/*
 *  RapidMiner
 *
 *  Copyright (C) 2001-2011 by Rapid-I and the contributors
 *
 *  Complete list of developers available at our web site:
 *
 *       http://rapid-i.com
 *
 *  This program is free software: you can redistribute it and/or modify
 *  it under the terms of the GNU Affero General Public License as published by
 *  the Free Software Foundation, either version 3 of the License, or
 *  (at your option) any later version.
 *
 *  This program 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 Affero General Public License for more details.
 *
 *  You should have received a copy of the GNU Affero General Public License
 *  along with this program.  If not, see http://www.gnu.org/licenses/.
 */
package com.rapidminer.operator.meta;

import java.io.File;
import java.io.IOException;
import java.util.Enumeration;
import java.util.LinkedList;
import java.util.List;
import java.util.regex.Pattern;
import java.util.zip.ZipEntry;
import java.util.zip.ZipException;
import java.util.zip.ZipFile;

import com.rapidminer.operator.OperatorDescription;
import com.rapidminer.operator.OperatorException;
import com.rapidminer.operator.UserError;
import com.rapidminer.operator.nio.file.FileObject;
import com.rapidminer.operator.nio.file.ZipEntryObject;
import com.rapidminer.operator.ports.InputPort;
import com.rapidminer.operator.ports.Port;
import com.rapidminer.operator.ports.metadata.MetaData;
import com.rapidminer.operator.ports.metadata.SimplePrecondition;
import com.rapidminer.parameter.ParameterType;
import com.rapidminer.parameter.ParameterTypeFile;
import com.rapidminer.parameter.ParameterTypeString;
import com.rapidminer.parameter.PortProvider;
import com.rapidminer.parameter.conditions.InputPortNotConnectedCondition;

/**
 * This operator loops over the entries of a zip file.
 * 
 * @author Marius Helf
 *
 */
public class ZippedFileIterator extends AbstractFileIterator {
	public static final String PARAMETER_ZIPFILE = "filename";
	public static final String PARAMETER_INTERNAL_DIRECTORY = "internal_directory";
	
	private InputPort fileInputPort = getInputPorts().createPort("file");

	
	public ZippedFileIterator(OperatorDescription description) {
		super(description);

		fileInputPort.addPrecondition(new SimplePrecondition(fileInputPort, new MetaData(FileObject.class)) {
        	@Override
        	protected boolean isMandatory() {
        		return false;
        	}
        });
	}
	
	@Override
	public void doWork() throws OperatorException {
		super.doWork();
	}

	@Override
	protected void iterate(Object currentParent, Pattern filter, boolean iterateSubDirs, boolean iterateFiles, boolean recursive) throws OperatorException {
		
		ZipFile zipFile = null;
		File physicalZipFile = null;
		if (fileInputPort.isConnected()) {
			FileObject zipFileObject = fileInputPort.getDataOrNull();
			if (zipFileObject == null) {
				throw new UserError(this, 122, FileObject.class.getName());
			}
			physicalZipFile = zipFileObject.getFile();
		} else {
			physicalZipFile = getParameterAsFile(PARAMETER_ZIPFILE);
		}
		
		try {
			zipFile = new ZipFile(physicalZipFile);
		} catch (ZipException e) {
			throw new UserError(this, 403, physicalZipFile.getAbsolutePath() + " (" + e.getMessage() + ").");
		} catch (IOException e) {
			throw new UserError(this, 301, physicalZipFile.getAbsolutePath());
		}
		
		String rootDirectory = getParameterAsString(PARAMETER_INTERNAL_DIRECTORY);
		
		Enumeration<? extends ZipEntry> entries = zipFile.entries();
		while (entries.hasMoreElements()) {
			ZipEntry currentEntry = entries.nextElement();
			String fullPath = currentEntry.getName();
			String[] pathParts = fullPath.split("/");
			String fileName = pathParts[pathParts.length-1];
			StringBuilder builder = new StringBuilder();
			for (int i = 0; i < pathParts.length-1; ++i) {
				builder.append(pathParts[i]);
				if (i != pathParts.length-2) {
					builder.append("/");
				}
			}
			String parentPath = builder.toString();

			if ( (iterateFiles && !currentEntry.isDirectory()) || (iterateSubDirs && currentEntry.isDirectory()) ) {
				if ( (recursive && parentPath.startsWith(rootDirectory)) || (   !recursive && (  (rootDirectory.isEmpty() && parentPath.isEmpty()) || (!rootDirectory.isEmpty() && parentPath.equals(rootDirectory))  )   ) ) {
					if (matchesFilter(filter, fileName, fullPath, parentPath)) {
						FileObject fileObject = new ZipEntryObject(currentEntry, zipFile);
						doWorkForSingleIterationStep(fileName, fullPath, parentPath, fileObject);
					}
				}
			}
		}
	}

	
	@Override
	public List<ParameterType> getParameterTypes() {
        List<ParameterType> types = new LinkedList<ParameterType>();
		
		ParameterType type;

		type = new ParameterTypeFile(PARAMETER_ZIPFILE, "The zipfile over whose entries this operator iterates.", ".zip", true, false);
		type.registerDependencyCondition(new InputPortNotConnectedCondition(this, new PortProvider() {
			@Override
			public Port getPort() {
				return fileInputPort;
			}
		}, true));

		types.add(type);
		
		type = new ParameterTypeString(PARAMETER_INTERNAL_DIRECTORY, "The directory inside the zipfile from which the entries should be taken.", "");
		type.setExpert(true);
		type.setOptional(true);
		types.add(type);

		types.addAll(super.getParameterTypes());
		return types;
	}
}