ANTOOZA-BACKEND/Domain/Entities/Donations/DonorTitleSelection.cs

using System.ComponentModel.DataAnnotations;
using System.ComponentModel.DataAnnotations.Schema;
using Domain.Entities.Members;

namespace Domain.Entities.Donations;

/// <summary>
/// 후원자가 채널별로 선택한 대표 칭호 (채널당 1개).
/// </summary>
public sealed class DonorTitleSelection
{
    [ForeignKey(nameof(DonorMemberID))]
    public Member Donor { get; private set; } = null!;

    [ForeignKey(nameof(ChannelID))]
    public Channel Channel { get; private set; } = null!;

    [ForeignKey(nameof(SelectedTitleID))]
    public ChannelTitle? SelectedTitle { get; private set; }

    [Key]
    public int ID { get; private set; }

    public int DonorMemberID { get; private set; }

    public int ChannelID { get; private set; }

    public int? SelectedTitleID { get; private set; }

    public DateTime? UpdatedAt { get; private set; }

    public DateTime CreatedAt { get; private set; } = DateTime.UtcNow;

    private DonorTitleSelection() { }

    private DonorTitleSelection(int donorMemberID, int channelID, int? selectedTitleID)
    {
        if (donorMemberID <= 0)
        {
            throw new ArgumentOutOfRangeException(nameof(donorMemberID));
        }

        if (channelID <= 0)
        {
            throw new ArgumentOutOfRangeException(nameof(channelID));
        }

        DonorMemberID = donorMemberID;
        ChannelID = channelID;
        SelectedTitleID = selectedTitleID;
    }

    public static DonorTitleSelection Create(int donorMemberID, int channelID, int? selectedTitleID)
    {
        return new(donorMemberID, channelID, selectedTitleID);
    }

    public void Update(int? selectedTitleID)
    {
        SelectedTitleID = selectedTitleID;
        UpdatedAt = DateTime.UtcNow;
    }
}