using Godot;

namespace Movementtests.systems;

public record DashComputation(bool HasHit, Vector3 Location, Vector3 CollisionPoint, Vector3 CollisionNormal);

public record DashResolve(bool EndWithMantle, Vector3 DashLocation, Vector3 MantleLocation);

public partial class DashSystem: Node3D
{
    [Export(PropertyHint.Range, "0,0.2,0.01,or_greater")]
    public float DashSpeed { get; set; } = 0.05f;
    
    private Node3D _head;
    private ShapeCast3D _dashCast3D;
    private Camera3D _camera;
    private TweenQueueSystem _tweenQueueSystem;

    private MantleSystem _mantleSystem;
    private MeshInstance3D _dashTarget;
    
    private DashResolve _dashResolve;

    [Signal]
    public delegate void DashStartedEventHandler();
    [Signal]
    public delegate void DashEndedEventHandler();

    public void Init(Node3D head, Camera3D camera, TweenQueueSystem tweenQueueSystem)
    {
        _dashCast3D = GetNode<ShapeCast3D>("DashCast3D");
        _head = head;
        _camera = camera;
        _tweenQueueSystem = tweenQueueSystem;
        
        _mantleSystem = GetNode<MantleSystem>("MantleSystem");
        _mantleSystem.Init(this);
        
        _dashTarget = GetNode<MeshInstance3D>("DashTarget");
        _dashTarget.SetVisible(false);
    }

    private DashComputation ComputeDashLocation()
    {
        if (!_dashCast3D.IsColliding())
        {
            return new DashComputation(false, _dashCast3D.ToGlobal(_dashCast3D.TargetPosition), Vector3.Zero, Vector3.Zero);
        }
        var collisionPoint = _dashCast3D.GetCollisionPoint(0);
        var collisionNormal = _dashCast3D.GetCollisionNormal(0);
        var collisionShape = (SphereShape3D) _dashCast3D.GetShape();
        var centerSphereLocation = collisionPoint + collisionNormal * collisionShape.Radius;
        return new DashComputation(true, centerSphereLocation, collisionPoint, collisionNormal);
    }

    public DashResolve PrepareDash()
    {
        _dashTarget.SetVisible(false);
        
        _dashCast3D.SetRotation(new Vector3(
            _camera.Rotation.X,
            _head.Rotation.Y,
            _camera.Rotation.Z));

        var (hasHit, location, collisionPoint, collisionNormal) = ComputeDashLocation();

        var shouldMantle = false;
        var mantleLocation = Vector3.Zero;
        if (hasHit && Mathf.Abs(collisionNormal.Y) < 0.01f)
        {
            var mantleResult = _mantleSystem.FindMantleLocationAtPoint(collisionPoint, collisionNormal);
            shouldMantle = mantleResult.IsSome(out mantleLocation);
        }
        
        var targetColor = shouldMantle ? new Color(0.2f, 0.2f, 1f) : new Color(1f, 1f, 1f);
        var targetMaterial = (StandardMaterial3D) _dashTarget.GetSurfaceOverrideMaterial(0);
        targetMaterial.SetAlbedo(targetColor);
        _dashTarget.SetVisible(true);
        _dashTarget.SetGlobalPosition(location);
        
        _dashResolve = new DashResolve(shouldMantle, location, mantleLocation);
        return _dashResolve;
    }

    public void CancelDash()
    {
        _dashTarget.SetVisible(false);
    }

    public void DashTweenEnded()
    {
        EmitSignal(SignalName.DashEnded);
    }

    public void Dash()
    {
        EmitSignal(SignalName.DashStarted);
        _dashTarget.SetVisible(false);
        var dashTweenInputs = new TweenQueueSystem.TweenInputs(_dashResolve.DashLocation, 0.1f);
        var dashTween = _tweenQueueSystem.TweenToLocation(dashTweenInputs);
        dashTween.Finished += DashTweenEnded;
        if (_dashResolve.EndWithMantle)
        {
            _tweenQueueSystem.QueueTween(_dashResolve.MantleLocation, 0.2f);
        }
    }
}