Trying to set up SMS reminders via my web application - php

Question

I am trying to have an SMS sent as a reminder to the users of my web application. I am not too familiar or good with cron jobs. I know that I have to set one up, I don't think that I did it effectively though.
I am not sure if my path is correct, how could I test that? Also, should I set it to every minute or should I set it to once a day. What is the difference?
Would this work if the path is correct?
<?php
//This was based upon http://glennstovall.com/blog/2013/01/07/writing-cron-jobs-and-command-line-scripts-in-codeigniter/ with modifications for Easy!Appointments by Craig Tucker, 7/18/2014.
class Reminders extends CI_Controller {
public function __construct() {
parent::__construct();
$this->load->library('email');
$this->load->library('session');
$this->load->model('settings_model');
$this->load->model('reminders_model');
// Set user's selected language.
if ($this->session->userdata('language')) {
$this->config->set_item('language', $this->session->userdata('language'));
$this->lang->load('translations', $this->session->userdata('language'));
} else {
$this->lang->load('translations', $this->config->item('language')); // default
}
}
public function index() {
if(!$this->input->is_cli_request()) {
echo "This script can only be accessed via the command line" . PHP_EOL;
return;
}
$d = 3; //Number of days out for the reminder
$timestamp = strtotime("+".$d." days");
$appointments = $this->reminders_model->get_days_appointments($timestamp);
$baseurl = $this->config->base_url();
$company_name = $this->settings_model->get_setting('company_name');
$appointment_link = $this->config->base_url().'index.php/appointments/index/';
if ($d == "1") {
$notice = "One more day until your appointment.";
} else {
$notice = $d." more days until your appointment.";
}
$msg = '';
if(!empty($appointments)) {
foreach($appointments as $appointment) {
$aptdatetime=date('D g:i a',strtotime($result["start_datetime"]));
$startdatetime=date('l, F j, Y, g:i a',strtotime($appointment->start_datetime));
$config['mailtype'] = 'text';
$this->email->initialize($config);
$this->email->set_newline("\r\n");
$this->email->to($appointment->customer_email);
if (!empty($appointment->customer_cellurl)){
$phone = $appointment->customer_phone_number;
$phone = preg_replace('/[^\dxX]/', '', $phone);
$this->email->bcc($phone.$appointment->customer_cellurl);
}
$this->email->from($appointment->provider_email, $company_name);
$this->email->subject($notice);
$msg .= $company_name."\r\n";
$msg .= "REMINDER: Your appointment with ".$appointment->provider_first_name." ".
$appointment->provider_last_name." is on ".$startdatetime."\r\n";
$msg .= "\r\n";
$msg .= "If you have had a good experience, let others know! Please review me at:\r\n";
$msg .= "www.healthgrades.com/review/XGVRC\r\n";
$msg .= "\r\n";
$msg .= "To edit, reschedule, or cancel your appointment please click the following link:\r\n";
$msg .= $appointment_link.$appointment->hash."\r\n";
$msg .= "\r\n";
$msg .="To attend your session on line, log in to www.craigtuckerlcsw.com and go to 'My Appointments'\r\n";
$this->email->message($msg);
$this->email->send();
$msg = "";
echo $this->email->print_debugger();
}
}
}
}
/* End of file reminders.php */
/* Location: ./application/controllers/cli/reminders.php */