using UnityEngine;
using UnityEngine.SceneManagement;
using System.Collections;
using OpenCVForUnity.CoreModule;
using OpenCVForUnity.VideoModule;
using OpenCVForUnity.ImgprocModule;
using OpenCVForUnity.UnityUtils;
using OpenCVForUnity.UnityUtils.Helper;

namespace OpenCVForUnityExample
{
    /// <summary>
    /// BackgroundSubtractorMOG2 Example
    /// An example of background subtraction using the Video.BackgroundSubtractorMOG2 class.
    /// Referring to http://docs.opencv.org/master/d1/dc5/tutorial_background_subtraction.html#gsc.tab=0.
    /// </summary>
    [RequireComponent (typeof(WebCamTextureToMatHelper))]
    public class BackgroundSubtractorMOG2Example : MonoBehaviour
    {
        /// <summary>
        /// The texture.
        /// </summary>
        Texture2D texture;

        /// <summary>
        /// The webcam texture to mat helper.
        /// </summary>
        WebCamTextureToMatHelper webCamTextureToMatHelper;

        /// <summary>
        /// The background substractor MOG2.
        /// </summary>
        BackgroundSubtractorMOG2 backgroundSubstractorMOG2;

        /// <summary>
        /// The rgb mat.
        /// </summary>
        Mat rgbMat;

        /// <summary>
        /// The fgmask mat.
        /// </summary>
        Mat fgmaskMat;

        /// <summary>
        /// The FPS monitor.
        /// </summary>
        FpsMonitor fpsMonitor;

        // Use this for initialization
        void Start ()
        {
            fpsMonitor = GetComponent<FpsMonitor> ();

            webCamTextureToMatHelper = gameObject.GetComponent<WebCamTextureToMatHelper> ();

            #if UNITY_ANDROID && !UNITY_EDITOR
            // Avoids the front camera low light issue that occurs in only some Android devices (e.g. Google Pixel, Pixel2).
            webCamTextureToMatHelper.avoidAndroidFrontCameraLowLightIssue = true;
            #endif
            webCamTextureToMatHelper.Initialize ();

            backgroundSubstractorMOG2 = Video.createBackgroundSubtractorMOG2 ();
//                      backgroundSubstractorMOG2.setHistory (2);
//                      backgroundSubstractorMOG2.setVarThreshold (16);
//                      backgroundSubstractorMOG2.setDetectShadows (true);

        }

        /// <summary>
        /// Raises the webcam texture to mat helper initialized event.
        /// </summary>
        public void OnWebCamTextureToMatHelperInitialized ()
        {
            Debug.Log ("OnWebCamTextureToMatHelperInitialized");

            Mat webCamTextureMat = webCamTextureToMatHelper.GetMat ();

            texture = new Texture2D (webCamTextureMat.cols (), webCamTextureMat.rows (), TextureFormat.RGBA32, false);

            gameObject.GetComponent<Renderer> ().material.mainTexture = texture;

            gameObject.transform.localScale = new Vector3 (webCamTextureMat.cols (), webCamTextureMat.rows (), 1);

            Debug.Log ("Screen.width " + Screen.width + " Screen.height " + Screen.height + " Screen.orientation " + Screen.orientation);

            if (fpsMonitor != null) {
                fpsMonitor.Add ("width", webCamTextureMat.width ().ToString ());
                fpsMonitor.Add ("height", webCamTextureMat.height ().ToString ());
                fpsMonitor.Add ("orientation", Screen.orientation.ToString ());
            }


            float width = webCamTextureMat.width ();
            float height = webCamTextureMat.height ();
                                    
            float widthScale = (float)Screen.width / width;
            float heightScale = (float)Screen.height / height;
            if (widthScale < heightScale) {
                Camera.main.orthographicSize = (width * (float)Screen.height / (float)Screen.width) / 2;
            } else {
                Camera.main.orthographicSize = height / 2;
            }

            rgbMat = new Mat (webCamTextureMat.rows (), webCamTextureMat.cols (), CvType.CV_8UC3);
            fgmaskMat = new Mat (webCamTextureMat.rows (), webCamTextureMat.cols (), CvType.CV_8UC1);
        }

        /// <summary>
        /// Raises the webcam texture to mat helper disposed event.
        /// </summary>
        public void OnWebCamTextureToMatHelperDisposed ()
        {
            Debug.Log ("OnWebCamTextureToMatHelperDisposed");
            if (rgbMat != null)
                rgbMat.Dispose ();

            if (fgmaskMat != null)
                fgmaskMat.Dispose ();

            if (texture != null) {
                Texture2D.Destroy (texture);
                texture = null;
            }
        }

        /// <summary>
        /// Raises the webcam texture to mat helper error occurred event.
        /// </summary>
        /// <param name="errorCode">Error code.</param>
        public void OnWebCamTextureToMatHelperErrorOccurred (WebCamTextureToMatHelper.ErrorCode errorCode)
        {
            Debug.Log ("OnWebCamTextureToMatHelperErrorOccurred " + errorCode);
        }

        // Update is called once per frame
        void Update ()
        {
            if (webCamTextureToMatHelper.IsPlaying () && webCamTextureToMatHelper.DidUpdateThisFrame ()) {

                Mat rgbaMat = webCamTextureToMatHelper.GetMat ();

                Imgproc.cvtColor (rgbaMat, rgbMat, Imgproc.COLOR_RGBA2RGB);
                backgroundSubstractorMOG2.apply (rgbMat, fgmaskMat);

                Core.bitwise_not (fgmaskMat, fgmaskMat);
                rgbaMat.setTo (new Scalar (0, 0, 0, 0), fgmaskMat);

                Utils.fastMatToTexture2D (rgbaMat, texture);
            }
        }

        /// <summary>
        /// Raises the destroy event.
        /// </summary>
        void OnDestroy ()
        {
            webCamTextureToMatHelper.Dispose ();
        }

        /// <summary>
        /// Raises the back button click event.
        /// </summary>
        public void OnBackButtonClick ()
        {
            SceneManager.LoadScene ("OpenCVForUnityExample");
        }

        /// <summary>
        /// Raises the play button click event.
        /// </summary>
        public void OnPlayButtonClick ()
        {
            webCamTextureToMatHelper.Play ();
        }

        /// <summary>
        /// Raises the pause button click event.
        /// </summary>
        public void OnPauseButtonClick ()
        {
            webCamTextureToMatHelper.Pause ();
        }

        /// <summary>
        /// Raises the stop button click event.
        /// </summary>
        public void OnStopButtonClick ()
        {
            webCamTextureToMatHelper.Stop ();
        }

        /// <summary>
        /// Raises the change camera button click event.
        /// </summary>
        public void OnChangeCameraButtonClick ()
        {
            webCamTextureToMatHelper.requestedIsFrontFacing = !webCamTextureToMatHelper.IsFrontFacing ();
        }
    }
}