using SPMS.Application.DTOs.Notice;
using SPMS.Application.Interfaces;
using SPMS.Domain.Common;
using SPMS.Domain.Exceptions;
using SPMS.Domain.Interfaces;

namespace SPMS.Application.Services;

public class NoticeService : INoticeService
{
    private readonly INoticeRepository _noticeRepository;

    public NoticeService(INoticeRepository noticeRepository)
    {
        _noticeRepository = noticeRepository;
    }

    public async Task<NoticeListResponseDto> GetListAsync(NoticeListRequestDto request)
    {
        var (items, totalCount) = await _noticeRepository.GetActivePagedAsync(request.Page, request.Size);

        var totalPages = (int)Math.Ceiling((double)totalCount / request.Size);

        return new NoticeListResponseDto
        {
            Items = items.Select(n => new NoticeSummaryDto
            {
                NoticeId = n.Id,
                Title = n.Title,
                IsImportant = n.IsPinned,
                CreatedAt = n.CreatedAt
            }).ToList(),
            Pagination = new PaginationDto
            {
                Page = request.Page,
                Size = request.Size,
                TotalCount = totalCount,
                TotalPages = totalPages
            }
        };
    }

    public async Task<NoticeInfoResponseDto> GetInfoAsync(NoticeInfoRequestDto request)
    {
        var notice = await _noticeRepository.GetActiveByIdAsync(request.NoticeId);
        if (notice == null)
            throw new SpmsException(ErrorCodes.NotFound, "존재하지 않는 공지사항입니다.", 404);

        return new NoticeInfoResponseDto
        {
            NoticeId = notice.Id,
            Title = notice.Title,
            Content = notice.Content,
            IsImportant = notice.IsPinned,
            CreatedAt = notice.CreatedAt
        };
    }
}