namespace Admin.NET.Plugin.AiDOP.DataPlatform.Sequence;

/// <summary>单号格式化纯函数（可单测，无 DB）。语义对齐 pr_SFM_GetOrdNbr。</summary>
public static class NbrSequenceFormatter
{
    public static string NormalizeDateFormat(string? dateFormatWithCommas) =>
        string.IsNullOrWhiteSpace(dateFormatWithCommas)
            ? string.Empty
            : dateFormatWithCommas.Replace(",", "", StringComparison.Ordinal).Trim();

    /// <summary>
    /// 根据规范化后的日期格式（无逗号）计算周期键与拼进号码的日期段。
    /// </summary>
    public static (DateTime nbrDate, string nbrDateStr) ResolvePeriod(string normalizedFormat, DateTime now)
    {
        var fmt = (normalizedFormat ?? string.Empty).Trim();
        if (fmt.Length == 0)
            return (now.Date, string.Empty);

        if (fmt.Equals("YY", StringComparison.OrdinalIgnoreCase))
            return (new DateTime(now.Year, 1, 1), now.ToString("yy"));
        if (fmt.Equals("YYYY", StringComparison.OrdinalIgnoreCase))
            return (new DateTime(now.Year, 1, 1), now.ToString("yyyy"));
        if (fmt.Equals("YYMM", StringComparison.OrdinalIgnoreCase))
            return (new DateTime(now.Year, now.Month, 1), now.ToString("yyMM"));
        if (fmt.Equals("YYYYMM", StringComparison.OrdinalIgnoreCase))
            return (new DateTime(now.Year, now.Month, 1), now.ToString("yyyyMM"));
        if (fmt.Equals("YYMMDD", StringComparison.OrdinalIgnoreCase))
            return (now.Date, now.ToString("yyMMdd"));

        // YYYYMMDD 及其他 → 当天 + yyyyMMdd
        return (now.Date, now.ToString("yyyyMMdd"));
    }

    public static int ResolvePadWidth(decimal maxValue)
    {
        var s = ((long)maxValue).ToString();
        return Math.Max(1, s.Length);
    }

    public static string BuildNumber(string pre1, string pre2, string pre3, string dateStr, long serial, int padWidth)
    {
        var serialText = serial.ToString();
        if (serialText.Length > padWidth)
            throw new InvalidOperationException($"单号序号位数超出补零宽度：serial={serial}, width={padWidth}");
        return pre1 + pre2 + pre3 + dateStr + serialText.PadLeft(padWidth, '0');
    }

    public static IReadOnlyList<string> BuildRange(
        string pre1, string pre2, string pre3, string dateStr,
        long firstSerial, int count, int padWidth)
    {
        if (count <= 0) throw new ArgumentOutOfRangeException(nameof(count));
        var list = new List<string>(count);
        for (var i = 0; i < count; i++)
            list.Add(BuildNumber(pre1, pre2, pre3, dateStr, firstSerial + i, padWidth));
        return list;
    }
}