/**
 * Copyright (C) 2010-2017 Gordon Fraser, Andrea Arcuri and EvoSuite
 * contributors
 *
 * This file is part of EvoSuite.
 *
 * EvoSuite is free software: you can redistribute it and/or modify it
 * under the terms of the GNU Lesser General Public License as published
 * by the Free Software Foundation, either version 3.0 of the License, or
 * (at your option) any later version.
 *
 * EvoSuite is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
 * Lesser Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with EvoSuite. If not, see <http://www.gnu.org/licenses/>.
 */
package org.evosuite.runtime.vfs;

import java.io.File;

import org.evosuite.runtime.RuntimeSettings;

/**
 * Parent class for both files and folders
 * 
 * @author arcuri
 *
 */
public abstract class FSObject {

	private volatile boolean readPermission;

	private volatile boolean writePermission;

	private volatile boolean executePermission;

	/**
	 * Normalized path uniquely identifying this file on the VFS
	 */
	protected volatile String path;

	/**
	 * The direct parent folder
	 */
	protected final VFolder parent;

	/**
	 * Even if file is removed from file system, some threads could still have
	 * references to it. So, long/expensive operations could be stopped here if
	 * file is deleted
	 */
	protected volatile boolean deleted;

	protected volatile long lastModified;

	public FSObject(String path,VFolder parent){		
		readPermission = true;
		writePermission = true;
		executePermission = true;		
		this.parent = parent;
		this.deleted = false;
		this.lastModified = getCurrentTimeMillis();

		if(isSpecialWindowsRoot(path)){
			//this means we are in Windows, and we are handling C: root folder
			this.path = path;
		} else {
			this.path = normalizePath(path);
		}
	}

	protected long getCurrentTimeMillis(){
		if(RuntimeSettings.mockJVMNonDeterminism){
			return org.evosuite.runtime.System.getCurrentTimeMillisForVFS();
		} else {
			return java.lang.System.currentTimeMillis();
		}
	}


	private boolean isSpecialWindowsRoot(String givenPath){
		return parent!=null && givenPath!=null && parent.isRoot() && givenPath.endsWith(":") && !File.separator.equals("/");
	}
	
	public boolean rename(String newPath){

		if(!isWritePermission() || !parent.isWritePermission()){
			return false;
		}

		path = newPath;

		return true; 
	}

	public boolean delete(){
		parent.removeChild(getName());
		deleted = true;
		return deleted;
	}

	public boolean isFolder(){
		return this instanceof VFolder;
	}

	public String getName(){
		if(path==null){
			return null;
		}
		
		if(isSpecialWindowsRoot(path)){
			return path;
		} else {
			return new File(path).getName();
		}
	}

	public String normalizePath(String rawPath){
		if(rawPath==null){
			return null;
		}
		return new File(rawPath).getAbsolutePath(); 
	}

	public boolean isReadPermission() {
		return readPermission;
	}


	public void setReadPermission(boolean readPermission) {
		this.readPermission = readPermission;
	}


	public boolean isWritePermission() {
		return writePermission;
	}


	public void setWritePermission(boolean writePermission) {
		this.writePermission = writePermission;
	}


	public boolean isExecutePermission() {
		return executePermission;
	}


	public void setExecutePermission(boolean executePermission) {
		this.executePermission = executePermission;
	}

	public String getPath() {
		return path == null ? "" : path;
	}

	/**
	 * Once a file/folder is deleted, it shouldn't be accessible any more from the VFS.
	 * But in case some thread holds a reference to this instance, we need to mark 
	 * that it is supposed to be deleted
	 * @return
	 */
	public boolean isDeleted() {
		return deleted;
	}

	@Override
	public String toString(){
		return getPath();
	}

	public long getLastModified() {
		return lastModified;
	}

	public boolean setLastModified(long lastModified) {
		//TODO check all of its callers, and  if should simulate time

		if(!this.isWritePermission()){
			return false;
		}
		this.lastModified = lastModified;
		return true;
	}

	public VFolder getParent() {
		return parent;
	}
}