<?php

    ### This section resides in the framework ###

    class Forms {
        /**
         * @var array Holds a list of forms.
         */
        protected static $forms=array();
        /**
         * Register form class name.
         * @param string $form Form class.
         */
        public static function register($form){
            self::$forms[]=$form;
        }
        /**
         * Prints out some stuff about loaded forms.
         */
        public function all(){
            echo count(self::$forms).' form(s): '.implode(', ',self::$forms);
        }
        /**
         * Returns a list of form classes.
         * Makes use of a custom function that loops through all register PHP classes and finds those that subclass a specific class.
         */
//3     public function forms(){
//3         return get_class_grandchildren('Form');
//3     }
    }

    class Form {
        /**
         * @var integer Form ID.
         */
        public $id=0;
        /**
         * @var string Form hint, must be overriden.
         */
        public static $hint='Form Template';
        /**
         * Returns form name (optionally overriden).
         * @return string The form's name.
         */
        public function name(){
            return 'Form'.$id;
        }
        /**
         * Returns the form's HTML code.
         * @return string The HTML code.
         */
        public function render(){
            return '';
        }
        /**
         * This is a hypothetical PHP magic method triggered when this class has been extended.
         * @param string $class The class name of the subclass that triggered this method.
         */
//2     public function __extended($class){
//2         Forms::register($class);
//2     }
    }


    ### This section resides in the framework template/plugin/3rdparty ###

    class LoginForm extends Form {
        public static $hint='Login Form Template';
        public function name(){
            return 'Login'.$this->id;
        }
        public function render(){
            return 'User: <input type="text" name="user"/> Pass: <input type="password" name="pass"/>';
        }
    }
//1 Forms::register('LoginForm');

    class RegisterForm extends Form {
        public static $hint='User Registration Form';
        public function name(){
            return 'Register'.$this->id;
        }
        public function render(){
            return 'User: <input type="text" name="user"/> Pass: <input type="password" name="pass"/> Email: <input type="text" name="email"/>';
        }
    }
//1 Forms::register('RegisterForm');