using System;
using System.Text;
using System.Windows.Forms;

namespace PasswordGenerator
{
    public partial class Form1 : Form
    {
        const string charsUpper = "ABCDEFGHIJKLMNOPQRSTUVWXYZ";
        const string charsLower = "abcdefghijklmnopqrstuvwxyz";
        const string charsNumber = "0123456789";
        const string charsSymbols = "!@#$%^&*";
        private bool _loaded = false;

        public Form1()
        {
            InitializeComponent();

            _loaded = true;
            GeneratePassword();
        }

        public void GeneratePassword()
        {
            string chars =
                (UppercaseCheck.Checked ? charsUpper : "") +
                (LowercaseCheck.Checked ? charsLower : "") +
                (NumbersCheck.Checked ? charsNumber : "") +
                (SymbolsCheck.Checked ? charsSymbols : "");

            if (chars == "") { PasswordOutput.Text = ""; return; }

            StringBuilder password = new StringBuilder();
            Random random = new Random();

            for (int i = 0; i < LengthSlider.Value; i++)
            {
                password.Append(chars[random.Next(chars.Length)]);
            }

            PasswordOutput.Text = password.ToString();
        }

        private void LengthSlider_ValueChanged(object sender, System.EventArgs e)
        {
            if (!_loaded) return;

            LengthText.Text = $"Password Length: {LengthSlider.Value}";
            GeneratePassword();
        }

        private void CopyButton_Click(object sender, System.EventArgs e)
        {
            Clipboard.SetText(PasswordOutput.Text);
        }

        private void RegenerateButton_Click(object sender, System.EventArgs e) => GeneratePassword();
        private void UppercaseCheck_CheckedChanged(object sender, EventArgs e) => GeneratePassword();
        private void LowercaseCheck_CheckedChanged(object sender, EventArgs e) => GeneratePassword();
        private void NumbersCheck_CheckedChanged(object sender, EventArgs e) => GeneratePassword();
        private void SymbolsCheck_CheckedChanged(object sender, EventArgs e) => GeneratePassword();
        private void PresetLength8Button_Click(object sender, System.EventArgs e) => LengthSlider.Value = 8;
        private void PresetLength16Button_Click(object sender, System.EventArgs e) => LengthSlider.Value = 16;
        private void PresetLength32Button_Click(object sender, System.EventArgs e) => LengthSlider.Value = 32;
        private void PresetLength64Button_Click(object sender, System.EventArgs e) => LengthSlider.Value = 64;
        private void PresetLength128Button_Click(object sender, System.EventArgs e) => LengthSlider.Value = 128;
    }
}