using System.ComponentModel.DataAnnotations;

namespace Domain.Entities.Chat;

/// <summary>
/// 채팅 제재 (개미투자 D2) — RoomKey NULL 은 전체 룸 제재, ExpiresAt NULL 은 무기한.
/// 발언(SendMessage)만 차단하고 읽기는 허용한다.
/// </summary>
public class ChatBan
{
    [Key]
    public int ID { get; private set; }

    /// <summary>제재 대상 회원 (FK Member)</summary>
    public int MemberID { get; private set; }

    /// <summary>제재 룸 키 — NULL 이면 전체 룸</summary>
    public string? RoomKey { get; private set; }

    /// <summary>제재 사유</summary>
    public string Reason { get; private set; } = default!;

    /// <summary>만료 일시 (UTC) — NULL 이면 무기한</summary>
    public DateTime? ExpiresAt { get; private set; }

    /// <summary>제재 등록자 (Admin 계정 표시명)</summary>
    public string CreatedBy { get; private set; } = default!;

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

    private ChatBan() { }

    public static ChatBan Create(int memberID, string? roomKey, string reason, DateTime? expiresAt, string createdBy)
    {
        if (memberID <= 0)
        {
            throw new ArgumentOutOfRangeException(nameof(memberID));
        }

        if (string.IsNullOrWhiteSpace(reason))
        {
            throw new ArgumentException("reason required", nameof(reason));
        }

        if (string.IsNullOrWhiteSpace(createdBy))
        {
            throw new ArgumentException("createdBy required", nameof(createdBy));
        }

        return new ChatBan
        {
            MemberID = memberID,
            RoomKey = string.IsNullOrWhiteSpace(roomKey) ? null : roomKey.Trim(),
            Reason = reason.Trim(),
            ExpiresAt = expiresAt,
            CreatedBy = createdBy.Trim()
        };
    }

    /// <summary>현재 시각 기준 유효한 제재인지</summary>
    public bool IsActiveAt(DateTime nowUtc) => ExpiresAt is null || ExpiresAt > nowUtc;

    /// <summary>제재 즉시 해제 — 만료 시각을 현재로 당김 (이력 보존)</summary>
    public void Lift(DateTime nowUtc)
    {
        if (!IsActiveAt(nowUtc))
        {
            return;
        }

        ExpiresAt = nowUtc;
    }
}