001// License: GPL. For details, see Readme.txt file.
002package org.openstreetmap.gui.jmapviewer.tilesources;
003
004import java.awt.Image;
005import java.io.IOException;
006import java.io.InputStream;
007import java.net.MalformedURLException;
008import java.net.URL;
009import java.util.ArrayList;
010import java.util.List;
011import java.util.Locale;
012import java.util.concurrent.Callable;
013import java.util.concurrent.ExecutionException;
014import java.util.concurrent.Future;
015import java.util.concurrent.FutureTask;
016import java.util.concurrent.TimeUnit;
017import java.util.concurrent.TimeoutException;
018import java.util.regex.Pattern;
019
020import javax.imageio.ImageIO;
021import javax.xml.parsers.DocumentBuilder;
022import javax.xml.parsers.DocumentBuilderFactory;
023import javax.xml.parsers.ParserConfigurationException;
024import javax.xml.xpath.XPath;
025import javax.xml.xpath.XPathConstants;
026import javax.xml.xpath.XPathExpression;
027import javax.xml.xpath.XPathExpressionException;
028import javax.xml.xpath.XPathFactory;
029
030import org.openstreetmap.gui.jmapviewer.Coordinate;
031import org.openstreetmap.gui.jmapviewer.JMapViewer;
032import org.openstreetmap.gui.jmapviewer.interfaces.ICoordinate;
033import org.w3c.dom.Document;
034import org.w3c.dom.Node;
035import org.w3c.dom.NodeList;
036import org.xml.sax.InputSource;
037import org.xml.sax.SAXException;
038
039public class BingAerialTileSource extends AbstractTMSTileSource {
040
041    private static final String API_KEY = "Arzdiw4nlOJzRwOz__qailc8NiR31Tt51dN2D7cm57NrnceZnCpgOkmJhNpGoppU";
042    private static volatile Future<List<Attribution>> attributions; // volatile is required for getAttribution(), see below.
043    private static String imageUrlTemplate;
044    private static Integer imageryZoomMax;
045    private static String[] subdomains;
046
047    private static final Pattern subdomainPattern = Pattern.compile("\\{subdomain\\}");
048    private static final Pattern quadkeyPattern = Pattern.compile("\\{quadkey\\}");
049    private static final Pattern culturePattern = Pattern.compile("\\{culture\\}");
050    private String brandLogoUri;
051
052    /**
053     * Constructs a new {@code BingAerialTileSource}.
054     */
055    public BingAerialTileSource() {
056        super(new TileSourceInfo("Bing", null, null));
057    }
058
059    /**
060     * Constructs a new {@code BingAerialTileSource}.
061     * @param info imagery info
062     */
063    public BingAerialTileSource(TileSourceInfo info) {
064        super(info);
065    }
066
067    protected static class Attribution {
068        private String attribution;
069        private int minZoom;
070        private int maxZoom;
071        private Coordinate min;
072        private Coordinate max;
073    }
074
075    @Override
076    public String getTileUrl(int zoom, int tilex, int tiley) throws IOException {
077        // make sure that attribution is loaded. otherwise subdomains is null.
078        if (getAttribution() == null)
079            throw new IOException("Attribution is not loaded yet");
080
081        int t = (zoom + tilex + tiley) % subdomains.length;
082        String subdomain = subdomains[t];
083
084        String url = imageUrlTemplate;
085        url = subdomainPattern.matcher(url).replaceAll(subdomain);
086        url = quadkeyPattern.matcher(url).replaceAll(computeQuadTree(zoom, tilex, tiley));
087
088        return url;
089    }
090
091    protected URL getAttributionUrl() throws MalformedURLException {
092        return new URL("http://dev.virtualearth.net/REST/v1/Imagery/Metadata/Aerial?include=ImageryProviders&output=xml&key="
093                + API_KEY);
094    }
095
096    protected List<Attribution> parseAttributionText(InputSource xml) throws IOException {
097        try {
098            DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
099            DocumentBuilder builder = factory.newDocumentBuilder();
100            Document document = builder.parse(xml);
101
102            XPathFactory xPathFactory = XPathFactory.newInstance();
103            XPath xpath = xPathFactory.newXPath();
104            imageUrlTemplate = xpath.compile("//ImageryMetadata/ImageUrl/text()").evaluate(document);
105            imageUrlTemplate = culturePattern.matcher(imageUrlTemplate).replaceAll(Locale.getDefault().toString());
106            imageryZoomMax = Integer.valueOf(xpath.compile("//ImageryMetadata/ZoomMax/text()").evaluate(document));
107
108            NodeList subdomainTxt = (NodeList) xpath.compile("//ImageryMetadata/ImageUrlSubdomains/string/text()")
109                    .evaluate(document, XPathConstants.NODESET);
110            subdomains = new String[subdomainTxt.getLength()];
111            for (int i = 0; i < subdomainTxt.getLength(); i++) {
112                subdomains[i] = subdomainTxt.item(i).getNodeValue();
113            }
114
115            brandLogoUri = xpath.compile("/Response/BrandLogoUri/text()").evaluate(document);
116
117            XPathExpression attributionXpath = xpath.compile("Attribution/text()");
118            XPathExpression coverageAreaXpath = xpath.compile("CoverageArea");
119            XPathExpression zoomMinXpath = xpath.compile("ZoomMin/text()");
120            XPathExpression zoomMaxXpath = xpath.compile("ZoomMax/text()");
121            XPathExpression southLatXpath = xpath.compile("BoundingBox/SouthLatitude/text()");
122            XPathExpression westLonXpath = xpath.compile("BoundingBox/WestLongitude/text()");
123            XPathExpression northLatXpath = xpath.compile("BoundingBox/NorthLatitude/text()");
124            XPathExpression eastLonXpath = xpath.compile("BoundingBox/EastLongitude/text()");
125
126            NodeList imageryProviderNodes = (NodeList) xpath.compile("//ImageryMetadata/ImageryProvider")
127                    .evaluate(document, XPathConstants.NODESET);
128            List<Attribution> attributions = new ArrayList<>(imageryProviderNodes.getLength());
129            for (int i = 0; i < imageryProviderNodes.getLength(); i++) {
130                Node providerNode = imageryProviderNodes.item(i);
131
132                String attribution = attributionXpath.evaluate(providerNode);
133
134                NodeList coverageAreaNodes = (NodeList) coverageAreaXpath.evaluate(providerNode, XPathConstants.NODESET);
135                for (int j = 0; j < coverageAreaNodes.getLength(); j++) {
136                    Node areaNode = coverageAreaNodes.item(j);
137                    Attribution attr = new Attribution();
138                    attr.attribution = attribution;
139
140                    attr.maxZoom = Integer.parseInt(zoomMaxXpath.evaluate(areaNode));
141                    attr.minZoom = Integer.parseInt(zoomMinXpath.evaluate(areaNode));
142
143                    Double southLat = Double.valueOf(southLatXpath.evaluate(areaNode));
144                    Double northLat = Double.valueOf(northLatXpath.evaluate(areaNode));
145                    Double westLon = Double.valueOf(westLonXpath.evaluate(areaNode));
146                    Double eastLon = Double.valueOf(eastLonXpath.evaluate(areaNode));
147                    attr.min = new Coordinate(southLat, westLon);
148                    attr.max = new Coordinate(northLat, eastLon);
149
150                    attributions.add(attr);
151                }
152            }
153
154            return attributions;
155        } catch (SAXException e) {
156            System.err.println("Could not parse Bing aerials attribution metadata.");
157            e.printStackTrace();
158        } catch (ParserConfigurationException e) {
159            e.printStackTrace();
160        } catch (XPathExpressionException e) {
161            e.printStackTrace();
162        }
163        return null;
164    }
165
166    @Override
167    public int getMaxZoom() {
168        if (imageryZoomMax != null)
169            return imageryZoomMax;
170        else
171            return 22;
172    }
173
174    @Override
175    public boolean requiresAttribution() {
176        return true;
177    }
178
179    @Override
180    public String getAttributionLinkURL() {
181        //return "http://bing.com/maps"
182        // FIXME: I've set attributionLinkURL temporarily to ToU URL to comply with bing ToU
183        // (the requirement is that we have such a link at the bottom of the window)
184        return "http://go.microsoft.com/?linkid=9710837";
185    }
186
187    @Override
188    public Image getAttributionImage() {
189        try {
190            final InputStream imageResource = JMapViewer.class.getResourceAsStream("images/bing_maps.png");
191            if (imageResource != null) {
192                return ImageIO.read(imageResource);
193            } else {
194                // Some Linux distributions (like Debian) will remove Bing logo from sources, so get it at runtime
195                for (int i = 0; i < 5 && getAttribution() == null; i++) {
196                    // Makes sure attribution is loaded
197                    if (JMapViewer.debug) {
198                        System.out.println("Bing attribution attempt " + (i+1));
199                    }
200                }
201                if (brandLogoUri != null && !brandLogoUri.isEmpty()) {
202                    System.out.println("Reading Bing logo from "+brandLogoUri);
203                    return ImageIO.read(new URL(brandLogoUri));
204                }
205            }
206        } catch (IOException e) {
207            System.err.println("Error while retrieving Bing logo: "+e.getMessage());
208        }
209        return null;
210    }
211
212    @Override
213    public String getAttributionImageURL() {
214        return "http://opengeodata.org/microsoft-imagery-details";
215    }
216
217    @Override
218    public String getTermsOfUseText() {
219        return null;
220    }
221
222    @Override
223    public String getTermsOfUseURL() {
224        return "http://opengeodata.org/microsoft-imagery-details";
225    }
226
227    protected Callable<List<Attribution>> getAttributionLoaderCallable() {
228        return new Callable<List<Attribution>>() {
229
230            @Override
231            public List<Attribution> call() throws Exception {
232                int waitTimeSec = 1;
233                while (true) {
234                    try {
235                        InputSource xml = new InputSource(getAttributionUrl().openStream());
236                        List<Attribution> r = parseAttributionText(xml);
237                        System.out.println("Successfully loaded Bing attribution data.");
238                        return r;
239                    } catch (IOException ex) {
240                        System.err.println("Could not connect to Bing API. Will retry in " + waitTimeSec + " seconds.");
241                        Thread.sleep(waitTimeSec * 1000L);
242                        waitTimeSec *= 2;
243                    }
244                }
245            }
246        };
247    }
248
249    protected List<Attribution> getAttribution() {
250        if (attributions == null) {
251            // see http://www.cs.umd.edu/~pugh/java/memoryModel/DoubleCheckedLocking.html
252            synchronized (BingAerialTileSource.class) {
253                if (attributions == null) {
254                  final FutureTask<List<Attribution>> loader = new FutureTask<>(getAttributionLoaderCallable());
255                  new Thread(loader, "bing-attribution-loader").start();
256                  attributions = loader;
257                }
258            }
259        }
260        try {
261            return attributions.get(0, TimeUnit.MILLISECONDS);
262        } catch (TimeoutException ex) {
263            System.err.println("Bing: attribution data is not yet loaded.");
264        } catch (ExecutionException ex) {
265            throw new RuntimeException(ex.getCause());
266        } catch (InterruptedException ign) {
267            System.err.println("InterruptedException: " + ign.getMessage());
268        }
269        return null;
270    }
271
272    @Override
273    public String getAttributionText(int zoom, ICoordinate topLeft, ICoordinate botRight) {
274        try {
275            final List<Attribution> data = getAttribution();
276            if (data == null)
277                return "Error loading Bing attribution data";
278            StringBuilder a = new StringBuilder();
279            for (Attribution attr : data) {
280                if (zoom <= attr.maxZoom && zoom >= attr.minZoom) {
281                    if (topLeft.getLon() < attr.max.getLon() && botRight.getLon() > attr.min.getLon()
282                            && topLeft.getLat() > attr.min.getLat() && botRight.getLat() < attr.max.getLat()) {
283                        a.append(attr.attribution);
284                        a.append(' ');
285                    }
286                }
287            }
288            return a.toString();
289        } catch (Exception e) {
290            e.printStackTrace();
291        }
292        return "Error loading Bing attribution data";
293    }
294
295    private static String computeQuadTree(int zoom, int tilex, int tiley) {
296        StringBuilder k = new StringBuilder();
297        for (int i = zoom; i > 0; i--) {
298            char digit = 48;
299            int mask = 1 << (i - 1);
300            if ((tilex & mask) != 0) {
301                digit += 1;
302            }
303            if ((tiley & mask) != 0) {
304                digit += 2;
305            }
306            k.append(digit);
307        }
308        return k.toString();
309    }
310}