/*
    * Licensed to the Apache Software Foundation (ASF) under one or more
    * contributor license agreements.  See the NOTICE file distributed with
    * this work for additional information regarding copyright ownership.
    * The ASF licenses this file to You 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 org.apache.commons.vfs2.provider.ram;
  
  import java.io.ByteArrayInputStream;
  import java.io.IOException;
  import java.io.InputStream;
  import java.io.OutputStream;
  
  import org.apache.commons.lang3.ArrayUtils;
  import org.apache.commons.vfs2.FileObject;
  import org.apache.commons.vfs2.FileSystemException;
  import org.apache.commons.vfs2.FileSystemOptions;
  import org.apache.commons.vfs2.FileType;
  import org.apache.commons.vfs2.RandomAccessContent;
  import org.apache.commons.vfs2.provider.AbstractFileName;
  import org.apache.commons.vfs2.provider.AbstractFileObject;
  import org.apache.commons.vfs2.util.FileObjectUtils;
  import org.apache.commons.vfs2.util.RandomAccessMode;
  
  /**
   * A RAM File contains a single RAM FileData instance, it provides methods to access the data by implementing FileObject
   * interface.
   */
  public class RamFileObject extends AbstractFileObject<RamFileSystem> {
  
      /**
       * RAM File Object Data.
       */
      private RamFileData data;
  
      /**
       * @param name The name of the file.
       * @param fs The FileSystem.
       */
      protected RamFileObject(final AbstractFileName name, final RamFileSystem fs) {
          super(name, fs);
          this.getAbstractFileSystem().attach(this);
      }
  
      private void save() throws FileSystemException {
          this.getAbstractFileSystem().save(this);
      }
  
      /*
       * (non-Javadoc)
       *
       * @see org.apache.commons.vfs2.provider.AbstractFileObject#doGetType()
       */
      @Override
      protected FileType doGetType() throws Exception {
          return data.getType();
      }
  
      /*
       * (non-Javadoc)
       *
       * @see org.apache.commons.vfs2.provider.AbstractFileObject#doListChildren()
       */
      @Override
      protected String[] doListChildren() throws Exception {
          return this.getAbstractFileSystem().listChildren(this.getName());
      }
  
      /*
       * (non-Javadoc)
       *
       * @see org.apache.commons.vfs2.provider.AbstractFileObject#doGetContentSize()
       */
      @Override
      protected long doGetContentSize() throws Exception {
          return this.size();
      }
  
      /*
       * (non-Javadoc)
       *
       * @see org.apache.commons.vfs2.provider.AbstractFileObject#doGetInputStream()
       */
      @Override
      protected InputStream doGetInputStream(final int bufferSize) throws Exception {
          // VFS-210: ram allows to gather an input stream even from a directory. So we need to check the type anyway.
          if (!getType().hasContent()) {
              throw new FileSystemException("vfs.provider/read-not-file.error", getName());
          }
 
         return new ByteArrayInputStream(this.data.getContent());
     }
 
     /*
      * (non-Javadoc)
      *
      * @see org.apache.commons.vfs2.provider.AbstractFileObject#doGetOutputStream(boolean)
      */
     @Override
     protected OutputStream doGetOutputStream(final boolean bAppend) throws Exception {
         if (!bAppend) {
             this.data.setContent(ArrayUtils.EMPTY_BYTE_ARRAY);
         }
         return new RamFileOutputStream(this);
     }
 
     /*
      * (non-Javadoc)
      *
      * @see org.apache.commons.vfs2.provider.AbstractFileObject#doDelete()
      */
     @Override
     protected void doDelete() throws Exception {
 
         if (this.isContentOpen()) {
             throw new FileSystemException(this.getName() + " cannot be deleted while the file is openg");
         }
         getAbstractFileSystem().delete(this);
     }
 
     /*
      * (non-Javadoc)
      *
      * @see org.apache.commons.vfs2.provider.AbstractFileObject#doGetLastModifiedTime()
      */
     @Override
     protected long doGetLastModifiedTime() throws Exception {
         return data.getLastModified();
     }
 
     /*
      * (non-Javadoc)
      *
      * @see org.apache.commons.vfs2.provider.AbstractFileObject#doSetLastModifiedTime(long)
      */
     /** @since 2.0 */
     @Override
     protected boolean doSetLastModifiedTime(final long modtime) throws Exception {
         data.setLastModified(modtime);
         return true;
     }
 
     /*
      * (non-Javadoc)
      *
      * @see org.apache.commons.vfs2.provider.AbstractFileObject#doCreateFolder()
      */
     @Override
     protected void doCreateFolder() throws Exception {
         this.injectType(FileType.FOLDER);
         this.save();
     }
 
     /*
      * (non-Javadoc)
      *
      * @see org.apache.commons.vfs2.provider.AbstractFileObject#doRename(org.apache.commons.vfs2.FileObject)
      */
     @Override
     protected void doRename(final FileObject newFile) throws Exception {
         final RamFileObject/org/apache/commons/vfs2/provider/ram/RamFileObject.html#RamFileObject">RamFileObject newRamFileObject = (RamFileObject) FileObjectUtils.getAbstractFileObject(newFile);
         getAbstractFileSystem().rename(this, newRamFileObject);
     }
 
     /*
      * (non-Javadoc)
      *
      * @see org.apache.commons.vfs2.provider.AbstractFileObject#doGetRandomAccessContent(
      * org.apache.commons.vfs2.util.RandomAccessMode)
      */
     @Override
     protected RandomAccessContent doGetRandomAccessContent(final RandomAccessMode mode) throws Exception {
         return new RamFileRandomAccessContent(this, mode);
     }
 
     /*
      * (non-Javadoc)
      *
      * @see org.apache.commons.vfs2.provider.AbstractFileObject#doAttach()
      */
     @Override
     protected void doAttach() throws Exception {
         this.getAbstractFileSystem().attach(this);
     }
 
     /**
      * @return Returns the data.
      */
     RamFileData getData() {
         return data;
     }
 
     /**
      * @param data The data to set.
      */
     void setData(final RamFileData data) {
         this.data = data;
     }
 
     /*
      * (non-Javadoc)
      *
      * @see org.apache.commons.vfs2.provider.AbstractFileObject#injectType(org.apache.commons.vfs2.FileType)
      */
     @Override
     protected void injectType(final FileType fileType) {
         this.data.setType(fileType);
         super.injectType(fileType);
     }
 
     /*
      * (non-Javadoc)
      *
      * @see org.apache.commons.vfs2.provider.AbstractFileObject#endOutput()
      */
     @Override
     protected void endOutput() throws Exception {
         super.endOutput();
         this.save();
     }
 
     /**
      * @return Returns the size of the {@link RamFileData}.
      */
     int size() {
         return data == null ? 0 : data.size();
     }
 
     /**
      * @param newSize The new buffer size.
      * @throws IOException if the new size exceeds the limit
      */
     synchronized void resize(final long newSize) throws IOException {
         final RamFileSystem afs = getAbstractFileSystem();
         final FileSystemOptions afsOptions = afs.getFileSystemOptions();
         if (afsOptions != null) {
             final long maxSize = RamFileSystemConfigBuilder.getInstance().getLongMaxSize(afsOptions);
             if (afs.size() + newSize - this.size() > maxSize) {
                 throw new IOException("FileSystem capacity (" + maxSize + ") exceeded.");
             }
         }
         this.data.resize(newSize);
     }
 
 }