VideoRecordController.java

package com.aimmac23.node;

import java.io.File;
import java.util.concurrent.ArrayBlockingQueue;
import java.util.concurrent.Future;
import java.util.concurrent.ThreadFactory;
import java.util.concurrent.ThreadPoolExecutor;
import java.util.concurrent.TimeUnit;
import java.util.logging.Logger;

public class VideoRecordController {
	
	private static final Logger log = Logger.getLogger(RecordVideoCallable.class.getSimpleName());

	private ThreadPoolExecutor executor;
	RecordVideoCallable currentCallable;
	private Future<File> currentFuture;
	private final int targetFramerate;

	private ScreenshotSource screenshotSource;
	
	public VideoRecordController() {
		executor = new ThreadPoolExecutor(1, 1, 1, TimeUnit.MINUTES, new ArrayBlockingQueue<Runnable>(5));
		executor.setThreadFactory(new RecorderThreadFactory());
		executor.prestartAllCoreThreads();
		
		String framerateString = System.getProperty("video.framerate", "15");
		String xvfbLocationString = System.getProperty("video.xvfbscreen", null);
		
		File xvfbLocation = null;
		if(xvfbLocationString != null) {
			File xvfbDirectory = new File(xvfbLocationString);
			File xvfbFile = new File(xvfbDirectory, "Xvfb_screen0");
			if(!xvfbFile.exists()) {
				throw new IllegalStateException("Xvfb Screen location not found: " + xvfbFile);
			}
			else if(!xvfbFile.isFile()) {
				throw new IllegalStateException("Xvfb Screen location is not a file: " + xvfbFile);
			}
			else {
				xvfbLocation = xvfbFile;
			}
		}
		else {
			xvfbLocation = null;
		}
		
		
		targetFramerate = Integer.parseInt(framerateString);
		
		log.info("Will attempt to record at  " + targetFramerate + " frames per second - adjust this value " +
		" by setting -Dvideo.framerate=<value>");
		
		try {
			if(xvfbLocation != null) {
				screenshotSource = new XvfbFileScreenshotSource(xvfbLocation);
				log.info("Using Xvfb acceleration");
			}
			else {
				screenshotSource = new RobotScreenshotSource();
			}
			
			screenshotSource.doStartupSanityChecks();
		}
		catch(Exception e) {
			throw new IllegalStateException("Could not create screenshot source for video encoder", e);
		}
		
	}
	
	public void startRecording() throws Exception {
		if(currentCallable != null) {
			throw new IllegalStateException("Video recording currently in progress, cannot record again");
		}
		
		currentCallable = new RecordVideoCallable(targetFramerate, screenshotSource);
		currentFuture = executor.submit(currentCallable);
	}
	
	public File stopRecording() throws Exception {
		if(currentCallable == null) {
			throw new IllegalStateException("Video recording not currently in progress, cannot stop!");
		}
		
		// sleep for half a second, to make sure we catch the end of the test
		// XXX: Do we really need this?
		Thread.sleep(500);
		
		currentCallable.stopRecording();
		currentCallable = null;
		return currentFuture.get();
	}
	
	public void resetRecording() {
		// if we are currently recording, stop
		if(currentCallable != null) {
			currentCallable.stopRecording();
			currentCallable = null;
			
			log.info("Stopped recording due to resetRecording being called");
		}
		else {
			log.info("resetRecording called but not recording - nothing to do");	
		}
		
	}
	class RecorderThreadFactory implements ThreadFactory {
		
		@Override
		public Thread newThread(Runnable r) {
			Thread thread = new Thread(r);
			thread.setDaemon(true);
			thread.setName("VideoRecordingThread");
			return thread;
		}
	}
}