/*
 * jQuery Field Plug-in
 *
 * Copyright (c) 2007 Dan G. Switzer, II
 *
 * Dual licensed under the MIT and GPL licenses:
 *   http://www.opensource.org/licenses/mit-license.php
 *   http://www.gnu.org/licenses/gpl.html
 *
 * Revision: 15
 * Version: 0.9.3
 *
 * NOTES: The getValue() and setValue() methods are designed to be
 * executed on single field (i.e. any field that would share the same
 * "name" attribute--a single text box, a group of checkboxes or radio
 * elements, etc.)
 *
 * Revision History
 * v0.9.3
 * - Enhanced createCheckboxRange() to trigger change handler for each checkbox
 *   being changed
 * - Enhanced createCheckboxRange() to pass in event object when triggering click
 *   callback
 * 
 * v0.9.2
 * - Fixed code for jQuery v1.3.x support
 * - Fixed bug #6333 - setValue when value is typeof "number" and it is 0 (zero)
 * - Fixed bug in autoAdvance where it wasn't correctly advancing to the next field
 * - Fixed bug in createCheckboxRange where it where the high value wouldn't always
 *   be unchecked/checked
 * 
 * v0.9.1
 * - Optimized the createCheckboxRange to reduced complexity and code size.
 *   Functionality has not changed.
 * 
 * v0.9
 * - Removed createCheckboxRange custom event, this fixes problems with
 *   older jQuery versions that have problems with the trigger
 * - Changed the limitSelection() function to use an options argument, 
 *   instead of all the individual arguments
 * 
 * v0.8.1
 * - createCheckboxRange() no longer breaks the chain
 * - Added callback to createCheckboxRange() (the trigger() method 
 *   does not execute correctly in jQuery v1.1.2, so this functionality 
 *   doesn't work in that version.)
 * - Added configurable setting for the [SHIFT] key bind to the 
 *   createCheckboxRange().
 * - Added the $.Field.setProperty() and getProperty() methods
 * 
 * v0.8
 * - Fixed "bug in checkbox range" (http://plugins.jquery.com/node/1642)
 * - Fixed "Bug when setting value on a select element and the select is empty"
 *   (http://plugins.jquery.com/node/1281)
 *
 * v0.7.1
 * - Changed a comma in code to a semi-colon in a variable definition line
 * - Fixed code to work in min mode
 * - Fixed bug in hashForm() that would not see struct keys with empty values
 *
 * v0.7
 * - Added tabIndex related function (getTabIndex, moveNext, movePrev, moveIndex)
 *
 * v0.6
 * - Fixed bug in the $.formHash() where the arrayed form elements would
 *   not correctly report their values.
 * - Added the $.createCheckboxRange() which allow you to select multiple
 *   checkbox elements by doing a [SHIFT] + click.
 *
 * v0.5
 * - Added $.limitSelection() method for limiting the number of
 *   selection in a select-multiple of checkbox array.
 *
 * v0.4.1
 * - Moved $.type and $.isType into private functions
 * - Rewrote $type() function to use instanceof operator
 *
 * v0.4
 * - Added the formHash() method
 *
 * v0.3
 * - First public release
 *
*/
(function($){

    // set the defaults
    var defaults = {
        // use a comma as the string delimiter
        delimiter: ",",
        // the default key binding to check for when using the createCheckboxRange()
        checkboxRangeKeyBinding: "shiftKey",
        // for methods that could return either a string or array, decide default behavior
        useArray: false
    };

    // set default options
    $.Field = {
		version: "0.9.3",
        setDefaults: function(options){
            $.extend(defaults, options);
        },
        setProperty: function(prop, value){
            defaults[prop] = value;
        },
        getProperty: function(prop){
            return defaults[prop];
        }
    };


    /*
     * jQuery.fn.fieldArray()
     *
     * returns either an array of values or a jQuery object
     *
     * NOTE: This *MAY* break the jQuery chain
     *
     * Examples:
     * $("input[name='name']").fieldArray();
     * > Gets the current value of the name text element
     *
     * $("input[name='name']").fieldArray(["Dan G. Switzer, II"]);
     * > Sets the value of the name text element to "Dan G. Switzer, II"
     *
     * $("select[name='state']").fieldArray();
     * > Gets the current value of the state text element
     *
     * $("select[name='state']").setValue(["OH","NY","CA"]);
     * > Sets the selected value of the "state" select element to OH, NY and CA
     *
     */
    // this will set/get the values for a field based upon and array
    $.fn.fieldArray = function(v){
        var t = $type(v);

        // if no value supplied, return an array of values
        if( t == "undefined" ) return getValue(this);

        // convert the number/string into an array
        if( t == "string" ||  t == "number" ){
            v = v.toString().split(defaults.delimiter);
            t = "array";
        }

        // set the value -- doesn't break the chaing
        if( t == "array" ) return setValue(this, v);

        // if we don't know what do to, don't break the chain
        return this;
    };

    /*
     * jQuery.fn.getValue()
     *
     * returns String - a comma delimited list of values for the field
     *
     * NOTE: Breaks the jQuery chain, since it returns a string.
     *
     * Examples:
     * $("input[name='name']").getValue();
     * > This would return the value of the name text element
     *
     * $("select[name='state']").getValue();
     * > This would return the currently selected value of the "state" select element
     *
     */
    // the getValue() method -- break the chain
    $.fn.getValue = function(){
        // return the values as a comma-delimited string
        return getValue(this).join(defaults.delimiter);
    };

    /*
     * getValue()
     *
     * returns Array - an array of values for the field
     *
     */
    // the getValue() method -- break the chain
    var getValue = function(jq){
        var v = [];

        jq.each(
            function (lc){
                // get the current type
                var t = getType(this);

                switch( t ){
                    case "checkbox": case "radio":
                        // if the checkbox or radio element is checked
                        if( this.checked ) v.push(this.value);
                    break;

                    case "select":
                        if( this.type == "select-one" ){
                            v.push( (this.selectedIndex == -1) ? "" : getOptionVal(this[this.selectedIndex]) );
                        } else {
                            // loop through all element in the array for this field
                            for( var i=0; i < this.length; i++ ){
                                // if the element is selected, get the selected values
                                if( this[i].selected ){
                                    // append the selected value, if the value property doesn't exist, use the text
                                    v.push(getOptionVal(this[i]));
                                }
                            }
                        }
                    break;

                    case "text":
                        v.push(this.value);
                    break;
                }
            }
        );

        // return the values as an array
        return v;
    };

    /*
     * setValue()
     *
     * returns jQuery object
     *
     * NOTE: This does *NOT* break the jQuery chain
     *
     * Examples:
     * $("input[name='name']").setValue("Dan G. Switzer, II");
     * > Sets the value of the name text element to "Dan G. Switzer, II"
     *
     * $("select[name='state']").setValue("OH");
     * > Sets the selected value of the "state" select element to "OH"
     *
     */
    // the setValue() method -- does *not* break the chain
    $.fn.setValue = function(v){
        // f no value, set to empty string
        return setValue(this, ((!v && (v !== 0)) ? [""] : v.toString().split(defaults.delimiter)));
    };

    /*
     * setValue()
     *
     * returns jQuery object
     *
     */
    // the setValue() method -- does *not* break the chain
    var setValue = function(jq, v){
        jq.each(
            function (lc){
                var t = getType(this), x;

                switch( t ){
                    case "checkbox": case "radio":
                        if( valueExists(v, this.value) ) this.checked = true;
                        else this.checked = false;
                    break;

                    case "select":
                        var bSelectOne = (this.type == "select-one");
                        var bKeepLooking = true; // if select-one type, then only select the first value found
                        // loop through all element in the array for this field
                        for( var i=0; i < this.length; i++ ){
                            x = getOptionVal(this[i]);
                            bSelectItem = valueExists(v, x);
                            if( bSelectItem ){
                                this[i].selected = true;
                                // if a select-one element
                                if( bSelectOne ){
                                    // no need to look farther
                                    bKeepLooking = false;
                                    // stop the loop
                                    break;
                                }
                            } else if( !bSelectOne ) this[i].selected = false;
                        }
                        // if a select-one box and nothing selected, then try to select the default value
                        if( bSelectOne && bKeepLooking && !!this[0] ){
                            this[0].selected = true;
                        }
                    break;

                    case "text":
                        this.value = v.join(defaults.delimiter);
                    break;
                }

            }
        );

        return jq;
    };

    /*
     * jQuery.fn.formHash()
     *
     * returns either an hash table of form fields or a jQuery object
     *
     * NOTE: This *MAY* break the jQuery chain
     *
     * Examples:
     * $("#formName").formHash();
     * > Returns a hash map of all the form fields and their values
     *
     * $("#formName").formHash({"name": "Dan G. Switzer, II", "state": "OH"});
     * > Returns the jQuery chain and sets the fields "name" and "state" with
     * > the values "Dan G. Switzer, II" and "OH" respectively.
     *
     */
    // the formHash() method -- break the chain
    $.fn.formHash = function(inHash){
        var bGetHash = (arguments.length == 0);
        // create a hash to return
        var stHash = {};

        // run the code for each form
        this.filter("form").each(
            function (){
                // get all the form elements
                var els = this.elements, el, n, stProcessed = {}, jel;

                // loop through the elements and process
                for( var i=0, elsMax = els.length; i < elsMax; i++ ){
                    el = els[i]; 
                    n = el.name;

                    // if the element doesn't have a name, then skip it
                    if( !n || stProcessed[n] ) continue;

                    // create a jquery object to the current named form elements
                    var jel = $(el.tagName.toLowerCase() + "[name='"+n+"']", this);

                    // if we're getting the values, get them now
                    if( bGetHash ){
                        stHash[n] = jel[defaults.useArray ? "fieldArray" : "getValue"]();
                    // if we're setting values, set them now
                    } else if( typeof inHash[n] != "undefined" ){
                        jel[defaults.useArray ? "fieldArray" : "setValue"](inHash[n]);
                    }

                    stProcessed[n] = true;
                }
            }
        );

        // if getting a hash map return it, otherwise return the jQuery object
        return (bGetHash) ? stHash : this;
    };

    /*
     * jQuery.fn.autoAdvance()
     *
     * Finds all text-based input fields and makes them autoadvance to the next
     * fields when they've met their maxlength property.
     *
     *
     * Examples:
     * $("#form").autoAdvance();
     * > When a field reaches it's maxlength attribute value, it'll advance to the
     * > next field in the form's tabindex.
     *
     * $("#form").autoAdvance(callback);
     * > Automatic advances to next field and triggers the callback function on the
     * > field the user left.
     *
     */
    // the autoAdvance() method
    $.fn.autoAdvance = function(callback){
        return this.find(":text,:password,textarea").bind(
            "keyup.autoAdvance",
            function (e){
                var
                    // get the field
                    $field = $(this),
                    // get the maxlength for the field
                    iMaxLength = parseInt($field.attr("maxlength"), 10);

                // if the user tabs to the field, exit event handler
                // this will prevent movement if the field is already
                // field in with the max number of characters
                if( isNaN(iMaxLength) || ("|9|16|37|38|39|40|".indexOf("|" + e.keyCode + "|") > -1) ) return true;

                // if the value of the field is greater than maxlength attribute,
                // then move the focus to the next field
                if( $field.getValue().length >= $field.attr("maxlength") ){
                    // move to the next field and select the existing value
                    var $next = $field.moveNext().select();
                    if( $.isFunction(callback) ) callback.apply($field, [$next]);
                }
            }
        );
    };

    /*
     * jQuery.fn.moveNext()
     *
     * places the focus in the next form field. if the field element is
     * the last in the form array, it'll return to the top.
     *
     * returns a jQuery object pointing to the next field element
     *
     * NOTE: if the selector returns multiple items, the first item is used.
     *
     *
     * Examples:
     * $("#firstName").moveNext();
     * > Moves the focus to the next form field found after firstName
     *
     */
    // the moveNext() method
    $.fn.moveNext = function(){
        return this.moveIndex("next");
    };

    /*
     * jQuery.fn.movePrev()
     *
     * places the focus in the previous form field. if the field element is
     * the first in the form array, it'll return to the last element.
     *
     * returns a jQuery object pointing to the previos field element
     *
     * NOTE: if the selector returns multiple items, the first item is used
     *
     * Examples:
     * $("#firstName").movePrev();
     * > Moves the focus to the next form field found after firstName
     *
     */
    // the movePrev() method
    $.fn.movePrev = function(){
        return this.moveIndex("prev");
    };

    /*
     * jQuery.fn.moveIndex()
     *
     * Places the tab index into the specified index position
     *
     * returns a jQuery object pointing to the previos field element
     *
     * NOTE: if the selector returns multiple items, the first item is used
     *
     * Examples:
     * $("#firstName").movePrev();
     * > Moves the focus to the next form field found after firstName
     *
     */
    // the moveIndex() method
    $.fn.moveIndex = function(i){
        // get the current position and elements
        var aPos = getFieldPosition(this);

        // if a string option has been specified, calculate the position
        if( i == "next" ) i = aPos[0] + 1; // get the next item
        else if( i == "prev" ) i = aPos[0] - 1; // get the previous item

        // make sure the index position is within the bounds of the elements array
        if( i < 0 ) i = aPos[1].length - 1;
        else if( i >= aPos[1].length ) i = 0;

        return $(aPos[1][i]).trigger("focus");
    };

    /*
     * jQuery.fn.getTabIndex()
     *
     * gets the current tab index of the first element found in the selector
     *
     * NOTE: if the selector returns multiple items, the first item is used
     *
     * Examples:
     * $("#firstName").getTabIndex();
     * > Gets the tabIndex for the firstName field
     *
     */
    // the getTabIndex() method
    $.fn.getTabIndex = function(){
        // return the position of the form field
        return getFieldPosition(this)[0];
    };

    var getFieldPosition = function (jq){
        var
            // get the first matching field
            $field = jq.filter("input, select, textarea").get(0),
            // store items with a tabindex
            aTabIndex = [],
            // store items with no tabindex
            aPosIndex = [];

        // if there is no match, return 0
        if( !$field ) return [-1, []];

        // make a single pass thru all form elements
        $.each(
            $field.form.elements,
            function (i, o){
                if( o.tagName != "FIELDSET" && !o.disabled ){
                    if( o.tabIndex > 0 ){
                        aTabIndex.push(o);
                    } else {
                        aPosIndex.push(o);
                    }
                }
            }
        );

        // sort the fields that had tab indexes
        aTabIndex.sort(
            function (a, b){
                return a.tabIndex - b.tabIndex;
            }
        );

        // merge the elements to create the correct tab position
        aTabIndex = $.merge(aTabIndex, aPosIndex);

        for( var i=0; i < aTabIndex.length; i++ ){
            if( aTabIndex[i] == $field ) return [i, aTabIndex];
        }

        return [-1, aTabIndex];
    };

    /*
     * jQuery.fn.limitSelection()
     *
     * limits the number of items that can be selected
     *
     * Examples:
     * $("input:checkbox").limitSelection(3);
     * > No more than 3 items can be selected
     *
     * $("input:checkbox").limitSelection(2, {onsuccess: function (), onfailure: function ()});
     * > Limits the selection to 2 items and runs the callback function when
     * > more than 2 items have been selected.
     *
     * NOTE: Current when a "select-multiple" option undoes the selection,
     * it selects the first 3 options in the array--which isn't necessarily
     * the first 3 options the user selected. This is not the most desired
     * behavior.
     *
     */
    $.fn.limitSelection = function(limit, options){
        // get the options to use
        var opt = jQuery.extend(
            (limit && limit.constructor == Object ? limit : {
                    limit: limit
                , onsuccess: function (limit){ return true; }
                , onfailure: function (limit){ alert("You can only select a maximum a of " + limit + " items."); return false; }
            })
            , options);
        
        var self = this;

        var getCount = function (el){
            if( el.type == "select-multiple" ) return $("option:selected", self).length;
            else if( el.type == "checkbox" ) return self.filter(":checked").length;
            return 0;
        };

        var undoSelect = function (){
            // reduce selection to n items
            setValue(self, getValue(self).slice(0, opt.limit));
            // do callback
            return opt.onfailure.apply(self, [opt.limit]);
        };

        return this.bind(
            (!!self[0] && self[0].type == "select-multiple") ? "change.limitSelection" : "click.limitSelection",
            function (){
                if( getCount(this) > opt.limit ){
                    // run callback, it must return false to prevent action
                    return (this.type == "select-multiple") ? undoSelect() : opt.onfailure.apply(self, [opt.limit]);
                }
                opt.onsuccess.apply(self, [opt.limit]);
                return true;
            }
        );
    };

    /*
     * jQuery.fn.createCheckboxRange()
     *
     * limits the number of items that can be selected
     *
     * Examples:
     * $("input:checkbox").createCheckboxRange();
     * > Allows a [SHIFT] + mouseclick to select all the items from the last
     * > checked checkmark to the current checkbox.
     *
     * $("input:checkbox").createCheckboxRange(callback);
     * > Runs the callback method for each item who's checked status changes.
     * > This allows you to build hooks to highlight rows.
     *
     */
    $.fn.createCheckboxRange = function(callback){
        // get the options to use
        var opt = jQuery.extend(
            (callback && callback.constructor == Object ? callback : {
                    bind: defaults.checkboxRangeKeyBinding
				, click: callback
            })
            , callback);

		var iLastSelection = 0, self = this, bCallback = $.isFunction(opt.click);

        // if there's a call back, bind it now and run it
        if( bCallback ) 
			this.each(function (){opt.click.apply(this, [$.event.fix({type: null}), $(this).is(":checked")])});
        
        // loop through each checkbox and return the jQuery object
        return this.each(
            function (){
                // only perform this action on checkboxes
                if( this.type != "checkbox" ) return false;
                var el = this;

                var updateLastCheckbox = function (e){
                    iLastSelection = self.index(e.target);
                };

                var checkboxClicked = function (e){
                    var bSetChecked = this.checked, current = self.index(e.target), low = Math.min(iLastSelection, current), high = Math.max(iLastSelection+1, current);
                    // run the callback for the clicked item
					if( bCallback ) $(this).each(function (){opt.click.apply(this, [e, bSetChecked])});
                    // if we don't detect the keypress, exit function
                    if( !e[opt.bind] ) return;
                    
                    // loop through the items in the selected range
                    for( var i=low; i < high; i++ ){
						// make sure to correctly set the checked status and run the change handler
						var item = self.eq(i).attr("checked", bSetChecked ? "checked" : "").trigger("change");
                        // run the callback
						if( bCallback ) opt.click.apply(item[0], [e, bSetChecked]);
                    }
                    
                    return true;
                };
                
                $(this)
                    // unbind the events so we can re-run the createCheckboxRange() plug-in for dynamically created elements
                    .unbind("click.createCheckboxRange")

                    // bind the functions, we bind on blur for keyboard selected items
                    .bind("click.createCheckboxRange", checkboxClicked)
                    .bind("click.createCheckboxRange", updateLastCheckbox)
                    ;

                return true;
            }
        );
    };

    // determines how to process a field
    var getType = function (el){
        var t = el.type;

        switch( t ){
            case "select": case "select-one": case "select-multiple":
                t = "select";
                break;
            case "text": case "hidden": case "textarea": case "password": case "button": case "submit": case "submit":
                t = "text";
                break;
            case "checkbox": case "radio":
                t = t;
                break;
        }
        return t;
    };

    // gets the value of a select element
    var getOptionVal = function (el){
         return jQuery.browser.msie && !(el.attributes['value'].specified) ? el.text : el.value;
    };

    // checks to see if a value exists in an array
    var valueExists = function (a, v){
        return ($.inArray(v, a) > -1);
    };

    // correctly gets the type of an object (including array/dates)
    var $type = function (o){
        var t = (typeof o).toLowerCase();

        if( t == "object" ){
            if( o instanceof Array ) t = "array";
            else if( o instanceof Date ) t = "date";
        }
        return t;
    };

    // checks to see if an object is the specified type
    var $isType = function (o, v){
        return ($type(o) == String(v).toLowerCase());
    };

})(jQuery);