using Sandbox;
using Sandbox.UI;
using System;
using System.Threading.Tasks;

/// <summary>
/// Attach to each cell prefab GameObject alongside a WorldPanel + CellPanel (PanelComponent).
/// GridRenderer calls SetBomb / SetChest / SetEmpty to update display state.
/// Float text uses the Camera.Hud draw API — no WorldPanel spawning needed.
/// </summary>
public sealed class GridCellPanel : Component
{
	// ── Inspector ─────────────────────────────────────────────────────────
	/// Wire to the PanelComponent (CellPanel.razor) on this same GameObject
	[Property] public PanelComponent CellUI { get; set; }

	// ── Click callback (set by GridRenderer) ──────────────────────────────
	public Action OnClicked;

	// ── Display state (read by CellPanel.razor) ───────────────────────────
	public string Icon { get; private set; } = "";
	public string Label { get; private set; } = "";
	public int HitsLeft { get; private set; }
	public bool IsBomb { get; private set; }
	public bool IsChest { get; private set; }
	public bool Danger { get; private set; }

	// ── Float text queue (drawn each frame via OnUpdate) ──────────────────
	record FloatEntry( string Text, Color Col, float SpawnTime, float Duration );
	readonly System.Collections.Generic.List<FloatEntry> _floats = new();

	// ── API ───────────────────────────────────────────────────────────────
	public void SetEmpty()
	{
		Icon = ""; Label = ""; IsBomb = false; IsChest = false; Danger = false;
		Refresh();
	}

	public void SetBomb( string icon, string label )
	{
		Icon = icon; Label = label; IsBomb = true; IsChest = false;
		Refresh();
	}

	public void SetChest( string icon, int hitsLeft, bool danger )
	{
		Icon = icon; HitsLeft = hitsLeft; IsBomb = false; IsChest = true; Danger = danger;
		Refresh();
	}

	// ── Animations ────────────────────────────────────────────────────────
	public async Task AnimateFire()
	{
		await ScaleTo( 1.45f, 0.07f );
		await ScaleTo( 0.75f, 0.07f );
		await ScaleTo( 1.15f, 0.07f );
		await ScaleTo( 1.00f, 0.07f );
	}

	public async Task AnimateBurst( int coins, float mult )
	{
		await AnimateFire();

		Color col = mult >= 3f ? new Color( 0.50f, 0.47f, 0.87f )   // #7F77DD
				  : mult >= 2f ? new Color( 0.11f, 0.62f, 0.46f )   // #1D9E75
				  : new Color( 0.72f, 0.53f, 0.04f );   // #B8860B

		QueueFloat( $"+{coins}🪙", col, 0.9f );

		if ( mult >= 2f )
		{
			string label = mult >= 4f ? "×4 CHAIN REACTION! 💥"
						 : mult >= 3f ? "×3 ON FIRE! 🔥"
						 : "×2 CHAIN!";
			QueueFloat( label, new Color( 0.33f, 0.29f, 0.72f ), 1.3f );
		}
	}

	void QueueFloat( string text, Color col, float duration )
	{
		_floats.Add( new FloatEntry( text, col, Time.Now, duration ) );
	}

	// ── Draw floating text via Hud each frame ─────────────────────────────
	protected override void OnUpdate()
	{
		if ( _floats.Count == 0 ) return;
		var cam = Scene.Camera;
		if ( cam is null ) return;

		_floats.RemoveAll( f => Time.Now - f.SpawnTime >= f.Duration );

		foreach ( var f in _floats )
		{
			float t = (Time.Now - f.SpawnTime) / f.Duration;
			float alpha = 1f - t;
			var worldPos = WorldPosition + Vector3.Up * (40f + t * 60f);

			// Cull if behind camera
			var camFwd = cam.WorldRotation.Forward;
			if ( Vector3.Dot( camFwd, (worldPos - cam.WorldPosition).Normal ) < 0.1f )
				continue;

			var screenPos = cam.PointToScreenPixels( worldPos );

			cam.Hud.DrawText(
				new TextRendering.Scope(
					f.Text,
					f.Col.WithAlpha( alpha ),
					20,
					weight: 700
				),
				screenPos
			);
		}
	}

	// ── Scale tween ───────────────────────────────────────────────────────
	async Task ScaleTo( float target, float duration )
	{
		float elapsed = 0f;
		float start = GameObject.LocalScale.x;

		while ( elapsed < duration )
		{
			elapsed += Time.Delta;
			float t = MathF.Min( elapsed / duration, 1f );
			float s = start + (target - start) * t;
			GameObject.LocalScale = new Vector3( s, s, s );
			await Task.Yield();
		}

		GameObject.LocalScale = new Vector3( target, target, target );
	}

	// ── Refresh ───────────────────────────────────────────────────────────
	void Refresh() => CellUI?.StateHasChanged();

	// ── Init ──────────────────────────────────────────────────────────────
	protected override void OnStart()
	{
		if ( CellUI?.Panel is not null )
			CellUI.Panel.AddEventListener( "onclick", _ => OnClicked?.Invoke() );
	}
}