ch.unifr.pai.twice.widgets.mpproxy.client.ScreenShotDistributor.java Source code

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Here is the source code for ch.unifr.pai.twice.widgets.mpproxy.client.ScreenShotDistributor.java
Source

package ch.unifr.pai.twice.widgets.mpproxy.client;

/*
 * Copyright 2013 Oliver Schmid
 * 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.
 */
import ch.unifr.pai.twice.widgets.mpproxy.shared.Rewriter;
import ch.unifr.pai.twice.widgets.mpproxy.shared.URLParser;

import com.google.gwt.core.client.GWT;
import com.google.gwt.dom.client.Document;
import com.google.gwt.http.client.Request;
import com.google.gwt.http.client.RequestBuilder;
import com.google.gwt.http.client.RequestCallback;
import com.google.gwt.http.client.RequestException;
import com.google.gwt.http.client.Response;
import com.google.gwt.user.client.Timer;
import com.google.gwt.user.client.Window;

/**
 * Takes a snapshot of the current HTML DOM structure, removes script tags and submits the content to the server in regular intervals
 * 
 * @author Oliver Schmid
 * 
 */
public class ScreenShotDistributor {
    private String lastSent;
    private int lastTop = -1;
    private int lastLeft = -1;
    private final Timer t = new Timer() {

        @Override
        public void run() {
            sendScreenShot();
        }
    };

    /**
     * Begin to update the server with screenshots
     */
    public void start() {
        t.scheduleRepeating(1000);
    }

    /**
     * Stop the updating of the server with screenshots
     */
    public void stop() {
        t.cancel();
    }

    /**
     * Send the screenshot to the server
     */
    public void sendScreenShot() {
        String screen = Document.get().getDocumentElement().getInnerHTML();
        if (!screen.equals(lastSent) || lastLeft != Window.getScrollLeft() || lastTop != Window.getScrollTop()) {
            String url = Window.Location.getHref();
            URLParser p = new URLParser(url, Rewriter.getServletPath(Window.Location.getHref()));
            RequestBuilder rb = new RequestBuilder(RequestBuilder.POST,
                    GWT.getModuleBaseURL() + "manager?url=" + p.getProxyBasePath() + "&width="
                            + Window.getClientWidth() + "&height=" + Window.getClientHeight() + "&top="
                            + Window.getScrollTop() + "&left=" + Window.getScrollLeft());
            lastSent = screen;
            lastLeft = Window.getScrollLeft();
            lastTop = Window.getScrollTop();
            screen = screen.replace('\n', ' ');
            screen = screen.replaceAll("<body", "<body><div class=\"readOnlyView\" style=\"width:"
                    + Window.getClientWidth() + "; height:" + Window.getClientHeight() + ";\"");
            screen = screen.replaceAll("<\\/body>", "</div></body>");
            screen = screen.replaceAll("(<script).*?(\\/script>)", "");
            try {
                rb.sendRequest(screen, new RequestCallback() {

                    @Override
                    public void onResponseReceived(Request request, Response response) {
                        // TODO Auto-generated method stub

                    }

                    @Override
                    public void onError(Request request, Throwable exception) {
                        Window.alert("Screenshot sent");
                    }
                });
            } catch (RequestException e) {
                e.printStackTrace();
            }
        }
    }

}