using System;
using System.Collections;
using System.Linq;
using UnityEngine;
using UnityEngine.UI;
using ZXing;

public class QRCode : MonoBehaviour
{
    public RawImage rawImage;
    private WebCamTexture webCamTexture;
    private Color32[] data;
    private BarcodeReader barcodeReader;
    public Text text;
    private int width;
    private int height;
    private int lastRotationAngle;
    private RectTransform rectTransform;

    private IEnumerator Start()
    {
        width = Screen.width;
        height = Screen.height;
        rectTransform = GetComponent<RectTransform>();
        barcodeReader = new BarcodeReader();
        yield return Application.RequestUserAuthorization(UserAuthorization.WebCam);
        if (Application.HasUserAuthorization(UserAuthorization.WebCam))
        {
            var device = WebCamTexture.devices.FirstOrDefault(o => !o.isFrontFacing);
            webCamTexture = new WebCamTexture(device.name, width, height, 25);
            data = new Color32[webCamTexture.width * webCamTexture.height];
            rawImage.texture = webCamTexture;
            webCamTexture.Play();
            //InvokeRepeating(nameof(CheckQRCode), 0, 1f);
        }
    }

    private IEnumerator CheckQRCode()
    {
        yield return null;
        if (webCamTexture != null && webCamTexture.isPlaying)
        {
            data = webCamTexture.GetPixels32();
            if (data != null)
            {
                try
                {
                    var tResult = barcodeReader.Decode(data, webCamTexture.width, webCamTexture.height);
                    if (tResult != null)
                    {
                        text.text = tResult.Text; //$"{tResult.BarcodeFormat}:{tResult.Text}";
                    }
                }
                catch (Exception ex)
                {
                    Debug.LogError(ex.Message);
                }
            }
        }
    }

    private void OnEnable()
    {
        if (Application.HasUserAuthorization(UserAuthorization.WebCam) && webCamTexture != null)
        {
            webCamTexture.Play();
        }
    }

    private void OnDisable()
    {
        if (Application.HasUserAuthorization(UserAuthorization.WebCam) && webCamTexture != null)
        {
            webCamTexture.Stop();
        }
    }

    private void Update()
    {
        if (webCamTexture != null && lastRotationAngle != webCamTexture.videoRotationAngle)
        {
            OnOrientationChanged();
            lastRotationAngle = webCamTexture.videoRotationAngle;
        }
        StartCoroutine(CheckQRCode());
    }

    private void OnOrientationChanged()
    {
        transform.localRotation = Quaternion.Euler(0, 0, -webCamTexture.videoRotationAngle);

        //if (webCamTexture.videoRotationAngle % 180 != 0)
        //{
        //    rectTransform.sizeDelta = new Vector2(height, width);
        //}
        //else
        //{
        //    rectTransform.sizeDelta = new Vector2(width, height);
        //}
    }

    private void OnGUI()
    {
        GUILayout.Label(webCamTexture.videoRotationAngle.ToString());
        GUILayout.Label(webCamTexture.videoVerticallyMirrored.ToString());
    }
}