fix: a shared Google Maps route navigates to its destination

app/src/main/java/org/surfsite/gexporter/SharedLocation.java

@@ -15,8 +15,10 @@
 import java.net.URL;
 import java.net.URLDecoder;
 import java.net.URLEncoder;
+import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.HashMap;
+import java.util.List;
 import java.util.Locale;
 import java.util.Map;
 import java.util.regex.Matcher;
@@ -45,6 +47,11 @@ public class SharedLocation {
     private static final Pattern GOOGLE_PLACE = Pattern.compile("!3d" + NUM + "!4d" + NUM);
     private static final Pattern GOOGLE_VIEWPORT = Pattern.compile("@" + NUM + "," + NUM);
     private static final Pattern GOOGLE_PLACE_NAME = Pattern.compile("/maps/place/([^/@?]+)");
+    // Directions (/maps/dir/<start>/<stops>/<destination>/@viewport/data=...):
+    // the data part lists the position of each named stop, as !1d<lon>!2d<lat>
+    // or (Google Maps app, 2026) as !3d<lat>!4d<lon>.
+    private static final Pattern GOOGLE_DIR_STOP = Pattern.compile("!1d" + NUM + "!2d" + NUM + "|!3d" + NUM + "!4d" + NUM);
+    private static final Pattern GOOGLE_DIR_QUERY = Pattern.compile("[?&](?:destination|daddr)=" + NUM + "(?:,|%2C)\\+?" + NUM, Pattern.CASE_INSENSITIVE);
     private static final Pattern QUERY_COORDS = Pattern.compile("[?&](?:q|ll|query|destination|daddr|center|sll)=" + NUM + "(?:,|%2C)\\+?" + NUM, Pattern.CASE_INSENSITIVE);
     // In the EU, Google redirects every request without this cookie to the
     // consent dialog, so following a place URL would loop through it.
@@ -110,7 +117,9 @@ public static SharedLocation parse(String text) {
             }
         }
 
-        Matcher c = PLAIN_COORDS.matcher(text);
+        // Coordinates inside a link are for the link parsers above: a
+        // directions link's viewport is not a place.
+        Matcher c = PLAIN_COORDS.matcher(URL_PATTERN.matcher(text).replaceAll(" "));
         while (c.find()) {
             SharedLocation loc = fromStrings(name, c.group(1), c.group(2));
             if (loc != null) {
@@ -329,6 +338,9 @@ private static SharedLocation parseGeoUri(String uri, String fallbackName) {
     }
 
     private static SharedLocation parseGoogleUrl(String url, String fallbackName) {
+        if (googleDirStops(url) != null) {
+            return parseGoogleDirections(url, fallbackName);
+        }
         String placeName = googlePlaceName(url);
         String name = placeName != null ? placeName : fallbackName;
 
@@ -344,6 +356,63 @@ private static SharedLocation parseGoogleUrl(String url, String fallbackName) {
         return null;
     }
 
+    /**
+     * The destination of a directions link, which is its last stop. The
+     * viewport (@lat,lon) is never used: it shows the whole route, and its
+     * center is somewhere between start and destination.
+     */
+    private static SharedLocation parseGoogleDirections(String url, String fallbackName) {
+        String placeName = googlePlaceName(url);
+        String name = placeName != null ? placeName : fallbackName;
+
+        Matcher m = GOOGLE_DIR_QUERY.matcher(url);
+        if (m.find()) {
+            return fromStrings(name, m.group(1), m.group(2));
+        }
+        List<String> stops = googleDirStops(url);
+        if (stops.isEmpty()) {
+            return null;
+        }
+        // a destination given as coordinates has no entry in the data part
+        m = PLAIN_COORDS.matcher(stops.get(stops.size() - 1));
+        if (m.matches()) {
+            return fromStrings(fallbackName, m.group(1), m.group(2));
+        }
+        m = GOOGLE_DIR_STOP.matcher(url);
+        String lat = null;
+        String lon = null;
+        while (m.find()) {
+            if (m.group(1) != null) {
+                lon = m.group(1);
+                lat = m.group(2);
+            } else {
+                lat = m.group(3);
+                lon = m.group(4);
+            }
+        }
+        return lat != null ? fromStrings(name, lat, lon) : null;
+    }
+
+    /** The stops of a /maps/dir/ link (start first, destination last), or null. */
+    private static List<String> googleDirStops(String url) {
+        int i = url.indexOf("/maps/dir/");
+        if (i < 0) {
+            return null;
+        }
+        String rest = url.substring(i + "/maps/dir/".length()).split("[?#]", 2)[0];
+        List<String> stops = new ArrayList<>();
+        for (String segment : rest.split("/")) {
+            if (segment.startsWith("@") || segment.startsWith("data=")) {
+                break;
+            }
+            String stop = urlDecode(segment).trim();
+            if (!stop.isEmpty()) {
+                stops.add(stop);
+            }
+        }
+        return stops;
+    }
+
     private static boolean isGoogle(String url) {
         String host;
         try {
@@ -355,10 +424,22 @@ private static boolean isGoogle(String url) {
                 || host.matches("(?:.+\\.)?google\\.[a-z.]+");
     }
 
-    /** "<name>, <address>" from /maps/place/<text> or ?q=<text>, or null. */
+    /**
+     * "<name>, <address>" from /maps/place/<text>, ?q=<text> or the
+     * destination of a directions link, or null.
+     */
     private static String googlePlaceText(String url) {
-        Matcher m = GOOGLE_PLACE_NAME.matcher(url);
-        String text = m.find() ? urlDecode(m.group(1)) : queryParam(url, "q");
+        String text;
+        List<String> stops = googleDirStops(url);
+        if (stops != null) {
+            text = queryParam(url, "destination");
+            if (text == null) {
+                text = stops.isEmpty() ? null : stops.get(stops.size() - 1);
+            }
+        } else {
+            Matcher m = GOOGLE_PLACE_NAME.matcher(url);
+            text = m.find() ? urlDecode(m.group(1)) : queryParam(url, "q");
+        }
         if (text == null) {
             return null;
         }

app/src/test/java/org/surfsite/gexporter/TestSharedLocation.java

@@ -147,6 +147,51 @@ public void organicMapsPageIsNoLocation() {
         assertNull(SharedLocation.parse("https://omaps.app/get"));
     }
 
+    // Shape of a Google Maps "Share directions" link once its short link is
+    // resolved: start, destination, the route's viewport, and in data= the
+    // position of each named stop as !1d<lon>!2d<lat>.
+    private static final String DIRECTIONS = "https://www.google.com/maps/dir/M%C3%BCnchen/Zugspitze/"
+            + "@47.7869,11.0712,9z/data=!3m1!4b1!4m13!4m12"
+            + "!1m5!1m1!1s0x479e75f9a38c5fd9:0x10cb84a7db1987d!2m2!1d11.5819806!2d48.1351253"
+            + "!1m5!1m1!1s0x479d0b6a6d6e2a0b:0x2e8d7b9f2a3c!2m2!1d10.9863!2d47.4211";
+
+    @Test
+    public void directionsGoToTheDestinationNotTheViewport() {
+        assertLoc(SharedLocation.parse(DIRECTIONS), "Zugspitze", 47.4211, 10.9863);
+    }
+
+    @Test
+    public void directionsFromTheGoogleMapsApp() {
+        // Shape of a 2026 "Share directions" from the Google Maps app, once
+        // resolved: the start is the current position, the destination is
+        // named and its position is in data= as !3d<lat>!4d<lon>.
+        String url = "https://www.google.com/maps/dir/48.1,11.5/Some+Shop+GmbH/data=!4m12!4m11!1m1!4e1"
+                + "!1m5!1m4!1s0x0:0x0!8m2!3d47.4211!4d10.9863!2m1!11b1!3e2?utm_source=mstt_0";
+        assertLoc(SharedLocation.parse(url), "Some Shop GmbH", 47.4211, 10.9863);
+    }
+
+    @Test
+    public void directionsWithCoordinateStops() {
+        assertLoc(SharedLocation.parse("https://www.google.com/maps/dir/48.1351253,11.5819806/47.4211,10.9863/@47.8,11.2,9z"),
+                SharedLocation.DEFAULT_NAME, 47.4211, 10.9863);
+    }
+
+    @Test
+    public void directionsApiLink() {
+        assertLoc(SharedLocation.parse("https://www.google.com/maps/dir/?api=1&destination=47.4211,10.9863"),
+                SharedLocation.DEFAULT_NAME, 47.4211, 10.9863);
+    }
+
+    @Test
+    public void directionsWithoutPositionsAreGeocoded() throws Exception {
+        String url = "https://www.google.com/maps/dir/M%C3%BCnchen/Zugspitze/@47.7869,11.0712,9z";
+        assertNull(SharedLocation.parse(url));
+        FakeFetcher f = new FakeFetcher();
+        f.redirects.put("https://maps.app.goo.gl/dir123", url);
+        f.bodies.put(nominatim("Zugspitze"), "[{\"lat\":\"47.4211\",\"lon\":\"10.9863\"}]");
+        assertLoc(SharedLocation.resolve("https://maps.app.goo.gl/dir123", f), "Zugspitze", 47.4211, 10.9863);
+    }
+
     @Test
     public void unknownLinkNeedsResolving() {
         assertNull(SharedLocation.parse("Stephansdom\nhttps://maps.app.goo.gl/abc123"));