using System.ComponentModel.DataAnnotations;

namespace Domain.Entities.Stocks;

/// <summary>
/// SEIBro 파생결합증권 발행내역 (getDerivCombiIssuInfo) — ELS/ELB/DLS/DLB 발행종목 (Wave 5). 자연키 UNIQUE (Isin).
/// DerivMaster(getDerivCombiIsinInfo) rolling 의 발견 소스 — 발행일(ISSU_DT) × 종류(SECN_KACD{4101/4102/4301/4302}) 날짜 스윕으로 신규 ISIN 을 찾는다.
/// 응답에 없는 SecnKacd·IssuDt 는 요청 파라미터를 배치가 스탬핑한다(응답 필드는 Isin·KorSecnNm·IssucoCustno 3종뿐).
/// </summary>
public class DerivIssuance
{
    [Key]
    public int ID { get; private set; }

    /// <summary>종목코드 (ISIN)</summary>
    public string Isin { get; private set; } = default!;

    /// <summary>한글종목명 (KOR_SECN_NM)</summary>
    public string? KorSecnNm { get; private set; }

    /// <summary>발행회사고객번호 (ISSUCO_CUSTNO)</summary>
    public int? IssucoCustno { get; private set; }

    /// <summary>종목종류코드 (SECN_KACD, 요청값 스탬핑) — 4101ELS 4102ELB 4301DLS 4302DLB</summary>
    public string SecnKacd { get; private set; } = default!;

    /// <summary>발행일자 (ISSU_DT, 요청값 스탬핑)</summary>
    public DateOnly IssuDt { get; private set; }

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

    private DerivIssuance() { }

    public static DerivIssuance Create(string isin, string? korSecnNm, int? issucoCustno, string secnKacd, DateOnly issuDt)
    {
        if (string.IsNullOrWhiteSpace(isin))
        {
            throw new ArgumentException("isin required", nameof(isin));
        }

        return new DerivIssuance
        {
            Isin = isin.Trim(),
            KorSecnNm = Trimmed(korSecnNm),
            IssucoCustno = issucoCustno,
            SecnKacd = secnKacd.Trim(),
            IssuDt = issuDt
        };
    }

    /// <summary>재수집 반영 — 변경 필드가 있을 때만 UpdatedAt 갱신 (자연키 Isin 은 불변)</summary>
    public void Update(string? korSecnNm, int? issucoCustno, string secnKacd, DateOnly issuDt)
    {
        var changed = false;

        changed |= Set(Trimmed(korSecnNm), KorSecnNm, v => KorSecnNm = v);
        changed |= Set(issucoCustno, IssucoCustno, v => IssucoCustno = v);
        changed |= Set(secnKacd.Trim(), SecnKacd, v => SecnKacd = v);
        changed |= Set(issuDt, IssuDt, v => IssuDt = v);

        if (changed)
        {
            UpdatedAt = DateTime.UtcNow;
        }
    }

    private static string? Trimmed(string? value)
    {
        return string.IsNullOrWhiteSpace(value) ? null : value.Trim();
    }

    private static bool Set<T>(T incoming, T current, Action<T> assign)
    {
        if (EqualityComparer<T>.Default.Equals(incoming, current))
        {
            return false;
        }

        assign(incoming);
        return true;
    }
}