using System.Collections.ObjectModel;
using DragNDrop.Model;

namespace DragNDrop;

public partial class OrganizeNounoursPage : ContentPage
{
	public ObservableCollection<Nounours> NounoursCollection { get; set; } = new ObservableCollection<Nounours>()
	{
		new Nounours(42, "Chewbacca"),
		new Nounours(43, "Yoda"),
		new Nounours(44, "Ewok"),
		new Nounours(45, "Jabba the Hutt"),
		new Nounours(666, "Chucky")
	};

	public OrganizeNounoursPage()
	{
		InitializeComponent();
		BindingContext = this;
	}

	private void OnDragStarting(object sender, DragStartingEventArgs e)
	{
		e.Data.Properties["value"] = (sender as Element)?.BindingContext;
	}
	
	private void OnDrop(object sender, DropEventArgs e)
	{
		if ((sender as Element)?.BindingContext is not Nounours receivingElement) return;
		if (e.Data.Properties["value"] as Nounours is not Nounours draggedElement) return;

		int draggedIndex = NounoursCollection.IndexOf(draggedElement);
		if (draggedIndex > -1)
		{
			NounoursCollection.RemoveAt(draggedIndex);
		}

		int receivingIndex = NounoursCollection.IndexOf(receivingElement);
		if (receivingIndex == -1) throw new ArgumentNullException("There should be a receiving element");

		if (receivingIndex >= draggedIndex)
		{
			NounoursCollection.Insert(receivingIndex + 1, draggedElement);
		}
		else
		{
			NounoursCollection.Insert(receivingIndex, draggedElement);
		}
	}
}