content: /*******************************************************************************
   * Copyright (c) 2000, 2008 IBM Corporation and others.
   * 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
   *
   * Contributors:
   *     IBM Corporation - initial API and implementation
   *******************************************************************************/
  package org.eclipse.wst.jsdt.internal.corext.util;
  
  import org.eclipse.core.runtime.Assert;
  import org.eclipse.jface.action.LegacyActionTools;
  import org.eclipse.jface.text.BadLocationException;
  import org.eclipse.jface.text.DefaultLineTracker;
  import org.eclipse.jface.text.ILineTracker;
  import org.eclipse.jface.text.IRegion;
  import org.eclipse.wst.jsdt.core.IJavaScriptProject;
  import org.eclipse.wst.jsdt.core.formatter.IndentManipulation;
  
  
  /**
   * Helper class to provide String manipulation functions not available in standard JDK.
   */
  public class Strings {
  	
  	private Strings(){}
  	
  	/**
  	 * tests if a char is lower case. Fix for 26529 
  	 */
  	public static boolean isLowerCase(char ch) {
  		return Character.toLowerCase(ch) == ch;
  	}	
  	
  	public static boolean startsWithIgnoreCase(String text, String prefix) {
  		int textLength= text.length();
  		int prefixLength= prefix.length();
  		if (textLength < prefixLength)
  			return false;
  		for (int i= prefixLength - 1; i >= 0; i--) {
  			if (Character.toLowerCase(prefix.charAt(i)) != Character.toLowerCase(text.charAt(i)))
  				return false;
  		}
  		return true;
  	}
  
  	public static String removeNewLine(String message) {
  		StringBuffer result= new StringBuffer();
  		int current= 0;
  		int index= message.indexOf('\n', 0);
  		while (index != -1) {
  			result.append(message.substring(current, index));
  			if (current < index && index != 0)
  				result.append(' ');
  			current= index + 1;
  			index= message.indexOf('\n', current);
  		}
  		result.append(message.substring(current));
  		return result.toString();
  	}
  
  	/**
  	 * Converts the given string into an array of lines. The lines 
  	 * don't contain any line delimiter characters.
  	 *
  	 * @return the string converted into an array of strings. Returns <code>
  	 * 	null</code> if the input string can't be converted in an array of lines.
  	 */
  	public static String[] convertIntoLines(String input) {
  		try {
  			ILineTracker tracker= new DefaultLineTracker();
  			tracker.set(input);
  			int size= tracker.getNumberOfLines();
  			String result[]= new String[size];
  			for (int i= 0; i < size; i++) {
  				IRegion region= tracker.getLineInformation(i);
  				int offset= region.getOffset();
  				result[i]= input.substring(offset, offset + region.getLength());
  			}
  			return result;
  		} catch (BadLocationException e) {
  			return null;
  		}
  	}
  
  	/**
  	 * Returns <code>true</code> if the given string only consists of
  	 * white spaces according to Java. If the string is empty, <code>true
  	 * </code> is returned.
  	 * 
  	 * @return <code>true</code> if the string only consists of white
  	 * 	spaces; otherwise <code>false</code> is returned
  	 * 
  	 * @see java.lang.Character#isWhitespace(char)
  	 */
  	public static boolean containsOnlyWhitespaces(String s) {
  		int size= s.length();
  		for (int i= 0; i < size; i++) {
  			if (!Character.isWhitespace(s.charAt(i)))
  				return false;
  		}
  		return true;
  	}
  	
  	/**
  	 * Removes leading tabs and spaces from the given string. If the string
  	 * doesn't contain any leading tabs or spaces then the string itself is 
  	 * returned.
  	 */
  	public static String trimLeadingTabsAndSpaces(String line) {
  		int size= line.length();
  		int start= size;
  		for (int i= 0; i < size; i++) {
  			char c= line.charAt(i);
  			if (!IndentManipulation.isIndentChar(c)) {
  				start= i;
  				break;
  			}
  		}
  		if (start == 0)
  			return line;
  		else if (start == size)
  			return ""; //$NON-NLS-1$
  		else
  			return line.substring(start);
  	}
  	
  	public static String trimTrailingTabsAndSpaces(String line) {
  		int size= line.length();
  		int end= size;
  		for (int i= size - 1; i >= 0; i--) {
  			char c= line.charAt(i);
  			if (IndentManipulation.isIndentChar(c)) {
  				end= i;
  			} else {
  				break;
  			}
  		}
  		if (end == size)
  			return line;
  		else if (end == 0)
  			return ""; //$NON-NLS-1$
  		else
  			return line.substring(0, end);
  	}
  		
  	/**
  	 * Returns the indent of the given string in indentation units. Odd spaces
  	 * are not counted.
  	 * 
  	 * @param line the text line
  	 * @param project the java project from which to get the formatter
  	 *        preferences, or <code>null</code> for global preferences
  	 * 
  	 */
  	public static int computeIndentUnits(String line, IJavaScriptProject project) {
  		return IndentManipulation.measureIndentUnits(line, CodeFormatterUtil.getTabWidth(project), CodeFormatterUtil.getIndentWidth(project));
  	}
  	
  	/**
  	 * Returns the indent of the given string in indentation units. Odd spaces
  	 * are not counted.
  	 * 
  	 * @param line the text line
  	 * @param tabWidth the width of the '\t' character in space equivalents
  	 * @param indentWidth the width of one indentation unit in space equivalents
  	 * 
  	 */
  	public static int computeIndentUnits(String line, int tabWidth, int indentWidth) {
  		return IndentManipulation.measureIndentUnits(line, tabWidth, indentWidth);
  	}
  	
  	/**
  	 * Computes the visual length of the indentation of a
  	 * <code>CharSequence</code>, counting a tab character as the size until
  	 * the next tab stop and every other whitespace character as one.
  	 * 
  	 * @param line the string to measure the indent of
  	 * @param tabSize the visual size of a tab in space equivalents
  	 * @return the visual length of the indentation of <code>line</code>
  	 * 
  	 */
  	public static int measureIndentLength(CharSequence line, int tabSize) {
  		return IndentManipulation.measureIndentInSpaces(line, tabSize);
  	}
  
  	/**
  	 * Removes the given number of indents from the line. Asserts that the given line 
  	 * has the requested number of indents. If <code>indentsToRemove <= 0</code>
  	 * the line is returned.
  	 * 
  	 * @param project the java project from which to get the formatter
  	 *        preferences, or <code>null</code> for global preferences
  	 * 
  	 */
  	public static String trimIndent(String line, int indentsToRemove, IJavaScriptProject project) {
  		return IndentManipulation.trimIndent(line, indentsToRemove, CodeFormatterUtil.getTabWidth(project), CodeFormatterUtil.getIndentWidth(project));
  	}
  	
  	/**
  	 * Removes the given number of indents from the line. Asserts that the given line 
  	 * has the requested number of indents. If <code>indentsToRemove <= 0</code>
  	 * the line is returned.
  	 * 
  	 * 
  	 */
  	public static String trimIndent(String line, int indentsToRemove, int tabWidth, int indentWidth) {
  		return IndentManipulation.trimIndent(line, indentsToRemove, tabWidth, indentWidth);
  	}
  	
  	/**
  	 * Removes the common number of indents from all lines. If a line
  	 * only consists out of white space it is ignored.
  
  	 * @param project the java project from which to get the formatter
  	 *        preferences, or <code>null</code> for global preferences
  	 * 
  	 */
  	public static void trimIndentation(String[] lines, IJavaScriptProject project) {
  		trimIndentation(lines, CodeFormatterUtil.getTabWidth(project), CodeFormatterUtil.getIndentWidth(project), true);
  	}
  	/**
  	 * Removes the common number of indents from all lines. If a line
  	 * only consists out of white space it is ignored.
  	 * 
  	 * 
  	 */
  	public static void trimIndentation(String[] lines, int tabWidth, int indentWidth) {
  		trimIndentation(lines, tabWidth, indentWidth, true);
  	}
  	
  	/**
  	 * Removes the common number of indents from all lines. If a line
  	 * only consists out of white space it is ignored. If <code>
  	 * considerFirstLine</code> is false the first line will be ignored.
  	 * 
  	 * @param project the java project from which to get the formatter
  	 *        preferences, or <code>null</code> for global preferences
  	 * 
  	 */
  	public static void trimIndentation(String[] lines, IJavaScriptProject project, boolean considerFirstLine) {
  		trimIndentation(lines, CodeFormatterUtil.getTabWidth(project), CodeFormatterUtil.getIndentWidth(project), considerFirstLine);
  	}
  	
  	/**
  	 * Removes the common number of indents from all lines. If a line
  	 * only consists out of white space it is ignored. If <code>
  	 * considerFirstLine</code> is false the first line will be ignored.
  	 * 
  	 */
  	public static void trimIndentation(String[] lines, int tabWidth, int indentWidth, boolean considerFirstLine) {
  		String[] toDo= new String[lines.length];
  		// find indentation common to all lines
  		int minIndent= Integer.MAX_VALUE; // very large
  		for (int i= considerFirstLine ? 0 : 1; i < lines.length; i++) {
  			String line= lines[i];
  			if (containsOnlyWhitespaces(line))
  				continue;
  			toDo[i]= line;
  			int indent= computeIndentUnits(line, tabWidth, indentWidth);
  			if (indent < minIndent) {
  				minIndent= indent;
  			}
  		}
  		
  		if (minIndent > 0) {
  			// remove this indent from all lines
  			for (int i= considerFirstLine ? 0 : 1; i < toDo.length; i++) {
  				String s= toDo[i];
  				if (s != null)
  					lines[i]= trimIndent(s, minIndent, tabWidth, indentWidth);
  				else {
  					String line= lines[i];
  					int indent= computeIndentUnits(line, tabWidth, indentWidth);
  					if (indent > minIndent)
  						lines[i]= trimIndent(line, minIndent, tabWidth, indentWidth);
  					else
  						lines[i]= trimLeadingTabsAndSpaces(line);
  				}
  			}
  		}
  	}
  		
  	/**
  	 * Returns that part of the indentation of <code>line</code> that makes up
  	 * a multiple of indentation units.
  	 * 
  	 * @param line the line to scan
  	 * @param project the java project from which to get the formatter
  	 *        preferences, or <code>null</code> for global preferences
  	 * @return the indent part of <code>line</code>, but no odd spaces
  	 * 
  	 */
  	public static String getIndentString(String line, IJavaScriptProject project) {
  		return IndentManipulation.extractIndentString(line, CodeFormatterUtil.getTabWidth(project), CodeFormatterUtil.getIndentWidth(project));
  	}
  	
  	/**
  	 * Returns that part of the indentation of <code>line</code> that makes up
  	 * a multiple of indentation units.
  	 * 
  	 * @param line the line to scan
  	 * @param tabWidth the size of one tab in space equivalents
  	 * @param indentWidth the size of the indent in space equivalents
  	 * @return the indent part of <code>line</code>, but no odd spaces
  	 * 
  	 */
  	public static String getIndentString(String line, int tabWidth, int indentWidth) {
  		return IndentManipulation.extractIndentString(line, tabWidth, indentWidth);
  	}
  		
  	public static String[] removeTrailingEmptyLines(String[] sourceLines) {
  		int lastNonEmpty= findLastNonEmptyLineIndex(sourceLines);
  		String[] result= new String[lastNonEmpty + 1];
  		for (int i= 0; i < result.length; i++) {
  			result[i]= sourceLines[i];
  		}
  		return result;
  	}
  
  	private static int findLastNonEmptyLineIndex(String[] sourceLines) {
  		for (int i= sourceLines.length - 1; i >= 0; i--) {
  			if (! sourceLines[i].trim().equals(""))//$NON-NLS-1$
  				return i;
  		}
  		return -1;
  	}
  	
  	/**
  	 * Change the indent of, possible muti-line, code range. The current indent is removed, a new indent added.
  	 * The first line of the code will not be changed. (It is considered to have no indent as it might start in
  	 * the middle of a line)
  	 * 
  	 * @param project the java project from which to get the formatter
  	 *        preferences, or <code>null</code> for global preferences
  	 * 
  	 */
  	public static String changeIndent(String code, int codeIndentLevel, IJavaScriptProject project, String newIndent, String lineDelim) {
  		return IndentManipulation.changeIndent(code, codeIndentLevel, CodeFormatterUtil.getTabWidth(project), CodeFormatterUtil.getIndentWidth(project), newIndent, lineDelim);
  	}
  	
  	/**
  	 * Change the indent of, possible muti-line, code range. The current indent is removed, a new indent added.
  	 * The first line of the code will not be changed. (It is considered to have no indent as it might start in
  	 * the middle of a line)
  	 * 
  	 */
  	public static String changeIndent(String code, int codeIndentLevel, int tabWidth, int indentWidth, String newIndent, String lineDelim) {
  		return IndentManipulation.changeIndent(code, codeIndentLevel, tabWidth, indentWidth, newIndent, lineDelim);
  	}
  	
  	public static String trimIndentation(String source, IJavaScriptProject project, boolean considerFirstLine) {
  		return trimIndentation(source, CodeFormatterUtil.getTabWidth(project), CodeFormatterUtil.getIndentWidth(project), considerFirstLine);
  	}
  	
  	public static String trimIndentation(String source, int tabWidth, int indentWidth, boolean considerFirstLine) {
  		try {
  			ILineTracker tracker= new DefaultLineTracker();
  			tracker.set(source);
  			int size= tracker.getNumberOfLines();
  			if (size == 1)
  				return source;
  			String lines[]= new String[size];
  			for (int i= 0; i < size; i++) {
  				IRegion region= tracker.getLineInformation(i);
  				int offset= region.getOffset();
  				lines[i]= source.substring(offset, offset + region.getLength());
  			}
  			Strings.trimIndentation(lines, tabWidth, indentWidth, considerFirstLine);
  			StringBuffer result= new StringBuffer();
  			int last= size - 1;
  			for (int i= 0; i < size; i++) {
  				result.append(lines[i]);
  				if (i < last)
  					result.append(tracker.getLineDelimiter(i));
  			}
  			return result.toString();
  		} catch (BadLocationException e) {
  			Assert.isTrue(false,"Can not happend"); //$NON-NLS-1$
  			return null;
  		}
  	}
  		
  	
  	/**
  	 * Concatenate the given strings into one strings using the passed line delimiter as a
  	 * delimiter. No delimiter is added to the last line.
  	 */
  	public static String concatenate(String[] lines, String delimiter) {
  		StringBuffer buffer= new StringBuffer();
  		for (int i= 0; i < lines.length; i++) {
  			if (i > 0)
  				buffer.append(delimiter);
  			buffer.append(lines[i]);
  		}
  		return buffer.toString();
  	}
  	
  	public static boolean equals(String s, char[] c) {
  		if (s.length() != c.length)
  			return false;
  
  		for (int i = c.length; --i >= 0;)
  			if (s.charAt(i) != c[i])
  				return false;
  		return true;
  	}
  		
  	public static String removeTrailingCharacters(String text, char toRemove) {
  		int size= text.length();
  		int end= size;
  		for (int i= size - 1; i >= 0; i--) {
  			char c= text.charAt(i);
  			if (c == toRemove) {
  				end= i;
  			} else {
  				break;
  			}
  		}
  		if (end == size)
  			return text;
  		else if (end == 0)
  			return ""; //$NON-NLS-1$
  		else
  			return text.substring(0, end);
  	}
  	
  	public static String removeMnemonicIndicator(String string) {
  		return LegacyActionTools.removeMnemonics(string);
  	}
  }
  