package com.reactlibrary;

import com.facebook.react.bridge.ReactApplicationContext;
import com.facebook.react.bridge.ReactContextBaseJavaModule;
import com.facebook.react.bridge.ReactMethod;
import com.facebook.react.bridge.Callback;
import android.annotation.TargetApi;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.Canvas;
import android.graphics.Paint;
import android.graphics.PaintFlagsDrawFilter;
import android.util.Base64;
import android.view.View;
import android.view.View.MeasureSpec;
import android.webkit.WebView;
import android.webkit.WebViewClient;
public class RNHtmlBase64imageModule extends ReactContextBaseJavaModule {

  private final ReactApplicationContext reactContext;

  public RNHtmlBase64imageModule(ReactApplicationContext reactContext) {
    super(reactContext);
    this.reactContext = reactContext;
  }

  @Override
  public String getName() {
    return "RNHtmlBase64image";
  }
  @TargetApi(Build.VERSION_CODES.LOLLIPOP) 
  @ReactMethod
  public String convert(String htmlString, float scale) {
     try {
      if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) {
        WebView.enableSlowWholeDocumentDraw();
      }
        final WebView webView = new WebView(reactContext);
        webView.setInitialScale(scale);
        webView.loadData(htmlString, "text/html; charset=UTF-8", null);
        webView.setWebViewClient(new WebViewClient() {
            public void onPageFinished(WebView view, String url) {
                webView.measure(MeasureSpec.makeMeasureSpec(MeasureSpec.UNSPECIFIED, MeasureSpec.UNSPECIFIED),
                        MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED));
                webView.layout(0, 0, webView.getMeasuredWidth(),
                        webView.getMeasuredHeight());
                webView.setDrawingCacheEnabled(true);
                webView.buildDrawingCache();
                Bitmap bm = Bitmap.createBitmap(webView.getMeasuredWidth(),
                        webView.getMeasuredHeight(), Bitmap.Config.ARGB_8888);
                Canvas bigcanvas = new Canvas(bm);
                Paint paint = new Paint();
                int iHeight = bm.getHeight();
                bigcanvas.drawBitmap(bm, 0, iHeight, paint);
                webView.draw(bigcanvas);
                ByteArrayOutputStream byteArrayOutputStream = new ByteArrayOutputStream();
                bm.compress(Bitmap.CompressFormat.JPEG, 100, byteArrayOutputStream);
                byte[] byteArray = byteArrayOutputStream.toByteArray();
                String encoded = Base64.encodeToString(byteArray, Base64.DEFAULT);
                return encoded; 
            }
        });
    } catch(Exception e) {
        return "ERROR";
     }
  }
}