using System;
using System.ComponentModel;
using System.Windows;
using System.Windows.Controls;

namespace DTS.Common.Controls
{
    public class DynamicGrid : Grid, INotifyPropertyChanged
    {
        #region INotifyPropertyChanged
        public event PropertyChangedEventHandler PropertyChanged;
        protected bool SetProperty<T>(ref T storage, T value, string propertyName = null)
        {
            if (Equals(storage, value)) return false;

            storage = value;
            OnPropertyChanged(propertyName);
            return true;
        }
        protected void OnPropertyChanged(string propertyName = null)
        {
            PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName));
        }
        #endregion

        public DynamicGrid()
            : base()
        {
            Refresh();            
        }

        protected override void OnVisualChildrenChanged(DependencyObject visualAdded, DependencyObject visualRemoved)
        {
            base.OnVisualChildrenChanged(visualAdded, visualRemoved);

            Refresh();
        }

        public void Refresh()
        {
            ColumnDefinitions.Clear();
            for (byte i = 0; i < GridColumns; i++)
            {
                ColumnDefinitions.Add(new ColumnDefinition());
                if (i + 1 != GridColumns)
                {
                    ColumnDefinitions[i].Width = new GridLength(1, GridUnitType.Auto);
                }
                else
                {
                    ColumnDefinitions[i].Width = new GridLength(1, GridUnitType.Star);
                }

            }

            var curRow = 0;
            var curCol = 0;

            RowDefinitions.Clear();

            if (Children != null)
            {
                foreach (UIElement curChild in Children)
                {
                    if(0 == curCol)
                    {
                        // We're on the first column, we need a new row for the child
                        RowDefinitions.Add(new RowDefinition() { Height = new GridLength(1, GridUnitType.Auto) });
                    }

                    // Set the child to its row and column
                    SetRow(curChild, curRow);
                    SetColumn(curChild, curCol);

                    // Iderate
                    if (curCol < GridColumns-1)
                    {
                        // We're moving to the next column
                        curCol++;
                    }
                    else
                    {
                        // We're at the end, go back to clumn 0
                        curCol = 0;
                        curRow++;
                    }
                    
                }
            }
            RowDefinitions.Add(new RowDefinition() { Height = new GridLength(1, GridUnitType.Star) });
        }


        private byte _columns = 2;
        public byte GridColumns
        {
            get => _columns;
            set { _columns = value; Refresh(); }
        }
    }

}