/*
 * Copyright (c) 2011 Google Inc.
 *
 * 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
 */
package com.google.eclipse.protobuf.ui.preferences.paths;

import org.eclipse.core.resources.IProject;
import org.eclipse.core.runtime.IPath;
import org.eclipse.core.runtime.Path;

/**
 * ${project} variable.
 *
 * @author alruiz@google.com (Alex Ruiz)
 */
public class ProjectVariable {
  private static final String VARIABLE_VALUE = "${project}";

  public static IPath replaceProjectNameWithProjectVariable(IPath path, IProject project) {
    return switchProjectSegments(path, project.getName(), VARIABLE_VALUE);
  }

  public static IPath replaceProjectVariableWithProjectName(IPath path, IProject project) {
    return switchProjectSegments(path, VARIABLE_VALUE, project.getName());
  }

  private static IPath switchProjectSegments(IPath path, String currentSegment, String newSegment) {
    if (!currentSegment.equals(path.segment(0))) {
      return path;
    }
    IPath newPath = Path.fromOSString(newSegment);
    newPath = newPath.append(path.removeFirstSegments(1));
    if (path.isAbsolute()) {
      newPath = newPath.makeAbsolute();
    }
    return newPath;
  }
}