// Copyright (c) 2008-2009 Nokia Corporation and/or its subsidiary(-ies).

// All rights reserved.

// This component and the accompanying materials are made available

// under the terms of "Eclipse Public License v1.0"

// which accompanies this distribution, and is available

// at the URL "http://www.eclipse.org/legal/epl-v10.html".

//

// Initial Contributors:

// Nokia Corporation - initial contribution.

//

// Contributors:

//

// Description:

// ${file_name}

// 

//

package com.symbian.smt.gui.smtwidgets;

import java.io.File;

import java.io.IOException;

import java.io.InputStream;

import java.net.MalformedURLException;

import java.net.URL;

import java.net.URLConnection;

import java.util.List;

import javax.xml.parsers.DocumentBuilder;

import javax.xml.parsers.DocumentBuilderFactory;

import javax.xml.parsers.ParserConfigurationException;

import org.w3c.dom.Document;

import org.xml.sax.ErrorHandler;

import org.xml.sax.SAXException;

import org.xml.sax.SAXParseException;

import com.symbian.smt.gui.Logger;

import com.symbian.smt.gui.XmlFileValidator;

/**

 * @author barbararosi-schwartz

 * 

 */

public class SystemDefinitionFileSelectionValidator extends

		XmlFileValidator implements IXmlFileInputValidator {

	private List<String> sysdefFilenames;

	private InputStream urlInputStream;

	public SystemDefinitionFileSelectionValidator(List<String> filenames) {

		super();

		this.sysdefFilenames = filenames;

	}

	private void closeInputStream() {

		if (urlInputStream != null) {

			try {

				urlInputStream.close();

			} catch (IOException ignore) {

				Logger.log(ignore.getMessage(), ignore);

			}

			urlInputStream = null;

		}

	}

	protected Document createDocument(final String filePath)

			throws ParserConfigurationException, SAXException, IOException {

		DocumentBuilderFactory domFactory = DocumentBuilderFactory

				.newInstance();

		domFactory.setNamespaceAware(true);

		domFactory.setValidating(false);

		DocumentBuilder builder = domFactory.newDocumentBuilder();

		ErrorHandler errorHandler = new ErrorHandler() {

			public void error(SAXParseException exception)

					throws SAXParseException {

				throw exception;

			}

			public void fatalError(SAXParseException exception)

					throws SAXParseException {

				throw exception;

			}

			public void warning(SAXParseException exception)

					throws SAXParseException {

				throw exception;

			}

		};

		builder.setErrorHandler(errorHandler);

		Document doc = null;

		try {

			if (isUrl(filePath)) {

				if (urlInputStream != null) {

					doc = builder.parse(urlInputStream);

					closeInputStream();

				}

			} else {

				doc = builder.parse(filePath);

			}

		} catch (InvalidPathException e) {

			// This cannot happen as it has already been checked while the user

			// was typing in

		}

		return doc;

	}

	private String isFilePathValid(String filePath) {

		return isFileReadable(filePath);

	}

	/* (non-Javadoc)

	 * @see com.symbian.smt.gui.smtwidgets.IFileInputValidator#isFileReadable(java.lang.String)

	 */

	public String isFileReadable(String filePath) {

		String errorMessage = null;

		File inFile = new File(filePath);

		if (!inFile.canRead()) {

			return "Selected file cannot be read.";

		}

		return errorMessage;

	}

	/* (non-Javadoc)

	 * @see com.symbian.smt.gui.smtwidgets.IFileInputValidator#isUrl(java.lang.String)

	 */

	public boolean isUrl(String filePath) throws InvalidPathException {

		int index = filePath.indexOf(':');

		if (index == -1 || index == 1) {

			return false;

		} else if (index > 1) {

			return true;

		} else {

			throw new InvalidPathException("Unexpected file path format.");

		}

	}

	/* (non-Javadoc)

	 * @see com.symbian.smt.gui.smtwidgets.IFileInputValidator#isUrlResourceReadable(java.lang.String)

	 */

	public String isUrlResourceReadable(String filePath) {

		String errorMessage = null;

		try {

			URL fileURL = new URL(filePath.trim());

			URLConnection connection = fileURL.openConnection();

			String contentType = connection.getContentType();

			if (contentType == null) {

				return "System definition resource at specified URL cannot be read.";

			}

			if (!contentType.endsWith("xml")) {

				return "Specified URL is not an XML document.";

			}

			urlInputStream = connection.getInputStream();

			if (urlInputStream == null) {

				errorMessage = "System definition resource at specified URL cannot be read.";

			}

		} catch (IllegalArgumentException e) {

			closeInputStream();

			errorMessage = "System definition resource at specified URL cannot be read.";

		} catch (MalformedURLException e) {

			closeInputStream();

			errorMessage = "Specified URL is not a valid URL.";

		} catch (IOException e) {

			closeInputStream();

			errorMessage = "System definition resource at specified URL cannot be reached.";

		}

		return errorMessage;

	}

	private String isUrlValid(String url) {

		String errorMessage = null;

		try {

			URL inputUrl = new URL(url);

			inputUrl.openConnection();

		} catch (MalformedURLException e) {

			closeInputStream();

			errorMessage = "Specified URL is not a valid URL.";

		} catch (IOException e) {

			closeInputStream();

			errorMessage = "Resource at specified URL cannot be reached.";

		}

		return errorMessage;

	}

	/*

	 * @see org.eclipse.jface.dialogs.IInputValidator#isValid(java.lang.String)

	 */

	public String isValid(String filePath) {

		if (filePath == null || filePath.length() == 0) {

			return "";

		} else {

			return validateResourceWhileUserTypes(filePath);

		}

	}

	/* (non-Javadoc)

	 * @see com.symbian.smt.gui.smtwidgets.IXmlFileInputValidator#isXmlValid(java.lang.String)

	 */

	public String isXmlValid(String filePath) {

		return validateXml(filePath);

	}

	private String validateResourceWhileUserTypes(String filePath) {

		String errorMessage = null;

		// First check path is not UNC

		if (filePath.startsWith(File.separator)) {

			return "UNC paths are not compatible with the System Model Manager";

		}

		// Then check that filename (path) is not duplicate

		// by checking name against table

		if ((sysdefFilenames != null) && (sysdefFilenames.contains(filePath))) {

			return "The selected file has already been assigned.";

		}

		// Then check that path is appropriate

		try {

			if (isUrl(filePath)) {

				errorMessage = isUrlValid(filePath);

			} else {

				errorMessage = isFilePathValid(filePath);

			}

		} catch (InvalidPathException e) {

			errorMessage = e.getMessage();

		}

		return errorMessage;

	}

}