/// <summary>
/// Saves the data to the database if it has not already been added
/// </summary>
/// <typeparam name="T">The generic type</typeparam>
/// <param name="data">The data is passed as a ref so that it will contain the database value if the object alreadt exists.
/// This prevents adding duplicate values
/// </param>
/// <param name="checkIfExists">The predicate expression used in the LINQ query to check for existing values</param>
private void AddToDb <T>(T data, Expression <Func <T, bool> > checkIfExists = default) where T : class
{
// Check if the entity already exists in the database
Expression <Func <T, bool> > predicate = checkIfExists ?? (_ => false);
var existingType = ctx.Set <T>().FirstOrDefault(predicate);
if (existingType == null)
{
var result = ctx.Set <T>().Add(data);
if (result.State == EntityState.Added)
{
ctx.SaveChanges();
}
}
}
