using YD_Event.Application.Event.Dtos;
using YD_Event.Core.Entities;
using YD_Event.Core.Enum;
using AppUserEntity = YD_Event.Core.Entities.AppUser;
using SysUserEntity = YD_Event.Core.Entities.SysUser;
using MerchantEntity = YD_Event.Core.Entities.Merchant;

namespace YD_Event.Application.Event;

/// <summary>
/// 参赛记录管理
/// </summary>
public class EventRecordService : BaseService<EventRegistration>, ITransient
{
    private readonly ISqlSugarRepository<EventRegistration> _registrationRep;
    private readonly ISqlSugarRepository<EventInfo> _eventRep;
    private readonly ISqlSugarRepository<EventCertificate> _certificateRep;
    private readonly ISqlSugarRepository<AppUserEntity> _appUserRep;
    private readonly ISqlSugarRepository<SysUserEntity> _sysUserRep;
    private readonly ISqlSugarRepository<MerchantEntity> _merchantRep;
    private readonly ISqlSugarRepository<EventRegistrationItem> _registrationItemRep;
    private readonly ISqlSugarRepository<EventResult> _resultRep;

    public EventRecordService(ISqlSugarRepository<EventRegistration> registrationRep,
        ISqlSugarRepository<EventInfo> eventRep,
        ISqlSugarRepository<EventCertificate> certificateRep,
        ISqlSugarRepository<AppUserEntity> appUserRep,
        ISqlSugarRepository<SysUserEntity> sysUserRep,
        ISqlSugarRepository<MerchantEntity> merchantRep,
        ISqlSugarRepository<EventRegistrationItem> registrationItemRep,
        ISqlSugarRepository<EventResult> resultRep) : base(registrationRep)
    {
        _registrationRep = registrationRep;
        _eventRep = eventRep;
        _certificateRep = certificateRep;
        _appUserRep = appUserRep;
        _sysUserRep = sysUserRep;
        _merchantRep = merchantRep;
        _registrationItemRep = registrationItemRep;
        _resultRep = resultRep;
    }

    /// <summary>
    /// 分页查询参赛记录
    /// </summary>
    [HttpGet("page")]
    public async Task<PageResult<EventRecordOutput>> Page([FromQuery] EventRecordPageInput input)
    {
        // 参数验证
        ValidateInput(input);

        // 第一步：查询用户报名过的所有赛事（去重，按赛事分组）
        var eventsQuery = _registrationRep.AsQueryable()
            .LeftJoin<EventInfo>((r, e) => r.EventId == e.Id)
            .LeftJoin<AppUserEntity>((r, e, u) => r.CreatedUserId == u.Id)
            .LeftJoin<SysUserEntity>((r, e, u, s) => r.CreatedUserId == s.Id)
            .LeftJoin<MerchantEntity>((r, e, u, s, m) => r.CreatedUserId == m.CreatedUserId)
            .WhereIF(!string.IsNullOrWhiteSpace(input.EventName), (r, e, u, s, m) => e.EventName.Contains(input.EventName))
            .WhereIF(input.StartTime.HasValue, (r, e, u, s, m) => e.MatchStartTime >= input.StartTime)
            .WhereIF(input.EndTime.HasValue, (r, e, u, s, m) => e.MatchStartTime <= input.EndTime)
            .WhereIF(input.PaymentStatus.HasValue, (r, e, u, s, m) => r.PaymentStatus == input.PaymentStatus)
            // Filter by User ID (AppUser, SysUser, or Merchant)
            .WhereIF(input.AppUserId.HasValue, (r, e, u, s, m) => u.Id == input.AppUserId)
            .WhereIF(input.SysUserId.HasValue, (r, e, u, s, m) => s.Id == input.SysUserId)
            .WhereIF(input.MerchantId.HasValue, (r, e, u, s, m) => m.CreatedUserId == input.MerchantId)
            .OrderByDescending((r, e, u, s, m) => r.CreatedTime)
            .Select((r, e, u, s, m) => new 
            {
                RegistrationId = r.Id,
                EventId = e.Id,
                EventName = e.EventName,
                EventType = e.EventType.ToString(), 
                StartTime = e.MatchStartTime,
                EndTime = e.MatchEndTime,
                PaymentStatus = r.PaymentStatus,
                ContactName = r.ContactName,
                ContactPhone = r.ContactPhone,
                TeamName = r.TeamName,
                CreatedTime = r.CreatedTime
            });

        var allEventRecords = await eventsQuery.ToListAsync();

        // 第二步：按赛事分组并聚合
        var groupedEvents = allEventRecords
            .GroupBy(x => x.EventId)
            .Select(g => {
                // 获取该赛事最早的报名记录作为主记录
                var firstRecord = g.OrderBy(x => x.CreatedTime).First();
                // 收集该赛事的所有报名记录ID
                var registrationIds = g.Select(x => x.RegistrationId).ToList();
                
                return new EventRecordOutput
                {
                    // 用赛事ID作为主要ID（避免分页问题）
                    Id = firstRecord.EventId,
                    EventName = firstRecord.EventName,
                    EventType = firstRecord.EventType,
                    StartTime = firstRecord.StartTime,
                    EndTime = firstRecord.EndTime,
                    PaymentStatus = firstRecord.PaymentStatus,
                    EventId = firstRecord.EventId,
                    ContactName = firstRecord.ContactName,
                    ContactPhone = firstRecord.ContactPhone,
                    TeamName = firstRecord.TeamName,
                    RegistrationIds = registrationIds // 保存所有报名ID用于查询证书
                };
            })
            .OrderByDescending(x => x.StartTime)
            .ToList();

        // 第三步：手动分页
        var pageIndex = input.PageNo;
        var pageSize = input.PageSize;
        var total = groupedEvents.Count;
        var pages = (int)Math.Ceiling((double)total / pageSize);
        var pagedEvents = groupedEvents
            .Skip((pageIndex - 1) * pageSize)
            .Take(pageSize)
            .ToList();

        // 第四步：获取所有需要的报名记录ID（包括所有页面的，避免数据不完整）
        var allRegistrationIds = groupedEvents.SelectMany(x => x.RegistrationIds).Distinct().ToList();

        // 第五步：获取所有报名项目
        var items = await _registrationItemRep.AsQueryable()
            .Where(i => allRegistrationIds.Contains(i.RegistrationId))
            .ToListAsync();

        // 第六步：获取所有成绩
        var results = await _resultRep.AsQueryable()
            .Where(r => allRegistrationIds.Contains(r.RegistrationId))
            .ToListAsync();

        // 第七步：将项目和成绩数据填充到结果中
        foreach (var row in pagedEvents)
        {
            // 获取该赛事所有报名记录的项目
            var registrationItems = items.Where(i => row.RegistrationIds.Contains(i.RegistrationId)).ToList();
            foreach (var item in registrationItems)
            {
                // 查找对应的成绩
                var result = results.FirstOrDefault(r => 
                    r.RegistrationId == item.RegistrationId && 
                    r.ProjectId == item.ProjectId && 
                    r.GroupName == item.GroupName);

                row.Items.Add(new EventRegistrationItemOutput
                {
                    Id = item.Id,
                    ProjectName = item.ProjectName,
                    ProjectTypeName = item.ProjectTypeName,
                    GroupName = item.GroupName,
                    PersonCount = item.PersonCount,
                    Score = result?.Score,
                    Rank = result?.Rank > 0 ? GetRankName(result.Rank) : null
                });
            }
        }

        // 第八步：构造分页结果
        var pageResult = new PageResult<EventRecordOutput>
        {
            Total = total,
            PageNo = pageIndex,
            PageSize = pageSize,
            Pages = pages,
            Rows = pagedEvents
        };

        return pageResult;
    }

    private string GetRankName(int rank)
    {
        return rank switch
        {
            1 => "冠军",
            2 => "亚军",
            3 => "季军",
            _ => $"{rank}名"
        };
    }

    /// <summary>
    /// 验证输入参数
    /// </summary>
    private void ValidateInput(EventRecordPageInput input)
    {
        // 检查是否同时提供了多个用户ID类型
        var userTypeCount = 0;
        if (input.AppUserId.HasValue) userTypeCount++;
        if (input.SysUserId.HasValue) userTypeCount++;
        if (input.MerchantId.HasValue) userTypeCount++;

        if (userTypeCount > 1)
        {
            throw Oops.Bah("只能提供一种用户类型ID参数（AppUserId、SysUserId或MerchantId）");
        }

        // 验证用户ID有效性
        if (input.AppUserId.HasValue && input.AppUserId.Value <= 0)
        {
            throw Oops.Bah("普通用户ID无效");
        }

        if (input.SysUserId.HasValue && input.SysUserId.Value <= 0)
        {
            throw Oops.Bah("系统用户ID无效");
        }

        if (input.MerchantId.HasValue && input.MerchantId.Value <= 0)
        {
            throw Oops.Bah("商户ID无效");
        }
    }

    /// <summary>
    /// 获取证书列表
    /// </summary>
    [HttpGet("certificates")]
    public async Task<List<CertificateOutput>> GetCertificates([FromQuery] List<long> registrationIds)
    {
        var certs = await _certificateRep.AsQueryable()
            .Where(c => registrationIds.Contains(c.RegistrationId))
            .ToListAsync();

        return certs.Select(c => new CertificateOutput
        {
            Id = c.Id,
            Name = c.ParticipantName,
            AwardLevel = GetAwardLevelName(c.AwardLevel),
            CertificateType = GetCertificateTypeName(c.CertificateType),
            ImageUrl = c.CertificateUrl
        }).ToList();
    }

    private string GetAwardLevelName(int level)
    {
        return level switch
        {
            1 => "特等奖",
            2 => "一等奖",
            3 => "二等奖",
            4 => "三等奖",
            5 => "优秀奖",
            _ => "未知"
        };
    }

    private string GetCertificateTypeName(int type)
    {
        return type switch
        {
            1 => "冠军证书",
            2 => "亚军证书",
            3 => "季军证书",
            4 => "优胜证书",
            5 => "参与证书",
            _ => "未知"
        };
    }
}