using System;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.Serialization;

namespace Shared
{
    public class PlaceAnchorScript : MonoBehaviour
    {
        [SerializeField] private GameObject saveableAnchorPrefab;

        [SerializeField] private GameObject saveablePreview;

        [SerializeField] private Transform saveableTransform;

        [SerializeField] private GameObject nonSaveableAnchorPrefab;

        [SerializeField] private GameObject nonSaveablePreview;

        [SerializeField] private Transform nonSaveableTransform;

        private List<OVRSpatialAnchor> _anchorInstances = new(); // Active instances (red and green)

        private HashSet<Guid> _anchorUuids = new(); // Simulated external location, like PlayerPrefs

        private Action<bool, OVRSpatialAnchor.UnboundAnchor> _onLocalized;

        // public GameObject anchorPrefab;
        // private ulong _requestedId;

        // private void Awake()
        // {
        //     if (Instance == null)
        //     {
        //         Instance = this;
        //         _onLocalized = OnLocalized;
        //     }
        //     else
        //     {
        //         Destroy(this);
        //     }
        // }

        // Update is called once per frame
        private void Update()
        {
            // if (OVRInput.GetDown(OVRInput.Button.PrimaryIndexTrigger, OVRInput.Controller.RTouch))
            // {
            // }
            CreateSpatialAnchors();

            // Destroy displayed anchors
            if (OVRInput.GetDown(OVRInput.Button.Three)) // x button
            {
                // Destroy all anchors from the scene, but don't erase them from storage
                foreach (var anchor in _anchorInstances)
                {
                    Destroy(anchor.gameObject);
                }

                // Clear the list of running anchors
                _anchorInstances.Clear();
            }

            // load anchors
            if (OVRInput.GetDown(OVRInput.Button.One)) // a button
            {
                LoadAllAnchors(); // Load saved anchors
            }

            // Erase all saved (green) anchors
            if (OVRInput.GetDown(OVRInput.Button.Four)) // y button
            {
                EraseAllAnchors();
            }
        }

        private void CreateSpatialAnchors()
        {
            if (OVRInput.GetDown(OVRInput.Button.PrimaryIndexTrigger)) // Create a green capsule
            {
                // Create a green (savable) spatial anchor
                var go = Instantiate(saveableAnchorPrefab, saveableTransform.position,
                    saveableTransform.rotation); // Anchor A
                SetupAnchorAsync(go.AddComponent<OVRSpatialAnchor>(), saveAnchor: true);
            }
            else if (OVRInput.GetDown(OVRInput.Button.SecondaryIndexTrigger)) // Create a red capsule
            {
                // Create a red (non-savable) spatial anchor.
                var go = Instantiate(nonSaveableAnchorPrefab, nonSaveableTransform.position,
                    nonSaveableTransform.rotation); // Anchor b
                SetupAnchorAsync(go.AddComponent<OVRSpatialAnchor>(), saveAnchor: false);
            }
        }

        private async void SetupAnchorAsync(OVRSpatialAnchor anchor, bool saveAnchor)
        {
            // Keep checking for a valid and localized anchor state
            if (!await anchor.WhenLocalizedAsync())
            {
                Debug.LogError($"Unable to create anchor.");
                Destroy(anchor.gameObject);
                return;
            }

            // Add the anchor to the list of all instances
            _anchorInstances.Add(anchor);

            // save the savable (green) anchors only
            if (saveAnchor && (await anchor.SaveAnchorAsync()).Success)
            {
                // Remember UUID so you can load the anchor later
                _anchorUuids.Add(anchor.Uuid);
            }
        }

        public async void LoadAllAnchors()
        {
            // Load and localize
            var unboundAnchors = new List<OVRSpatialAnchor.UnboundAnchor>();
            var result = await OVRSpatialAnchor.LoadUnboundAnchorsAsync(_anchorUuids, unboundAnchors);

            if (result.Success)
            {
                foreach (var anchor in unboundAnchors)
                {
                    anchor.LocalizeAsync().ContinueWith(_onLocalized, anchor);
                }
            }
            else
            {
                Debug.LogError($"Load anchors failed with {result.Status}.");
            }
        }

        private void OnLocalized(bool success, OVRSpatialAnchor.UnboundAnchor unboundAnchor)
        {
            var pose = unboundAnchor.Pose;
            var go = Instantiate(saveableAnchorPrefab, pose.position, pose.rotation);
            var anchor = go.AddComponent<OVRSpatialAnchor>();

            unboundAnchor.BindTo(anchor);

            // Add the anchor to the running total
            _anchorInstances.Add(anchor);
        }

        public async void EraseAllAnchors()
        {
            var result = await OVRSpatialAnchor.EraseAnchorsAsync(anchors: null, uuids: _anchorUuids);
            if (result.Success)
            {
                // Erase our reference lists
                _anchorUuids.Clear();

                Debug.Log($"Anchors erased.");
            }
            else
            {
                Debug.LogError($"Anchors NOT erased {result.Status}");
            }
        }

        // private void CreateSpatialAnchor()
        // {
        //     var prefab = Instantiate(anchorPrefab, OVRInput.GetLocalControllerPosition(OVRInput.Controller.RTouch),
        //         OVRInput.GetLocalControllerRotation(OVRInput.Controller.RTouch));
        //     prefab.AddComponent<OVRSpatialAnchor>();
        // }

        // private OVRPose GetTrackingSpacePose()
        // {
        //     var mainCamera = Camera.main;
        //
        //     if (mainCamera) return transform.ToTrackingSpacePose(mainCamera);
        //
        //
        //     Debug.LogError("Main camera not found. Using world-space pose.");
        //     return transform.ToOVRPose(isLocal: false);
        // }
        //
        // private void CreateSpatialAnchor()
        // {
        //     var created = OVRPlugin.CreateSpatialAnchor(new OVRPlugin.SpatialAnchorCreateInfo
        //     {
        //         BaseTracking = OVRPlugin.GetTrackingOriginType(),
        //         PoseInSpace = GetTrackingSpacePose().ToPosef(),
        //         Time = OVRPlugin.GetTimeInSeconds()
        //     }, out _requestedId);
        //
        //     if (created)
        //     {
        //         Debug.Log($"Spatial anchor created with ID: {_requestedId}");
        //         // CreationRequests[_requestedId] = this;
        //     }
        //     else
        //     {
        //         Debug.LogError($"Failed to create spatial anchor with ID: {_requestedId}");
        //         Destroy(this);
        //     }
        // }
    }
}