/*

* Copyright (c) 2008 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:

*

*/

package com.nokia.s60tools.util.resource;

import java.io.BufferedInputStream;

import java.io.BufferedWriter;

import java.io.File;

import java.io.FileInputStream;

import java.io.FileNotFoundException;

import java.io.FileOutputStream;

import java.io.FileWriter;

import java.io.IOException;

import java.io.OutputStreamWriter;

import org.eclipse.core.resources.IFile;

import org.eclipse.core.resources.IProject;

import org.eclipse.core.resources.IResource;

import org.eclipse.core.resources.IWorkspace;

import org.eclipse.core.resources.ResourcesPlugin;

import org.eclipse.core.runtime.CoreException;

import org.eclipse.core.runtime.IPath;

import org.eclipse.core.runtime.Path;

import org.eclipse.swt.SWT;

import org.eclipse.swt.widgets.FileDialog;

import org.eclipse.swt.widgets.Shell;

import org.eclipse.ui.IEditorDescriptor;

import org.eclipse.ui.IWorkbench;

import org.eclipse.ui.IWorkbenchPage;

import org.eclipse.ui.IWorkbenchWindow;

import org.eclipse.ui.PartInitException;

import org.eclipse.ui.PlatformUI;

import org.eclipse.ui.part.FileEditorInput;

import com.nokia.s60tools.util.internal.Messages;

/**

 * Miscellaneous utility methods related to files.

 */

public class FileUtils {

	/**

	 * Constant for UTF-8 encoding type.

	 */

	public static final String ENCODING_TYPE_UTF_8 = "UTF-8"; //$NON-NLS-1$

	/**

	 * Constant for UTF-8 encoding type.

	 */

	public static final String ENCODING_TYPE_UTF_16 = "UTF-16"; //$NON-NLS-1$

	/**

	 * Queries user for an external file to be opened, and opens it.

	 * @param projectName Name of the project to open file into.

	 * @throws CoreException

	 * @throws PartInitException

	 * @throws FileNotFoundException 

	 */

	public static void openExternalFileDialog(String projectName) throws CoreException, PartInitException, FileNotFoundException {

	   IWorkbench workbench = PlatformUI.getWorkbench();			   

	   IWorkbenchWindow window = workbench.getActiveWorkbenchWindow();

	   Shell shell = window.getShell();

	   String fileAbsolutePathName = new FileDialog(shell, SWT.OPEN).open();

	   if (fileAbsolutePathName == null)

	      return;

	   openExternalFileImpl(fileAbsolutePathName, workbench, projectName);

	}

	/**

	 * Opens the external file given as parameter.

	 * @param fileAbsolutePathName Absolute path name to the file to be opened.

	 * @param projectName Name of the project to open file into.

	 * @throws CoreException

	 * @throws PartInitException

	 * @throws FileNotFoundException 

	 */

	public static void openExternalFile(String fileAbsolutePathName, String projectName) throws CoreException, PartInitException, FileNotFoundException {		

	   IWorkbench workbench = PlatformUI.getWorkbench();			   

	   openExternalFileImpl(fileAbsolutePathName, workbench, projectName);

	}

	/**

	 * Opens the external file given as parameter.

	 * @param fileAbsolutePathName Absolute path name to the file to be opened.

	 * @param workbench Workbench to be used.

	 * @param projectName Name of the project to open file into.

	 * @throws CoreException

	 * @throws PartInitException

	 * @throws FileNotFoundException 

	 */

	private static void openExternalFileImpl(String fileAbsolutePathName, IWorkbench workbench, String projectName) throws CoreException, PartInitException, FileNotFoundException {

		File f = new File(fileAbsolutePathName);

		if(!f.exists()){

			throw new FileNotFoundException(Messages.getString("FileUtils.NonExistingExternalFile_ErrMsg") + fileAbsolutePathName); //$NON-NLS-1$

		}

	   IPath location = new Path(fileAbsolutePathName);		   		   

	   IWorkspace ws = ResourcesPlugin.getWorkspace();

	   IProject project = ws.getRoot().getProject(projectName); //$NON-NLS-1$

	   if (!project.exists())

	      project.create(null);

	   if (!project.isOpen())

	      project.open(null);

	   IFile file = project.getFile(location.lastSegment());

	   file.createLink(location, IResource.REPLACE, null);

	   final FileEditorInput editorInput = new FileEditorInput(file);

	   IWorkbenchWindow window = workbench.getActiveWorkbenchWindow();	

	   IWorkbenchPage page = window.getActivePage();

	   if (page != null){

		   IEditorDescriptor desc = workbench.getEditorRegistry().getDefaultEditor(file.getName());

		   page.openEditor(editorInput, desc.getId());

	   }

	}

	/**

	 * Loads the contents of the given file into memory. 

	 * @param filePathName Absolute path name for the file.

	 * @return StringBuffer instance having the contents of the file.

	 * @throws FileNotFoundException

	 * @throws IOException

	 */

	public static StringBuffer loadDataFromFile(String filePathName) throws FileNotFoundException, IOException {

		StringBuffer dataBuffer = new StringBuffer();

		File f = new File(filePathName);

		FileInputStream fis = new FileInputStream(f);

		BufferedInputStream br = new BufferedInputStream(fis);

		int available = fis.available();

		for(int readLoopCount=1; available > 0;readLoopCount++){

			byte[] tmpByteArr = new byte[available];

			int readBytes = br.read(tmpByteArr, 0, available);

			if(readBytes == -1){

				break;

			}

			else if(readBytes != available){

				br.close();

				fis.close();

				throw new IOException(Messages.getString("FileUtils.FAILED_TO_LOAD_DATA")  //$NON-NLS-1$

						              + filePathName 

						              + Messages.getString("FileUtils.LESS_BYTES_THAN_EXPECTED")); //$NON-NLS-1$

			}

			dataBuffer.append(new String(tmpByteArr, 0, readBytes));

			available = fis.available();

		}

		br.close();

		fis.close();

		return dataBuffer;

	}

	/**

	 * Save text to file. If the folder where file is located does not exist, creating one.

	 * @param filename file name with full path

	 * @param file file contents

	 * @throws IOException

	 */

	public static void writeToFile( String fileName, String fileContents ) throws IOException {		

		writeToFile(fileName, fileContents, null);

	}		

	/**

	 * Save text to file. If the folder where file is located does not exist, creating one.

	 * Sets file encoding type.

	 * @param filename file name with full path

	 * @param file file contents

	 * @param encoding encoding type e.g. {@link FileUtils.ENCODING_TYPE_UTF_8}  

	 * @throws IOException

	 */

	public static void writeToFile( String fileName, String fileContents, String encoding ) throws IOException {		

		BufferedWriter out = null;

		try {

			File file = new File(fileName);

			File parent = file.getParentFile();

			if(!parent.exists()){

				parent.mkdirs();

			}

			//If encoding is set

			if(encoding != null){

				out = new BufferedWriter(new OutputStreamWriter(new FileOutputStream(fileName), encoding));

			}

			else{

				out = new BufferedWriter(new FileWriter(fileName));

			}

			out.write(fileContents);			

		} catch (IOException e) {

			e.printStackTrace();

			throw e;

		}finally{

			if(out != null){

				out.close();				

			}

		}

	}	

	/**

	 * Gets logical drive for the given file object pointing to a file or path name.

	 * @param absolutePathNameFileObject File object containing a directory or a file path name..

	 * @return logical drive for the file or path name including colon and file separator (e.g. C:\)

	 */

	public static String getLogicalDrive(File absolutePathNameFileObject) {

		File parentFile = absolutePathNameFileObject;

		while(parentFile.getParentFile() != null){

			parentFile = parentFile.getParentFile();

		}

		return parentFile.getAbsolutePath();

	}

	/**

	 * Gets logical drive for the given file or path name string. The given path should be absolute.

	 * If given path is relative (i.e. does not contain logical drive in path name), a new file

	 * object is created which adds current directory with current logical drive before the relative path.

	 * @param absolutePathName Absolute path name string to a directory a file containing logical drive

	 * @return logical drive for the file or path name including colon and file separator (e.g. C:\)

	 */

	public static String getLogicalDrive(String absolutePathName) {

		return getLogicalDrive(new File(absolutePathName));

	}

	/**

	 * Checks if the given path starts with drive letter sequence e.g. with C:\ and contains

	 * at least a single character after the drive letter start sequence.

	 * Check is done with the following regular expression <code>[a-zA-Z]:[\\/].+</code> that 

	 * e.g. matches the following paths

	 * - A:\my\example\path1, c:\my\example\path1, Z:/my\example\path3, and r:/my/example/path1

	 * but does not match the following ones:

	 * - :\my\example\path2, \my\example\path, z:\, R:/ 

	 * If regular expression matches the first three letters are removed from the path.

	 * @param pathName Path name to check for drive letter removal. Path can be absolute

	 *                 or relative, and does not have point to valid file or directory. 

	 * @return Source path without drive letter, if it existed previously.

	 */

	public static String removeDriveLetterPortionFromPathIfExists(String pathName) {

		String pathWithDriveLetterRegExp = "[a-zA-Z]:[\\\\/].+"; //$NON-NLS-1$

		if(pathName.matches(pathWithDriveLetterRegExp)){

			// In case of match skipping first three letters

			return pathName.substring(3); 		

		}

		return pathName;

	}

  	/**

	 * Replaces all characters that cannot be used in Win32 directory and file names.

	 * @param stringToBeChecked string to be checked for illegal characters.

	 * @param replaceChar replacement character for illegal filename characters found

	 * @return string from which all illegal filename characters are replaced

	 */

	public static String removeIllegalWin32FilenameCharactersFromString(String stringToBeChecked, char replaceChar) {

		// Set of characters that cannot be part of a file or directory name (list was got from win32 error message) 

		final char illegalFilenameCharsArr[] = { '\\', '/', ':', '*', '?', '"', '<', '>', '|' };

		// Checking that replacement character itself is not illegal character

		if(new String(illegalFilenameCharsArr).indexOf(replaceChar) != -1){

			throw new IllegalArgumentException("Tried to replace illegal Win32 filename character with also illegal character" + ": " + replaceChar);

		}

		String resultString = new String(stringToBeChecked);

		if(resultString != null){

			for (int i = 0; i < illegalFilenameCharsArr.length; i++) {

				char ch = illegalFilenameCharsArr[i];				

				resultString = resultString.replace(ch, replaceChar);

			}		

		}

		return resultString;

	}

}