add SmartPoster support.

Fix off by 1 in URI handling.

Change-Id: I2007ca20c5411dd3a19aa96ea023652ed293cdc5

apps/Tag/src/com/android/apps/tag/NdefUtil.java

@@ -16,17 +16,22 @@
 
 package com.android.apps.tag;
 
+import android.util.Log;
 import com.google.common.base.Preconditions;
 import com.google.common.collect.BiMap;
 import com.google.common.collect.ImmutableBiMap;
+import com.google.common.collect.Iterables;
 import com.google.common.primitives.Bytes;
+import com.trustedlogic.trustednfc.android.NdefMessage;
 import com.trustedlogic.trustednfc.android.NdefRecord;
 
 import java.io.UnsupportedEncodingException;
 import java.net.URI;
 import java.net.URISyntaxException;
 import java.nio.charset.Charsets;
+import java.util.ArrayList;
 import java.util.Arrays;
+import java.util.List;
 
 /**
  * Utilities for dealing with conversions to and from NdefRecords.
@@ -133,7 +138,7 @@ public class NdefUtil {
         String prefix = URI_PREFIX_MAP.get(payload[0]);
         byte[] fullUri = Bytes.concat(
                 prefix.getBytes(Charsets.UTF_8),
-                Arrays.copyOfRange(payload, 1, payload.length - 1));
+                Arrays.copyOfRange(payload, 1, payload.length));
 
         return new URI(new String(fullUri, Charsets.UTF_8));
     }
@@ -185,7 +190,50 @@ public class NdefUtil {
                     textEncoding);
         } catch (UnsupportedEncodingException e) {
             // should never happen unless we get a malformed tag.
-            throw new RuntimeException(e);
+            throw new IllegalArgumentException(e);
+        }
+    }
+
+    public static boolean isText(NdefRecord record) {
+        try {
+            toText(record);
+            return true;
+        } catch (IllegalArgumentException e) {
+            return false;
+        }
+    }
+
+    public static Iterable<String> getTextFields(NdefMessage message) {
+        return Iterables.filter(getObjects(message), String.class);
+    }
+
+    public static Iterable<URI> getURIs(NdefMessage message) {
+        return Iterables.filter(getObjects(message), URI.class);
+    }
+
+    /**
+     * Parse the provided {@code NdefMessage}, extracting all known
+     * objects from the message.  Typically this list will consist of
+     * {@link String}s corresponding to NDEF text records, or {@link URI}s
+     * corresponding to NDEF URI records.
+     * <p>
+     * TODO: Is this API too generic?  Should we keep it?
+     */
+    private static Iterable<Object> getObjects(NdefMessage message) {
+        try {
+            List<Object> retval = new ArrayList<Object>();
+            for (NdefRecord record : message.getRecords()) {
+                if (isURI(record)) {
+                    retval.add(toURI(record));
+                } else if (isText(record)) {
+                    retval.add(toText(record));
+                } else if (SmartPoster.isPoster(record)) {
+                    retval.add(SmartPoster.from(record));
+                }
+            }
+            return retval;
+        } catch (URISyntaxException e) {
+            throw new IllegalArgumentException(e);
         }
     }
 }

apps/Tag/src/com/android/apps/tag/SmartPoster.java

@@ -0,0 +1,95 @@
+/*
+ * Copyright (C) 2010 The Android Open Source Project
+ *
+ * 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 com.android.apps.tag;
+
+import com.google.common.base.Preconditions;
+import com.google.common.collect.Iterables;
+import com.trustedlogic.trustednfc.android.NdefMessage;
+import com.trustedlogic.trustednfc.android.NdefRecord;
+import com.trustedlogic.trustednfc.android.NfcException;
+
+import javax.annotation.Nullable;
+import java.net.URI;
+import java.util.Arrays;
+
+/**
+ * A representation of an NFC Forum "Smart Poster".
+ */
+public class SmartPoster {
+
+    /**
+     * NFC Forum Smart Poster Record Type Definition section 3.2.1.
+     *
+     * "The Title record for the service (there can be many of these in
+     * different languages, but a language MUST NOT be repeated).
+     * This record is optional."
+
+     */
+    private final String titleRecord;
+
+    /**
+     * NFC Forum Smart Poster Record Type Definition section 3.2.1.
+     *
+     * "The URI record. This is the core of the Smart Poster, and all other
+     * records are just metadata about this record. There MUST be one URI
+     * record and there MUST NOT be more than one."
+     */
+    private final URI uriRecord;
+
+    private SmartPoster(URI uri, @Nullable String title) {
+        uriRecord = Preconditions.checkNotNull(uri);
+        titleRecord = title;
+    }
+
+    public URI getURI() {
+        return uriRecord;
+    }
+
+    /**
+     * Returns the title of the smartposter.  This may be {@code null}.
+     */
+    public String getTitle() {
+        return titleRecord;
+    }
+
+    public static SmartPoster from(NdefRecord record) {
+        Preconditions.checkArgument(record.getTnf() == NdefRecord.TNF_WELL_KNOWN_TYPE);
+        Preconditions.checkArgument(Arrays.equals(record.getType(), NdefRecord.TYPE_SMART_POSTER));
+        try {
+            NdefMessage subRecords = new NdefMessage(record.getPayload());
+            URI uri = Iterables.getOnlyElement(NdefUtil.getURIs(subRecords));
+            Iterable<String> textFields = NdefUtil.getTextFields(subRecords);
+            String title = null;
+            if (!Iterables.isEmpty(textFields)) {
+                title = Iterables.get(textFields, 0);
+            }
+
+            return new SmartPoster(uri, title);
+        } catch (NfcException e) {
+            throw new IllegalArgumentException(e);
+        }
+    }
+
+    public static boolean isPoster(NdefRecord record) {
+        try {
+            from(record);
+            return true;
+        } catch (IllegalArgumentException e) {
+            return false;
+        }
+    }
+}

apps/Tag/src/com/android/apps/tag/TagDBHelper.java

@@ -52,7 +52,7 @@ public class TagDBHelper extends SQLiteOpenHelper {
      * consists of the text "NFC Forum Type 4 Tag" in english combined with
      * the URL "http://www.nxp.com/nfc"
      */
-    private static final byte[] REAL_NFC_MSG = new byte[] {
+    public static final byte[] REAL_NFC_MSG = new byte[] {
             (byte) 0xd1,                   // MB=1 ME=1 CF=0 SR=1 IL=0 TNF=001
             (byte) 0x02,                   // Type Length = 2
             (byte) 0x2b,                   // Payload Length = 43

apps/Tag/tests/src/com/android/apps/tag/SmartPosterTest.java

@@ -0,0 +1,33 @@
+/*
+ * Copyright (C) 2010 The Android Open Source Project
+ *
+ * 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 com.android.apps.tag;
+
+import android.test.AndroidTestCase;
+import com.trustedlogic.trustednfc.android.NdefMessage;
+
+/**
+ * Tests for {@link SmartPoster}.
+ */
+public class SmartPosterTest extends AndroidTestCase {
+    public void testSmartPoster() throws Exception {
+        NdefMessage msg = new NdefMessage(TagDBHelper.REAL_NFC_MSG);
+
+        SmartPoster poster = SmartPoster.from(msg.getRecords()[0]);
+        assertEquals("NFC Forum Type 4 Tag", poster.getTitle());
+        assertEquals("http://www.nxp.com/nfc", poster.getURI().toString());
+    }
+}