using System.ComponentModel.DataAnnotations;
using System.ComponentModel.DataAnnotations.Schema;

namespace Domain.Entities.Members.Logs;

/// <summary>
/// 경험치 변동 내역
/// </summary>
public class MemberExpLog
{
    [ForeignKey(nameof(MemberID))]
    public virtual Member Member { get; private set; } = null!;

    [ForeignKey(nameof(BroadcastSessionID))]
    public virtual BroadcastSession? BroadcastSession { get; private set; }

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

    public int MemberID { get; private set; }

    /// <summary>방송 세션 단위로 리더보드 집계 (null = 방송 외 적립)</summary>
    public int? BroadcastSessionID { get; private set; }

    /// <summary>채널 문맥 (channel 단위 조회용, null = 전역)</summary>
    public int? ChannelID { get; private set; }

    public string Reason { get; private set; } = default!;

    public int Amount { get; private set; }

    public long Balance { get; private set; }

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

    private MemberExpLog() { }

    private MemberExpLog(int memberID, string reason, int amount, long balance, int? broadcastSessionID, int? channelID)
    {
        if (memberID <= 0)
        {
            throw new ArgumentOutOfRangeException(nameof(memberID));
        }

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

        if (reason.Length > 200)
        {
            throw new ArgumentOutOfRangeException(nameof(reason));
        }

        MemberID = memberID;
        Reason = reason;
        Amount = amount;
        Balance = balance;
        BroadcastSessionID = broadcastSessionID;
        ChannelID = channelID;
        CreatedAt = DateTime.UtcNow;
    }

    public static MemberExpLog Create(int memberID, string reason, int amount, long balance)
    {
        return new(memberID, reason, amount, balance, null, null);
    }

    /// <summary>방송 중 적립 (채팅/후원 XP) — 리더보드 집계 대상</summary>
    public static MemberExpLog CreateForBroadcast(int memberID, string reason, int amount, long balance, int broadcastSessionID, int channelID)
    {
        return new(memberID, reason, amount, balance, broadcastSessionID, channelID);
    }
}