/*
 * Copyright 2002-2005 The Apache Software Foundation.
 * 
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 * 
 *      http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package com.rs.utils;

/**
 * <p>
 * Operations on Strings that contain words.
 * </p>
 * 
 * <p>
 * This class tries to handle <code>null</code> input gracefully. An exception will not be thrown for a <code>null</code>
 * input. Each method documents its behaviour in more detail.
 * </p>
 * 
 * @author Apache Jakarta Velocity
 * @author Henri Yandell
 * @author Stephen Colebourne
 * @author <a href="mailto:hps@intermeta.de">Henning P. Schmiedehausen</a>
 * @author Gary Gregory
 * @since 2.0
 * @version $Id: WordUtils.java 161678 2005-04-17 18:42:40Z mvdb $
 */
public class WordUtils {

	/**
	 * <p>
	 * <code>WordUtils</code> instances should NOT be constructed in standard programming. Instead, the class should be used as
	 * <code>WordUtils.wrap("foo bar", 20);</code>.
	 * </p>
	 *
	 * <p>
	 * This constructor is public to permit tools that require a JavaBean instance to operate.
	 * </p>
	 */
	public WordUtils() {
	}

	// Wrapping
	// --------------------------------------------------------------------------
	// /**
	// * <p>Wraps a block of text to a specified line length using '\n' as
	// * a newline.</p>
	// *
	// * <p>This method takes a block of text, which might have long lines in it
	// * and wraps the long lines based on the supplied lineLength parameter.</p>
	// *
	// * <p>If a single word is longer than the line length (eg. a URL), it will
	// * not be broken, and will display beyond the expected width.</p>
	// *
	// * <p>If there are tabs in inString, you are going to get results that are
	// * a bit strange. Tabs are a single character but are displayed as 4 or 8
	// * spaces. Remove the tabs.</p>
	// *
	// * @param str text which is in need of word-wrapping, may be null
	// * @param lineLength the column to wrap the words at
	// * @return the text with all the long lines word-wrapped
	// * <code>null</code> if null string input
	// */
	// public static String wrapText(String str, int lineLength) {
	// return wrap(str, null, lineLength);
	// }

	// /**
	// * <p>Wraps a block of text to a specified line length.</p>
	// *
	// * <p>This method takes a block of text, which might have long lines in it
	// * and wraps the long lines based on the supplied lineLength parameter.</p>
	// *
	// * <p>If a single word is longer than the wrapColumn (eg. a URL), it will
	// * not be broken, and will display beyond the expected width.</p>
	// *
	// * <p>If there are tabs in inString, you are going to get results that are
	// * a bit strange. Tabs are a single character but are displayed as 4 or 8
	// * spaces. Remove the tabs.</p>
	// *
	// * @param str text which is in need of word-wrapping, may be null
	// * @param newLineChars the characters that define a newline, null treated as \n
	// * @param lineLength the column to wrap the words at
	// * @return the text with all the long lines word-wrapped
	// * <code>null</code> if null string input
	// */
	// public static String wrapText(String str, String newLineChars, int lineLength) {
	// if (str == null) {
	// return null;
	// }
	// if (newLineChars == null) {
	// newLineChars = "\n";
	// }
	// StringTokenizer lineTokenizer = new StringTokenizer(str, newLineChars, true);
	// StringBuffer stringBuffer = new StringBuffer();
	//
	// while (lineTokenizer.hasMoreTokens()) {
	// try {
	// String nextLine = lineTokenizer.nextToken();
	//
	// if (nextLine.length() > lineLength) {
	// // This line is long enough to be wrapped.
	// nextLine = wrapLine(nextLine, null, lineLength, false);
	// }
	//
	// stringBuffer.append(nextLine);
	//
	// } catch (NoSuchElementException nsee) {
	// // thrown by nextToken(), but I don't know why it would
	// break;
	// }
	// }
	//
	// return stringBuffer.toString();
	// }

	// Wrapping
	// -----------------------------------------------------------------------
	/**
	 * <p>
	 * Wraps a single line of text, identifying words by <code>' '</code>.
	 * </p>
	 * 
	 * <p>
	 * New lines will be separated by the system property line separator. Very long words, such as URLs will <i>not</i> be
	 * wrapped.
	 * </p>
	 * 
	 * <p>
	 * Leading spaces on a new line are stripped. Trailing spaces are not stripped.
	 * </p>
	 *
	 * <pre>
	 * WordUtils.wrap(null, *) = null
	 * WordUtils.wrap("", *) = ""
	 * </pre>
	 *
	 * @param str the String to be word wrapped, may be null
	 * @param wrapLength the column to wrap the words at, less than 1 is treated as 1
	 * @return a line with newlines inserted, <code>null</code> if null input
	 */
	public static String wrap(String str, int wrapLength) {
		return wrap(str, wrapLength, null, false);
	}

	/**
	 * <p>
	 * Wraps a single line of text, identifying words by <code>' '</code>.
	 * </p>
	 * 
	 * <p>
	 * Leading spaces on a new line are stripped. Trailing spaces are not stripped.
	 * </p>
	 * 
	 * <pre>
	 * WordUtils.wrap(null, *, *, *) = null
	 * WordUtils.wrap("", *, *, *) = ""
	 * </pre>
	 *
	 * @param str the String to be word wrapped, may be null
	 * @param wrapLength the column to wrap the words at, less than 1 is treated as 1
	 * @param newLineStr the string to insert for a new line, <code>null</code> uses the system property line separator
	 * @param wrapLongWords true if long words (such as URLs) should be wrapped
	 * @return a line with newlines inserted, <code>null</code> if null input
	 */
	public static String wrap(String str, int wrapLength, String newLineStr, boolean wrapLongWords) {
		if (str == null) {
			return null;
		}
		if (newLineStr == null) {
			newLineStr = System.lineSeparator();
		}
		if (wrapLength < 1) {
			wrapLength = 1;
		}
		int inputLineLength = str.length();
		int offset = 0;
		StringBuffer wrappedLine = new StringBuffer(inputLineLength + 32);

		while ((inputLineLength - offset) > wrapLength) {
			if (str.charAt(offset) == ' ') {
				offset++;
				continue;
			}
			int spaceToWrapAt = str.lastIndexOf(' ', wrapLength + offset);

			if (spaceToWrapAt >= offset) {
				// normal case
				wrappedLine.append(str.substring(offset, spaceToWrapAt));
				wrappedLine.append(newLineStr);
				offset = spaceToWrapAt + 1;

			} else {
				// really long word or URL
				if (wrapLongWords) {
					// wrap really long word one line at a time
					wrappedLine.append(str.substring(offset, wrapLength + offset));
					wrappedLine.append(newLineStr);
					offset += wrapLength;
				} else {
					// do not wrap really long word, just extend beyond limit
					spaceToWrapAt = str.indexOf(' ', wrapLength + offset);
					if (spaceToWrapAt >= 0) {
						wrappedLine.append(str.substring(offset, spaceToWrapAt));
						wrappedLine.append(newLineStr);
						offset = spaceToWrapAt + 1;
					} else {
						wrappedLine.append(str.substring(offset));
						offset = inputLineLength;
					}
				}
			}
		}

		// Whatever is left in line is short enough to just pass through
		wrappedLine.append(str.substring(offset));

		return wrappedLine.toString();
	}

	// Capitalizing
	// -----------------------------------------------------------------------
	/**
	 * <p>
	 * Capitalizes all the whitespace separated words in a String. Only the first letter of each word is changed. To convert the
	 * rest of each word to lowercase at the same time, use {@link #capitalizeFully(String)}.
	 * </p>
	 *
	 * <p>
	 * Whitespace is defined by {@link Character#isWhitespace(char)}. A <code>null</code> input String returns <code>null</code>.
	 * Capitalization uses the unicode title case, normally equivalent to upper case.
	 * </p>
	 *
	 * <pre>
	 * WordUtils.capitalize(null)        = null
	 * WordUtils.capitalize("")          = ""
	 * WordUtils.capitalize("i am FINE") = "I Am FINE"
	 * </pre>
	 * 
	 * @param str the String to capitalize, may be null
	 * @return capitalized String, <code>null</code> if null String input
	 * @see #uncapitalize(String)
	 * @see #capitalizeFully(String)
	 */
	public static String capitalize(String str) {
		return capitalize(str, null);
	}

	/**
	 * <p>
	 * Capitalizes all the delimiter separated words in a String. Only the first letter of each word is changed. To convert the
	 * rest of each word to lowercase at the same time, use {@link #capitalizeFully(String, char[])}.
	 * </p>
	 *
	 * <p>
	 * The delimiters represent a set of characters understood to separate words. The first string character and the first
	 * non-delimiter character after a delimiter will be capitalized.
	 * </p>
	 *
	 * <p>
	 * A <code>null</code> input String returns <code>null</code>. Capitalization uses the unicode title case, normally
	 * equivalent to upper case.
	 * </p>
	 *
	 * <pre>
	 * WordUtils.capitalize(null, *)            = null
	 * WordUtils.capitalize("", *)              = ""
	 * WordUtils.capitalize(*, new char[0])     = *
	 * WordUtils.capitalize("i am fine", null)  = "I Am Fine"
	 * WordUtils.capitalize("i aM.fine", {'.'}) = "I aM.Fine"
	 * </pre>
	 * 
	 * @param str the String to capitalize, may be null
	 * @param delimiters set of characters to determine capitalization, null means whitespace
	 * @return capitalized String, <code>null</code> if null String input
	 * @see #uncapitalize(String)
	 * @see #capitalizeFully(String)
	 * @since 2.1
	 */
	public static String capitalize(String str, char[] delimiters) {
		if (str == null || str.length() == 0) {
			return str;
		}
		int strLen = str.length();
		StringBuffer buffer = new StringBuffer(strLen);

		int delimitersLen = 0;
		if (delimiters != null) {
			delimitersLen = delimiters.length;
		}

		boolean capitalizeNext = true;
		for (int i = 0; i < strLen; i++) {
			char ch = str.charAt(i);

			boolean isDelimiter = false;
			if (delimiters == null) {
				isDelimiter = Character.isWhitespace(ch);
			} else {
				for (int j = 0; j < delimitersLen; j++) {
					if (ch == delimiters[j]) {
						isDelimiter = true;
						break;
					}
				}
			}

			if (isDelimiter) {
				buffer.append(ch);
				capitalizeNext = true;
			} else if (capitalizeNext) {
				buffer.append(Character.toTitleCase(ch));
				capitalizeNext = false;
			} else {
				buffer.append(ch);
			}
		}
		return buffer.toString();
	}

	/**
	 * <p>
	 * Converts all the whitespace separated words in a String into capitalized words, that is each word is made up of a
	 * titlecase character and then a series of lowercase characters.
	 * </p>
	 *
	 * <p>
	 * Whitespace is defined by {@link Character#isWhitespace(char)}. A <code>null</code> input String returns <code>null</code>.
	 * Capitalization uses the unicode title case, normally equivalent to upper case.
	 * </p>
	 *
	 * <pre>
	 * WordUtils.capitalizeFully(null)        = null
	 * WordUtils.capitalizeFully("")          = ""
	 * WordUtils.capitalizeFully("i am FINE") = "I Am Fine"
	 * </pre>
	 * 
	 * @param str the String to capitalize, may be null
	 * @return capitalized String, <code>null</code> if null String input
	 */
	public static String capitalizeFully(String str) {
		return capitalizeFully(str, null);
	}

	/**
	 * <p>
	 * Converts all the delimiter separated words in a String into capitalized words, that is each word is made up of a titlecase
	 * character and then a series of lowercase characters.
	 * </p>
	 *
	 * <p>
	 * The delimiters represent a set of characters understood to separate words. The first string character and the first
	 * non-delimiter character after a delimiter will be capitalized.
	 * </p>
	 *
	 * <p>
	 * A <code>null</code> input String returns <code>null</code>. Capitalization uses the unicode title case, normally
	 * equivalent to upper case.
	 * </p>
	 *
	 * <pre>
	 * WordUtils.capitalizeFully(null, *)            = null
	 * WordUtils.capitalizeFully("", *)              = ""
	 * WordUtils.capitalizeFully(*, null)            = *
	 * WordUtils.capitalizeFully(*, new char[0])     = *
	 * WordUtils.capitalizeFully("i aM.fine", {'.'}) = "I am.Fine"
	 * </pre>
	 * 
	 * @param str the String to capitalize, may be null
	 * @param delimiters set of characters to determine capitalization, null means whitespace
	 * @return capitalized String, <code>null</code> if null String input
	 * @since 2.1
	 */
	public static String capitalizeFully(String str, char[] delimiters) {
		if (str == null || str.length() == 0) {
			return str;
		}
		str = str.toLowerCase();
		return capitalize(str, delimiters);
	}

	/**
	 * <p>
	 * Uncapitalizes all the whitespace separated words in a String. Only the first letter of each word is changed.
	 * </p>
	 *
	 * <p>
	 * Whitespace is defined by {@link Character#isWhitespace(char)}. A <code>null</code> input String returns <code>null</code>.
	 * </p>
	 *
	 * <pre>
	 * WordUtils.uncapitalize(null)        = null
	 * WordUtils.uncapitalize("")          = ""
	 * WordUtils.uncapitalize("I Am FINE") = "i am fINE"
	 * </pre>
	 * 
	 * @param str the String to uncapitalize, may be null
	 * @return uncapitalized String, <code>null</code> if null String input
	 * @see #capitalize(String)
	 */
	public static String uncapitalize(String str) {
		return uncapitalize(str, null);
	}

	/**
	 * <p>
	 * Uncapitalizes all the whitespace separated words in a String. Only the first letter of each word is changed.
	 * </p>
	 *
	 * <p>
	 * The delimiters represent a set of characters understood to separate words. The first string character and the first
	 * non-delimiter character after a delimiter will be uncapitalized.
	 * </p>
	 *
	 * <p>
	 * Whitespace is defined by {@link Character#isWhitespace(char)}. A <code>null</code> input String returns <code>null</code>.
	 * </p>
	 *
	 * <pre>
	 * WordUtils.uncapitalize(null, *)            = null
	 * WordUtils.uncapitalize("", *)              = ""
	 * WordUtils.uncapitalize(*, null)            = *
	 * WordUtils.uncapitalize(*, new char[0])     = *
	 * WordUtils.uncapitalize("I AM.FINE", {'.'}) = "i AM.fINE"
	 * </pre>
	 * 
	 * @param str the String to uncapitalize, may be null
	 * @param delimiters set of characters to determine uncapitalization, null means whitespace
	 * @return uncapitalized String, <code>null</code> if null String input
	 * @see #capitalize(String)
	 * @since 2.1
	 */
	public static String uncapitalize(String str, char[] delimiters) {
		if (str == null || str.length() == 0) {
			return str;
		}
		int strLen = str.length();

		int delimitersLen = 0;
		if (delimiters != null) {
			delimitersLen = delimiters.length;
		}

		StringBuffer buffer = new StringBuffer(strLen);
		boolean uncapitalizeNext = true;
		for (int i = 0; i < strLen; i++) {
			char ch = str.charAt(i);

			boolean isDelimiter = false;
			if (delimiters == null) {
				isDelimiter = Character.isWhitespace(ch);
			} else {
				for (int j = 0; j < delimitersLen; j++) {
					if (ch == delimiters[j]) {
						isDelimiter = true;
						break;
					}
				}
			}

			if (isDelimiter) {
				buffer.append(ch);
				uncapitalizeNext = true;
			} else if (uncapitalizeNext) {
				buffer.append(Character.toLowerCase(ch));
				uncapitalizeNext = false;
			} else {
				buffer.append(ch);
			}
		}
		return buffer.toString();
	}

	/**
	 * <p>
	 * Swaps the case of a String using a word based algorithm.
	 * </p>
	 * 
	 * <ul>
	 * <li>Upper case character converts to Lower case</li>
	 * <li>Title case character converts to Lower case</li>
	 * <li>Lower case character after Whitespace or at start converts to Title case</li>
	 * <li>Other Lower case character converts to Upper case</li>
	 * </ul>
	 * 
	 * <p>
	 * Whitespace is defined by {@link Character#isWhitespace(char)}. A <code>null</code> input String returns <code>null</code>.
	 * </p>
	 * 
	 * <pre>
	 * StringUtils.swapCase(null)                 = null
	 * StringUtils.swapCase("")                   = ""
	 * StringUtils.swapCase("The dog has a BONE") = "tHE DOG HAS A bone"
	 * </pre>
	 * 
	 * @param str the String to swap case, may be null
	 * @return the changed String, <code>null</code> if null String input
	 */
	public static String swapCase(String str) {
		int strLen;
		if (str == null || (strLen = str.length()) == 0) {
			return str;
		}
		StringBuffer buffer = new StringBuffer(strLen);

		boolean whitespace = true;
		char ch = 0;
		char tmp = 0;

		for (int i = 0; i < strLen; i++) {
			ch = str.charAt(i);
			if (Character.isUpperCase(ch)) {
				tmp = Character.toLowerCase(ch);
			} else if (Character.isTitleCase(ch)) {
				tmp = Character.toLowerCase(ch);
			} else if (Character.isLowerCase(ch)) {
				if (whitespace) {
					tmp = Character.toTitleCase(ch);
				} else {
					tmp = Character.toUpperCase(ch);
				}
			} else {
				tmp = ch;
			}
			buffer.append(tmp);
			whitespace = Character.isWhitespace(ch);
		}
		return buffer.toString();
	}

}