static public double FuelDeduction(double fuelLtr, string table)
{
double usedFuelPerLTRPrice = 0;
double fuelToDeduct = fuelLtr;
double fuelInTank = 0;
double totalUsableFuel = 0;
string fuelRef = "";
SQLiteDataReader reader;
SQLiteCommand sqlite_cmd;
sqlite_cmd = GlobalFunctions.Connect().CreateCommand();
sqlite_cmd.CommandText = "SELECT LTRUsable FROM " + table + " WHERE LTRUsable > 0;";
reader = sqlite_cmd.ExecuteReader();
while (reader.Read())
{
totalUsableFuel = totalUsableFuel + reader.GetDouble(0);
}
if (fuelToDeduct > totalUsableFuel)
{
MessageBox.Show("There is not enough Fuel in Tank");
return(0);
}
reader.Close();
sqlite_cmd.CommandText = "SELECT Reference,LTRUsable, PerLTRPRice FROM " + table + " WHERE LTRUsable > 0 limit 1;";
reader = sqlite_cmd.ExecuteReader();
while (reader.Read())
{
fuelRef = reader.GetValue(0).ToString();
fuelInTank = reader.GetDouble(1);
usedFuelPerLTRPrice = reader.GetDouble(2);
break;
}
reader.Close();
if (fuelInTank <= 0)
{
MessageBox.Show("The Fuel tank is empty!");
return(0);
}
if (fuelInTank >= fuelToDeduct)
{
fuelInTank = fuelInTank - fuelToDeduct;
fuelTankUpdate(fuelRef, fuelInTank, table);
usedFuelTotalCost = usedFuelTotalCost + (usedFuelPerLTRPrice * fuelToDeduct);
}
else
{
double difference = fuelInTank - fuelToDeduct;
difference = difference * -1;
usedFuelTotalCost = usedFuelTotalCost + (usedFuelPerLTRPrice * fuelInTank);
fuelInTank = 0;
fuelTankUpdate(fuelRef, fuelInTank, table);
FuelDeduction(difference, table);
}
GlobalFunctions.CloseConnection();
reader.Close();
return(usedFuelTotalCost);
}