using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;

using System;
using System.Windows.Forms;
using FormLibrary.Exceptions;

namespace FormLibrary
{
    public partial class IntegerInputControl : UserControl
    {
        public event EventHandler? ValueChanged;

        public event EventHandler? CheckBoxChanged;

        public IntegerInputControl()
        {
            InitializeComponent();

            checkBoxNull.CheckedChanged += CheckBoxNull_CheckedChanged;
            textBoxInput.TextChanged += TextBoxInput_TextChanged;
        }

        public int? Value
        {
            get
            {
                if (checkBoxNull.Checked)
                {
                    return null;
                }
                else
                {
                    if (string.IsNullOrWhiteSpace(textBoxInput.Text))
                    {
                        throw new EmptyValueException();
                    }

                    if (int.TryParse(textBoxInput.Text, out int result))
                    {
                        return result;
                    }
                    else
                    {
                        throw new InvalidValueTypeException();
                    }
                }
            }
            set
            {
                if(value is not null) 
                {
                    textBoxInput.Text = value.ToString();
                }
                checkBoxNull.Checked = value is null;
            }
        }

        private void CheckBoxNull_CheckedChanged(object sender, EventArgs e)
        {
            textBoxInput.Enabled = !checkBoxNull.Checked;
            if (checkBoxNull.Checked)
            {
                textBoxInput.Text = string.Empty;
            }
            CheckBoxChanged?.Invoke(this, EventArgs.Empty);
        }

        private void TextBoxInput_TextChanged(object sender, EventArgs e)
        {
            ValueChanged?.Invoke(this, EventArgs.Empty);
        }
    }
}