class.forms.php

<?php
/*********************************************************************
    class.forms.php

    osTicket forms framework

    Jared Hancock <jared@osticket.com>
    Copyright (c)  2006-2013 osTicket
    http://www.osticket.com

    Released under the GNU General Public License WITHOUT ANY WARRANTY.
    See LICENSE.TXT for details.

    vim: expandtab sw=4 ts=4 sts=4:
**********************************************************************/

/**
 * Form template, used for designing the custom form and for entering custom
 * data for a ticket
 */
class Form {
    var $fields = array();
    var $title = '';
    var $instructions = '';

    var $_errors = null;
    var $_source = false;

    function __construct($fields=array(), $source=null, $options=array()) {
        $this->fields = $fields;
        foreach ($fields as $k=>$f) {
            $f->setForm($this);
            if (!$f->get('name') && $k)
                $f->set('name', $k);
        }
        if (isset($options['title']))
            $this->title = $options['title'];
        if (isset($options['instructions']))
            $this->instructions = $options['instructions'];
        // Use POST data if source was not specified
        $this->_source = ($source) ? $source : $_POST;
    }
    function data($source) {
        foreach ($this->fields as $name=>$f)
            if (isset($source[$name]))
                $f->value = $source[$name];
    }

    function getFields() {
        return $this->fields;
    }

    function getField($name) {
        $fields = $this->getFields();
        foreach($fields as $f)
            if(!strcasecmp($f->get('name'), $name))
                return $f;
        if (isset($fields[$name]))
            return $fields[$name];
    }

    function getTitle() { return $this->title; }
    function getInstructions() { return $this->instructions; }
    function getSource() { return $this->_source; }
    function setSource($source) { $this->_source = $source; }

    /**
     * Validate the form and indicate if there no errors.
     *
     * Parameters:
     * $filter - (callback) function to receive each field and return
     *      boolean true if the field's errors are significant
     */
    function isValid($include=false) {
        if (!isset($this->_errors)) {
            $this->_errors = array();
            $this->getClean();
            foreach ($this->getFields() as $field)
                if ($field->errors() && (!$include || $include($field)))
                    $this->_errors[$field->get('id')] = $field->errors();
        }
        return !$this->_errors;
    }

    function getClean() {
        if (!$this->_clean) {
            $this->_clean = array();
            foreach ($this->getFields() as $key=>$field) {
                if (!$field->hasData())
                    continue;
                $this->_clean[$key] = $this->_clean[$field->get('name')]
                    = $field->getClean();
            }
            unset($this->_clean[""]);
        }
        return $this->_clean;
    }

    function errors() {
        return $this->_errors;
    }

    function render($staff=true, $title=false, $options=array()) {
        if ($title)
            $this->title = $title;
        if (isset($options['instructions']))
            $this->instructions = $options['instructions'];
        $form = $this;
        if ($staff)
            include(STAFFINC_DIR . 'templates/dynamic-form.tmpl.php');
        else
            include(CLIENTINC_DIR . 'templates/dynamic-form.tmpl.php');
    }

    function getMedia() {
        static $dedup = array();

        foreach ($this->getFields() as $f) {
            if (($M = $f->getMedia()) && is_array($M)) {
                foreach ($M as $type=>$files) {
                    foreach ($files as $url) {
                        $key = strtolower($type.$url);
                        if (isset($dedup[$key]))
                            continue;

                        self::emitMedia($url, $type);

                        $dedup[$key] = true;
                    }
                }
            }
        }
    }

    static function emitMedia($url, $type) {
        if ($url[0] == '/')
            $url = ROOT_PATH . substr($url, 1);

        switch (strtolower($type)) {
        case 'css': ?>
        <link rel="stylesheet" type="text/css" href="<?php echo $url; ?>"/><?php
            break;
        case 'js': ?>
        <script type="text/javascript" src="<?php echo $url; ?>"></script><?php
            break;
        }
    }
}

require_once(INCLUDE_DIR . "class.json.php");

class FormField {
    static $widget = false;

    var $ht = array(
        'label' => 'Unlabeled',
        'required' => false,
        'default' => false,
        'configuration' => array(),
    );

    var $_form;
    var $_cform;
    var $_clean;
    var $_errors = array();
    var $_widget;
    var $answer;
    var $parent;
    var $presentation_only = false;

    static $types = array(
        /* @trans */ 'Basic Fields' => array(
            'text'  => array(   /* @trans */ 'Short Answer', 'TextboxField'),
            'memo' => array(    /* @trans */ 'Long Answer', 'TextareaField'),
            'thread' => array(  /* @trans */ 'Thread Entry', 'ThreadEntryField', false),
            'datetime' => array(/* @trans */ 'Date and Time', 'DatetimeField'),
            'phone' => array(   /* @trans */ 'Phone Number', 'PhoneField'),
            'bool' => array(    /* @trans */ 'Checkbox', 'BooleanField'),
            'choices' => array( /* @trans */ 'Choices', 'ChoiceField'),
            'files' => array(   /* @trans */ 'File Upload', 'FileUploadField'),
            'break' => array(   /* @trans */ 'Section Break', 'SectionBreakField'),
        ),
    );
    static $more_types = array();
    static $uid = 100;

    function __construct($options=array()) {
        $this->ht = array_merge($this->ht, $options);
        if (!isset($this->ht['id']))
            $this->ht['id'] = self::$uid++;
    }

    function __clone() {
        $this->_widget = null;
        $this->ht['id'] = self::$uid++;
    }

    static function addFieldTypes($group, $callable) {
        static::$more_types[$group][] = $callable;
    }

    static function allTypes() {
        if (static::$more_types) {
            foreach (static::$more_types as $group => $entries)
                foreach ($entries as $c)
                    static::$types[$group] = array_merge(
                            static::$types[$group] ?: array(), call_user_func($c));

            static::$more_types = array();
        }
        return static::$types;
    }

    static function getFieldType($type) {
        foreach (static::allTypes() as $group=>$types)
            if (isset($types[$type]))
                return $types[$type];
    }

    function get($what) {
        return $this->ht[$what];
    }
    function set($field, $value) {
        $this->ht[$field] = $value;
    }

    /**
     * getClean
     *
     * Validates and cleans inputs from POST request. This is performed on a
     * field instance, after a DynamicFormSet / DynamicFormSection is
     * submitted via POST, in order to kick off parsing and validation of
     * user-entered data.
     */
    function getClean() {
        if (!isset($this->_clean)) {
            $this->_clean = (isset($this->value))
                ? $this->value : $this->parse($this->getWidget()->value);

            if ($vs = $this->get('cleaners')) {
                if (is_array($vs)) {
                    foreach ($vs as $cleaner)
                        if (is_callable($clenaer))
                            $this->_clean = $cleaner($this, $this->_clean);
                }
                elseif (is_callable($vs))
                    $this->_clean = $vs($this, $this->_clean);
            }

            if ($this->isVisible())
                $this->validateEntry($this->_clean);
        }
        return $this->_clean;
    }
    function reset() {
        $this->_clean = $this->_widget = null;
    }

    function errors() {
        return $this->_errors;
    }
    function addError($message, $field=false) {
        if ($field)
            $this->_errors[$field] = $message;
        else
            $this->_errors[] = $message;
    }

    function isValidEntry() {
        $this->validateEntry();
        return count($this->_errors) == 0;
    }

    /**
     * validateEntry
     *
     * Validates user entry on an instance of the field on a dynamic form.
     * This is called when an instance of this field (like a TextboxField)
     * receives data from the user and that value should be validated.
     *
     * Parameters:
     * $value - (string) input from the user
     */
    function validateEntry($value) {
        if (!$value && count($this->_errors))
            return;

        # Validates a user-input into an instance of this field on a dynamic
        # form
        if ($this->get('required') && !$value && $this->hasData())
            $this->_errors[] = sprintf(__('%s is a required field'),
                $this->getLabel());

        # Perform declared validators for the field
        if ($vs = $this->get('validators')) {
            if (is_array($vs)) {
                foreach ($vs as $validator)
                    if (is_callable($validator))
                        $validator($this, $value);
            }
            elseif (is_callable($vs))
                $vs($this, $value);
        }
    }

    /**
     * isVisible
     *
     * If this field has visibility configuration, then it will parse the
     * constraints with the visibility configuration to determine if the
     * field is visible and should be considered for validation
     */
    function isVisible() {
        $config = $this->getConfiguration();
        if ($this->get('visibility') instanceof VisibilityConstraint) {
            return $this->get('visibility')->isVisible($this);
        }
        return true;
    }

    /**
     * parse
     *
     * Used to transform user-submitted data to a PHP value. This value is
     * not yet considered valid. The ::validateEntry() method will be called
     * on the value to determine if the entry is valid. Therefore, if the
     * data is clearly invalid, return something like NULL that can easily
     * be deemed invalid in ::validateEntry(), however, can still produce a
     * useful error message indicating what is wrong with the input.
     */
    function parse($value) {
        return is_string($value) ? trim($value) : $value;
    }

    /**
     * to_php
     *
     * Transforms the data from the value stored in the database to a PHP
     * value. The ::to_database() method is used to produce the database
     * valse, so this method is the compliment to ::to_database().
     *
     * Parameters:
     * $value - (string or null) database representation of the field's
     *      content
     */
    function to_php($value) {
        return $value;
    }

    /**
     * to_database
     *
     * Determines the value to be stored in the database. The database
     * backend for all fields is a text field, so this method should return
     * a text value or NULL to represent the value of the field. The
     * ::to_php() method will convert this value back to PHP.
     *
     * Paremeters:
     * $value - PHP value of the field's content
     */
    function to_database($value) {
        return $value;
    }

    /**
     * toString
     *
     * Converts the PHP value created in ::parse() or ::to_php() to a
     * pretty-printed value to show to the user. This is especially useful
     * for something like dates which are stored considerably different in
     * the database from their respective human-friendly versions.
     * Furthermore, this method allows for internationalization and
     * localization.
     *
     * Parametes:
     * $value - PHP value of the field's content
     */
    function toString($value) {
        return (string) $value;
    }

    function __toString() {
        return $this->toString($this->value);
    }

    /**
     * Returns an HTML friendly value for the data in the field.
     */
    function display($value) {
        return Format::htmlchars($this->toString($value));
    }

    /**
     * Returns a value suitable for exporting to a foreign system. Mostly
     * useful for things like dates and phone numbers which should be
     * formatted using a standard when exported
     */
    function export($value) {
        return $this->toString($value);
    }

    /**
     * Convert the field data to something matchable by filtering. The
     * primary use of this is for ticket filtering.
     */
    function getFilterData() {
        return $this->toString($this->getClean());
    }

    function searchable($value) {
        return Format::searchable($this->toString($value));
    }

    function getLabel() { return $this->get('label'); }

    /**
     * getImpl
     *
     * Magic method that will return an implementation instance of this
     * field based on the simple text value of the 'type' value of this
     * field instance. The list of registered fields is determined by the
     * global get_dynamic_field_types() function. The data from this model
     * will be used to initialize the returned instance.
     *
     * For instance, if the value of this field is 'text', a TextField
     * instance will be returned.
     */
    function getImpl($parent=null) {
        // Allow registration with ::addFieldTypes and delayed calling
        $type = static::getFieldType($this->get('type'));
        $clazz = $type[1];
        $inst = new $clazz($this->ht);
        $inst->parent = $parent;
        $inst->setForm($this->_form);
        return $inst;
    }

    function __call($what, $args) {
        // XXX: Throw exception if $this->parent is not set
        if (!$this->parent)
            throw new Exception(sprintf(__('%s: Call to undefined function'),
                $what));
        // BEWARE: DynamicFormField has a __call() which will create a new
        //      FormField instance and invoke __call() on it or bounce
        //      immediately back
        return call_user_func_array(
            array($this->parent, $what), $args);
    }

    function getAnswer() { return $this->answer; }
    function setAnswer($ans) { $this->answer = $ans; }

    function getFormName() {
        if (is_numeric($this->get('id')))
            return substr(md5(
                session_id() . '-field-id-'.$this->get('id')), -16);
        else
            return $this->get('name') ?: $this->get('id');
    }

    function setForm($form) {
        $this->_form = $form;
    }
    function getForm() {
        return $this->_form;
    }
    /**
     * Returns the data source for this field. If created from a form, the
     * data source from the form is returned. Otherwise, if the request is a
     * POST, then _POST is returned.
     */
    function getSource() {
        if ($this->_form)
            return $this->_form->getSource();
        elseif ($_SERVER['REQUEST_METHOD'] == 'POST')
            return $_POST;
        else
            return array();
    }

    function render($mode=null) {
        $rv = $this->getWidget()->render($mode);
        if ($v = $this->get('visibility')) {
            $v->emitJavascript($this);
        }
        return $rv;
    }

    function renderExtras($mode=null) {
        return;
    }

    function getMedia() {
        $widget = $this->getWidget();
        return $widget::$media;
    }

    function getConfigurationOptions() {
        return array();
    }

    /**
     * getConfiguration
     *
     * Loads configuration information from database into hashtable format.
     * Also, the defaults from ::getConfigurationOptions() are integrated
     * into the database-backed options, so that if options have not yet
     * been set or a new option has been added and not saved for this field,
     * the default value will be reflected in the returned configuration.
     */
    function getConfiguration() {
        if (!$this->_config) {
            $this->_config = $this->get('configuration');
            if (is_string($this->_config))
                $this->_config = JsonDataParser::parse($this->_config);
            elseif (!$this->_config)
                $this->_config = array();
            foreach ($this->getConfigurationOptions() as $name=>$field)
                if (!isset($this->_config[$name]))
                    $this->_config[$name] = $field->get('default');
        }
        return $this->_config;
    }

    /**
     * If the [Config] button should be shown to allow for the configuration
     * of this field
     */
    function isConfigurable() {
        return true;
    }

    /**
     * Field type is changeable in the admin interface
     */
    function isChangeable() {
        return true;
    }

    /**
     * Field does not contain data that should be saved to the database. Ie.
     * non data fields like section headers
     */
    function hasData() {
        return true;
    }

    /**
     * Returns true if the field/widget should be rendered as an entire
     * block in the target form.
     */
    function isBlockLevel() {
        return false;
    }

    /**
     * Fields should not be saved with the dynamic data. It is assumed that
     * some static processing will store the data elsewhere.
     */
    function isPresentationOnly() {
        return $this->presentation_only;
    }

    /**
     * Indicates if the field places data in the `value_id` column. This
     * is currently used by the materialized view system
     */
    function hasIdValue() {
        return false;
    }

    /**
     * Indicates if the field has subfields accessible via getSubFields()
     * method. Useful for filter integration. Should connect with
     * getFilterData()
     */
    function hasSubFields() {
        return false;
    }
    function getSubFields() {
        return null;
    }

    /**
     * Indicates if the field provides for searching for something other
     * than keywords. For instance, textbox fields can have hits by keyword
     * searches alone, but selection fields should provide the option to
     * match a specific value or set of values and therefore need to
     * participate on any search builder.
     */
    function hasSpecialSearch() {
        return true;
    }

    function getConfigurationForm($source=null) {
        if (!$this->_cform) {
            $type = static::getFieldType($this->get('type'));
            $clazz = $type[1];
            $T = new $clazz();
            $config = $this->getConfiguration();
            $this->_cform = new Form($T->getConfigurationOptions(), $source);
            if (!$source && $config) {
                foreach ($this->_cform->getFields() as $name=>$f) {
                    if (isset($config[$name]))
                        $f->value = $config[$name];
                    elseif ($f->get('default'))
                        $f->value = $f->get('default');
                }
            }
        }
        return $this->_cform;
    }

    function configure($prop, $value) {
        $this->getConfiguration();
        $this->_config[$prop] = $value;
    }

    function getWidget($widgetClass=false) {
        if (!static::$widget)
            throw new Exception(__('Widget not defined for this field'));
        if (!isset($this->_widget)) {
            $wc = $widgetClass ?: $this->get('widget') ?: static::$widget;
            $this->_widget = new $wc($this);
            $this->_widget->parseValue();
        }
        return $this->_widget;
    }

    function getSelectName() {
        $name = $this->get('name') ?: 'field_'.$this->get('id');
        if ($this->hasIdValue())
            $name .= '_id';

        return $name;
    }
}

class TextboxField extends FormField {
    static $widget = 'TextboxWidget';

    function getConfigurationOptions() {
        return array(
            'size'  =>  new TextboxField(array(
                'id'=>1, 'label'=>__('Size'), 'required'=>false, 'default'=>16,
                    'validator' => 'number')),
            'length' => new TextboxField(array(
                'id'=>2, 'label'=>__('Max Length'), 'required'=>false, 'default'=>30,
                    'validator' => 'number')),
            'validator' => new ChoiceField(array(
                'id'=>3, 'label'=>__('Validator'), 'required'=>false, 'default'=>'',
                'choices' => array('phone'=>__('Phone Number'),'email'=>__('Email Address'),
                    'ip'=>__('IP Address'), 'number'=>__('Number'),
                    'regex'=>__('Custom (Regular Expression)'), ''=>__('None')))),
            'regex' => new TextboxField(array(
                'id'=>6, 'label'=>__('Regular Expression'), 'required'=>true,
                'configuration'=>array('size'=>40, 'length'=>100),
                'visibility' => new VisibilityConstraint(
                    new Q(array('validator__eq'=>'regex')),
                    VisibilityConstraint::HIDDEN
                ),
                'cleaners' => function ($self, $value) {
                    $wrapped = "/".$value."/iu";
                    if (false === @preg_match($value, ' ')
                            && false !== @preg_match($wrapped, ' ')) {
                        return $wrapped;
                    }
                    return $value;
                },
                'validators' => function($self, $v) {
                    if (false === @preg_match($v, ' '))
                        $self->addError(__('Cannot compile this regular expression'));
                })),
            'validator-error' => new TextboxField(array(
                'id'=>4, 'label'=>__('Validation Error'), 'default'=>'',
                'configuration'=>array('size'=>40, 'length'=>60),
                'hint'=>__('Message shown to user if the input does not match the validator'))),
            'placeholder' => new TextboxField(array(
                'id'=>5, 'label'=>__('Placeholder'), 'required'=>false, 'default'=>'',
                'hint'=>__('Text shown in before any input from the user'),
                'configuration'=>array('size'=>40, 'length'=>40),
            )),
        );
    }

    function hasSpecialSearch() {
        return false;
    }

    function validateEntry($value) {
        parent::validateEntry($value);
        $config = $this->getConfiguration();
        $validators = array(
            '' =>       null,
            'email' =>  array(array('Validator', 'is_email'),
                __('Enter a valid email address')),
            'phone' =>  array(array('Validator', 'is_phone'),
                __('Enter a valid phone number')),
            'ip' =>     array(array('Validator', 'is_ip'),
                __('Enter a valid IP address')),
            'number' => array('is_numeric', __('Enter a number')),
            'regex' => array(
                function($v) use ($config) {
                    $regex = $config['regex'];
                    return @preg_match($regex, $v);
                }, __('Value does not match required pattern')
            ),
        );
        // Support configuration forms, as well as GUI-based form fields
        $valid = $this->get('validator');
        if (!$valid) {
            $valid = $config['validator'];
        }
        if (!$value || !isset($validators[$valid]))
            return;
        $func = $validators[$valid];
        $error = $func[1];
        if ($config['validator-error'])
            $error = $config['validator-error'];
        if (is_array($func) && is_callable($func[0]))
            if (!call_user_func($func[0], $value))
                $this->_errors[] = $error;
    }
}

class PasswordField extends TextboxField {
    static $widget = 'PasswordWidget';

    function to_database($value) {
        return Crypto::encrypt($value, SECRET_SALT, $this->getFormName());
    }

    function to_php($value) {
        return Crypto::decrypt($value, SECRET_SALT, $this->getFormName());
    }
}

class TextareaField extends FormField {
    static $widget = 'TextareaWidget';

    function getConfigurationOptions() {
        return array(
            'cols'  =>  new TextboxField(array(
                'id'=>1, 'label'=>__('Width').' '.__('(chars)'), 'required'=>true, 'default'=>40)),
            'rows'  =>  new TextboxField(array(
                'id'=>2, 'label'=>__('Height').' '.__('(rows)'), 'required'=>false, 'default'=>4)),
            'length' => new TextboxField(array(
                'id'=>3, 'label'=>__('Max Length'), 'required'=>false, 'default'=>0)),
            'html' => new BooleanField(array(
                'id'=>4, 'label'=>__('HTML'), 'required'=>false, 'default'=>true,
                'configuration'=>array('desc'=>__('Allow HTML input in this box')))),
            'placeholder' => new TextboxField(array(
                'id'=>5, 'label'=>__('Placeholder'), 'required'=>false, 'default'=>'',
                'hint'=>__('Text shown in before any input from the user'),
                'configuration'=>array('size'=>40, 'length'=>40),
            )),
        );
    }

    function hasSpecialSearch() {
        return false;
    }

    function display($value) {
        $config = $this->getConfiguration();
        if ($config['html'])
            return Format::safe_html($value);
        else
            return nl2br(Format::htmlchars($value));
    }

    function searchable($value) {
        $value = preg_replace(array('`<br(\s*)?/?>`i', '`</div>`i'), "\n", $value);
        $value = Format::htmldecode(Format::striptags($value));
        return Format::searchable($value);
    }

    function export($value) {
        return (!$value) ? $value : Format::html2text($value);
    }

    function parse($value) {
        $config = $this->getConfiguration();
        if ($config['html'])
            return Format::sanitize($value);
        else
            return $value;
    }

}

class PhoneField extends FormField {
    static $widget = 'PhoneNumberWidget';

    function getConfigurationOptions() {
        return array(
            'ext' => new BooleanField(array(
                'label'=>__('Extension'), 'default'=>true,
                'configuration'=>array(
                    'desc'=>__('Add a separate field for the extension'),
                ),
            )),
            'digits' => new TextboxField(array(
                'label'=>__('Minimum length'), 'default'=>7,
                'hint'=>__('Fewest digits allowed in a valid phone number'),
                'configuration'=>array('validator'=>'number', 'size'=>5),
            )),
            'format' => new ChoiceField(array(
                'label'=>__('Display format'), 'default'=>'us',
                'choices'=>array(''=>'-- '.__('Unformatted').' --',
                    'us'=>__('United States')),
            )),
        );
    }

    function hasSpecialSearch() {
        return false;
    }

    function validateEntry($value) {
        parent::validateEntry($value);
        $config = $this->getConfiguration();
        # Run validator against $this->value for email type
        list($phone, $ext) = explode("X", $value, 2);
        if ($phone && (
                !is_numeric($phone) ||
                strlen($phone) < $config['digits']))
            $this->_errors[] = __("Enter a valid phone number");
        if ($ext && $config['ext']) {
            if (!is_numeric($ext))
                $this->_errors[] = __("Enter a valid phone extension");
            elseif (!$phone)
                $this->_errors[] = __("Enter a phone number for the extension");
        }
    }

    function parse($value) {
        // NOTE: Value may have a legitimate 'X' to separate the number and
        // extension parts. Don't remove the 'X'
        $val = preg_replace('/[^\dX]/', '', $value);
        // Pass completely-incorrect string for validation error
        return $val ?: $value;
    }

    function toString($value) {
        $config = $this->getConfiguration();
        list($phone, $ext) = explode("X", $value, 2);
        switch ($config['format']) {
        case 'us':
            $phone = Format::phone($phone);
            break;
        }
        if ($ext)
            $phone.=" x$ext";
        return $phone;
    }
}

class BooleanField extends FormField {
    static $widget = 'CheckboxWidget';

    function getConfigurationOptions() {
        return array(
            'desc' => new TextareaField(array(
                'id'=>1, 'label'=>__('Description'), 'required'=>false, 'default'=>'',
                'hint'=>__('Text shown inline with the widget'),
                'configuration'=>array('rows'=>2)))
        );
    }

    function to_database($value) {
        return ($value) ? '1' : '0';
    }

    function parse($value) {
        return $this->to_php($value);
    }
    function to_php($value) {
        return $value ? true : false;
    }

    function toString($value) {
        return ($value) ? __('Yes') : __('No');
    }
}

class ChoiceField extends FormField {
    static $widget = 'ChoicesWidget';

    function getConfigurationOptions() {
        return array(
            'choices'  =>  new TextareaField(array(
                'id'=>1, 'label'=>__('Choices'), 'required'=>false, 'default'=>'',
                'hint'=>__('List choices, one per line. To protect against spelling changes, specify key:value names to preserve entries if the list item names change'),
                'configuration'=>array('html'=>false)
            )),
            'default' => new TextboxField(array(
                'id'=>3, 'label'=>__('Default'), 'required'=>false, 'default'=>'',
                'hint'=>__('(Enter a key). Value selected from the list initially'),
                'configuration'=>array('size'=>20, 'length'=>40),
            )),
            'prompt' => new TextboxField(array(
                'id'=>2, 'label'=>__('Prompt'), 'required'=>false, 'default'=>'',
                'hint'=>__('Leading text shown before a value is selected'),
                'configuration'=>array('size'=>40, 'length'=>40),
            )),
            'multiselect' => new BooleanField(array(
                'id'=>1, 'label'=>'Multiselect', 'required'=>false, 'default'=>false,
                'configuration'=>array(
                    'desc'=>'Allow multiple selections')
            )),
        );
    }

    function parse($value) {
        return $this->to_php($value ?: null);
    }

    function to_database($value) {
        if (!is_array($value)) {
            $choices = $this->getChoices();
            if (isset($choices[$value]))
                $value = array($value => $choices[$value]);
        }
        if (is_array($value))
            $value = JsonDataEncoder::encode($value);

        return $value;
    }

    function to_php($value) {
        if (is_string($value))
            $array = JsonDataParser::parse($value) ?: $value;
        else
            $array = $value;
        $config = $this->getConfiguration();
        if (is_array($array) && !$config['multiselect'] && count($array) < 2) {
            reset($array);
            return key($array);
        }
        return $array;
    }

    function toString($value) {
        $selection = $this->getChoice($value);
        return is_array($selection) ? implode(', ', array_filter($selection))
            : (string) $selection;
    }

    function getChoice($value) {

        $choices = $this->getChoices();
        $selection = array();
        if ($value && is_array($value)) {
            $selection = $value;
        } elseif (isset($choices[$value]))
            $selection[] = $choices[$value];
        elseif ($this->get('default'))
            $selection[] = $choices[$this->get('default')];

        return $selection;
    }

    function getChoices($verbose=false) {
        if ($this->_choices === null || $verbose) {
            // Allow choices to be set in this->ht (for configurationOptions)
            $this->_choices = $this->get('choices');
            if (!$this->_choices) {
                $this->_choices = array();
                $config = $this->getConfiguration();
                $choices = explode("\n", $config['choices']);
                foreach ($choices as $choice) {
                    // Allow choices to be key: value
                    list($key, $val) = explode(':', $choice);
                    if ($val == null)
                        $val = $key;
                    $this->_choices[trim($key)] = trim($val);
                }
                // Add old selections if nolonger available
                // This is necessary so choices made previously can be
                // retained
                $values = ($a=$this->getAnswer()) ? $a->getValue() : array();
                if ($values && is_array($values)) {
                    foreach ($values as $k => $v) {
                        if (!isset($this->_choices[$k])) {
                            if ($verbose) $v .= ' (retired)';
                            $this->_choices[$k] = $v;
                        }
                    }
                }
            }
        }
        return $this->_choices;
     }
}

class DatetimeField extends FormField {
    static $widget = 'DatetimePickerWidget';

    function to_database($value) {