<?php
/**
 * Email.inc.php
 * code by strangecode :: www.strangecode.com :: this document contains copyrighted information
 *
 * Easy email template usage.
 *
 * @author  Quinn Comendant <quinn@strangecode.com>
 * @version 1.0
-------------------------------------------------------------------------------------
// Example.
$email = new Email(array(
    'to' => array($frm['email'], 'q@lovemachine.local'),
    'from' => sprintf('%s <%s>', App::getParam('site_name'), App::getParam('site_email')),
    'subject' => 'Your account has been activated',
));
$email->setTemplate('email_registration_confirm.ihtml');
// $email->setString('Or you can pass your message body as a string, also with {VARIABLES}.');
$email->replace(array(
    'site_name' => App::getParam('site_name'),
    'site_url' => App::getParam('site_url'),
    'username' => $frm['username'],
    'password' => $frm['password1'],
));
if ($email->send()) {
    App::raiseMsg(sprintf(_("A confirmation email has been sent to %s."), $frm['email']), MSG_SUCCESS, __FILE__, __LINE__);
} else {
    App::logMsg(sprintf('Error sending confirmation email to address %s', $frm['email']), LOG_NOTICE, __FILE__, __LINE__);
}
-------------------------------------------------------------------------------------
 */
class Email {

    // Default parameters, to be overwritten by setParam() and read with getParam()
    var $_params = array(
        'to' => null,
        'from' => null,
        'subject' => null,
        'headers' => null,
        'regex' => null
    );

    // String that contains the email body.
    var $_template;

    // String that contains the email body after replacements.
    var $_template_replaced;

    /**
     * Constructor.
     *
     * @access  public
     * @param   array   $params     Array of object parameters.
     * @author  Quinn Comendant <quinn@strangecode.com>
     * @since   28 Nov 2005 12:59:41
     */
    function Email($params=null)
    {
        // The regex used in validEmail(). Set here instead of in the default _params above so we can use the concatination . dot.
        // This matches an email address as complex as:
        //      Bob Smith <bob&smith's/dep=sales!@smith-wick.ca.us> (Sales department)
        // ...and something as simple as:
        //      x@x.com
        $this->setParam(array('regex' => '/^(?:[^,@]*\s+|[^,@]*(<)|)'   // Display name
        . '((?:[^.<>\s@\",\[\]]+[^<>\s@\",\[\]])*[^.<>\s@\",\[\]]+)'    // Local-part
        . '@'                                                           // @
        . '((?:(\[)|[A-Z0-9]?)'                                         // Domain, first char
        . '(?(4)'                                                       // Domain conditional for if first domain char is [
        . '(?:[0-9]{1,3}\.){3}[0-9]{1,3}\]'                             // TRUE, matches IP address
        . '|'
        . '[.-]?(?:[A-Z0-9]+[-.])*(?:[A-Z0-9]+\.)+[A-Z]{2,6}))'         // FALSE, matches domain name
        . '(?(1)'                                                       // Comment conditional for if initial < exists
        . '(?:>\s*|>\s+\([^,@]+\)\s*)'                                  // TRUE, ensure ending >
        . '|'
        . '(?:|\s*|\s+\([^,@]+\)\s*))$/i'));                            // FALSE ensure there is no ending >

        if (isset($params)) {
            $this->setParam($params);
        }
    }

    /**
     * Set (or overwrite existing) parameters by passing an array of new parameters.
     *
     * @access public
     * @param  array    $params     Array of parameters (key => val pairs).
     */
    function setParam($params)
    {
        if (isset($params) && is_array($params)) {
            // Enforce valid email addresses.
            if (isset($params['to']) && !$this->validEmail($params['to'])) {
                $params['to'] = null;
            }
            if (isset($params['from']) && !$this->validEmail($params['from'])) {
                $params['from'] = null;
            }

            // Merge new parameters with old overriding only those passed.
            $this->_params = array_merge($this->_params, $params);
        } else {
            App::logMsg(sprintf('Parameters are not an array: %s', $params), LOG_ERR, __FILE__, __LINE__);
        }
    }

    /**
     * Return the value of a parameter, if it exists.
     *
     * @access public
     * @param string $param        Which parameter to return.
     * @return mixed               Configured parameter value.
     */
    function getParam($param)
    {
        if (isset($this->_params[$param])) {
            return $this->_params[$param];
        } else {
            App::logMsg(sprintf('Parameter is not set: %s', $param), LOG_NOTICE, __FILE__, __LINE__);
            return null;
        }
    }

    /**
     * Loads template from file to generate email body.
     *
     * @access  public
     * @param   string  $template   Filename of email template.
     * @author  Quinn Comendant <quinn@strangecode.com>
     * @since   28 Nov 2005 12:56:23
     */
    function setTemplate($template)
    {
        // Load file, using include_path.
        if (!$this->_template = file_get_contents($template, true)) {
            App::logMsg(sprintf('Email template file does not exist: %s', $template), LOG_ERR, __FILE__, __LINE__);
            $this->_template = null;
            $this->_template_replaced = null;
            return false;
        }
        // This could be a new template, so reset the _template_replaced.
        $this->_template_replaced = null;
        return true;
    }

    /**
     * Loads template from string to generate email body.
     *
     * @access  public
     * @param   string  $template   Filename of email template.
     * @author  Quinn Comendant <quinn@strangecode.com>
     * @since   28 Nov 2005 12:56:23
     */
    function setString($string)
    {
        // Load file, using include_path.
        if ('' == trim($string)) {
            App::logMsg(sprintf('Empty string provided.', null), LOG_ERR, __FILE__, __LINE__);
            $this->_template_replaced = null;
            return false;
        } else {
            $this->_template = $string;
            // This could be a new template, so reset the _template_replaced.
            $this->_template_replaced = null;
            return true;
        }
    }

    /**
     * Replace variables in template with argument data.
     *
     * @access  public
     * @param   array   $replacements   Array keys are the values to search for, array vales are the replacement values.
     * @author  Quinn Comendant <quinn@strangecode.com>
     * @since   28 Nov 2005 13:08:51
     */
    function replace($replacements)
    {
        // Ensure template exists.
        if (!isset($this->_template)) {
            App::logMsg(sprintf('Cannot replace variables, no template defined.', null), LOG_ERR, __FILE__, __LINE__);
            return false;
        }

        // Ensure replacements argument is an array.
        if (!is_array($replacements)) {
            App::logMsg(sprintf('Cannot replace variables, invalid replacements.', null), LOG_ERR, __FILE__, __LINE__);
            return false;
        }

        // Apply regex pattern to search elements.
        $search = array_keys($replacements);
        array_walk($search, create_function('&$v', '$v = "/{" . preg_quote($v) . "}/i";'));

        // Replacement values.
        $replace = array_values($replacements);

        // Search and replace all values at once.
        $this->_template_replaced = preg_replace($search, $replace, $this->_template);
    }

    /**
     * Send email using PHP's mail() function.
     *
     * @access  public
     * @param   string  $to
     * @param   string  $from
     * @param   string  $subject
     * @author  Quinn Comendant <quinn@strangecode.com>
     * @since   28 Nov 2005 12:56:09
     */
    function send($to=null, $from=null, $subject=null, $headers=null)
    {
        // Use arguments if provided.
        if (isset($to)) {
             $this->setParam(array('to' => $to));
        }
        if (isset($from)) {
             $this->setParam(array('from' => $from));
        }
        if (isset($subject)) {
             $this->setParam(array('subject' => $subject));
        }
        if (isset($headers)) {
             $this->setParam(array('headers' => $headers));
        }

        // Ensure required values exist.
        if (!isset($this->_params['subject'])) {
            App::logMsg(sprintf('Cannot send email to %s. SUBJECT not defined.', $this->_params['to']), LOG_ERR, __FILE__, __LINE__);
            return false;
        } else if (!isset($this->_template)) {
            App::logMsg(sprintf('Cannot send email: "%s". Template not set.', $this->_params['subject']), LOG_ERR, __FILE__, __LINE__);
            return false;
        } else if (!isset($this->_params['to'])) {
            App::logMsg(sprintf('Cannot send email: "%s". TO not defined.', $this->_params['subject']), LOG_NOTICE, __FILE__, __LINE__);
            return false;
        } else if (!isset($this->_params['from'])) {
            App::logMsg(sprintf('Cannot send email: "%s". FROM not defined.', $this->_params['subject']), LOG_ERR, __FILE__, __LINE__);
            return false;
        }

        // Wrap email text body, using _template_replaced if replacements have been used, or just a fresh _template if not.
        $final_body = wordwrap(isset($this->_template_replaced) ? $this->_template_replaced : $this->_template);

        // Ensure all placeholders have been replaced. Find anything with {...} characters.
        if (preg_match('/({[^}]+})/', $final_body, $unreplaced_match)) {
            App::logMsg(sprintf('Cannot send email. Variables left unreplaced in template: %s', (isset($unreplaced_match[1]) ? $unreplaced_match[1] : '')), LOG_ERR, __FILE__, __LINE__);
            return false;
        }

        // Final "to" header can have multiple addresses if in an array.
        $final_to = is_array($this->_params['to']) ? join(', ', $this->_params['to']) : $this->_params['to'];

        // From headers are custom headers.
        $headers = array('From' => $this->_params['from']);

        // Additional headers.
        if (isset($this->_params['headers']) && is_array($this->_params['headers'])) {
            $headers = array_merge($this->_params['headers'], $headers);
        }

        // Process headers.
        $final_headers = array();
        foreach ($headers as $key => $val) {
            $final_headers[] = sprintf('%s: %s', $key, $val);
        }
        $final_headers = join("\r\n", $final_headers);

        // This is the address where delivery problems are sent to. We must strip off everything except the local@domain part.
        $envelope_sender_header = sprintf('-f %s', preg_replace('/^.*<?([^\s@\[\]<>()]+\@[A-Za-z0-9.-]{1,}\.[A-Za-z]{2,5})>?$/iU', '$1', $this->_params['from']));

        // Check for mail header injection attacks.
        $full_mail_content = join("\n", array($final_to, $this->_params['subject'], $final_body, $final_headers, $envelope_sender_header));
        if (preg_match("/(Content-Type:|MIME-Version:|Content-Transfer-Encoding:|[\n\r]Bcc:|[\n\r]Cc:)/i", $full_mail_content)) {
            App::logMsg(sprintf('Mail header injection attack in content: %s', $full_mail_content), LOG_WARNING, __FILE__, __LINE__);
            sleep(3);
            return false;
        }

        // Ensure message was successfully accepted for delivery.
        if (mail($final_to, $this->_params['subject'], $final_body, $final_headers, $envelope_sender_header)) {
            App::logMsg(sprintf('Email successfully sent to %s', $final_to), LOG_DEBUG, __FILE__, __LINE__);
            return true;
        } else {
            App::logMsg(sprintf('Email failure with parameters: %s, %s, %s, %s', $final_to, $this->_params['subject'], str_replace("\r\n", '\r\n', $final_headers), $envelope_sender_header), LOG_NOTICE, __FILE__, __LINE__);
            return false;
        }
    }

    /**
     * Validates an email address based on the recommendations in RFC 3696.
     * Is more loose than restrictive, to allow the many valid variants of
     * email addresses while catching the most common mistakes. Checks an array too.
     * http://www.faqs.org/rfcs/rfc822.html
     * http://www.faqs.org/rfcs/rfc2822.html
     * http://www.faqs.org/rfcs/rfc3696.html
     * http://www.faqs.org/rfcs/rfc1035.html
     *
     * @access  public
     * @param   mixed  $email  Address to check, string or array.
     * @return  bool    Validity of address.
     * @author  Quinn Comendant <quinn@strangecode.com>
     * @since   30 Nov 2005 22:00:50
     */
    function validEmail($email)
    {
        // If an array, check values recursively.
        if (is_array($email)) {
            foreach ($email as $e) {
                if (!$this->validEmail($e)) {
                    return false;
                }
            }
            return true;
        } else {
            // To be valid email address must match regex and fit within the lenth constraints.
            if (preg_match($this->getParam('regex'), $email, $e_parts) && strlen($e_parts[2]) < 64 && strlen($e_parts[3]) < 255) {
                return true;
            } else {
                App::logMsg(sprintf('Invalid email: %s', $email), LOG_INFO, __FILE__, __LINE__);
                return false;
            }
        }
    }
}

?>