Refactor ScreenshotUtils into element / ExtWebDriver methods, rename class to ScreenshotComparator and include only compare methods

src/main/java/org/finra/jtaf/ewd/ExtWebDriver.java

@@ -17,6 +17,8 @@
 
 package org.finra.jtaf.ewd;
 
+import java.io.File;
+import java.io.IOException;
 import java.util.List;
 import java.util.Map;
 
@@ -418,5 +420,16 @@ public List<String> getCurrentWindowIds() {
 	 * Selects the previously selected frame
 	 */
 	public void selectLastFrame();
+
+	/***
+	 * Take a screenshot of the browser content. Note that while using RemoteWebDriver sessions (ie: with
+	 * Sauce Labs), the screenshot will be a full page of content--not only the visible content where the
+	 * page is scrolled (as when using a non-RemoteWebDriver session).
+	 * 
+	 * @param toSaveAs - name of the file to save the picture in (Note: must be PNG)
+	 * @throws IOException
+	 * 		if problems saving file
+	 */
+	public void takeScreenshotOfPage(File toSaveAs) throws IOException;
 
 }

src/main/java/org/finra/jtaf/ewd/impl/DefaultExtWebDriver.java

@@ -17,6 +17,8 @@
 package org.finra.jtaf.ewd.impl;
 
 import java.io.ByteArrayInputStream;
+import java.io.File;
+import java.io.IOException;
 import java.io.InputStream;
 import java.util.HashMap;
 import java.util.HashSet;
@@ -35,18 +37,24 @@
 
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
+import org.apache.commons.io.FileUtils;
 import org.ccil.cowan.tagsoup.Parser;
 import org.finra.jtaf.ewd.ExtWebDriver;
 import org.finra.jtaf.ewd.HighlightProvider;
 import org.finra.jtaf.ewd.TimeOutException;
+import org.finra.jtaf.ewd.session.SessionManager;
 import org.finra.jtaf.ewd.widget.IElement;
 import org.openqa.selenium.Alert;
 import org.openqa.selenium.By;
 import org.openqa.selenium.Capabilities;
 import org.openqa.selenium.HasCapabilities;
 import org.openqa.selenium.JavascriptExecutor;
+import org.openqa.selenium.OutputType;
+import org.openqa.selenium.TakesScreenshot;
 import org.openqa.selenium.WebDriver;
 import org.openqa.selenium.WebElement;
+import org.openqa.selenium.remote.Augmenter;
+import org.openqa.selenium.remote.RemoteWebDriver;
 import org.w3c.dom.Node;
 import org.xml.sax.InputSource;
 import org.xml.sax.XMLReader;
@@ -884,4 +892,17 @@ public void setSessionId(String id) {
 	public String getSessionId() {
 		return this.sessionId;
 	}
+
+	@Override
+	public void takeScreenshotOfPage(File toSaveAs) throws IOException {
+		File screenshot;
+		if(!(wd instanceof RemoteWebDriver)) {
+			screenshot = ((TakesScreenshot) wd).getScreenshotAs(OutputType.FILE);		
+		}
+		else {
+			Augmenter augmenter = new Augmenter();
+			screenshot = ((TakesScreenshot) augmenter.augment(wd)).getScreenshotAs(OutputType.FILE);
+		}
+		FileUtils.copyFile(screenshot, toSaveAs);
+	}
 }

src/main/java/org/finra/jtaf/ewd/utils/ScreenshotComparator.java

@@ -0,0 +1,130 @@
+/*
+ * (C) Copyright 2013 Java Test Automation Framework Contributors.
+ *
+ * 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.
+ * 
+ */
+
+package org.finra.jtaf.ewd.utils;
+
+import java.awt.Color;
+import java.awt.image.BufferedImage;
+import java.io.File;
+import java.io.IOException;
+
+import javax.imageio.ImageIO;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.finra.jtaf.ewd.widget.IElement;
+import org.finra.jtaf.ewd.widget.WidgetException;
+
+/***
+ * To compare screenshots of elements
+ * 
+ * @author Pulitand
+ *
+ */
+public class ScreenshotComparator {
+
+	private static Logger log = LoggerFactory.getLogger(ScreenshotComparator.class);
+
+	/***
+	 * Prereq: The page on which you are taking the screenshot is fully loaded
+	 * 
+	 * Take a screenshot of the element identified by element and save the file as toSaveAs
+	 * (Note that this file should be saved as a png).
+	 * Test that the control picture, controlPicture, is both the same size as,
+	 * and, has a similarity value greater than or equal to the threshold.
+	 * 
+	 * @param element - the element to be tested
+	 * @param controlPicture - the file of the picture that will serve as the control
+	 * @param toSaveTestPictureAs - for example, save the file at "testData/textFieldWidget/screenshot.png"
+	 * @param threshold - you are asserting that the similarity between the two pictures
+	 * is a double greater than or equal to this double (between 0.0 and 1.0)
+	 * @throws Exception 
+	 */
+	public static boolean isElementSimilarToScreenshot(IElement element, File controlPicture, File
+			toSaveTestPictureAs, double threshold) throws IOException, WidgetException {
+
+		element.captureElementScreenshot(toSaveTestPictureAs);
+
+		log.info("Screenshot was successful. Comparing against control...");
+
+		BufferedImage var = ImageIO.read(toSaveTestPictureAs);
+		BufferedImage cont = ImageIO.read(controlPicture);
+
+		return isSimilar(var, cont, threshold);
+	}
+
+	/***
+	 * Prereq: The page on which you are taking the screenshot is fully loaded
+	 *
+	 * Take a screenshot of the element identified by element and save the file as toSaveAs
+	 * (Note that this file should be saved as a png).
+	 * Test that the control picture, controlPicture, is both the same size as,
+	 * and, has a similarity value greater than or equal to the default threshold of .85.
+	 * 
+	 * @param element - the element to be tested
+	 * @param controlPicture - the file of the picture that will serve as the control
+	 * @param toSaveTestPictureAs - for example, save the file at "testData/textFieldWidget/screenshot.png"
+	 * @throws WidgetException 
+	 * @throws IOException 
+	 * @throws Exception 
+	 */
+	public static boolean isElementSimilarToScreenshot(IElement element, File controlPicture, 
+			File toSaveTestPictureAs) throws IOException, WidgetException {
+		return isElementSimilarToScreenshot(element, controlPicture, toSaveTestPictureAs, .85);
+	}
+
+	private static boolean isSimilar(BufferedImage var, BufferedImage cont, double threshold) {
+		return similarity(var, cont) >= threshold;
+	}
+
+	//Returns a double between 0 and 1.0
+	private static double similarity(BufferedImage var, BufferedImage cont) {
+
+		double[] varArr = new double[var.getWidth()*var.getHeight()*3];
+		double[] contArr = new double[cont.getWidth()*cont.getHeight()*3];
+
+		if (varArr.length!=contArr.length)
+			throw new IllegalStateException("The pictures are different sizes!");
+
+		//unroll pixels
+		for(int i = 0; i < var.getHeight(); i++) {
+			for(int j = 0; j < var.getWidth(); j++) {
+				varArr[i*var.getWidth() + j + 0] = new Color(var.getRGB(j, i)).getRed();
+				contArr[i*cont.getWidth() + j + 0] = new Color(cont.getRGB(j, i)).getRed();
+				varArr[i*var.getWidth() + j + 1] = new Color(var.getRGB(j, i)).getGreen();
+				contArr[i*cont.getWidth() + j + 1] = new Color(cont.getRGB(j, i)).getGreen();
+				varArr[i*var.getWidth() + j + 2] = new Color(var.getRGB(j, i)).getBlue();
+				contArr[i*cont.getWidth() + j + 2] = new Color(cont.getRGB(j, i)).getBlue();
+			}
+		}
+
+		double mins=0;
+		double maxs=0;
+		for(int i=0;i!=varArr.length;i++){
+			if (varArr[i]>contArr[i]){
+				mins+=contArr[i];
+				maxs+=varArr[i];
+			} else {
+				mins+=varArr[i];
+				maxs+=contArr[i];
+			}
+		}
+		return mins/maxs;
+	}
+
+
+}