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

namespace OpenCVForUnityExample
{
    /// <summary>
    /// Face Detection WebCamTexture Example
    /// An example of detecting human face in a image of WebCamTexture using the CascadeClassifier class.
    /// http://docs.opencv.org/3.2.0/db/d28/tutorial_cascade_classifier.html
    /// </summary>
    [RequireComponent (typeof(WebCamTextureToMatHelper))]
    public class FaceDetectionWebCamTextureExample : MonoBehaviour
    {
        /// <summary>
        /// The gray mat.
        /// </summary>
        Mat grayMat;

        /// <summary>
        /// The texture.
        /// </summary>
        Texture2D texture;

        /// <summary>
        /// The cascade.
        /// </summary>
        CascadeClassifier cascade;

        /// <summary>
        /// The faces.
        /// </summary>
        MatOfRect faces;

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

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

        #if UNITY_WEBGL && !UNITY_EDITOR
        IEnumerator getFilePath_Coroutine;
        #endif

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

            webCamTextureToMatHelper = gameObject.GetComponent<WebCamTextureToMatHelper> ();

            #if UNITY_WEBGL && !UNITY_EDITOR
            getFilePath_Coroutine = Utils.getFilePathAsync ("lbpcascade_frontalface.xml", (result) => {
                getFilePath_Coroutine = null;

                cascade = new CascadeClassifier ();
                cascade.load (result);
                if (cascade.empty ()) {
                    Debug.LogError ("cascade file is not loaded. Please copy from “OpenCVForUnity/StreamingAssets/” to “Assets/StreamingAssets/” folder. ");
                }

                webCamTextureToMatHelper.Initialize ();
            });
            StartCoroutine (getFilePath_Coroutine);
            #else
            cascade = new CascadeClassifier ();
            cascade.load (Utils.getFilePath ("lbpcascade_frontalface.xml"));
//            cascade.load (Utils.getFilePath ("haarcascade_frontalface_alt.xml"));
            #if !UNITY_WSA_10_0
            if (cascade.empty ()) {
                Debug.LogError ("cascade file is not loaded. Please copy from “OpenCVForUnity/StreamingAssets/” to “Assets/StreamingAssets/” folder. ");
            }
            #endif

            #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 ();

            #endif
        }

        /// <summary>
        /// Raises the web cam 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;
            }

            grayMat = new Mat (webCamTextureMat.rows (), webCamTextureMat.cols (), CvType.CV_8UC1);

            faces = new MatOfRect ();
        }

        /// <summary>
        /// Raises the web cam texture to mat helper disposed event.
        /// </summary>
        public void OnWebCamTextureToMatHelperDisposed ()
        {
            Debug.Log ("OnWebCamTextureToMatHelperDisposed");

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

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

            if (faces != null)
                faces.Dispose ();
        }

        /// <summary>
        /// Raises the web cam 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, grayMat, Imgproc.COLOR_RGBA2GRAY);
                Imgproc.equalizeHist (grayMat, grayMat);
                
                
                if (cascade != null)
                    cascade.detectMultiScale (grayMat, faces, 1.1, 2, 2, // TODO: objdetect.CV_HAAR_SCALE_IMAGE
                        new Size (grayMat.cols () * 0.2, grayMat.rows () * 0.2), new Size ());
                
                
                OpenCVForUnity.CoreModule.Rect[] rects = faces.toArray ();
                for (int i = 0; i < rects.Length; i++) {
                    //              Debug.Log ("detect faces " + rects [i]);
                    
                    Imgproc.rectangle (rgbaMat, new Point (rects [i].x, rects [i].y), new Point (rects [i].x + rects [i].width, rects [i].y + rects [i].height), new Scalar (255, 0, 0, 255), 2);
                }
                
//                Imgproc.putText (rgbaMat, "W:" + rgbaMat.width () + " H:" + rgbaMat.height () + " SO:" + Screen.orientation, new Point (5, rgbaMat.rows () - 10), Imgproc.FONT_HERSHEY_SIMPLEX, 1.0, new Scalar (255, 255, 255, 255), 2, Imgproc.LINE_AA, false);
                
                Utils.fastMatToTexture2D (rgbaMat, texture);
            }
        }

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

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

            #if UNITY_WEBGL && !UNITY_EDITOR
            if (getFilePath_Coroutine != null) {
                StopCoroutine (getFilePath_Coroutine);
                ((IDisposable)getFilePath_Coroutine).Dispose ();
            }
            #endif
        }

        /// <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 ();
        }
    }
}