content: /*******************************************************************************
   * Copyright (c) 2009, 2019 Mountainminds GmbH & Co. KG and Contributors
   * All rights reserved. This program and the accompanying materials
   * are made available under the terms of the Eclipse Public License v1.0
   * which accompanies this distribution, and is available at
   * http://www.eclipse.org/legal/epl-v10.html
   *
   * Contributors:
   *    Marc R. Hoffmann - initial API and implementation
   *    
   *******************************************************************************/
  package org.jacoco.report.internal;
  
  import java.io.IOException;
  import java.io.OutputStream;
  import java.util.HashMap;
  import java.util.Map;
  
  import org.jacoco.report.IMultiReportOutput;
  
  /**
   * Logical representation of a folder in the output structure. This utility
   * ensures valid and unique file names and helps to create relative links.
   */
  public class ReportOutputFolder {
  
  	private final IMultiReportOutput output;
  
  	private final ReportOutputFolder parent;
  
  	private final String path;
  
  	/** Cached sub-folder instances to guarantee stable normalization */
  	private final Map<String, ReportOutputFolder> subFolders = new HashMap<String, ReportOutputFolder>();
  
  	private final NormalizedFileNames fileNames;
  
  	/**
  	 * Creates a new root folder for the given output.
  	 * 
  	 * @param output
  	 *            output for generated files
  	 */
  	public ReportOutputFolder(final IMultiReportOutput output) {
  		this(output, null, "");
  	}
  
  	/**
  	 * Creates a new root folder for the given output.
  	 * 
  	 * @param output
  	 *            output for generated files
  	 */
  	private ReportOutputFolder(final IMultiReportOutput output,
  			final ReportOutputFolder parent, final String path) {
  		this.output = output;
  		this.parent = parent;
  		this.path = path;
  		fileNames = new NormalizedFileNames();
  	}
  
  	/**
  	 * Creates a sub-folder with the given name.
  	 * 
  	 * @param name
  	 *            name of the sub-folder
  	 * @return handle for output into the sub-folder
  	 */
  	public ReportOutputFolder subFolder(final String name) {
  		final String normalizedName = normalize(name);
  		ReportOutputFolder folder = subFolders.get(normalizedName);
  		if (folder != null) {
  			return folder;
  		}
  		folder = new ReportOutputFolder(output, this, path + normalizedName
  				+ "/");
  		subFolders.put(normalizedName, folder);
  		return folder;
  	}
  
  	/**
  	 * Creates a new file in this folder with the given local name.
  	 * 
  	 * @param name
  	 *            name of the sub-folder
  	 * @return handle for output into the sub-folder
  	 * @throws IOException
  	 *             if the file creation fails
  	 */
  	public OutputStream createFile(final String name) throws IOException {
  		return output.createFile(path + normalize(name));
  	}
  
  	/**
  	 * Returns a link relative to a given base to a resource within this folder.
  	 * 
  	 * @param base
  	 *            base to create the relative link from
  	 * @param name
  	 *            name of the file or folder in this folder
  	 * @return relative link
  	 * @throws IllegalArgumentException
  	 *             if this folder and the base do not have the same root
  	 */
  	public String getLink(final ReportOutputFolder base, final String name) {
  		if (base.isAncestorOf(this)) {
  			return this.path.substring(base.path.length()) + normalize(name);
  		}
  		if (base.parent == null) {
  			throw new IllegalArgumentException("Folders with different roots.");
  		}
  		return "../" + this.getLink(base.parent, name);
  	}
  
  	private boolean isAncestorOf(final ReportOutputFolder folder) {
  		if (this == folder) {
  			return true;
  		}
  		return folder.parent == null ? false : isAncestorOf(folder.parent);
  	}
  
  	private String normalize(final String name) {
  		return fileNames.getFileName(name);
  	}
  
  }
  