using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.InputSystem;
using UnityEngine.XR;

namespace Fusion.XR.Host.Utils
{
    /*
     * Workaround the OpenXR 1.9.1 bug regarding the floor tracking origine, see https://forum.unity.com/threads/update-com-unity-xr-openxr-from-1-8-2-to-1-9-1-changes-tracking-origin.1515263/
     */
    public class ResetTrackingOrigin : MonoBehaviour
    {
        public float fixDuration = 3;
        float fixElapsedTime = 0;

        public List<string> unityVersionRequiringFixing = new List<string> { "2021.3.32f1" };
        public InputActionProperty headsetAvailableAction = new InputActionProperty();

        public enum Status
        {
            Unknown,
            FixNotRequired,
            FixRequiredHeadsetNotDetected,
            FixBeingApplied,
            FixFinished
        }
        public Status status = Status.Unknown;

        public bool HeadsetDetected
        {
            get
            {
                InputTrackingState trackingState = (InputTrackingState)headsetAvailableAction.action.ReadValue<int>();
                return trackingState != InputTrackingState.None;
            }
        }

        private void Awake()
        {
            headsetAvailableAction.EnableWithDefaultXRBindings(new List<string> { "<XRHMD>/trackingState" });
        }

        private void Start()
        {
            if (unityVersionRequiringFixing.Contains(Application.unityVersion))
            {
                Debug.LogError($"[ResetTrackingOrigin] The <a href=\"https://forum.unity.com/threads/update-com-unity-xr-openxr-from-1-8-2-to-1-9-1-changes-tracking-origin.1515263/\">OpenXR 1.9.1 floor tracking issue</a> fix is required for this version of Unity ({Application.unityVersion}). The XR Rig TrackingOriginMode will be tweak for {(int)fixDuration} seconds.");
                Debug.Log("Looking for headset...");
                status = Status.FixRequiredHeadsetNotDetected;
            }
            else
            {
                Debug.LogWarning($"[ResetTrackingOrigin] The <a href=\"https://forum.unity.com/threads/update-com-unity-xr-openxr-from-1-8-2-to-1-9-1-changes-tracking-origin.1515263/\">OpenXR 1.9.1 floor tracking issue</a> fix is not know to be required for this version of Unity ({Application.unityVersion}). If you're camera appears in the floot, add this version of Unity to ResetTrackingOrigin unityVersionRequiringFixing list of version to fix.");
                status = Status.FixNotRequired;
            }
        }

        private void Update()
        {
            if (status == Status.FixRequiredHeadsetNotDetected && HeadsetDetected)
            {
                Debug.Log("Floor tracking origin fix start");
                status = Status.FixBeingApplied;
            }
            if (status != Status.FixBeingApplied) return;
            if (fixElapsedTime >= fixDuration)
            {
                fixElapsedTime = -1;
                Debug.Log("Floor tracking origin fix stop");
                status = Status.FixFinished;
            }
            else
            {
                FixfloorOrigin();
                fixElapsedTime += Time.deltaTime;
            }
        }
        private void FixfloorOrigin()
        {
            List<XRInputSubsystem> inputSubsystems = new List<XRInputSubsystem>();
            SubsystemManager.GetSubsystems<XRInputSubsystem>(inputSubsystems);
            foreach (var inputSubsystem in inputSubsystems)
            {
                // change the tracking oroigin to set it to floor
                if (inputSubsystem.TrySetTrackingOriginMode(TrackingOriginModeFlags.Device)) { }
                if (inputSubsystem.TrySetTrackingOriginMode(TrackingOriginModeFlags.Floor)) { }
            }
        }
    }

}