content: /*
   * 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 android.nfc.tech;
  
  import android.nfc.ErrorCodes;
  import android.nfc.FormatException;
  import android.nfc.INfcTag;
  import android.nfc.NdefMessage;
  import android.nfc.Tag;
  import android.nfc.TagLostException;
  import android.os.Bundle;
  import android.os.RemoteException;
  import android.util.Log;
  
  import java.io.IOException;
  
  /**
   * Provides access to NDEF content and operations on a {@link Tag}.
   *
   * <p>Acquire a {@link Ndef} object using {@link #get}.
   *
   * <p>NDEF is an NFC Forum data format. The data formats are implemented in
   * {@link android.nfc.NdefMessage} and
   * {@link android.nfc.NdefRecord}. This class provides methods to
   * retrieve and modify the {@link android.nfc.NdefMessage}
   * on a tag.
   *
   * <p>There are currently four NFC Forum standardized tag types that can be
   * formatted to contain NDEF data.
   * <ul>
   * <li>NFC Forum Type 1 Tag ({@link #NFC_FORUM_TYPE_1}), such as the Innovision Topaz
   * <li>NFC Forum Type 2 Tag ({@link #NFC_FORUM_TYPE_2}), such as the NXP MIFARE Ultralight
   * <li>NFC Forum Type 3 Tag ({@link #NFC_FORUM_TYPE_3}), such as Sony Felica
   * <li>NFC Forum Type 4 Tag ({@link #NFC_FORUM_TYPE_4}), such as NXP MIFARE Desfire
   * </ul>
   * It is mandatory for all Android devices with NFC to correctly enumerate
   * {@link Ndef} on NFC Forum Tag Types 1-4, and implement all NDEF operations
   * as defined in this class.
   *
   * <p>Some vendors have their own well defined specifications for storing NDEF data
   * on tags that do not fall into the above categories. Android devices with NFC
   * should enumerate and implement {@link Ndef} under these vendor specifications
   * where possible, but it is not mandatory. {@link #getType} returns a String
   * describing this specification, for example {@link #MIFARE_CLASSIC} is
   * <code>com.nxp.ndef.mifareclassic</code>.
   *
   * <p>Android devices that support MIFARE Classic must also correctly
   * implement {@link Ndef} on MIFARE Classic tags formatted to NDEF.
   *
   * <p>For guaranteed compatibility across all Android devices with NFC, it is
   * recommended to use NFC Forum Types 1-4 in new deployments of NFC tags
   * with NDEF payload. Vendor NDEF formats will not work on all Android devices.
   *
   * <p class="note"><strong>Note:</strong> Methods that perform I/O operations
   * require the {@link android.Manifest.permission#NFC} permission.
   */
  public final class Ndef extends BasicTagTechnology {
      private static final String TAG = "NFC";
  
      /** @hide */
      public static final int NDEF_MODE_READ_ONLY = 1;
      /** @hide */
      public static final int NDEF_MODE_READ_WRITE = 2;
      /** @hide */
      public static final int NDEF_MODE_UNKNOWN = 3;
  
      /** @hide */
      public static final String EXTRA_NDEF_MSG = "ndefmsg";
  
      /** @hide */
      public static final String EXTRA_NDEF_MAXLENGTH = "ndefmaxlength";
  
      /** @hide */
      public static final String EXTRA_NDEF_CARDSTATE = "ndefcardstate";
  
      /** @hide */
      public static final String EXTRA_NDEF_TYPE = "ndeftype";
  
      /** @hide */
      public static final int TYPE_OTHER = -1;
      /** @hide */
      public static final int TYPE_1 = 1;
      /** @hide */
      public static final int TYPE_2 = 2;
      /** @hide */
      public static final int TYPE_3 = 3;
      /** @hide */
      public static final int TYPE_4 = 4;
      /** @hide */
      public static final int TYPE_MIFARE_CLASSIC = 101;
      /** @hide */
      public static final int TYPE_ICODE_SLI = 102;
  
      /** @hide */
      public static final String UNKNOWN = "android.ndef.unknown";
  
      /** NFC Forum Tag Type 1 */
      public static final String NFC_FORUM_TYPE_1 = "org.nfcforum.ndef.type1";
      /** NFC Forum Tag Type 2 */
      public static final String NFC_FORUM_TYPE_2 = "org.nfcforum.ndef.type2";
      /** NFC Forum Tag Type 4 */
      public static final String NFC_FORUM_TYPE_3 = "org.nfcforum.ndef.type3";
      /** NFC Forum Tag Type 4 */
      public static final String NFC_FORUM_TYPE_4 = "org.nfcforum.ndef.type4";
      /** NDEF on MIFARE Classic */
      public static final String MIFARE_CLASSIC = "com.nxp.ndef.mifareclassic";
      /**
       * NDEF on iCODE SLI
       * @hide
       */
      public static final String ICODE_SLI = "com.nxp.ndef.icodesli";
  
      private final int mMaxNdefSize;
      private final int mCardState;
      private final NdefMessage mNdefMsg;
      private final int mNdefType;
  
      /**
       * Get an instance of {@link Ndef} for the given tag.
       *
       * <p>Returns null if {@link Ndef} was not enumerated in {@link Tag#getTechList}.
       * This indicates the tag is not NDEF formatted, or that this tag
       * is NDEF formatted but under a vendor specification that this Android
       * device does not implement.
       *
       * <p>Does not cause any RF activity and does not block.
       *
       * @param tag an NDEF compatible tag
       * @return Ndef object
       */
      public static Ndef get(Tag tag) {
          if (!tag.hasTech(TagTechnology.NDEF)) return null;
          try {
              return new Ndef(tag);
          } catch (RemoteException e) {
              return null;
          }
      }
  
      /**
       * Internal constructor, to be used by NfcAdapter
       * @hide
       */
      public Ndef(Tag tag) throws RemoteException {
          super(tag, TagTechnology.NDEF);
          Bundle extras = tag.getTechExtras(TagTechnology.NDEF);
          if (extras != null) {
              mMaxNdefSize = extras.getInt(EXTRA_NDEF_MAXLENGTH);
              mCardState = extras.getInt(EXTRA_NDEF_CARDSTATE);
              mNdefMsg = extras.getParcelable(EXTRA_NDEF_MSG);
              mNdefType = extras.getInt(EXTRA_NDEF_TYPE);
          } else {
              throw new NullPointerException("NDEF tech extras are null.");
          }
  
      }
  
      /**
       * Get the {@link NdefMessage} that was read from the tag at discovery time.
       *
       * <p>If the NDEF Message is modified by an I/O operation then it
       * will not be updated here, this function only returns what was discovered
       * when the tag entered the field.
       * <p>Note that this method may return null if the tag was in the
       * INITIALIZED state as defined by NFC Forum, as in this state the
       * tag is formatted to support NDEF but does not contain a message yet.
       * <p>Does not cause any RF activity and does not block.
       * @return NDEF Message read from the tag at discovery time, can be null
       */
      public NdefMessage getCachedNdefMessage() {
          return mNdefMsg;
      }
  
      /**
       * Get the NDEF tag type.
       *
       * <p>Returns one of {@link #NFC_FORUM_TYPE_1}, {@link #NFC_FORUM_TYPE_2},
       * {@link #NFC_FORUM_TYPE_3}, {@link #NFC_FORUM_TYPE_4},
       * {@link #MIFARE_CLASSIC} or another NDEF tag type that has not yet been
       * formalized in this Android API.
       *
       * <p>Does not cause any RF activity and does not block.
       *
       * @return a string representing the NDEF tag type
       */
      public String getType() {
          switch (mNdefType) {
              case TYPE_1:
                  return NFC_FORUM_TYPE_1;
              case TYPE_2:
                  return NFC_FORUM_TYPE_2;
              case TYPE_3:
                  return NFC_FORUM_TYPE_3;
              case TYPE_4:
                  return NFC_FORUM_TYPE_4;
              case TYPE_MIFARE_CLASSIC:
                  return MIFARE_CLASSIC;
              case TYPE_ICODE_SLI:
                  return ICODE_SLI;
              default:
                  return UNKNOWN;
          }
      }
  
      /**
       * Get the maximum NDEF message size in bytes.
       *
       * <p>Does not cause any RF activity and does not block.
       *
       * @return size in bytes
       */
      public int getMaxSize() {
          return mMaxNdefSize;
      }
  
      /**
       * Determine if the tag is writable.
       *
       * <p>NFC Forum tags can be in read-only or read-write states.
       *
       * <p>Does not cause any RF activity and does not block.
       *
       * <p>Requires {@link android.Manifest.permission#NFC} permission.
       *
       * @return true if the tag is writable
       */
      public boolean isWritable() {
          return (mCardState == NDEF_MODE_READ_WRITE);
      }
  
      /**
       * Read the current {@link android.nfc.NdefMessage} on this tag.
       *
       * <p>This always reads the current NDEF Message stored on the tag.
       *
       * <p>Note that this method may return null if the tag was in the
       * INITIALIZED state as defined by NFC Forum, as in that state the
       * tag is formatted to support NDEF but does not contain a message yet.
       *
       * <p>This is an I/O operation and will block until complete. It must
       * not be called from the main application thread. A blocked call will be canceled with
       * {@link IOException} if {@link #close} is called from another thread.
       *
       * <p class="note">Requires the {@link android.Manifest.permission#NFC} permission.
       *
       * @return the NDEF Message, can be null
       * @throws TagLostException if the tag leaves the field
       * @throws IOException if there is an I/O failure, or the operation is canceled
       * @throws FormatException if the NDEF Message on the tag is malformed
       */
      public NdefMessage getNdefMessage() throws IOException, FormatException {
          checkConnected();
  
          try {
              INfcTag tagService = mTag.getTagService();
              if (tagService == null) {
                  throw new IOException("Mock tags don't support this operation.");
              }
              int serviceHandle = mTag.getServiceHandle();
              if (tagService.isNdef(serviceHandle)) {
                  NdefMessage msg = tagService.ndefRead(serviceHandle);
                  if (msg == null && !tagService.isPresent(serviceHandle)) {
                      throw new TagLostException();
                  }
                  return msg;
              } else if (!tagService.isPresent(serviceHandle)) {
                  throw new TagLostException();
              } else {
                  return null;
              }
          } catch (RemoteException e) {
              Log.e(TAG, "NFC service dead", e);
              return null;
          }
      }
  
      /**
       * Overwrite the {@link NdefMessage} on this tag.
       *
       * <p>This is an I/O operation and will block until complete. It must
       * not be called from the main application thread. A blocked call will be canceled with
       * {@link IOException} if {@link #close} is called from another thread.
       *
       * <p class="note">Requires the {@link android.Manifest.permission#NFC} permission.
       *
       * @param msg the NDEF Message to write, must not be null
       * @throws TagLostException if the tag leaves the field
       * @throws IOException if there is an I/O failure, or the operation is canceled
       * @throws FormatException if the NDEF Message to write is malformed
       */
      public void writeNdefMessage(NdefMessage msg) throws IOException, FormatException {
          checkConnected();
  
          try {
              INfcTag tagService = mTag.getTagService();
              if (tagService == null) {
                  throw new IOException("Mock tags don't support this operation.");
              }
              int serviceHandle = mTag.getServiceHandle();
              if (tagService.isNdef(serviceHandle)) {
                  int errorCode = tagService.ndefWrite(serviceHandle, msg);
                  switch (errorCode) {
                      case ErrorCodes.SUCCESS:
                          break;
                      case ErrorCodes.ERROR_IO:
                          throw new IOException();
                      case ErrorCodes.ERROR_INVALID_PARAM:
                          throw new FormatException();
                      default:
                          // Should not happen
                          throw new IOException();
                  }
              }
              else {
                  throw new IOException("Tag is not ndef");
              }
          } catch (RemoteException e) {
              Log.e(TAG, "NFC service dead", e);
          }
      }
  
      /**
       * Indicates whether a tag can be made read-only with {@link #makeReadOnly()}.
       *
       * <p>Does not cause any RF activity and does not block.
       *
       * @return true if it is possible to make this tag read-only
       */
      public boolean canMakeReadOnly() {
          INfcTag tagService = mTag.getTagService();
          if (tagService == null) {
              return false;
          }
          try {
              return tagService.canMakeReadOnly(mNdefType);
          } catch (RemoteException e) {
              Log.e(TAG, "NFC service dead", e);
              return false;
          }
      }
  
      /**
       * Make a tag read-only.
       *
       * <p>This sets the CC field to indicate the tag is read-only,
       * and where possible permanently sets the lock bits to prevent
       * any further modification of the memory.
       * <p>This is a one-way process and cannot be reverted!
       *
       * <p>This is an I/O operation and will block until complete. It must
       * not be called from the main application thread. A blocked call will be canceled with
       * {@link IOException} if {@link #close} is called from another thread.
       *
       * <p class="note">Requires the {@link android.Manifest.permission#NFC} permission.
       *
       * @return true on success, false if it is not possible to make this tag read-only
       * @throws TagLostException if the tag leaves the field
       * @throws IOException if there is an I/O failure, or the operation is canceled
       */
      public boolean makeReadOnly() throws IOException {
          checkConnected();
  
          try {
              INfcTag tagService = mTag.getTagService();
              if (tagService == null) {
                  return false;
              }
              if (tagService.isNdef(mTag.getServiceHandle())) {
                  int errorCode = tagService.ndefMakeReadOnly(mTag.getServiceHandle());
                  switch (errorCode) {
                      case ErrorCodes.SUCCESS:
                          return true;
                      case ErrorCodes.ERROR_IO:
                          throw new IOException();
                      case ErrorCodes.ERROR_INVALID_PARAM:
                          return false;
                      default:
                          // Should not happen
                          throw new IOException();
                  }
             }
             else {
                 throw new IOException("Tag is not ndef");
             }
          } catch (RemoteException e) {
              Log.e(TAG, "NFC service dead", e);
              return false;
          }
      }
  }
  