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YUI.add('text-wordbreak', function (Y, NAME) {

/**

 * Provides utility methods for splitting strings on word breaks and determining

 * whether a character index represents a word boundary.

 *

 * @module text

 * @submodule text-wordbreak

 */

/**

 * <p>

 * Provides utility methods for splitting strings on word breaks and determining

 * whether a character index represents a word boundary, using the generic word

 * breaking algorithm defined in the Unicode Text Segmentation guidelines

 * (<a href="http://unicode.org/reports/tr29/#Word_Boundaries">Unicode Standard

 * Annex #29</a>).

 * </p>

 *

 * <p>

 * This algorithm provides a reasonable default for many languages. However, it

 * does not cover language or context specific requirements, and it does not

 * provide meaningful results at all for languages that don't use spaces between

 * words, such as Chinese, Japanese, Thai, Lao, Khmer, and others. Server-based

 * word breaking services usually provide significantly better results with

 * better performance.

 * </p>

 *

 * @class Text.WordBreak

 * @static

 */

var Text   = Y.Text,

    WBData = Text.Data.WordBreak,

// Constants representing code point classifications.

ALETTER      = 0,

MIDNUMLET    = 1,

MIDLETTER    = 2,

MIDNUM       = 3,

NUMERIC      = 4,

CR           = 5,

LF           = 6,

NEWLINE      = 7,

EXTEND       = 8,

FORMAT       = 9,

KATAKANA     = 10,

EXTENDNUMLET = 11,

OTHER        = 12,

// RegExp objects generated from code point data. Each regex matches a single

// character against a set of Unicode code points. The index of each item in

// this array must match its corresponding code point constant value defined

// above.

SETS = [

    new RegExp(WBData.aletter),

    new RegExp(WBData.midnumlet),

    new RegExp(WBData.midletter),

    new RegExp(WBData.midnum),

    new RegExp(WBData.numeric),

    new RegExp(WBData.cr),

    new RegExp(WBData.lf),

    new RegExp(WBData.newline),

    new RegExp(WBData.extend),

    new RegExp(WBData.format),

    new RegExp(WBData.katakana),

    new RegExp(WBData.extendnumlet)

],

EMPTY_STRING = '',

PUNCTUATION  = new RegExp('^' + WBData.punctuation + '$'),

WHITESPACE   = /\s/,

WordBreak = {

    // -- Public Static Methods ------------------------------------------------

    /**

     * Splits the specified string into an array of individual words.

     *

     * @method getWords

     * @param {String} string String to split.

     * @param {Object} options (optional) Options object containing zero or more

     *   of the following properties:

     *

     * <dl>

     *   <dt>ignoreCase (Boolean)</dt>

     *   <dd>

     *     If <code>true</code>, the string will be converted to lowercase

     *     before being split. Default is <code>false</code>.

     *   </dd>

     *

     *   <dt>includePunctuation (Boolean)</dt>

     *   <dd>

     *     If <code>true</code>, the returned array will include punctuation

     *     characters. Default is <code>false</code>.

     *   </dd>

     *

     *   <dt>includeWhitespace (Boolean)</dt>

     *   <dd>

     *     If <code>true</code>, the returned array will include whitespace

     *     characters. Default is <code>false</code>.

     *   </dd>

     * </dl>

     * @return {Array} Array of words.

     * @static

     */

    getWords: function (string, options) {

        var i     = 0,

            map   = WordBreak._classify(string),

            len   = map.length,

            word  = [],

            words = [],

            chr,

            includePunctuation,

            includeWhitespace;

        if (!options) {

            options = {};

        }

        if (options.ignoreCase) {

            string = string.toLowerCase();

        }

        includePunctuation = options.includePunctuation;

        includeWhitespace  = options.includeWhitespace;

        // Loop through each character in the classification map and determine

        // whether it precedes a word boundary, building an array of distinct

        // words as we go.

        for (; i < len; ++i) {

            chr = string.charAt(i);

            // Append this character to the current word.

            word.push(chr);

            // If there's a word boundary between the current character and the

            // next character, append the current word to the words array and

            // start building a new word.

            if (WordBreak._isWordBoundary(map, i)) {

                word = word.join(EMPTY_STRING);

                if (word &&

                        (includeWhitespace  || !WHITESPACE.test(word)) &&

                        (includePunctuation || !PUNCTUATION.test(word))) {

                    words.push(word);

                }

                word = [];

            }

        }

        return words;

    },

    /**

     * Returns an array containing only unique words from the specified string.

     * For example, the string <code>'foo bar baz foo'</code> would result in

     * the array <code>['foo', 'bar', 'baz']</code>.

     *

     * @method getUniqueWords

     * @param {String} string String to split.

     * @param {Object} options (optional) Options (see <code>getWords()</code>

     *   for details).

     * @return {Array} Array of unique words.

     * @static

     */

    getUniqueWords: function (string, options) {

        return Y.Array.unique(WordBreak.getWords(string, options));

    },

    /**

     * <p>

     * Returns <code>true</code> if there is a word boundary between the

     * specified character index and the next character index (or the end of the

     * string).

     * </p>

     *

     * <p>

     * Note that there are always word breaks at the beginning and end of a

     * string, so <code>isWordBoundary('', 0)</code> and

     * <code>isWordBoundary('a', 0)</code> will both return <code>true</code>.

     * </p>

     *

     * @method isWordBoundary

     * @param {String} string String to test.

     * @param {Number} index Character index to test within the string.

     * @return {Boolean} <code>true</code> for a word boundary,

     *   <code>false</code> otherwise.

     * @static

     */

    isWordBoundary: function (string, index) {

        return WordBreak._isWordBoundary(WordBreak._classify(string), index);

    },

    // -- Protected Static Methods ---------------------------------------------

    /**

     * Returns a character classification map for the specified string.

     *

     * @method _classify

     * @param {String} string String to classify.

     * @return {Array} Classification map.

     * @protected

     * @static

     */

    _classify: function (string) {

        var chr,

            map          = [],

            i            = 0,

            j,

            set,

            stringLength = string.length,

            setsLength   = SETS.length,

            type;

        for (; i < stringLength; ++i) {

            chr  = string.charAt(i);

            type = OTHER;

            for (j = 0; j < setsLength; ++j) {

                set = SETS[j];

                if (set && set.test(chr)) {

                    type = j;

                    break;

                }

            }

            map.push(type);

        }

        return map;

    },

    /**

     * <p>

     * Returns <code>true</code> if there is a word boundary between the

     * specified character index and the next character index (or the end of the

     * string).

     * </p>

     *

     * <p>

     * Note that there are always word breaks at the beginning and end of a

     * string, so <code>_isWordBoundary('', 0)</code> and

     * <code>_isWordBoundary('a', 0)</code> will both return <code>true</code>.

     * </p>

     *

     * @method _isWordBoundary

     * @param {Array} map Character classification map generated by

     *   <code>_classify</code>.

     * @param {Number} index Character index to test.

     * @return {Boolean}

     * @protected

     * @static

     */

    _isWordBoundary: function (map, index) {

        var prevType,

            type     = map[index],

            nextType = map[index + 1],

            nextNextType;

        if (index < 0 || (index > map.length - 1 && index !== 0)) {

            Y.log('isWordBoundary: index out of bounds', 'warn', 'text-wordbreak');

            return false;

        }

        // WB5. Don't break between most letters.

        if (type === ALETTER && nextType === ALETTER) {

            return false;

        }

        nextNextType = map[index + 2];

        // WB6. Don't break letters across certain punctuation.

        if (type === ALETTER &&

                (nextType === MIDLETTER || nextType === MIDNUMLET) &&

                nextNextType === ALETTER) {

            return false;

        }

        prevType = map[index - 1];

        // WB7. Don't break letters across certain punctuation.

        if ((type === MIDLETTER || type === MIDNUMLET) &&

                nextType === ALETTER &&

                prevType === ALETTER) {

            return false;

        }

        // WB8/WB9/WB10. Don't break inside sequences of digits or digits

        // adjacent to letters.

        if ((type === NUMERIC || type === ALETTER) &&

                (nextType === NUMERIC || nextType === ALETTER)) {

            return false;

        }

        // WB11. Don't break inside numeric sequences like "3.2" or

        // "3,456.789".

        if ((type === MIDNUM || type === MIDNUMLET) &&

                nextType === NUMERIC &&

                prevType === NUMERIC) {

            return false;

        }

        // WB12. Don't break inside numeric sequences like "3.2" or

        // "3,456.789".

        if (type === NUMERIC &&

                (nextType === MIDNUM || nextType === MIDNUMLET) &&

                nextNextType === NUMERIC) {

            return false;

        }

        // WB4. Ignore format and extend characters.

        if (type === EXTEND || type === FORMAT ||

                prevType === EXTEND || prevType === FORMAT ||

                nextType === EXTEND || nextType === FORMAT) {

            return false;

        }

        // WB3. Don't break inside CRLF.

        if (type === CR && nextType === LF) {

            return false;

        }

        // WB3a. Break before newlines (including CR and LF).

        if (type === NEWLINE || type === CR || type === LF) {

            return true;

        }

        // WB3b. Break after newlines (including CR and LF).

        if (nextType === NEWLINE || nextType === CR || nextType === LF) {

            return true;

        }

        // WB13. Don't break between Katakana characters.

        if (type === KATAKANA && nextType === KATAKANA) {

            return false;

        }

        // WB13a. Don't break from extenders.

        if (nextType === EXTENDNUMLET &&

                (type === ALETTER || type === NUMERIC || type === KATAKANA ||

                type === EXTENDNUMLET)) {

            return false;

        }

        // WB13b. Don't break from extenders.

        if (type === EXTENDNUMLET &&

                (nextType === ALETTER || nextType === NUMERIC ||

                nextType === KATAKANA)) {

            return false;

        }

        // Break after any character not covered by the rules above.

        return true;

    }

};

Text.WordBreak = WordBreak;

}, '3.18.1', {"requires": ["array-extras", "text-data-wordbreak"]});