easyappointments/application/libraries/Availability.php
2020-11-12 14:15:12 +02:00

557 lines
21 KiB
PHP

<?php defined('BASEPATH') or exit('No direct script access allowed');
/* ----------------------------------------------------------------------------
* Easy!Appointments - Open Source Web Scheduler
*
* @package EasyAppointments
* @author A.Tselegidis <alextselegidis@gmail.com>
* @copyright Copyright (c) 2013 - 2020, Alex Tselegidis
* @license http://opensource.org/licenses/GPL-3.0 - GPLv3
* @link http://easyappointments.org
* @since v1.4.0
* ---------------------------------------------------------------------------- */
/**
* Class Availability
*
* Handles the availability generation of providers, based on their working plan and their schedule.
*/
class Availability {
/**
* @var CI_Controller
*/
protected $CI;
/**
* Availability constructor.
*/
public function __construct()
{
$this->CI =& get_instance();
$this->CI->load->model('providers_model');
$this->CI->load->model('secretaries_model');
$this->CI->load->model('secretaries_model');
$this->CI->load->model('admins_model');
$this->CI->load->model('appointments_model');
$this->CI->load->model('settings_model');
$this->CI->load->library('ics_file');
}
/**
* Get the available hours of a provider.
*
* @param string $date Selected date (Y-m-d).
* @param array $service Service record.
* @param array $provider Provider record.
* @param int|null $exclude_appointment_id Exclude an appointment from the availability generation.
*
* @return array
*
* @throws Exception
*/
public function get_available_hours($date, $service, $provider, $exclude_appointment_id = NULL)
{
$available_periods = $this->get_available_periods($date, $provider, $exclude_appointment_id);
$available_hours = $this->generate_available_hours($date, $service, $available_periods);
if ($service['attendants_number'] > 1)
{
$available_hours = $this->consider_multiple_attendants($date, $service, $provider);
}
return $this->consider_book_advance_timeout($date, $available_hours, $provider);
}
/**
* Get an array containing the free time periods (start - end) of a selected date.
*
* This method is very important because there are many cases where the system needs to know when a provider is
* available for an appointment. This method will return an array that belongs to the selected date and contains
* values that have the start and the end time of an available time period.
*
* @param string $date Select date string.
* @param array $provider Provider record.
* @param int|null $exclude_appointment_id Exclude an appointment from the availability generation.
*
* @return array Returns an array with the available time periods of the provider.
*
* @throws Exception
*/
public function get_available_periods(
$date,
$provider,
$exclude_appointment_id = NULL
)
{
// Get the service, provider's working plan and provider appointments.
$working_plan = json_decode($provider['settings']['working_plan'], TRUE);
// Get the provider's working plan exceptions.
$working_plan_exceptions = json_decode($provider['settings']['working_plan_exceptions'], TRUE);
$conditions = [
'id_users_provider' => $provider['id'],
];
// Sometimes it might be necessary to exclude an appointment from the calculation (e.g. when editing an
// existing appointment).
if ($exclude_appointment_id)
{
$conditions['id !='] = $exclude_appointment_id;
}
$appointments = $this->CI->appointments_model->get_batch($conditions);
// Find the empty spaces on the plan. The first split between the plan is due to a break (if any). After that
// every reserved appointment is considered to be a taken space in the plan.
$date_working_plan = $working_plan[strtolower(date('l', strtotime($date)))];
// Search if the $date is an custom availability period added outside the normal working plan.
if (isset($working_plan_exceptions[$date]))
{
$date_working_plan = $working_plan_exceptions[$date];
}
$periods = [];
if (isset($date_working_plan['breaks']))
{
$periods[] = [
'start' => $date_working_plan['start'],
'end' => $date_working_plan['end']
];
$day_start = new DateTime($date_working_plan['start']);
$day_end = new DateTime($date_working_plan['end']);
// Split the working plan to available time periods that do not contain the breaks in them.
foreach ($date_working_plan['breaks'] as $index => $break)
{
$break_start = new DateTime($break['start']);
$break_end = new DateTime($break['end']);
if ($break_start < $day_start)
{
$break_start = $day_start;
}
if ($break_end > $day_end)
{
$break_end = $day_end;
}
if ($break_start >= $break_end)
{
continue;
}
foreach ($periods as $key => $period)
{
$period_start = new DateTime($period['start']);
$period_end = new DateTime($period['end']);
$remove_current_period = FALSE;
if ($break_start > $period_start && $break_start < $period_end && $break_end > $period_start)
{
$periods[] = [
'start' => $period_start->format('H:i'),
'end' => $break_start->format('H:i')
];
$remove_current_period = TRUE;
}
if ($break_start < $period_end && $break_end > $period_start && $break_end < $period_end)
{
$periods[] = [
'start' => $break_end->format('H:i'),
'end' => $period_end->format('H:i')
];
$remove_current_period = TRUE;
}
if ($break_start == $period_start && $break_end == $period_end)
{
$remove_current_period = TRUE;
}
if ($remove_current_period)
{
unset($periods[$key]);
}
}
}
}
// Break the empty periods with the reserved appointments.
foreach ($appointments as $appointment)
{
foreach ($periods as $index => &$period)
{
$appointment_start = new DateTime($appointment['start_datetime']);
$appointment_end = new DateTime($appointment['end_datetime']);
if ($appointment_start >= $appointment_end)
{
continue;
}
$period_start = new DateTime($date . ' ' . $period['start']);
$period_end = new DateTime($date . ' ' . $period['end']);
if ($appointment_start <= $period_start && $appointment_end <= $period_end && $appointment_end <= $period_start)
{
// The appointment does not belong in this time period, so we will not change anything.
continue;
}
else
{
if ($appointment_start <= $period_start && $appointment_end <= $period_end && $appointment_end >= $period_start)
{
// The appointment starts before the period and finishes somewhere inside. We will need to break
// this period and leave the available part.
$period['start'] = $appointment_end->format('H:i');
}
else
{
if ($appointment_start >= $period_start && $appointment_end < $period_end)
{
// The appointment is inside the time period, so we will split the period into two new
// others.
unset($periods[$index]);
$periods[] = [
'start' => $period_start->format('H:i'),
'end' => $appointment_start->format('H:i')
];
$periods[] = [
'start' => $appointment_end->format('H:i'),
'end' => $period_end->format('H:i')
];
}
else if ($appointment_start == $period_start && $appointment_end == $period_end)
{
unset($periods[$index]); // The whole period is blocked so remove it from the available periods array.
}
else
{
if ($appointment_start >= $period_start && $appointment_end >= $period_start && $appointment_start <= $period_end)
{
// The appointment starts in the period and finishes out of it. We will need to remove
// the time that is taken from the appointment.
$period['end'] = $appointment_start->format('H:i');
}
else
{
if ($appointment_start >= $period_start && $appointment_end >= $period_end && $appointment_start >= $period_end)
{
// The appointment does not belong in the period so do not change anything.
continue;
}
else
{
if ($appointment_start <= $period_start && $appointment_end >= $period_end && $appointment_start <= $period_end)
{
// The appointment is bigger than the period, so this period needs to be removed.
unset($periods[$index]);
}
}
}
}
}
}
}
}
return array_values($periods);
}
/**
* Calculate the available appointment hours.
*
* Calculate the available appointment hours for the given date. The empty spaces
* are broken down to 15 min and if the service fit in each quarter then a new
* available hour is added to the "$available_hours" array.
*
* @param string $date Selected date (Y-m-d).
* @param array $service Service record.
* @param array $empty_periods Empty periods as generated by the "get_provider_available_time_periods"
* method.
*
* @return array Returns an array with the available hours for the appointment.
*
* @throws Exception
*/
protected function generate_available_hours(
$date,
$service,
$empty_periods
)
{
$available_hours = [];
foreach ($empty_periods as $period)
{
$start_hour = new DateTime($date . ' ' . $period['start']);
$end_hour = new DateTime($date . ' ' . $period['end']);
$interval = $service['availabilities_type'] === AVAILABILITIES_TYPE_FIXED ? (int)$service['duration'] : 15;
$current_hour = $start_hour;
$diff = $current_hour->diff($end_hour);
while (($diff->h * 60 + $diff->i) >= (int)$service['duration'])
{
$available_hours[] = $current_hour->format('H:i');
$current_hour->add(new DateInterval('PT' . $interval . 'M'));
$diff = $current_hour->diff($end_hour);
}
}
return $available_hours;
}
/**
* Get multiple attendants hours.
*
* This method will add the additional appointment hours whenever a service accepts multiple attendants.
*
* @param string $date Selected date (Y-m-d).
* @param array $service Service record.
* @param array $provider Provider record.
*
* @return array Returns the available hours array.
*
* @throws Exception
*/
protected function consider_multiple_attendants(
$date,
$service,
$provider
)
{
$unavailability_events = $this->CI->appointments_model->get_batch([
'is_unavailable' => TRUE,
'DATE(start_datetime)' => $date,
'id_users_provider' => $provider['id']
]);
$working_plan = json_decode($provider['settings']['working_plan'], TRUE);
$working_day = strtolower(date('l', strtotime($date)));
$working_hours = $working_plan[$working_day];
if ( ! $working_hours)
{
return [];
}
$periods = [
[
'start' => new DateTime($date . ' ' . $working_hours['start']),
'end' => new DateTime($date . ' ' . $working_hours['end'])
]
];
$periods = $this->remove_breaks($date, $periods, $working_hours['breaks']);
$periods = $this->remove_unavailability_events($periods, $unavailability_events);
$hours = [];
$interval_value = $service['availabilities_type'] == AVAILABILITIES_TYPE_FIXED ? $service['duration'] : '15';
$interval = new DateInterval('PT' . (int)$interval_value . 'M');
$duration = new DateInterval('PT' . (int)$service['duration'] . 'M');
foreach ($periods as $period)
{
$slot_start = clone $period['start'];
$slot_end = clone $slot_start;
$slot_end->add($duration);
while ($slot_end <= $period['end'])
{
// Check reserved attendants for this time slot and see if current attendants fit.
$appointment_attendants_number = $this->CI->appointments_model->get_attendants_number_for_period(
$slot_start,
$slot_end,
$service['id']
);
if ($appointment_attendants_number < $service['attendants_number'])
{
$hours[] = $slot_start->format('H:i');
}
$slot_start->add($interval);
$slot_end->add($interval);
}
}
return $hours;
}
/**
* Remove breaks from available time periods.
*
* @param string $selected_date Selected data (Y-m-d format).
* @param array $periods Time periods of the current date.
* @param array $breaks Breaks array for the current date.
*
* @return array Returns the available time periods without the breaks.
* @throws Exception
*/
public function remove_breaks($selected_date, $periods, $breaks)
{
if ( ! $breaks)
{
return $periods;
}
foreach ($breaks as $break)
{
$break_start = new DateTime($selected_date . ' ' . $break['start']);
$break_end = new DateTime($selected_date . ' ' . $break['end']);
foreach ($periods as &$period)
{
$period_start = $period['start'];
$period_end = $period['end'];
if ($break_start <= $period_start && $break_end >= $period_start && $break_end <= $period_end)
{
// left
$period['start'] = $break_end;
continue;
}
if ($break_start >= $period_start && $break_start <= $period_end && $break_end >= $period_start && $break_end <= $period_end)
{
// middle
$period['end'] = $break_start;
$periods[] = [
'start' => $break_end,
'end' => $period_end
];
continue;
}
if ($break_start >= $period_start && $break_start <= $period_end && $break_end >= $period_end)
{
// right
$period['end'] = $break_start;
continue;
}
if ($break_start <= $period_start && $break_end >= $period_end)
{
// break contains period
$period['start'] = $break_end;
continue;
}
}
}
return $periods;
}
/**
* Remove the unavailability entries from the available time periods of the selected date.
*
* @param array $periods Available time periods.
* @param array $unavailability_events Unavailability events of the current date.
*
* @return array Returns the available time periods without the unavailability events.
*
* @throws Exception
*/
public function remove_unavailability_events($periods, $unavailability_events)
{
foreach ($unavailability_events as $unavailability_event)
{
$unavailability_start = new DateTime($unavailability_event['start_datetime']);
$unavailability_end = new DateTime($unavailability_event['end_datetime']);
foreach ($periods as &$period)
{
$period_start = $period['start'];
$period_end = $period['end'];
if ($unavailability_start <= $period_start && $unavailability_end >= $period_start && $unavailability_end <= $period_end)
{
// left
$period['start'] = $unavailability_end;
continue;
}
if ($unavailability_start >= $period_start && $unavailability_start <= $period_end && $unavailability_end >= $period_start && $unavailability_end <= $period_end)
{
// middle
$period['end'] = $unavailability_start;
$periods[] = [
'start' => $unavailability_end,
'end' => $period_end
];
continue;
}
if ($unavailability_start >= $period_start && $unavailability_start <= $period_end && $unavailability_end >= $period_end)
{
// right
$period['end'] = $unavailability_start;
continue;
}
if ($unavailability_start <= $period_start && $unavailability_end >= $period_end)
{
// Unavailability contains period
$period['start'] = $unavailability_end;
continue;
}
}
}
return $periods;
}
/**
* Consider the book advance timeout and remove available hours that have passed the threshold.
*
* If the selected date is today, remove past hours. It is important include the timeout before booking
* that is set in the back-office the system. Normally we might want the customer to book an appointment
* that is at least half or one hour from now. The setting is stored in minutes.
*
* @param string $selected_date The selected date.
* @param array $available_hours Already generated available hours.
* @param array $provider Provider information.
*
* @return array Returns the updated available hours.
*
* @throws Exception
*/
protected function consider_book_advance_timeout($selected_date, $available_hours, $provider)
{
$provider_timezone = new DateTimeZone($provider['timezone']);
$book_advance_timeout = $this->CI->settings_model->get_setting('book_advance_timeout');
$threshold = new DateTime('+' . $book_advance_timeout . ' minutes', $provider_timezone);
foreach ($available_hours as $index => $value)
{
$available_hour = new DateTime($selected_date . ' ' . $value, $provider_timezone);
if ($available_hour->getTimestamp() <= $threshold->getTimestamp())
{
unset($available_hours[$index]);
}
}
$available_hours = array_values($available_hours);
sort($available_hours, SORT_STRING);
return array_values($available_hours);
}
}