dpot-backend/Application/Features/Api/Crew/SearchMember/Handler.cs

using Application.Abstractions.Data;
using Application.Abstractions.Messaging;
using Microsoft.EntityFrameworkCore;

namespace Application.Features.Api.Crew.SearchMember;

internal sealed class Handler(IAppDbContext db) : IQueryHandler<Query, Response>
{
    public async Task<Response> Handle(Query request, CancellationToken ct)
    {
        if (string.IsNullOrWhiteSpace(request.Keyword) || request.Keyword.Trim().Length < 2)
        {
            return new Response([]);
        }

        var kw = request.Keyword.Trim();

        // 이미 등록된 크루원의 MemberID 목록
        var existingMemberIDs = await db.CrewMember.AsNoTracking()
            .Where(m => m.CrewID == request.CrewID)
            .Select(m => m.MemberID)
            .ToListAsync(ct);

        var list = await db.Member.AsNoTracking()
            .Where(m => !m.IsWithdraw && !m.IsDenied)
            .Where(m => !existingMemberIDs.Contains(m.ID))
            .Where(m => (m.Name != null && m.Name.Contains(kw)) || m.Email.Contains(kw))
            .Take(20)
            .Select(m => new SearchResultItem(
                m.ID,
                m.Name,
                m.Email,
                m.Thumb,
                db.Channel.AsNoTracking()
                    .Where(c => c.MemberID == m.ID)
                    .Select(c => c.Name)
                    .FirstOrDefault()
            ))
            .ToListAsync(ct);

        return new Response(list);
    }
}