/*
* Copyright 2012 ZXing.Net authors
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
*      http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/

using System.Threading;

using UnityEngine;

using ZXing;
using ZXing.QrCode;

public class BarcodeCam : MonoBehaviour
{
    public BarcodeCam self;
    // Texture for encoding test
    public Texture2D encoded;

    private WebCamTexture camTexture;
    private Thread qrThread;

    private Color32[] color32;
    private int W, H;

    private Rect screenRect;

    private bool isQuit;

    public string LastResult;
    private bool shouldEncodeNow;

    public BarcodeCam()
    {
        self = this;
    }

    void Start()
    {
        encoded = new Texture2D(256, 256);
        LastResult = "http://www.google.com";
        shouldEncodeNow = true;

        screenRect = new Rect(Screen.width * 0.1f/2, -Screen.height * 0.2f/2, Screen.width*0.9f, Screen.height*0.8f);

        camTexture = new WebCamTexture();
        camTexture.requestedHeight = Screen.height; // 480;
        camTexture.requestedWidth = Screen.width; //640;
        OnEnable();

        qrThread = new Thread(DecodeQR);
        qrThread.Start();
    }

    void OnGUI()
    {
        GUI.DrawTexture(screenRect, camTexture, ScaleMode.ScaleToFit);
    }

    void OnEnable()
    {
        if (camTexture != null)
        {
            camTexture.Play();
            W = camTexture.width;
            H = camTexture.height;

            if (color32 == null)
            {
                color32 = camTexture.GetPixels32();
            }
        }
    }

    void OnDisable()
    {
        if (camTexture != null)
        {
            camTexture.Pause();
        }
    }

    void OnDestroy()
    {
        if(qrThread != null)
            qrThread.Abort();
        if(camTexture != null)
            camTexture.Stop();
    }

    // It's better to stop the thread by itself rather than abort it.
    void OnApplicationQuit()
    {
        isQuit = true;
    }


    //void Update()
    //{
    // encode the last found
    //    var textForEncoding = LastResult;
    //    if (shouldEncodeNow &&
    //        textForEncoding != null)
    //    {
    //        var c = Encode(textForEncoding, encoded.width, encoded.height);
    //        encoded.SetPixels32(c);
    //        encoded.Apply();
    //        shouldEncodeNow = false;
    //    }
    //}

    void DecodeQR()
    {
        // create a reader with a custom luminance source
        var barcodeReader = new BarcodeReader { AutoRotate = false, TryHarder = false };

        while (true)
        {
            if (isQuit)
                break;

            try
            {
                if (color32 != null)
                {
                    // decode the current frame
                    var result = barcodeReader.Decode(color32, W, H);
                    if (result != null)
                    {
                        LastResult = result.Text;
                        shouldEncodeNow = true;
                        print(result.Text);
                    }
                }

                // Sleep a little bit and set the signal to get the next frame
                Thread.Sleep(200);
                color32 = null;
            }
            catch(System.Exception e)
            {
                Debug.LogError(e);
            }
        }
    }

    public static Color32[] Encode(string textForEncoding, int width, int height)
    {
        var writer = new BarcodeWriter
        {
            Format = BarcodeFormat.QR_CODE,
            Options = new QrCodeEncodingOptions
            {
                Height = height,
                Width = width
            }
        };
        return writer.Write(textForEncoding);
    }
}