form_helper.php

<?php

/**
 *
 */
class FormHelper
{
    /**
     *  Controla os indices de metadados
     *  @var int
     */
    private static $index = 0;

    /**
     * Cria inputs do formulário
     *
     * @param mixed $type
     * @param mixed $name
     * @param bool $value
     * @param bool $attributes
     * @return string
     */
    public static function input($type, $name, $value = null, $attributes = array())
    {
        $html  = static::hiddenMeta($name);
        $name = 'extras['.static::$index.'][dado]';
        $attributes = array_merge(compact('type', 'name', 'value'), $attributes);
        $html .= '<input '.static::attributify($attributes).'/>' . PHP_EOL;
        static::$index++;

        return $html;
    }

    /**
     * Inprime o input hidden com o nome do meta.
     *
     * @param  string $name
     * @return string
     */
    public static function hiddenMeta($name)
    {
        return '<input type="hidden" name="extras['.static::$index.'][meta]" value="'.static::escape($name).'"/>'.PHP_EOL;
    }

    /**
     * Cria o text input
     *
     * @param  mixed  $name
     * @param  mixed  $value
     * @param  array  $attributes
     * @return string
     */
    public static function text($name, $value = null, $attributes = array())
    {
        return static::input('text', $name, $value, $attributes);
    }

    /**
     * Cria checkbox input
     *
     * @param  mixed  $name
     * @param  mixed  $value
     * @param  array  $attributes
     * @return string
     */
    public static function checkbox($name, $value = null, $attributes = array())
    {
        return static::input('checkbox', $name, $value, $attributes);
    }

    /**
     * Transforma o array de attributes em uma string
     *
     * @param  array  $attributes
     * @return string
     */
    public static function attributify($attributes = array())
    {
        $html = '';
        foreach ($attributes as $key => $value) {
            if (is_numeric($key)) {
                $key = $value;
            }

            if (!is_null($value)) {
                $html .= $key.'="'.static::escape($value).'" ';
            }
        }

        return $html;
    }

    /**
     * Escapa HTML entities na string.
     *
     * @param  mixed  $value
     * @return string
     */
    public static function escape($value)
    {
        return htmlentities($value, ENT_QUOTES, 'UTF-8', false);
    }

}