using static System.Console;

public class ExampleEinaError01
{
    private static bool RegisteredErrors = false;
    private static Eina.Error MyErrorNegative;
    private static Eina.Error MyErrorNull;

    private static void testFunc(int n, string s)
    {
        if (!RegisteredErrors)
        {
            MyErrorNegative = Eina.Error.Register("Negative number");
            MyErrorNull = Eina.Error.Register("NULL pointer");
            RegisteredErrors = true;
        }

        if (n < 0)
        {
            Eina.Error.Set(MyErrorNegative);
            return;
        }

        if (s == null)
        {
            Eina.Error.Set(MyErrorNull);
            return;
        }
    }

    public static void Main()
    {
        Eina.Config.Init();
        Efl.Eo.Config.Init();

        // Handling Eina_Error with exception
        try
        {
            testFunc(-1, "abc");
            Eina.Error.RaiseIfOccurred();
        }
        catch(Efl.EflException e)
        {
            WriteLine($"Caught error: {e.Message}");
        }

        // Handling Eina_Error directly
        testFunc(42, null);
        Eina.Error err = Eina.Error.Get();
        if (err != 0)
        {
            WriteLine($"Error set: {err.Message}");
        }
        Eina.Error.Clear();

        // No error set
        try
        {
            testFunc(42, "abc");

            Eina.Error.RaiseIfOccurred();

            err = Eina.Error.Get();
            WriteLine($"Really no error? {err == Eina.Error.NO_ERROR}.");
        }
        catch
        {
            WriteLine("Unspected error!!!");
        }

        WriteLine("No error message is empty string: \"{0}\"", Eina.Error.NO_ERROR.Message);
        WriteLine("No error message is empty string: \"{0}\"", Eina.Error.MsgGet(0));
    }
}