import UIKit
import SceneKit
import ARKit

class ViewController: UIViewController, ARSCNViewDelegate {

    @IBOutlet var sceneView: ARSCNView!
    
    @IBOutlet weak var switchDraw: UISwitch!
    override func viewDidLoad() {
        super.viewDidLoad()
        
        // Set the view's delegate
        sceneView.delegate = self
        
        // Show statistics such as fps and timing information
        sceneView.showsStatistics = true
        //sceneView.debugOptions = [ARSCNDebugOptions.showFeaturePoints, .showWorldOrigin]
        

    }
    
    func renderer(_ renderer: SCNSceneRenderer, willRenderScene scene: SCNScene, atTime time: TimeInterval) {
        
        
        guard let pov = sceneView.pointOfView else {
            return
        }
        let transform = pov.transform
        let rotation = SCNVector3(-transform.m31, -transform.m32, -transform.m33)
        let location = SCNVector3(transform.m41, transform.m42, transform.m43)
        let currentPosition = SCNVector3(rotation.x + location.x, rotation.y + location.y, rotation.z + location.z)
        
        DispatchQueue.main.async {
            if self.switchDraw.isOn {
                let drawNode = SCNNode()
                drawNode.geometry = SCNSphere(radius: 0.01)
                drawNode.geometry?.firstMaterial?.diffuse.contents = UIColor.green
                drawNode.position = currentPosition
                self.sceneView.scene.rootNode.addChildNode(drawNode)
            } else {
                let point = SCNNode()
                point.name = "çizim noktası"
                point.geometry = SCNSphere(radius: 0.005)
                point.position = currentPosition
                point.geometry?.firstMaterial?.diffuse.contents = UIColor.red
                
                self.sceneView.scene.rootNode.enumerateChildNodes( {(node, _) in
                    if node.name == "çizim noktası" {
                        node.removeFromParentNode()
                    }
                })
                self.sceneView.scene.rootNode.addChildNode(point)
            }
        }
        
    }
    
    override func viewWillAppear(_ animated: Bool) {
        super.viewWillAppear(animated)
        
        // Create a session configuration
        let configuration = ARWorldTrackingConfiguration()

        // Run the view's session
        sceneView.session.run(configuration)
    }
    
    override func viewWillDisappear(_ animated: Bool) {
        super.viewWillDisappear(animated)
        
        // Pause the view's session
        sceneView.session.pause()
    }


}