/*
* @name columnFilters
* @type jQuery
* @param Object settings;
*			wildCard	:	A character to be used as a match all wildcard when searching, Leave empty for no wildcards.
*			notCharacter	:	The character to use at the start of any search text to specify that the results should NOT contain the following text.
*			caseSensitive	:	True if the filter search's are to be case sensitive.
*			minSearchCharacters	:	The minimum amount of characters that each search string must contain before the search is applied.
*			excludeColumns	:	A zero indexed array of column numbers to not allow filtering on.
*			alternateRowClassNames	:	An array of alternating class names for each row returned after filtering in order to keep odd and even row styling on tables. Maximum of two items.
*			underline	:	Set to true if the script is to underline the search text whilst filtering is in progress... good for tables with lots of rows where the filter may take a second. (not in Opera)

*/

(function($) {

    $.fn.columnFilters = function(settings) {
        var defaults = {
            wildCard: "*",
            notCharacter: "!",
            caseSensitive: false,
            minSearchCharacters: 1,
            excludeColumns: [],
            alternateRowClassNames: [],
            underline: false
        };
        settings = $.extend(defaults, settings);

        return this.each(function() {

            function regexEscape(txt, omit) {
                var specials = ['/', '.', '*', '+', '?', '|',
								'(', ')', '[', ']', '{', '}', '\\'];

                if (omit) {
                    for (var i = 0; i < specials.length; i++) {
                        if (specials[i] === omit) { specials.splice(i, 1); }
                    }
                }

                var escapePatt = new RegExp('(\\' + specials.join('|\\') + ')', 'g');
                return txt.replace(escapePatt, '\\$1');
            }

            var obj = $(this),
				filterRow = document.createElement('tr'),
				wildCardPatt = new RegExp(regexEscape(settings.wildCard || ''), 'g'),
				filter;

            function addClassToColumn(iColNum, sClassName) {
                $('tbody:first tr', obj).each(
					function() {
					    $('td', this).each(
							function(iCellCount) {
							    if (iCellCount === iColNum) {
							        $(this).addClass(sClassName);
							    }
							});
					}
				);
            }

            function runFilters(event) {
                $('input._filterText', obj).each(
					function(iColCount) {
					    var sFilterTxt = (!settings.wildCard) ? regexEscape(this.value) : regexEscape(this.value, settings.wildCard).replace(wildCardPatt, '.*'),
							bMatch = true,
							sFirst = settings.alternateRowClassNames[0] || '',
							sSecound = settings.alternateRowClassNames[1] || '',
							bOddRow = true;

					    if (settings.notCharacter && sFilterTxt.indexOf(settings.notCharacter) === 0) {
					        sFilterTxt = sFilterTxt.substr(settings.notCharacter.length, sFilterTxt.length);
					        if (sFilterTxt.length > 0) { bMatch = false; }
					    }
					    if (sFilterTxt.length < settings.minSearchCharacters) {
					        sFilterTxt = '';
					    }
					    sFilterTxt = sFilterTxt || '.*';
					    sFilterTxt = settings.wildCard ? '^' + sFilterTxt : sFilterTxt;
					    var filterPatt = settings.caseSensitive ? new RegExp(sFilterTxt) : new RegExp(sFilterTxt, "i");

					    $('tbody:first tr', obj).each(
							function() {
							    $('td', this).each(
									function(iCellCount) {
									    if (iCellCount === iColCount) {
									        var sVal = $(this).text().replace(/(\n)|(\r)/ig, '').replace(/\s\s/ig, ' ').replace(/^\s/ig, '');
									        $(this).removeClass('_match');
									        if (filterPatt.test(sVal) === bMatch) {
									            $(this).addClass('_match');
									        }
									    }
									}
								);

							    if ($('td', this).length !== $('td._match', this).length) {
							        $(this).css('display', 'none');
							    }
							    else {
							        $(this).css('display', '');
							        if (settings.alternateRowClassNames && settings.alternateRowClassNames.length) {
							            $(this).removeClass(sFirst).removeClass(sSecound).addClass((bOddRow) ? sFirst : sSecound);
							            bOddRow = !bOddRow;
							        }
							    }
							}
						);

					    if (settings.underline) {
					        $(this).css('text-decoration', '');
					    }
					}
				);
            }

            function genAlternateClassNames() {
                if (settings.alternateRowClassNames && settings.alternateRowClassNames.length) {
                    var sFirst = settings.alternateRowClassNames[0] || '',
						sSecound = settings.alternateRowClassNames[1] || '',
						bOddRow = true;

                    $('tbody:first tr', obj).each(
						function() {
						    if ($(this).css('display') !== 'none') {
						        $(this).removeClass(sFirst).removeClass(sSecound);
						        $(this).addClass((bOddRow) ? sFirst : sSecound);
						        bOddRow = !bOddRow;
						    }
						}
					);
                }
            }

            $('tbody:first tr:first td', obj).each(
				function(iColCount) {
				    var filterColumn = document.createElement('td'),
						filterBox = document.createElement('input');

				    $(filterBox).attr('type', 'text').attr('id', '_filterText' + iColCount).addClass('_filterText');
				    $(filterBox).keyup(
						function() {
						    clearTimeout(filter);
						    filter = setTimeout(runFilters, $('tbody:first tr', obj).length * 2);
						    if (settings.underline) {
						        $(filterBox).css('text-decoration', 'underline');
						    }
						}
					);
				    $(filterColumn).append(filterBox);
				    $(filterRow).append(filterColumn);

				    if (settings.excludeColumns && settings.excludeColumns.length) {
				        for (var i = 0; i < settings.excludeColumns.length; i++) {
				            if (settings.excludeColumns[i] === iColCount) {
				                $(filterBox).css('display', 'none');
				            }
				        }
				    }

				    addClassToColumn(iColCount, '_filterCol' + iColCount);
				}
			);

            $(filterRow).addClass('filterColumns');
            $('thead:first', obj).append(filterRow);
            genAlternateClassNames();
            settings.notCharacter = regexEscape(settings.notCharacter || '');
        });
    };

})(jQuery);