using Application.Abstractions.Messaging; using Application.Abstractions.Data; using Microsoft.EntityFrameworkCore; namespace Application.Features.Admin.Crypto.Board.LinkBoard { public sealed class Handler(IAppDbContext db) : ICommandHandler { public async Task Handle(Command request, CancellationToken ct) { if (!await db.Coin.AnyAsync(c => c.ID == request.CoinID, ct)) { throw new KeyNotFoundException("코인을 찾을 수 없습니다."); } var board = await db.Board.FirstOrDefaultAsync(b => b.ID == request.BoardID, ct); if (board is null) { throw new KeyNotFoundException("게시판을 찾을 수 없습니다."); } if (board.CoinID is not null) { throw new InvalidOperationException("이미 다른 코인에 연결된 게시판입니다."); } board.CoinID = request.CoinID; await db.SaveChangesAsync(ct); } } }