ANTOOZA-BACKEND/Domain/Entities/Paper/PaperLedger.cs

using System.ComponentModel.DataAnnotations;
using System.ComponentModel.DataAnnotations.Schema;
using Domain.Entities.Paper.ValueObject;

namespace Domain.Entities.Paper;

/// <summary>
/// 모의투자 계좌 입출금 감사 원장 — 지갑 토큰 ↔ 계좌 토큰 이동 이력 (d4 §③).
/// WalletTxRefID 로 지갑 거래(WalletTransaction.RefID)와 연결.
/// </summary>
public class PaperLedger
{
    [ForeignKey(nameof(AccountID))]
    public virtual PaperAccount Account { get; private set; } = null!;

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

    public int AccountID { get; private set; }

    public PaperLedgerType Type { get; private set; }

    /// <summary>이동 토큰 (18,0)</summary>
    public decimal TokenAmount { get; private set; }

    /// <summary>좌수 변화 (입금 +발행 / 출금 -소각, 18,8)</summary>
    public decimal UnitsDelta { get; private set; }

    /// <summary>연결된 지갑 거래 RefID</summary>
    public string? WalletTxRefID { get; private set; }

    /// <summary>이동 후 계좌 자유 토큰 잔액</summary>
    public decimal BalanceAfter { get; private set; }

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

    private PaperLedger() { }

    public static PaperLedger Create(
        int accountID,
        PaperLedgerType type,
        decimal tokenAmount,
        decimal unitsDelta,
        string? walletTxRefID,
        decimal balanceAfter
    ) {
        if (accountID <= 0)
        {
            throw new ArgumentOutOfRangeException(nameof(accountID));
        }

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

        return new PaperLedger
        {
            AccountID = accountID,
            Type = type,
            TokenAmount = tokenAmount,
            UnitsDelta = unitsDelta,
            WalletTxRefID = walletTxRefID,
            BalanceAfter = balanceAfter
        };
    }

    /// <summary>
    /// 신규 계좌(ID 미확정) 케이스 — Account 내비게이션으로 생성해 EF 가 저장 시 FK 를 자동 채우게 한다.
    /// </summary>
    public static PaperLedger CreateFor(
        PaperAccount account,
        PaperLedgerType type,
        decimal tokenAmount,
        decimal unitsDelta,
        string? walletTxRefID,
        decimal balanceAfter
    ) {
        ArgumentNullException.ThrowIfNull(account);

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

        return new PaperLedger
        {
            Account = account,
            Type = type,
            TokenAmount = tokenAmount,
            UnitsDelta = unitsDelta,
            WalletTxRefID = walletTxRefID,
            BalanceAfter = balanceAfter
        };
    }
}