using YD_Event.Application.Project.Dtos;
using YD_Event.Core.Entities;
using YD_Event.Core.Enum;
using Mapster;
using SqlSugar;
using Microsoft.Extensions.Logging;
using Easy.Core;

namespace YD_Event.Application.Project;

/// <summary>
/// 项目管理
/// </summary>
public class ProjectService : BaseService<YD_Event.Core.Entities.Project>, ITransient
{
    private readonly ISqlSugarRepository<YD_Event.Core.Entities.Project> _repository;
    private readonly ISqlSugarRepository<ProjectGroup> _groupRepository;
    private readonly ISqlSugarRepository<EventProject> _eventProjectRepository;
    private readonly ISqlSugarRepository<EventParticipationRecord> _participationRecordRepository;
    private readonly IIdGenerator _idGenerator;
    private readonly ILogger<ProjectService> _logger;

    public ProjectService(
        ISqlSugarRepository<YD_Event.Core.Entities.Project> repository,
        ISqlSugarRepository<ProjectGroup> groupRepository,
        ISqlSugarRepository<EventProject> eventProjectRepository,
        ISqlSugarRepository<EventParticipationRecord> participationRecordRepository,
        IIdGenerator idGenerator,
        ILogger<ProjectService> logger) : base(repository)
    {
        _repository = repository;
        _groupRepository = groupRepository;
        _eventProjectRepository = eventProjectRepository;
        _participationRecordRepository = participationRecordRepository;
        _idGenerator = idGenerator;
        _logger = logger;
    }

    /// <summary>
    /// 项目分页查询
    /// </summary>
    [DisplayName("项目分页查询")]
    public async Task<PageResult<ProjectDto>> Page(ProjectQueryInput input)
    {
        var query = _repository.AsQueryable()
            .WhereIF(!string.IsNullOrWhiteSpace(input.ProjectName), p => p.Name.Contains(input.ProjectName))
            .WhereIF(input.ProjectType.HasValue, p => p.ProjectType == (ProjectTypeEnum)input.ProjectType.Value)
            .OrderByDescending(p => p.Id);

        var list = await query.Select(p => new ProjectDto
        {
            Id = p.Id,
            Name = p.Name,
            ProjectType = (long)p.ProjectType,
            CompletionCountType = p.CompletionCountType,
            CompletionCount = p.CompletionCount,
            CompletionCountMin = p.CompletionCountMin,
            CompletionCountMax = p.CompletionCountMax,
            Fee = p.Fee,
            DurationMinutes = p.DurationMinutes,
            DurationSeconds = p.DurationSeconds,
            VenueCount = p.VenueCount,
            SortIndex = p.SortIndex,
            Status = p.Status,
            DeleteMark = p.DeleteMark,
            CreatedUserId = p.CreatedUserId,
            CreatedTime = p.CreatedTime,
            UpdatedUserId = p.UpdatedUserId,
            UpdatedTime = p.UpdatedTime
        })
        .ToPagedListAsync(input);

        foreach (var item in list.Rows)
        {
            item.ProjectTypeName = ((ProjectTypeEnum)item.ProjectType).Description();
            // 生成完成人数显示文本
            if (item.CompletionCountType == 0)
            {
                item.CompletionCountDisplay = item.CompletionCount.HasValue ? $"{item.CompletionCount.Value}人" : "0人";
            }
            else
            {
                var min = item.CompletionCountMin ?? 0;
                var max = item.CompletionCountMax ?? 0;
                item.CompletionCountDisplay = $"{min}-{max}人";
            }
        }

        return list;
    }

    /// <summary>
    /// 添加项目
    /// </summary>
    [DisplayName("添加项目")]
    [UnitOfWork]
    public async Task Add(AddProjectInput input)
    {
        // 验证完成人数字段
        if (input.CompletionCountType == 0)
        {
            // 单一值模式
            if (!input.CompletionCount.HasValue || input.CompletionCount.Value < 0)
            {
                throw Oops.Bah("请填写有效的完成人数");
            }
        }
        else
        {
            // 范围值模式
            if (!input.CompletionCountMin.HasValue || !input.CompletionCountMax.HasValue)
            {
                throw Oops.Bah("请填写完成人数最小值和最大值");
            }
            if (input.CompletionCountMin.Value < 0 || input.CompletionCountMax.Value < 0)
            {
                throw Oops.Bah("完成人数不能为负数");
            }
            if (input.CompletionCountMin.Value > input.CompletionCountMax.Value)
            {
                throw Oops.Bah("完成人数最小值不能大于最大值");
            }
        }

        var entity = input.Adapt<YD_Event.Core.Entities.Project>();
        entity.Id = _idGenerator.NewLong();
        entity.CreatedTime = DateTime.Now;
        entity.Status = Core.Enum.AvailabilityStatus.Enable;

        await _repository.InsertAsync(entity);

        if (input.Groups != null && input.Groups.Any())
        {
            var groups = input.Groups.Select(g => 
            {
                var group = g.Adapt<ProjectGroup>();
                group.Id = _idGenerator.NewLong();
                group.ProjectId = entity.Id;
                return group;
            }).ToList();
            await _groupRepository.InsertRangeAsync(groups);
        }
    }

    /// <summary>
    /// 更新项目
    /// </summary>
    [DisplayName("更新项目")]
    [UnitOfWork]
    public async Task Update(UpdateProjectInput input)
    {
        var entity = await _repository.GetByIdAsync(input.Id);
        if (entity == null) throw new InvalidOperationException("项目不存在");

        // 验证完成人数字段
        if (input.CompletionCountType == 0)
        {
            // 单一值模式
            if (!input.CompletionCount.HasValue || input.CompletionCount.Value < 0)
            {
                throw Oops.Bah("请填写有效的完成人数");
            }
        }
        else
        {
            // 范围值模式
            if (!input.CompletionCountMin.HasValue || !input.CompletionCountMax.HasValue)
            {
                throw Oops.Bah("请填写完成人数最小值和最大值");
            }
            if (input.CompletionCountMin.Value < 0 || input.CompletionCountMax.Value < 0)
            {
                throw Oops.Bah("完成人数不能为负数");
            }
            if (input.CompletionCountMin.Value > input.CompletionCountMax.Value)
            {
                throw Oops.Bah("完成人数最小值不能大于最大值");
            }
        }

        input.Adapt(entity);
        entity.UpdatedTime = DateTime.Now;
        await _repository.UpdateAsync(entity);

        await _groupRepository.SoftDeleteAsync(x => x.ProjectId == entity.Id);

        if (input.Groups != null && input.Groups.Any())
        {
            var groups = input.Groups.Select(g => 
            {
                var group = g.Adapt<ProjectGroup>();
                group.Id = _idGenerator.NewLong();
                group.ProjectId = entity.Id;
                return group;
            }).ToList();
            await _groupRepository.InsertRangeAsync(groups);
        }
    }

    /// <summary>
    /// 删除项目
    /// </summary>
    [DisplayName("删除项目")]
    [UnitOfWork]
    public async Task Delete(List<long> ids)
    {
        _logger.LogInformation("开始删除项目：项目ID列表={Ids}", string.Join(",", ids));

        // 检查项目是否被赛事使用
        var hasEventProjects = await _eventProjectRepository.IsAnyAsync(x => ids.Contains(x.ProjectId));
        if (hasEventProjects)
        {
            _logger.LogWarning("删除失败：部分项目正在被赛事使用");
            throw new InvalidOperationException("部分项目正在被赛事使用，无法删除。请先从赛事中移除这些项目。");
        }

        // 检查是否有报名数据关联
        var eventProjectIds = await _eventProjectRepository.AsQueryable()
            .Where(x => ids.Contains(x.ProjectId))
            .Select(x => x.Id)
            .ToListAsync();
        
        if (eventProjectIds.Any())
        {
            var hasParticipations = await _participationRecordRepository.IsAnyAsync(x => 
                eventProjectIds.Contains(x.ProjectId) && !x.DeleteMark);
            
            if (hasParticipations)
            {
                _logger.LogWarning("删除失败：部分项目已有报名数据");
                throw new InvalidOperationException("部分项目已有报名数据，为保证数据完整性，无法删除。");
            }
        }

        // 执行删除 - 软删
        await _repository.SoftDeleteByIdsAsync(ids);
        await _groupRepository.SoftDeleteAsync(x => ids.Contains(x.ProjectId));

        _logger.LogInformation("删除项目成功：项目ID列表={Ids}", string.Join(",", ids));
    }

    /// <summary>
    /// 获取项目详情
    /// </summary>
    [DisplayName("获取项目详情")]
    public async Task<ProjectDto> Detail(long id)
    {
        var p = await _repository.GetByIdAsync(id);
        if (p == null) throw new InvalidOperationException("项目不存在");
        
        var dto = p.Adapt<ProjectDto>();
        dto.ProjectType = (long)p.ProjectType;
        dto.ProjectTypeName = p.ProjectType.Description();

        // 生成完成人数显示文本
        if (dto.CompletionCountType == 0)
        {
            dto.CompletionCountDisplay = dto.CompletionCount.HasValue ? $"{dto.CompletionCount.Value}人" : "0人";
        }
        else
        {
            var min = dto.CompletionCountMin ?? 0;
            var max = dto.CompletionCountMax ?? 0;
            dto.CompletionCountDisplay = $"{min}-{max}人";
        }

        var groups = await _groupRepository.GetListAsync(x => x.ProjectId == id);
        dto.Groups = groups.Adapt<List<ProjectGroupDto>>();
        
        return dto;
    }

    /// <summary>
    /// 项目统计类型
    /// </summary>
    public enum ProjectStatisticType
    {
        /// <summary>
        /// 参赛人数
        /// </summary>
        ParticipationCount = 1,

        /// <summary>
        /// 完成人数
        /// </summary>
        CompletionCount = 2
    }

    /// <summary>
    /// 获取项目统计数据（单个项目）
    /// </summary>
    /// <param name="projectId">项目ID</param>
    /// <param name="statisticType">统计类型</param>
    /// <returns>统计数值</returns>
    [DisplayName("获取项目统计数据")]
    public async Task<int> GetProjectStatisticAsync(long projectId, ProjectStatisticType statisticType)
    {
        if (projectId <= 0)
        {
            _logger.LogWarning("Invalid projectId: {ProjectId}", projectId);
            return 0;
        }

        var eventProjectIds = await _eventProjectRepository.AsQueryable()
            .Where(ep => ep.ProjectId == projectId)
            .Select(ep => ep.Id)
            .ToListAsync();

        if (!eventProjectIds.Any())
        {
            return 0;
        }

        var query = _participationRecordRepository.AsQueryable()
            .Where(pr => eventProjectIds.Contains(pr.ProjectId) && !pr.DeleteMark);

        switch (statisticType)
        {
            case ProjectStatisticType.ParticipationCount:
                query = query.Where(pr => pr.ParticipationStatus == ParticipationStatus.Participated || pr.ParticipationStatus == ParticipationStatus.Completed);
                break;

            case ProjectStatisticType.CompletionCount:
                query = query.Where(pr => pr.ParticipationStatus == ParticipationStatus.Completed);
                break;

            default:
                _logger.LogWarning("Unknown statistic type: {StatisticType}", statisticType);
                return 0;
        }

        var count = await query.CountAsync();
        return count;
    }

    /// <summary>
    /// 批量获取项目统计数据（性能优化，避免N+1查询）
    /// </summary>
    /// <param name="projectIds">项目ID列表</param>
    /// <param name="statisticType">统计类型</param>
    /// <returns>字典，Key为项目ID，Value为统计数值</returns>
    [DisplayName("批量获取项目统计数据")]
    public async Task<Dictionary<long, int>> GetProjectStatisticsBatchAsync(List<long> projectIds, ProjectStatisticType statisticType)
    {
        var result = new Dictionary<long, int>();

        if (projectIds == null || !projectIds.Any())
        {
            return result;
        }

        foreach (var projectId in projectIds)
        {
            result[projectId] = 0;
        }

        var eventProjects = await _eventProjectRepository.AsQueryable()
            .Where(ep => projectIds.Contains(ep.ProjectId))
            .Select(ep => new { ep.Id, ep.ProjectId })
            .ToListAsync();

        if (!eventProjects.Any())
        {
            return result;
        }

        var eventProjectIds = eventProjects.Select(ep => ep.Id).ToList();

        var query = _participationRecordRepository.AsQueryable()
            .Where(pr => eventProjectIds.Contains(pr.ProjectId) && !pr.DeleteMark);

        switch (statisticType)
        {
            case ProjectStatisticType.ParticipationCount:
                query = query.Where(pr => pr.ParticipationStatus == ParticipationStatus.Participated || pr.ParticipationStatus == ParticipationStatus.Completed);
                break;

            case ProjectStatisticType.CompletionCount:
                query = query.Where(pr => pr.ParticipationStatus == ParticipationStatus.Completed);
                break;

            default:
                _logger.LogWarning("Unknown statistic type: {StatisticType}", statisticType);
                return result;
        }

        var records = await query.ToListAsync();

        foreach (var record in records)
        {
            var projectId = eventProjects.FirstOrDefault(ep => ep.Id == record.ProjectId)?.ProjectId;
            if (projectId.HasValue && result.ContainsKey(projectId.Value))
            {
                result[projectId.Value]++;
            }
        }

        return result;
    }
}