form.php

<?php

namespace BestProject\Wordpress;

use BestProject\Wordpress\Object;

defined('ABSPATH') or die;

/**
 * Form class.
 */
class Form
{

    use Object;
    /**
     * Name of this form.
     *
     * @var    String
     */
    protected $name;

    /**
     * List of form fields.
     *
     * @var    Array
     */
    protected $fields;

    /**
     * Form method.
     *
     * @var    String
     */
    protected $method;

    /**
     * Array of form tag attributes.
     *
     * @var    Array
     */
    protected $attributes;

    /**
     * Recipient for this form data. It accepts a valid email, name of a form field
     * that holds the email or a PostType instance that should hold the data.
     * It also accepts array of those values.
     *
     * Form is processing the recipients and its input on construct if $recipient is not empty.
     *
     * @var    Mixed
     */
    protected $recipient;

    /**
     * Holds list of form errors (mostly validation).
     *
     * @var    Array
     */
    protected $errors = array();

    /**
     * Subject of an e-mail if there are e-mail recipipients for this form.
     *
     * @var    String
     */
    protected $mail_subject = '';

    /**
     * Sender e-mail if there are e-mail recipients for form.
     *
     * @var    String
     */
    protected $mail_sender = '';

    /**
     * Name of the sender if there are e-mail recipients for form.
     *
     * @var    String
     */
    protected $mail_sender_name = '';

    /**
     * Create new Form instance.
     *
     * @param    String    $name                Name of this form.
     * @param    Array    $fields                List of form fields.
     * @param    Mixed    $recipient            Recipient for this form data. It accepts a valid email, name of a form field that holds the email or a PostType instance that should hold the data. It also accepts array of those values.
     * @param    String    $mail_subject        Subject for a mail if there are e-mail recipients in this form.
     * @param    String    $mail_sender_name    Name of a sender if there are e-mail recipients in this form.
     */
    public function __construct($name, Array $fields, $recipient = array(),
                                $mail_subject = '', $mail_sender = '',
                                $mail_sender_name = '')
    {

        // Add fields using its name as array key so we can access them easly later
        foreach ($fields AS $field) {
            $this->fields[$field->get('name')] = $field;
        }

        // Set default params
        $this->set('name', $name);
        $this->set('recipient', $recipient);
        $this->set('mail_subject', $mail_subject);
        $this->set('mail_sender', $mail_sender);
        $this->set('mail_sender_name', $mail_sender_name);

        // Set basic form attributes
        $this->setAttribute('method', 'post');
        $this->setAttribute('id', 'form-'.$name);
        $this->setAttribute('action',
            filter_input(INPUT_SERVER, 'REQUEST_URI').'#form-'.$name);
    }

    /**
     * Get a render list of form attributes like name, action, method.
     */
    public function renderFormAttributes()
    {
        $html = '';
        foreach ($this->attributes AS $attribute => $value) {
            $html .= $attribute.'="'.htmlentities($value).'" ';
        }

        return trim($html);
    }

    /**
     * Set a form tag attribute and return form instance for chaining.
     *
     * @param    String    $name    Attribute name.
     * @param    String    $value    Attribute value.
     */
    public function setAttribute($name, $value)
    {
        $this->attributes[$name] = $value;

        return $this;
    }

    /**
     * Return selected form attribute.
     *
     * @param    String    $name        Attribute name to return.
     * @param    Mixed    $default    Default value.
     * @return String
     */
    public function getAttribute($name, $default = '')
    {
        if (isset($this->attributes[$name])) {
            return $this->attributes[$name];
        } else {
            return $default;
        }
    }

    /**
     * Render a selected form field.
     *
     * @param    String    $name    Name of a field to render.
     * @return    String
     */
    public function renderField($name)
    {
        if (isset($this->fields[$name])) {
            return $this->fields[$name]->render();
        } else {
            if (defined('WP_DEBUG') AND WP_DEBUG) {
                throw new \Exception('Field '.$name.' was not found in this form.',
                500);
            }
        }
    }

    /**
     * Does this form validate? Check each field if it validates.
     *
     * @return    Boolean
     */
    public function validate()
    {

        // Validate each form field.
        $validates = true;
        foreach ($this->fields AS $field) {

            // Get validation result
            $validate_result = $field->validate();

            // If this field did not validate add its error message to form errors.
            if ($validate_result !== true) {

                $this->errors[] = $validate_result;
                $validates      = false;
            }
        }

        return $validates;
    }

    /**
     * Return errors list.
     *
     * @return    Array
     */
    public function getErrors()
    {
        return $this->errors;
    }

    /**
     * Process form input. Returns:
     * TRUE: If every recipient was processed correctly.
     * FALSE: If there was a single error while processing the recipients.
     * NULL: If there is no data to process.
     */
    public function processInput()
    {

        // Is there anything to process
        if (strtoupper($this->attributes['method']) == 'POST' AND empty($_POST)) {
            return;
        } elseif (strtoupper($this->attributes['method']) == 'GET' AND empty($_GET)) {
            return;
        }

        // Check if form validates
        if (!$this->validate()) {
            return false;
        }

        // Holding recipient processing results
        $results = array();

        // If there is a list providing recipients
        if (is_array($this->recipient)) {

            // Process each recipient
            foreach ($this->recipient AS $recipient) {
                $results[] = $this->processRecipient($recipient);
            }

            // its a single recipient
        } else {
            $results[] = $this->processRecipient($this->recipient);
        }

        // Was there any error while processing the recipients list?
        if (in_array(false, $results)) {
            return false;

            // All recipients processed without an error
        } elseif (!empty($results)) {
            return true;
        }
    }

    /**
     * Process selected recipient.
     *
     * @param    $recipient
     */
    private function processRecipient($recipient)
    {

        // Its a PostType
        $className = '\\BestProject\\Wordpress\\PostType';
        if (is_object($recipient) AND ( $recipient instanceof $className)) {
            // TODO: Process PostType as a recipient
            //

            // Is an object but wrong type
        } elseif (is_object($recipient)) {
            throw new \Exception('Wrong object provided as a form recipient.');

            // String provided
        } elseif (is_string($recipient)) {

            $recipient = (string) $recipient;

            // Is this a valid e-mail
            $is_valid_email = !(filter_var($recipient, FILTER_VALIDATE_EMAIL) === false);

            // Is this not a valid email but a valid form field name that holds an e-mail
            if (!$is_valid_email AND isset($this->fields[$recipient]) AND ! (filter_var($this->fields[$recipient]->getSaveData(),
                    FILTER_VALIDATE_EMAIL) === false)) {
                $recipient      = $this->fields[$recipient]->getSaveData();
                $is_valid_email = true;
            } elseif (!$is_valid_email) {
                $is_valid_email = false;
            }

            // Send e-mail
            if ($is_valid_email AND $this->sendEmail($recipient)) {
                return true;
            } else {

                $this->errors[] = Language::_('FORM_COULD_NOT_SEND_EMAIL');

                return false;
            }
        }
    }

    /**
     * Send e-mail with form input to the selected e-mail address.
     *
     * @param    String    $recipient_email    Recipient e-mail address.
     * @return    Boolean
     */
    private function sendEmail($recipient_email)
    {

        // Generate an e-mail template file
        $path = get_template_directory().'/template-parts/emails/'.$this->name.'.php';

        // Default e-mail options
        $mail_subject     = $this->mail_subject;
        $mail_sender      = $this->mail_sender;
        $mail_sender_name = $this->mail_sender_name;
        $mail_recipient   = $recipient_email;

        // If e-mail template file exists
        if (file_exists($path)) {

            // Generate e-mail body
            ob_start();
            require $path;
            $mail_body = ob_get_clean();

            // There is no e-mail template. Use default view
        } else {

            // List of field types that should not be processed
            $hide_fields = array(
                '\\BestProject\Wordpress\\Form\\Field\\Submit',
                '\\BestProject\Wordpress\\Form\\Field\\Button',
            );

            $mail_body = '';
            /* @var $field Field */
            foreach ($this->fields AS $field) {

                if (!in_array(get_class($field), $hide_fields)) {
                    $mail_body .= '<div>';
                    $mail_body .= '<h4>'.$field->get('label').'</h4>';
                    $mail_body .= $field->getSaveData();
                    $mail_body .= '</div>'."\n";
                }
            }
        }

        // If any of required parameters is missing, return failure
        if (empty($mail_subject) OR empty($mail_sender) OR empty($mail_sender_name) OR empty($mail_body)) {
            return false;

            // We have all the data, so send the message
        } else {
            $headers[] = 'MIME-Version: 1.0';
            $headers[] = 'Content-type: text/html; charset=utf-8';

            // Add sender name if provided
            if (!empty($mail_sender_name)) {
                $headers[] = 'From: '.$mail_sender_name.' <'.$mail_sender.'>';

                // No sender name, just set an e-mail address
            } else {
                $headers[] = 'From: '.$mail_sender;
            }

            // Send email and return its
            return mail($mail_recipient, $mail_subject, $mail_body,
                implode("\r\n", $headers));
        }

        return true;
    }

    /**
     * Returns an instance of a selected form field.
     *
     * @param    String            $name    Name of a field to return.
     * @return    Field|Boolean
     */
    public function &getField($name)
    {

        // If field with this name was set in this form, return its reference.
        if (isset($this->fields[$name])) {
            return $this->fields[$name];
        }

        return false;
    }
}