namespace Common.UI.Controls
{
    using Common.UI.ViewModels;

    using System.Collections.Generic;
    using System.Linq;
    using System.Windows;
    using System.Windows.Controls;

    public partial class GridLayout : Grid
    {
        public static readonly DependencyProperty ItemsSourceProperty = DependencyProperty.Register(
              name: nameof(ItemsSource)
            , propertyType: typeof(IEnumerable<GridItem>)
            , ownerType: typeof(GridLayout)
            , typeMetadata: new FrameworkPropertyMetadata(null, ItemsSourceChanged));

        public GridLayout() => this.InitializeComponent();

        public IEnumerable<GridItem> ItemsSource
        {
            get => this.GetValue(ItemsSourceProperty) as IEnumerable<GridItem>;
            set => this.SetValue(ItemsSourceProperty, value);
        }

        private void UpdateItemsCollection()
        {
            if (this.ItemsSource?.Count() <= 0)
            {
                return;
            }

            this.Children.Clear();
            this.RowDefinitions.Clear();
            this.ColumnDefinitions.Clear();

            var rowsCount = this.ItemsSource.Max(x => x.Row) + 1;

            for (var i = 0; i < rowsCount; i++)
            {
                this.RowDefinitions.Add(new RowDefinition { Height = GridLength.Auto });
            }

            var columnsCount = this.ItemsSource.Max(x => x.Column) + 1;

            for (var i = 0; i < columnsCount; i++)
            {
                this.ColumnDefinitions.Add(new ColumnDefinition { Width = new GridLength(1, GridUnitType.Star)/*, MinWidth = 200*/ });
            }

            foreach (var item in this.ItemsSource)
            {
                var content = new ContentControl { Content = item };

                SetRow(content, item.Row);
                SetRowSpan(content, item.RowSpan);
                SetColumn(content, item.Column);
                SetColumnSpan(content, item.ColumnSpan);

                this.Children.Add(content);
            }
        }

        private static void ItemsSourceChanged(DependencyObject control, DependencyPropertyChangedEventArgs args)
        {
            if (control is GridLayout gridLayout)
            {
                gridLayout.Dispatcher.Invoke(gridLayout.UpdateItemsCollection);
            }
        }
    }
}