// Hook: AfterPacketGeneration
// Remove worksheets that have no data after the packet was assembled.
//
// Empty sheets usually mean a merge step produced no rows for that segment.
// If removing the empties leaves the workbook with zero sheets, that is
// almost always a configuration mistake worth catching before distribution.

if (Workbook == null)
{
    AddError($"No workbook available for '{OutputName}'; cannot validate packet.");
    return;
}

var toRemove = new List<string>();

foreach (Worksheet sheet in Workbook.Worksheets)
{
    if (sheet.Cells.MaxDataRow < 0 && sheet.Cells.MaxDataColumn < 0)
        toRemove.Add(sheet.Name);
}

foreach (var name in toRemove)
{
    Workbook.Worksheets.RemoveAt(name);
    Logger.LogInformation($"Removed empty sheet '{name}' from '{OutputName}'.");
}

if (Workbook.Worksheets.Count == 0)
{
    AddError($"Packet '{OutputName}' has no sheets after empty-sheet cleanup; refusing to distribute.");
}

if (toRemove.Count > 0)
{
    AddWarning($"Removed {toRemove.Count} empty sheet(s) from '{OutputName}': {string.Join(", ", toRemove)}.");
}