using System;
using System.Collections;
using EZXR.Glass.SixDof;
using System.Runtime.InteropServices;
using UnityEngine;
using Wheels.Unity;
using EZXR.Glass.Device;
using EZXR.Glass.Core;

namespace EZXR.Glass.QRScanner
{
    public class ScannerHandler : MonoBehaviour
    {
        public GameObject scanningView;
        public GameObject successView;
        public GameObject failedView;

        private byte[] imageBuffer;
        private int[] imageBufferClamp;
        private NormalRGBCameraDevice rgbCameraDevice;
        private EZVIOInputImage camImageBuffer;

        private Action startListeners;
        private Action<bool, string> completeListeners;
        private ZXing.BarcodeReader barcodeReader;

        private bool isCameraOpen = false;
        private bool isScannerStarted = false;
        private bool isScannnerComplete = false;

        private string qrCodeContent;

        private Coroutine timerCoroutine;

        private void Awake()
        {
            // ZeroDof
            transform.ActAsChild(HMDPoseTracker.Instance.Head);
        }

        private void OnEnable()
        {
            scanningView.SetActive(true);
            successView.SetActive(false);
            failedView.SetActive(false);

            qrCodeContent = string.Empty;
            StartCoroutine(startRGBCamera());

            timerCoroutine = StartCoroutine(startScannerTimer());
        }

        private void OnDisable()
        {
            Debug.Log($"-- ScannerHandler --, Scannner Complete: {qrCodeContent}");
            var isScanned = !string.IsNullOrEmpty(qrCodeContent);
            completeListeners?.Invoke(isScanned, qrCodeContent);

            if (timerCoroutine != null)
            {
                StopCoroutine(timerCoroutine);
                timerCoroutine = null;
            }

            stopRGBCamera();
            isScannerStarted = false;
            isScannnerComplete = false;
        }

        private void Update()
        {
            if (!isScannnerComplete && UpdateRGBCamera())
            {
                if (!isScannerStarted)
                {
                    isScannerStarted = true;
                    startListeners?.Invoke();
                }

                if (DecodeYUVImage(out var something))
                {
                    isScannnerComplete = true;
                    qrCodeContent = something;
                    StartCoroutine(DelayAndDisable(1f));

                    scanningView.SetActive(false);
                    successView.SetActive(true);
                    gameObject.GetComponent<AudioSource>().Play();

                    if (timerCoroutine != null)
                    {
                        StopCoroutine(timerCoroutine);
                        timerCoroutine = null;
                    }
                }
            }
        }

        private IEnumerator startRGBCamera()
        {
            yield return new WaitUntil(() => SessionManager.Instance != null && SessionManager.Instance.IsInited);
            Debug.Log("-- ScannerHandler --, startRGBCamera");
            camImageBuffer = new EZVIOInputImage();
            rgbCameraDevice = new NormalRGBCameraDevice();
            rgbCameraDevice.Open();

            isCameraOpen = true;
        }

        private void stopRGBCamera()
        {
            Debug.Log("-- ScannerHandler --, stopRGBCamera");
            rgbCameraDevice?.Close();
            isCameraOpen = false;

            if (camImageBuffer.fullImg != IntPtr.Zero)
            {
                Marshal.FreeHGlobal(camImageBuffer.fullImg);
                camImageBuffer.fullImg = IntPtr.Zero;
            }

            if (imageBuffer != null)
                imageBuffer = null;
            if (imageBufferClamp != null)
                imageBufferClamp = null;
        }

        public void SetupListeners(Action onStart, Action<bool, string> onComplete)
        {
            startListeners = onStart;
            completeListeners = onComplete;
        }

        private bool UpdateRGBCamera()
        {
            if (ARFrame.SessionStatus != EZVIOState.EZVIOCameraState_Tracking)
                return false;
            if (!isCameraOpen || rgbCameraDevice == null)
                return false;

            return rgbCameraDevice.getCurrentImage(ref camImageBuffer, new float[8]);
        }

        private bool DecodeYUVImage(out string something)
        {
            something = string.Empty;

            if (camImageBuffer.imgFormat != EZVIOImageFormat.EZVIOImageFormat_YUV420A)
            {
                Debug.LogError($"-- ScannerHandler --, incompatible image format({camImageBuffer.imgFormat}) when decode.");
                return false;
            }

            int width = (int)camImageBuffer.imgRes.width;
            int height = (int)camImageBuffer.imgRes.height;

            int channelSize = width * height/* * 3 / 2*/;
            if (imageBuffer == null) imageBuffer = new byte[channelSize];
            Marshal.Copy(camImageBuffer.fullImg, imageBuffer, 0, channelSize);  //只读Y通道

            // create a reader with a custom luminance source
            if (barcodeReader == null) barcodeReader = new ZXing.BarcodeReader { AutoRotate = false, Options = new ZXing.Common.DecodingOptions { TryHarder = false } };
            var result = barcodeReader.Decode(new ZXing.PlanarYUVLuminanceSource(imageBuffer, width, height, 0, 0, width, height, false));

            if (result != null && !string.IsNullOrEmpty(result.Text))
            {
                something = result.Text;
                return true;
            }

            return false;
        }

        private IEnumerator startScannerTimer()
        {
            yield return new WaitForSeconds(60f);
            scanningView.SetActive(false);
            failedView.SetActive(true);
            isScannnerComplete = true;

            yield return DelayAndDisable(1f);
        }

        private IEnumerator DelayAndDisable(float delay)
        {
            yield return new WaitForSeconds(delay);
            gameObject.SetActive(false);
        }
    }
}