content: /*
   * Copyright (C) 2018 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.internal.telephony.uicc.euicc.apdu;
  
  import java.util.ArrayList;
  import java.util.List;
  
  /**
   * A helper class to build a request for sending APDU commands. It contains a few convenient methods
   * to add different APDU commands to the request.
   *
   * @hide
   */
  public class RequestBuilder {
      // The maximum bytes of the data of an APDU command. If more bytes need to be sent than this
      // limit, we need to separate them into multiple commands.
      private static final int MAX_APDU_DATA_LEN = 0xFF;
      // The maximum bytes of the data of an extended APDU command. If more bytes need to be sent than
      // this limit, we need to separate them into multiple commands.
      private static final int MAX_EXT_APDU_DATA_LEN = 0xFFFF;
  
      // Parameters used by STORE DATA command sent to ISD-R, defined by SGP.22 v2.0.
      private static final int CLA_STORE_DATA = 0x80;
      private static final int INS_STORE_DATA = 0xE2;
      private static final int P1_STORE_DATA_INTERM = 0x11;
      private static final int P1_STORE_DATA_END = 0x91;
  
      private final int mChannel;
      private final int mMaxApduDataLen;
      private final List<ApduCommand> mCommands = new ArrayList<>();
  
      /**
       * Adds an APDU command by specifying every parts. The parameters are defined as in
       * GlobalPlatform Card Specification v.2.3.
       */
      public void addApdu(int cla, int ins, int p1, int p2, int p3, String cmdHex) {
          mCommands.add(new ApduCommand(mChannel, cla, ins, p1, p2, p3, cmdHex));
      }
  
      /**
       * Adds an APDU command with given command data. P3 will be the length of the command data
       * bytes. The parameters are defined as in GlobalPlatform Card Specification v.2.3.
       */
      public void addApdu(int cla, int ins, int p1, int p2, String cmdHex) {
          mCommands.add(new ApduCommand(mChannel, cla, ins, p1, p2, cmdHex.length() / 2, cmdHex));
      }
  
      /**
       * Adds an APDU command with empty command data. The parameters are defined as in GlobalPlatform
       * Card Specification v.2.3.
       */
      public void addApdu(int cla, int ins, int p1, int p2) {
          mCommands.add(new ApduCommand(mChannel, cla, ins, p1, p2, 0, ""));
      }
  
      /**
       * Adds a STORE DATA command. Long command length of which is larger than {@link
       * #mMaxApduDataLen} will be automatically split into multiple ones.
       *
       * @param cmdHex The STORE DATA command in a hex string as defined in GlobalPlatform Card
       *     Specification v.2.3.
       */
      public void addStoreData(String cmdHex) {
          final int cmdLen = mMaxApduDataLen * 2;
          int startPos = 0;
          int totalLen = cmdHex.length() / 2;
          int totalSubCmds = totalLen == 0 ? 1 : (totalLen + mMaxApduDataLen - 1) / mMaxApduDataLen;
          for (int i = 1; i < totalSubCmds; ++i) {
              String data = cmdHex.substring(startPos, startPos + cmdLen);
              addApdu(CLA_STORE_DATA, INS_STORE_DATA, P1_STORE_DATA_INTERM, i - 1, data);
              startPos += cmdLen;
          }
          String data = cmdHex.substring(startPos);
          addApdu(CLA_STORE_DATA, INS_STORE_DATA, P1_STORE_DATA_END, totalSubCmds - 1, data);
      }
  
      List<ApduCommand> getCommands() {
          return mCommands;
      }
  
      RequestBuilder(int channel, boolean supportExtendedApdu) {
          mChannel = channel;
          mMaxApduDataLen = supportExtendedApdu ? MAX_EXT_APDU_DATA_LEN : MAX_APDU_DATA_LEN;
      }
  }
  