetByIdAsync(order.RegistrationId);
        if (reg != null)
        {
            reg.PaymentStatus = 3; // Refunded
            await _registrationRepository.UpdateAsync(reg);
        }
    }

    /// <summary>
    /// 删除订单
    /// </summary>
    [DisplayName("删除订单")]
    [HttpPost("delete")]
    public async Task Delete([FromBody] List<long> ids)
    {
        await _orderRepository.DeleteAsync(x => ids.Contains(x.Id));
    }
    
    /// <summary>
    /// 导出订单
    /// </summary>
    [DisplayName("导出订单")]
    [HttpGet("export")]
    public async Task<IActionResult> Export([FromQuery] OrderQueryInput input)
    {
        var list = await _orderRepository.AsQueryable()
            .LeftJoin<EventInfo>((o, e) => o.EventId == e.Id)
            .LeftJoin<YD_Event.Core.Entities.Merchant>((o, e, m) => o.MerchantId == m.Id)
            .LeftJoin<EventRegistration>((o, e, m, r) => o.RegistrationId == r.Id)
            .LeftJoin<YD_Event.Core.Entities.Order>((o, e, m, r, ro) => o.RelatedOrderId == ro.Id)
            .WhereIF(!string.IsNullOrWhiteSpace(input.OrderNo), (o, e, m, r, ro) => o.OrderNo.Contains(input.OrderNo))
            .WhereIF(!string.IsNullOrWhiteSpace(input.EventName), (o, e, m, r, ro) => e.EventName.Contains(input.EventName))
            .WhereIF(input.OrderType.HasValue, (o, e, m, r, ro) => o.OrderType == input.OrderType)
            .WhereIF(input.OrderStatus.HasValue, (o, e, m, r, ro) => o.OrderStatus == input.OrderStatus)
            .WhereIF(input.PaymentMethod.HasValue, (o, e, m, r, ro) => o.PaymentMethod == input.PaymentMethod)
            .WhereIF(input.RegistrationMode.HasValue, (o, e, m, r, ro) => o.RegistrationMode == input.RegistrationMode)
            .WhereIF(!string.IsNullOrWhiteSpace(input.ContactPhone), (o, e, m, r, ro) => r.ContactPhone.Contains(input.ContactPhone))
            .WhereIF(input.StartTime.HasValue, (o, e, m, r, ro) => o.CreatedTime >= input.StartTime)
            .WhereIF(input.EndTime.HasValue, (o, e, m, r, ro) => o.CreatedTime <= input.EndTime)
            .OrderByDescending((o, e, m, r, ro) => o.CreatedTime)
            .Select((o, e, m, r, ro) => new OrderListOutput
            {
                OrderNo = o.OrderNo,
                UnitName = SqlFunc.IsNullOrEmpty(m.MerchantName) ? "/" : m.MerchantName,
                EventName = e.EventName,
                OrderType = o.OrderType == 1 ? "收入" : "退款",
                RelatedOrderNo = ro.OrderNo,
                PaymentMethod = o.PaymentMethod == 1 ? "线上" : "线下",
                RegistrationMode = o.RegistrationMode == 1 ? "个人" : "团队",
                ContactName = r.ContactName,
                ContactPhone = r.ContactPhone,
                OriginalAmount = o.OriginalAmount,
                DiscountAmount = o.DiscountAmount,
                ActualAmount = o.ActualAmount,
                OrderStatus = o.OrderStatus,
                CreatedTime = o.CreatedTime
            })
            .ToListAsync();

        // Calculate Summary
        decimal totalOriginal = list.Sum(x => x.OriginalAmount);
        decimal totalDiscount = list.Sum(x => x.DiscountAmount);
        decimal totalRefund = list.Where(x => x.OrderType == "退款").Sum(x => x.ActualAmount);
        decimal totalActual = list.Where(x => x.OrderType == "收入").Sum(x => x.ActualAmount);

        var sb = new StringBuilder();
        // Summary Row
        sb.AppendLine($"汇总信息: 原金额:{totalOriginal}, 优惠金额:{totalDiscount}, 退款金额:{totalRefund}, 实付金额:{totalActual}");
        sb.AppendLine("订单编号,单位名称,所属赛事,订单类型,关联订单,支付方式,报名方式,报名用户,报名账号,原金额,优惠金额,实付/退款金额,订单状态,生成时间");
        
        foreach (var item in list)
        {
            sb.AppendLine($"{item.OrderNo},{item.UnitName},{item.EventName},{item.OrderType},{item.RelatedOrderNo},{item.PaymentMethod},{item.RegistrationMode},{item.ContactName},{item.ContactPhone},{item.OriginalAmount},{item.DiscountAmount},{item.ActualAmount},{item.OrderStatus},{item.CreatedTime}");
        }

        var bytes = Encoding.UTF8.GetBytes(sb.ToString());
        return new FileContentResult(bytes, "text/csv")
        {
            FileDownloadName = $"Orders_{DateTime.Now:yyyyMMddHHmmss}.csv"
        };
    }
}