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

namespace NSD
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        private void Form1_Load(object sender, EventArgs e)
        {
            textBox1.Text = "";
            textBox2.Text = "";
            listBox1.Items.Clear();
            textBox1.Focus();
        }

        private void button_close_Click(object sender, EventArgs e)
        {
            this.Close();
        }

        private void textBox1_KeyPress(object sender, KeyPressEventArgs e)
        {
            if (!((e.KeyChar >= 48 && e.KeyChar <= 57) || (e.KeyChar == 8)))
            {
                e.KeyChar = Convert.ToChar(0);
            }
        }

        private void textBox2_KeyPress(object sender, KeyPressEventArgs e)
        {
            if (!((e.KeyChar >= 48 && e.KeyChar <= 57) || (e.KeyChar == 8)))
            {
                e.KeyChar = Convert.ToChar(0);
            }
        }

        private void button_vypocet_Click(object sender, EventArgs e)
        {
            uint c1, c2, zb, nsd;
            string nsd_vystup;

            if (textBox1.Text == "" || textBox2.Text == "")
            {
                MessageBox.Show("Musíte zadat čísla!", "Varování", MessageBoxButtons.OK, MessageBoxIcon.Warning);
                return;                
            }
            else
            {
                try
                {
                    c1 = Convert.ToUInt32(textBox1.Text);
                    c2 = Convert.ToUInt32(textBox2.Text);
                }
                catch (OverflowException)
                {
                    MessageBox.Show("Zadejte menší čísla!", "Informace", MessageBoxButtons.OK, MessageBoxIcon.Information);
                    return;
                }

                if (c1 == 0 || c2 == 0)
                {
                    MessageBox.Show("Pro nulu nemá smysl!", "Chyba", MessageBoxButtons.OK, MessageBoxIcon.Error);
                    return;
                }
                else
                {
                        zb = 1;
                        while (zb != 0)
                        {
                           zb = c1 % c2;
                           c1 = c2;
                           c2 = zb;
                         }

                    nsd = c1;
                    nsd_vystup = Convert.ToString(nsd);
                    listBox1.Items.Add("NSD(" + textBox1.Text + "," + textBox2.Text + ") = " + nsd_vystup);
                }

            }

        }

        private void pictureBox1_Click(object sender, EventArgs e)
        {
            System.Diagnostics.Process.Start("https://cs.wikipedia.org/wiki/Eukleid%C5%AFv_algoritmus");
        }

        private void button_vymaz_Click(object sender, EventArgs e)
        {
            textBox1.Text = "";
            textBox2.Text = "";
            textBox1.Focus();        
        }
    }
}