using MediatR;
using BuildFlow.Application.Roles.DTOs;
using BuildFlow.Infrastructure.Persistence;
using BuildFlow.Application.Roles.Queries;

namespace BuildFlow.Application.Roles.Handlers;

/// <summary>
/// Get角色List查询处理器。执行业务校验后持久化。
/// </summary>
public class GetRoleListQueryHandler(RagDbContext db) : IRequestHandler<GetRoleListQuery, List<RoleDto>>
{
    public async Task<List<RoleDto>> Handle(GetRoleListQuery request, CancellationToken ct)
    {
        return await db.Roles
            .Include(r => r.RolePermissions).ThenInclude(rp => rp.Permission)
            .Select(r => new RoleDto(
                r.Id, r.Name, r.Description, r.CreatedAt,
                r.RolePermissions.Select(rp => rp.Permission.Code).ToList()))
            .ToListAsync(ct);
    }
}