sebastian-software/core

/*
==================================================================================================
    Core - JavaScript Foundation
    Copyright 2010-2012 Zynga Inc.
    Copyright 2012-2014 Sebastian Werner
==================================================================================================
*/

"use strict";

/**
 * Collection of serialization methods for form items
 */
core.Module("core.bom.FormItem",
{
    /**
     * {Boolean} Returns whether the form @item {Element} is successful (should be submitted to the server)
     */
    isSuccessful: function(item)
    {
        if (jasy.Env.isSet("debug"))
        {
            core.Assert.isEqual(arguments.length, 1);
            core.dom.Node.assertIsNode(item);
        }

        if (!item.name || item.disabled) {
            return false;
        }

        switch (item.type)
        {
            case "button":
            case "reset":
                return false;

            case "radio":
            case "checkbox":
                return item.checked;

            case "image":
            case "submit":
                return item == (item.ownerDocument || item.document).activeElement;
        }

        return true;
    },


    /**
     * {String} Finds a label for the given form @item {Element} in the
     * given @root {Element?document} to be shown in e.g. error messages.
     */
    getLabel : function(item, root)
    {
        if (!root) {
            root = document.body;
        }

        // Find matching label
        if (item.id)
        {
            var label = root.querySelector("label[for=" + item.id + "]");
            if (label)
            {
                label = label.innerText;

                if (label)
                {
                    // Strip marker for required field
                    if (core.String.endsWith(label, "*")) {
                        label = label.slice(0, label.length-1);
                    }

                    return label;
                }
            }
        }

        var label = item.getAttribute("data-label");
        return label || item.placeholder || item.name || null;
    },


    /**
     * {String} Returns the value of the given form @item {Element}.
     */
    getValue : function(item)
    {
        if (jasy.Env.isSet("debug"))
        {
            core.Assert.isEqual(arguments.length, 1);
            core.dom.Node.assertIsNode(item);
        }

        if (item.tagName == "SELECT")
        {
            // Inspired by jQuery
            var index = item.selectedIndex;
            var options = item.options;
            var one = item.type === "select-one" || index < 0;
            var max = one ? index + 1 : options.length;
            var values = one ? null : [];
            var i = index < 0 ? max : one ? index : 0;

            for (; i<max; i++)
            {
                var option = options[i];

                // Ignore disabled options
                if (option.disabled) {
                    continue;
                }

                // Ignore options which are in disabled optgroups
                var parent = option.parentNode;
                if (parent.disabled && parent.tagName == "OPTGROUP") {
                    continue;
                }

                var value = option.value;

                if (one) {
                    return value;
                } else {
                    values.push(value);
                }
            }

            return values;
        }
        else
        {
            return core.String.interpret(item.value || item.text);
        }
    },


    /**
     * {Boolean} Return whether from @item {Element} there is only exactly one value storable.
     */
    isExplicitSingle : function(item)
    {
        // Currently only true for radio fields where native behavior actually prevents
        // selecting two radio buttons with the same name. Other fields like text fields
        // and even select fields are all serialized and added the result.
        return item.type == "radio";
    },


    /**
     * {String} Returns the serialized representation of the given form @item {Element}.
     */
    serialize: function(item)
    {
        if (jasy.Env.isSet("debug"))
        {
            core.Assert.isEqual(arguments.length, 1);
            core.dom.Node.assertIsNode(item);
            core.Assert.isType(item.name, "String");
        }

        var name = encodeURIComponent(item.name);
        var value = this.getValue(item);

        // Support for select boxes with multiple values
        if (value instanceof Array)
        {
            var result = [];
            for (var i=0, l=value.length; i<l; i++) {
                result.push(name + "=" + encodeURIComponent(value[i]));
            }

            return result.join("&");
        }

        // Or everything else
        else
        {
            return name + "=" + encodeURIComponent(value);
        }
    }
});