// submission
if (isset($_POST['submit2']))
{
  $rows     = $_POST['rows'];
  $shifts   = array(3,1,2);

  // set the timestamp to be midnight today so data will always be between startDate and endDat
  $year   = strftime("%Y", $startDate);
  $month  = strftime("%m", $startDate);
  $day    = strftime("%d", $startDate);
  $date  = mktime(24, 0, 0, $month, $day, $year);
  
  // populate columns
  $columns  = array();
  array_push($columns, "date", "group");
  for ($i=0; $i<count($shifts); $i++)
  {
    $shift = $shifts[$i];
    array_push($columns, "mil$shift", "meters$shift", "product$shift", "wasteProd$shift", "wastePer$shift", "eff$shift");
  }
  array_push($columns, "line", "avgLine", "wasteTotal",  "wasteProd3",  "wastePercent",  "avgEff");
  
  // populate values
  $values   = array();
  for ($i=0; $i<$rows; $i++)
  {
    $rows2  = $_POST['subRows'.$i];
    $group  = $_POST['group'.$i];
    for ($j=0; $j<$rows2; $j++)
    {
      $rowValues = array($date, $group);
      for ($k=0; $k<count($shifts); $k++)
      {
        $shift      = $shifts[$k];
                
        $mil        = $_POST['mil'.$shift.'_'.$i.'_'.$j];
        $meters     = $_POST['meters'.$shift.'_'.$i.'_'.$j];
        $product    = $_POST['product'.$shift.'_'.$i.'_'.$j];
        $wasteProd  = $_POST['wasteProd'.$shift.'_'.$i.'_'.$j];
        $wastePer   = $_POST['wastePer'.$shift.'_'.$i.'_'.$j];
        $eff        = $_POST['eff'.$shift.'_'.$i.'_'.$j];
        
        array_push($rowValues, "$mil", "$meters", "$product", "$wasteProd", "$wastePer", "$eff");
      }
      $line         = $_POST['line_'.$i.'_'.$j];
      $avgLine      = $_POST['avgLine_'.$i.'_'.$j];
      $wasteTotal   = $_POST['wasteTotal_'.$i.'_'.$j];
      $wastePercent = $_POST['wastePercent_'.$i.'_'.$j];
      $avgEff       = $_POST['avgEff_'.$i.'_'.$j];
      
      array_push($rowValues, "$line", "$avgLine", "$wasteTotal", "$wastePercent", "$avgEff");
      array_push($values, $rowValues);
    }
  }
  
  // INSERT INTO table_name VALUES (value1, value2,....)
  if ($stage == "new")
  {
    for ($i=0; $i<count($values); $i++)
    {
      $sql = "INSERT INTO mpsr VALUES (";
      for ($j=0; $j<count($values[$i]); $j++)
      {
        $sql .= "'".$values[$i][$j]."'";
        if ($j != count($values[$i])-1) $sql .= ",";
      }
      $sql .= ")";
      echo "$sql<br>";
    }
  }
  // UPDATE table_name SET column_name = new_value, column_name2 = new_value2,.... WHERE column_name = some_value
  elseif ($stage == "edit")
  {
    for ($i=0; $i<count($values); $i++)
    {
      $sql = "UPDATE mpsr SET ";
      for ($j=0; $j<count($values[$i]); $j++)
      {
        $sql .= "$columns[$j] = '".$values[$i][$j]."'";
        if ($j != count($values[$i])-1) $sql .= ",";
      }
      $sql .= "WHERE column_name = something (need to incorporate autoincreasing id)";
      echo "$sql<br>";
    }
  }
  
}