content: /*
   * Copyright (C) 2013 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 dev.dworks.apps.anexplorer.cursor;
  
  import android.database.AbstractCursor;
  import android.database.Cursor;
  import android.os.Bundle;
  
  /**
   * Cursor wrapper that adds columns to identify which root a document came from.
   */
  public class RootCursorWrapper extends AbstractCursor {
      private final String mAuthority;
      private final String mRootId;
  
      private final Cursor mCursor;
      private final int mCount;
  
      private final String[] mColumnNames;
  
      private final int mAuthorityIndex;
      private final int mRootIdIndex;
  
      public static final String COLUMN_AUTHORITY = "android:authority";
      public static final String COLUMN_ROOT_ID = "android:rootId";
  
      public RootCursorWrapper(String authority, String rootId, Cursor cursor, int maxCount) {
          mAuthority = authority;
          mRootId = rootId;
          mCursor = cursor;
  
          final int count = cursor.getCount();
          if (maxCount > 0 && count > maxCount) {
              mCount = maxCount;
          } else {
              mCount = count;
          }
  
          if (cursor.getColumnIndex(COLUMN_AUTHORITY) != -1
                  || cursor.getColumnIndex(COLUMN_ROOT_ID) != -1) {
              throw new IllegalArgumentException("Cursor contains internal columns!");
          }
          final String[] before = cursor.getColumnNames();
          mColumnNames = new String[before.length + 2];
          System.arraycopy(before, 0, mColumnNames, 0, before.length);
          mAuthorityIndex = before.length;
          mRootIdIndex = before.length + 1;
          mColumnNames[mAuthorityIndex] = COLUMN_AUTHORITY;
          mColumnNames[mRootIdIndex] = COLUMN_ROOT_ID;
      }
  
      @Override
      public Bundle getExtras() {
          return mCursor.getExtras();
      }
  
      @Override
      public void close() {
          super.close();
          mCursor.close();
      }
  
      @Override
      public boolean onMove(int oldPosition, int newPosition) {
          return mCursor.moveToPosition(newPosition);
      }
  
      @Override
      public String[] getColumnNames() {
          return mColumnNames;
      }
  
      @Override
      public int getCount() {
          return mCount;
      }
  
      @Override
      public double getDouble(int column) {
          return mCursor.getDouble(column);
      }
  
      @Override
      public float getFloat(int column) {
          return mCursor.getFloat(column);
      }
  
      @Override
      public int getInt(int column) {
          return mCursor.getInt(column);
      }
  
      @Override
      public long getLong(int column) {
          return mCursor.getLong(column);
      }
  
      @Override
      public short getShort(int column) {
          return mCursor.getShort(column);
      }
  
      @Override
      public String getString(int column) {
          if (column == mAuthorityIndex) {
              return mAuthority;
          } else if (column == mRootIdIndex) {
              return mRootId;
          } else {
              return mCursor.getString(column);
          }
      }
  
      @Override
      public int getType(int column) {
          return mCursor.getType(column);
      }
  
      @Override
      public boolean isNull(int column) {
          return mCursor.isNull(column);
      }
  }
  