using YD_Event.Application.Client.Dtos;
using YD_Event.Application.Event;

namespace YD_Event.Application.Client;

/// <summary>从秩序册实时生成检录项目、组别和列对象。</summary>
public class CheckinScheduleService : ITransient
{
    private readonly ISqlSugarRepository<EventInfo> _eventRepository;
    private readonly ISqlSugarRepository<EventRegistrationPerson> _personRepository;
    private readonly EventArrangementService _arrangementService;

    public CheckinScheduleService(
        ISqlSugarRepository<EventInfo> eventRepository,
        ISqlSugarRepository<EventRegistrationPerson> personRepository,
        EventArrangementService arrangementService)
    {
        _eventRepository = eventRepository;
        _personRepository = personRepository;
        _arrangementService = arrangementService;
    }

    public async Task<CheckinEventOptionsDto> GetOptionsAsync(long eventId)
    {
        var evt = await _eventRepository.GetFirstAsync(x =>
            x.Id == eventId && !x.DeleteMark && x.Status == AvailabilityStatus.Enable);
        if (evt == null) throw Oops.Bah("赛事不存在或已停用");

        // Preview 的每一行就是秩序册中的一列：个人项目一人，团队项目可以多人。
        var rows = await _arrangementService.Preview(eventId);
        if (rows.Count == 0) throw Oops.Bah("当前赛事尚未生成有效秩序册，不能创建检录任务");

        var personIds = rows.SelectMany(x => x.RegistrationPersonIds).Distinct().ToList();
        var persons = personIds.Count == 0
            ? new List<EventRegistrationPerson>()
            : await _personRepository.AsQueryable()
                .Where(x => personIds.Contains(x.Id) && !x.DeleteMark && x.PersonType == PersonType.Athlete)
                .ToListAsync();
        var personMap = persons.ToDictionary(x => x.Id);

        // 团队项目沿用报名项目作为检录单位；个人项目追加报名人员 ID，
        // 避免单位账号在同一报名项目下填报多人时共用同一个检录键。
        var units = rows.Select((row, index) => new CheckinOrderBookUnitDto
        {
            UnitKey = BuildUnitKey(row.EventProjectId, row.RegistrationItemId,
                row.IsTeamProject ? null : row.RegistrationPersonIds.SingleOrDefault()),
            IsTeamProject = row.IsTeamProject,
            Order = index + 1,
            SessionIndex = row.SessionIndex,
            VenueIndex = row.VenueIndex,
            VenueName = $"{row.VenueIndex}号场地",
            EventProjectId = row.EventProjectId,
            ProjectId = row.ProjectId,
            ProjectName = row.ProjectName,
            GroupId = row.EventProjectGroupId,
            GroupName = row.GroupName,
            RegistrationItemId = row.RegistrationItemId,
            TeamName = row.TeamName ?? string.Empty,
            UnitName = row.UnitName ?? string.Empty,
            RegistrationPersonIds = row.RegistrationPersonIds.Distinct().ToList(),
            Athletes = row.RegistrationPersonIds.Distinct()
                .Where(personMap.ContainsKey)
                .Select(personId =>
                {
                    var person = personMap[personId];
                    return new CheckinAthleteDto
                    {
                        Id = person.Id,
                        UserId = person.UserId,
                        BibNo = FormatBibNo(person.Id),
                        Name = person.Name,
                        TeamName = row.TeamName ?? string.Empty
                    };
                }).ToList()
        }).ToList();

        var projects = units.GroupBy(x => new { x.EventProjectId, x.ProjectId, x.ProjectName })
            .Select((project, projectIndex) => new CheckinProjectOptionDto
            {
                EventProjectId = project.Key.EventProjectId,
                ProjectId = project.Key.ProjectId,
                ProjectName = project.Key.ProjectName,
                Order = projectIndex + 1,
                Groups = project.Where(x => x.GroupId.HasValue)
                    .GroupBy(x => new { Id = x.GroupId!.Value, x.GroupName })
                    .Select((group, groupIndex) => new CheckinGroupOptionDto
                    {
                        Id = group.Key.Id,
                        EventProjectId = project.Key.EventProjectId,
                        ProjectId = project.Key.ProjectId,
                        ProjectName = project.Key.ProjectName,
                        GroupName = group.Key.GroupName,
                        Order = groupIndex + 1
                    }).ToList()
            }).ToList();

        return new CheckinEventOptionsDto
        {
            EventId = evt.Id,
            EventName = evt.EventName,
            Projects = projects,
            Units = units,
            // 兼容旧调用方：Sessions 不再是检录对象。
            Sessions = new List<CheckinSessionOptionDto>(),
            Rounds = new List<CheckinRoundOptionDto>()
        };
    }

    public static CheckinOrderBookUnitDto ResolveUnit(CheckinEventOptionsDto options, string unitKey)
    {
        var unit = options.Units.FirstOrDefault(x => x.UnitKey == unitKey);
        return unit ?? throw Oops.Bah("所选检录对象不属于当前赛事秩序册");
    }

    /// <summary>
    /// 生成检录对象唯一键。团队项目不传人员 ID，个人项目必须传入人员 ID。
    /// </summary>
    public static string BuildUnitKey(
        long eventProjectId, long registrationItemId, long? registrationPersonId = null)
    {
        var key = $"EP{eventProjectId}-RI{registrationItemId}";
        return registrationPersonId.HasValue && registrationPersonId.Value > 0
            ? $"{key}-RP{registrationPersonId.Value}"
            : key;
    }

    private static string FormatBibNo(long personId)
    {
        var value = personId.ToString();
        return value.Length > 6 ? value[^6..] : value.PadLeft(6, '0');
    }
}