using Godot;
using System;
using Godot.Collections;

namespace BITKit.UX
{
	public partial class UXTabViewService : Control
	{
		[ExportCategory(Constant.Header.Settings)]
		[Export(PropertyHint.Range, "0,100")]
		private int currentIndex
		{
			get=>_currentIndex;
			set => SetIndex(value);
		}
		[Export] private int initialIndex;
		[ExportCategory(Constant.Header.Components)]
		[Export] private Array<Button> tabs;
		[Export] private TabContainer tabContainer;
		private ButtonGroup _buttonGroup;
		
		private int _currentIndex;

		public override void _Ready()
		{
			if (_isReady is false) return;
			_buttonGroup = new ButtonGroup();

			for (var i = 0; i < tabs.Count; i++)
			{
				var tab = tabs[i];
				var _i = i;
				tab.Pressed += () => { SetIndex(_i); };
			}

			var index = (Engine.IsEditorHint(), currentIndex, initialIndex) switch
			{
				(true,_,_)=>currentIndex,
				(false,_,>-1)=>initialIndex,
				(_,_,-1)=>-1,
				_ => -1
			};
			SetIndex(index);
		}

		private void SetIndex(int value)
		{
			if (_isReady is false) return;
			if (value < 0) return;
			
			EnsureConfiguration();

			var max = tabContainer.GetChildCount() - 1;
			value = Mathf.Clamp(value, 0, max < 0 ?  0 : max );
			
			_currentIndex = value;
			tabContainer.CurrentTab = value;

			foreach (var tab in tabs)
			{
				tab.ButtonPressed = false;
			}
			if (tabs.TryGetElementAt(value, out var button))
			{
				button.ButtonPressed = true;
			}
		}

		private void EnsureConfiguration()
		{
			if (_isReady is false) return;
			tabContainer.TabsVisible = false;
			
			foreach (var tab in tabs)
			{
				tab.ButtonGroup = _buttonGroup;
			}
		}

		private bool _isReady => IsNodeReady() && tabContainer is not null & tabs is not null;
	}
}