function doPost(e) {
  try {
    var ss   = SpreadsheetApp.getActiveSpreadsheet();
    var sheet = ss.getSheetByName('IBI Pricing Calculator')
                || ss.insertSheet('IBI Pricing Calculator');
    var data  = JSON.parse(e.postData.contents);

    // Write header row if sheet is empty
    if (sheet.getLastRow() === 0) {
      sheet.appendRow(data.headers);
      sheet.getRange(1, 1, 1, data.headers.length)
           .setFontWeight('bold')
           .setBackground('#7c3aed')
           .setFontColor('#ffffff');
      sheet.setFrozenRows(1);
    }

    sheet.appendRow(data.values);

    return ContentService
      .createTextOutput(JSON.stringify({status:'ok'}))
      .setMimeType(ContentService.MimeType.JSON);
  } catch(err) {
    return ContentService
      .createTextOutput(JSON.stringify({status:'error', message:err.toString()}))
      .setMimeType(ContentService.MimeType.JSON);
  }
}

function doGet(e) {
  return ContentService
    .createTextOutput(JSON.stringify({status:'ok', message:'IBI Calculator endpoint active'}))
    .setMimeType(ContentService.MimeType.JSON);
}