using Sandbox;
using Sandbox.UI;
using Sandbox.UI.Construct;
using System;
namespace XGUI;

public partial class XGUIPopup : XGUIPanel
{
	/// <summary>
	/// Which panel triggered this popup. Set by <see cref="SetPositioning"/> or the constructor.
	/// </summary>
	public Panel PopupSource { get; set; }

	/// <summary>
	/// Currently selected option in the popup. Used internally for keyboard navigation.
	/// </summary>
	public Panel SelectedChild { get; set; }

	/// <summary>
	/// Positioning mode for this popup.
	/// </summary>
	public PositionMode Position { get; set; }

	/// <summary>
	/// Offset away from <see cref="PopupSource"/> based on <see cref="Position"/>.
	/// </summary>
	public float PopupSourceOffset { get; set; }

	/// <summary>
	/// Dictates where a <see cref="Popup"/> is positioned.
	/// </summary>
	public enum PositionMode
	{
		/// <summary>
		/// To the left of the source panel, centered.
		/// </summary>
		Left,

		/// <summary>
		/// To the left of the source panel, aligned to the bottom.
		/// </summary>
		LeftBottom,

		Right,
		RightBottom,

		/// <summary>
		/// Above the source panel, aligned to the left.
		/// </summary>
		AboveLeft,

		/// <summary>
		/// Below the source panel, aliging on the left. Do not stretch to size of <see cref="Popup.PopupSource"/>.
		/// </summary>
		BelowLeft,

		/// <summary>
		/// Below the source panel, centered horizontally.
		/// </summary>
		BelowCenter,

		/// <summary>
		/// Below the source panel, stretch to the width of the <see cref="Popup.PopupSource"/>.
		/// </summary>
		BelowStretch,

		/// <summary>
		/// Position where the mouse cursor is currently
		/// </summary>
		UnderMouse
	}

	public XGUIPopup()
	{
		AcceptsFocus = false;
	}

	/// <inheritdoc cref="SetPositioning"/>
	public XGUIPopup( Panel sourcePanel, PositionMode position, float offset )
	{
		SetPositioning( sourcePanel, position, offset );
		this.AddEventListener( "onmousedown", MouseDown );
		AcceptsFocus = false;
		if ( sourcePanel is ComboBox cb )
		{

			AcceptsFocus = true;
		}
		Focus();
	}

	public void UpdateStyle()
	{
		foreach ( var stylesheet in PopupSource.AllStyleSheets )
		{
			StyleSheet.Add( stylesheet );
		}
	}

	PositionMode Mode;

	/// <summary>
	/// Sets <see cref="PopupSource"/>, <see cref="Position"/> and <see cref="PopupSourceOffset"/>.
	/// Applies relevant CSS classes.
	/// </summary>
	/// <param name="sourcePanel">Which panel triggered this popup.</param>
	/// <param name="position">Desired positioning mode.</param>
	/// <param name="offset">Offset away from the <paramref name="sourcePanel"/>.</param>
	public void SetPositioning( Panel sourcePanel, PositionMode position, float offset )
	{
		Parent = sourcePanel;
		PopupSource = sourcePanel;
		Position = position;
		PopupSourceOffset = offset;
		Mode = position;
		AddClass( "dropdown-panel" );
		PositionMe();

		switch ( Position )
		{
			case PositionMode.Left:
				AddClass( "left" );
				break;

			case PositionMode.LeftBottom:
				AddClass( "left-bottom" );
				break;

			case PositionMode.AboveLeft:
				AddClass( "above-left" );
				break;

			case PositionMode.BelowLeft:
				AddClass( "below-left" );
				break;

			case PositionMode.BelowCenter:
				AddClass( "below-center" );
				break;

			case PositionMode.BelowStretch:
				AddClass( "below-stretch" );
				break;
		}
	}



	/// <summary>
	/// Header panel that holds <see cref="TitleLabel"/> and <see cref="IconPanel"/>.
	/// </summary>
	protected Panel Header;

	/// <summary>
	/// Label that dispalys <see cref="Title"/>.
	/// </summary>
	protected Label TitleLabel;

	/// <summary>
	/// Panel that dispalys <see cref="Icon"/>.
	/// </summary>
	protected IconPanel IconPanel;

	void CreateHeader()
	{
		if ( Header != null ) return;

		Header = Add.Panel( "header" );

		IconPanel = Header.Add.Icon( null );
		TitleLabel = Header.Add.Label( null, "title" );
	}

	/// <summary>
	/// If set, will add an unselectable header with given text and <see cref="Icon"/>.
	/// </summary>
	public string Title
	{
		get => TitleLabel?.Text;
		set
		{
			CreateHeader();
			TitleLabel.Text = value;
		}
	}

	/// <summary>
	/// If set, will add an unselectable header with given icon and <see cref="Title"/>.
	/// </summary>
	public string Icon
	{
		get => IconPanel?.Text;
		set
		{
			CreateHeader();
			IconPanel.Text = value;
		}
	}

	/// <summary>
	/// Closes all panels, marks this one as a success and closes it.
	/// </summary>
	public void Success()
	{
		AddClass( "success" );
		Popup.CloseAll();
	}

	/// <summary>
	/// Closes all panels, marks this one as a failure and closes it.
	/// </summary>
	public void Failure()
	{
		AddClass( "failure" );
		Popup.CloseAll();
	}

	/// <summary>
	/// Add an option to this popup with given text and click action.
	/// </summary>
	public Panel AddOption( string text, Action action = null )
	{
		return AddChild( new Button( text, () =>
		{
			action?.Invoke();
		} ) );
	}

	/// <summary>
	/// Add an option to this popup with given text, icon and click action.
	/// </summary>
	public Panel AddOption( string text, string icon, Action action = null )
	{
		return AddChild( new Button( text, icon, () => { action?.Invoke(); } ) );
	}

	/// <summary>
	/// Move selection in given direction.
	/// </summary>
	/// <param name="dir">Positive numbers move selection downwards, negative - upwards.</param>
	public void MoveSelection( int dir )
	{
		var currentIndex = GetChildIndex( SelectedChild );

		if ( currentIndex >= 0 ) currentIndex += dir;
		else if ( currentIndex < 0 ) currentIndex = dir == 1 ? 0 : -1;

		SelectedChild?.SetClass( "active", false );
		SelectedChild = GetChild( currentIndex, true );
		SelectedChild?.SetClass( "active", true );
	}

	public void MouseDown()
	{
	}

	public override void Tick()
	{
		base.Tick();
		if ( !PopupSource.IsValid() )
		{
			Delete( true );
			return;
		}
		if ( !(HasFocus || PopupSource.HasFocus) )
		{
			if ( PopupSource is ComboBox dp )
			{
				dp.Close();
			}
		}
		PositionMe();
	}

	float _initialMouseX = -1;
	float _initialMouseY = -1;

	void PositionMe()
	{
		//copy stylesheet from source panel
		UpdateStyle();
		Parent = FindRootPanel();

		var rect = PopupSource.Box.Rect;

		var w = Parent.Box.Rect.Width * PopupSource.ScaleFromScreen;
		var h = Parent.Box.Rect.Height * PopupSource.ScaleFromScreen;


		Style.MaxHeight = Screen.Height - 50;



		switch ( Position )
		{
			case PositionMode.Left:
				Style.Left = ((rect.Left - Parent.Box.Left - 1)) * PopupSource.ScaleFromScreen;
				Style.Top = ((rect.Top - Parent.Box.Top - 1) + PopupSourceOffset) * PopupSource.ScaleFromScreen;
				break;

			case PositionMode.LeftBottom:
				Style.Left = ((rect.Left - Parent.Box.Left - 1)) * PopupSource.ScaleFromScreen;
				Style.Top = ((rect.Bottom - Parent.Box.Top - 1) + PopupSourceOffset) * PopupSource.ScaleFromScreen;
				break;
			case PositionMode.Right:
				Style.Left = ((rect.Right - Parent.Box.Left - 1)) * PopupSource.ScaleFromScreen;
				Style.Top = ((rect.Top - Parent.Box.Top - 1) + PopupSourceOffset) * PopupSource.ScaleFromScreen;
				break;
			case PositionMode.RightBottom:
				Style.Left = ((rect.Right - Parent.Box.Left - 1)) * PopupSource.ScaleFromScreen;
				Style.Top = ((rect.Bottom - Parent.Box.Top - 1) + PopupSourceOffset) * PopupSource.ScaleFromScreen;
				break;

			case PositionMode.AboveLeft:
				Style.Left = ((rect.Left - Parent.Box.Left - 1)) * PopupSource.ScaleFromScreen;
				Style.Top = ((rect.Top - Parent.Box.Top - 1) + PopupSourceOffset) * PopupSource.ScaleFromScreen;
				break;

			case PositionMode.BelowLeft:
				Style.Left = ((rect.Left - Parent.Box.Left - 1)) * PopupSource.ScaleFromScreen;
				Style.Top = ((rect.Bottom - Parent.Box.Top - 1) + PopupSourceOffset) * PopupSource.ScaleFromScreen;
				break;

			case PositionMode.BelowCenter:
				Style.Left = ((rect.Left - Parent.Box.Left - 1) + rect.Width * 0.5f) * PopupSource.ScaleFromScreen;
				Style.Top = ((rect.Bottom - Parent.Box.Top - 1) + PopupSourceOffset) * PopupSource.ScaleFromScreen;
				break;

			case PositionMode.BelowStretch:
				Style.Left = ((rect.Left - Parent.Box.Left - 1)) * PopupSource.ScaleFromScreen;
				Style.Top = ((rect.Bottom - Parent.Box.Top - 1) + PopupSourceOffset) * PopupSource.ScaleFromScreen;
				Style.Width = rect.Width;
				break;

			case PositionMode.UnderMouse:
				if ( _initialMouseX == -1 || _initialMouseY == -1 )
				{
					_initialMouseX = Mouse.Position.x;
					_initialMouseY = Mouse.Position.y;
				}
				Style.Left = ((_initialMouseX - Parent.Box.Left - 1)) * PopupSource.ScaleFromScreen;
				Style.Top = ((_initialMouseY - Parent.Box.Top - 1) + PopupSourceOffset) * PopupSource.ScaleFromScreen;
				break;
		}


		Style.Dirty();
	}

}