GES_PAC

using System.Globalization;

namespace GES_PAC.Controls

{

    public class DoubleEntry : Entry

    {

        public static readonly BindableProperty DoubleValueProperty =

            BindableProperty.Create(

                nameof(DoubleValue),

                typeof(double?),

                typeof(DoubleEntry),

                default(double?),

                BindingMode.TwoWay,

                propertyChanged: OnDoubleValueChanged);

        public double? DoubleValue

        {

            get => (double?)GetValue(DoubleValueProperty);

            set => SetValue(DoubleValueProperty, value);

        }

        public DoubleEntry()

        {

            Keyboard = Keyboard.Numeric;

            PlaceholderColor = Colors.LightGray;

            TextColor = Colors.Black;

            Placeholder = "0,0";

            FontSize = 16;

            TextChanged += OnTextChanged;

        }

        private static void OnDoubleValueChanged(BindableObject bindable, object oldValue, object newValue)

        {

            if (bindable is DoubleEntry entry && newValue is double val)

            {

                var str = val.ToString(CultureInfo.CurrentCulture);

                if (entry.Text != str)

                    entry.Text = str;

            }

        }

        private void OnTextChanged(object sender, TextChangedEventArgs e)

        {

            var input = e.NewTextValue;

            if (string.IsNullOrWhiteSpace(input))

                return;

            if (input.StartsWith(","))

            {

                MainThread.BeginInvokeOnMainThread(() =>

                {

                    TextChanged -= OnTextChanged;

                    Text = "0" + input;

                    TextChanged += OnTextChanged;

                });

                return;

            }

            if (double.TryParse(input, NumberStyles.Float, CultureInfo.CurrentCulture, out double value))

            {

                SetValue(DoubleValueProperty, value);

            }

            else

            {

                SetValue(DoubleValueProperty, null);

            }

        }

    }

}