ANTOOZA-BACKEND/Application/Features/Api/MyPage/ChangeBanner/Handler.cs

using Application.Abstractions.Data;
using Application.Abstractions.Messaging;
using Microsoft.EntityFrameworkCore;
using SharedKernel.Results;
using SharedKernel.Storage;

namespace Application.Features.Api.MyPage.ChangeBanner;

internal sealed class Handler(IAppDbContext db, IFileStorage fileStorage) : ICommandHandler<Command, Result<string?>>
{
    public async Task<Result<string?>> Handle(Command request, CancellationToken ct)
    {
        var member = await db.Member.FirstOrDefaultAsync(m => m.ID == request.MemberID, ct);
        if (member is null)
        {
            return Result.Failure<string?>(Error.NotFound("MyPage.MemberNotFound", "회원 정보를 찾을 수 없습니다."));
        }

        if (!string.IsNullOrEmpty(member.BannerUrl))
        {
            fileStorage.DeleteByUrl(member.BannerUrl);
        }

        string? bannerUrl = null;

        if (request.Banner is not null && request.Banner.Length > 0)
        {
            FileStoragePath uploadPath = new(UploadTarget.Upload, UploadFolder.MemberBanner, request.MemberID);
            string[] allowedExtensions = [".jpg", ".jpeg", ".png", ".gif", ".webp"];

            var result = await fileStorage.SaveFileAsync(request.Banner, uploadPath, allowedExtensions, ct);
            bannerUrl = result?.Url;
        }

        member.SetBannerUrl(bannerUrl);
        await db.SaveChangesAsync(ct);

        return Result.Success<string?>(bannerUrl);
    }
}