using System.Drawing.Drawing2D;

namespace UI
{
    public class RoundComboBox : UserControl
    {
        private ComboBox _comboBox = null!;
        public int Radius { get; set; } = 4;
        public Color BorderColor { get; set; } = Color.LightGray;
        public Color FocusColor { get; set; } = Color.Blue;
        private bool _focused;

        public ComboBoxStyle DropDownStyle
        {
            get => _comboBox.DropDownStyle;
            set => _comboBox.DropDownStyle = value;
        }

        public ComboBox.ObjectCollection Items => _comboBox.Items;

        public object? SelectedItem
        {
            get => _comboBox.SelectedItem;
            set => _comboBox.SelectedItem = value;
        }

        public int SelectedIndex
        {
            get => _comboBox.SelectedIndex;
            set => _comboBox.SelectedIndex = value;
        }

        public override string Text
        {
            get => _comboBox.Text;
            set => _comboBox.Text = value;
        }

        public new Color BackColor
        {
            get => base.BackColor;
            set { base.BackColor = value; if (_comboBox != null) _comboBox.BackColor = value; }
        }

        public new event EventHandler? SelectedIndexChanged
        {
            add => _comboBox.SelectedIndexChanged += value;
            remove => _comboBox.SelectedIndexChanged -= value;
        }

        public RoundComboBox()
        {
            DoubleBuffered = true;
            base.BackColor = Color.White;

            _comboBox = new ComboBox
            {
                //BorderStyle = BorderStyle.None,
                Font = new Font("Segoe UI", 9f),
                BackColor = Color.White,
                DropDownStyle = ComboBoxStyle.DropDownList,
                FlatStyle = FlatStyle.Flat
            };

            _comboBox.GotFocus += (s, e) => { _focused = true; Invalidate(); };
            _comboBox.LostFocus += (s, e) => { _focused = false; Invalidate(); };
            _comboBox.TextChanged += (s, e) => OnTextChanged(e);
            _comboBox.Leave += (s, e) => OnLeave(e);

            Controls.Add(_comboBox);
            SizeChanged += (s, e) => AjustarComboBox();
        }

        private void AjustarComboBox()
        {
            _comboBox.Width = Width - 12;
            _comboBox.Location = new Point(6, (Height - _comboBox.PreferredHeight) / 2);
        }
        public object? DataSource
        {
            get => _comboBox.DataSource;
            set => _comboBox.DataSource = value;
        }

        public string DisplayMember
        {
            get => _comboBox.DisplayMember;
            set => _comboBox.DisplayMember = value;
        }

        public string ValueMember
        {
            get => _comboBox.ValueMember;
            set => _comboBox.ValueMember = value;
        }

        public object? SelectedValue
        {
            get => _comboBox.SelectedValue;
            set => _comboBox.SelectedValue = value;
        }

        protected override void OnPaint(PaintEventArgs e)
        {
            e.Graphics.SmoothingMode = SmoothingMode.AntiAlias;
            using var path = GetPath(new Rectangle(0, 0, Width - 1, Height - 1), Radius);
            using var brush = new SolidBrush(BackColor);
            e.Graphics.FillPath(brush, path);
            using var pen = new Pen(_focused ? FocusColor : BorderColor, _focused ? 1.5f : 1f);
            e.Graphics.DrawPath(pen, path);
        }

        private static GraphicsPath GetPath(Rectangle r, int rad)
        {
            var path = new GraphicsPath();
            int d = rad * 2;
            path.AddArc(r.X, r.Y, d, d, 180, 90);
            path.AddArc(r.Right - d, r.Y, d, d, 270, 90);
            path.AddArc(r.Right - d, r.Bottom - d, d, d, 0, 90);
            path.AddArc(r.X, r.Bottom - d, d, d, 90, 90);
            path.CloseFigure();
            return path;
        }
    }
}