icsbuilder.php

<?php
namespace Bitrix\Calendar\ICal;
 
use Bitrix\Main;
use \Bitrix\Main\Type\DateTime;
 
class IcsBuilder {
    //const DT_FORMAT = 'Ymd\THis\Z';
    const
        PRODID = '-//Bitrix//Bitrix Calendar//EN',
        DATE_FORMAT = 'Ymd',
        DATETIME_FORMAT = 'Ymd\THis';
 
    protected
        $fullDayMode = false,
        $organizer,
        $timezoneFrom,
        $timezoneTo,
        $attendees = [],
        $properties = [];
 
    private
        $availableProperties = [
        'summary',
        'description',
        'dtstart',
        'dtend',
        'dtstamp',
        'location',
        'url',
        'alarm',
        'transp',
        'status',
        'uid',
        'attendee',
        'created',
        'last-modified',
        'sequence',
        'transp'
    ];
    private static
        $METHOD = 'REQUEST';
 
 
    public function __construct($properties = [], $config = [])
    {
        $this->setProperties($properties);
        $this->setConfig($config);
    }
 
    public function setProperties($properties)
    {
        if (is_array($properties))
        {
            foreach ($properties as $key => $value)
            {
                if (in_array($key, $this->availableProperties) && !empty($value))
                {
                    $this->properties[$key] = $this->prepareValue($value, $key);
                }
            }
        }
    }
 
    public function setConfig($config)
    {
        if (is_array($config))
        {
            if (isset($config['timezoneFrom']))
            {
                $this->timezoneFrom = $config['timezoneFrom'];
            }
            if (isset($config['timezoneTo']))
            {
                $this->timezoneTo = $config['timezoneTo'];
            }
        }
    }
 
    public function setFullDayMode($value)
    {
        $this->fullDayMode = $value;
    }
 
    public function setOrganizer($name, $email, $phone)
    {
        $this->organizer = ['name' => $name, 'email' => $email, 'phone' => $phone];
    }
 
    public function setAttendees($attendeeDataList = [])
    {
        if (is_array($attendeeDataList))
        {
            foreach($attendeeDataList as $attendeeData)
            {
                $this->attendees[] = $attendeeData;
            }
        }
    }
 
    public function render()
    {
        return implode("\r\n", $this->buildBody());
    }
 
    private function buildBody()
    {
        // Build ICS properties - add header
        $ics_props = [
            'BEGIN:VCALENDAR',
            'PRODID:'.self::PRODID,
            'VERSION:2.0',
            'CALSCALE:GREGORIAN',
            'METHOD:'.self::$METHOD,
            'BEGIN:VEVENT'
        ];
 
        $props = [];
 
        // Add organizer field
        if (isset($this->organizer['email']))
        {
            $props[self::formatOrganizerKey($this->organizer)] = self::formatEmailValue($this->organizer['email']);
        }
        else if (isset($this->organizer['phone']))
        {
            $props[self::formatOrganizerKey($this->organizer)] = self::formatPhoneValue($this->organizer['phone']);
        }
 
        // Add attendees
        if (is_array($this->attendees))
        {
            foreach($this->attendees as $k => $attendee)
            {
                $props[self::formatAttendeeKey($attendee)] = self::formatEmailValue($attendee['email']);
            }
        }
 
        // Build ICS properties - add header
        foreach($this->properties as $k => $v)
        {
            if ($k === 'dtstamp')
            {
                $props['DTSTAMP'] = self::formatDateTimeValue($v);
                continue;
            }
            if ($k === 'url' )
            {
                $props['URL;VALUE=URI'] = $v;
            }
            else if ($k === 'dtstart' || $k === 'dtend')
            {
                if ($this->fullDayMode)
                {
                    $props[mb_strtoupper($k).';VALUE=DATE'] = self::formatDateValue($v);
                }
                else
                {
                    $tzid = ($k === 'dtstart') ? $this->timezoneFrom : $this->timezoneTo;
                    $props[mb_strtoupper($k).';TZID='.$tzid] = self::formatDateTimeValue($v);
                }
            }
            else
            {
                $props[mb_strtoupper($k)] = $v;
            }
        }
 
        // Append properties
        foreach ($props as $k => $v)
        {
            if ($k !== 'ALARM')
            {
                $ics_props[] = "$k:$v";
            }
            else
            {
                $ics_props[] = 'BEGIN:VALARM';
                $ics_props[] = 'TRIGGER:-PT' . $props['ALARM'];
                $ics_props[] = 'ACTION:DISPLAY';
                $ics_props[] = 'END:VALARM';
            }
        }
 
        // Build ICS properties - add footer
        $ics_props[] = 'END:VEVENT';
        $ics_props[] = 'END:VCALENDAR';
 
        return $ics_props;
    }
 
    private function prepareValue($val, $key = false)
    {
        switch($key)
        {
//          case 'dtstamp':
//          case 'dtstart':
//          case 'dtend':
//              $val = $this->formatDateValue($val);
//              break;
            default:
                $val = $this->escapeString($val);
        }
        return $val;
    }
 
    private static function formatDateValue($timestamp)
    {
        $dt = new \DateTime();
        $dt->setTimestamp($timestamp);
        return $dt->format(self::DATE_FORMAT);
    }
 
    private static function formatDateTimeValue($timestamp)
    {
        $dt = new \DateTime();
        if ($timestamp)
        {
            $dt->setTimestamp($timestamp);
        }
        return $dt->format(self::DATETIME_FORMAT);
    }
 
    private static function formatEmailValue($email)
    {
        return 'mailto:'.$email;
    }
 
    private static function formatPhoneValue($phone): string
    {
        return 'tel:'.$phone;
    }
 
 
    private static function formatAttendeeKey($attendee)
    {
        $key = 'ATTENDEE';
        $key .= ';CUTYPE=INDIVIDUAL';
        //$key .= ';PARTSTAT=ACCEPTED'; // NEEDS-ACTION
        $key .= ';RSVP=TRUE';
        $key .= ';CN='.$attendee['email'];
        return $key;
    }
 
    private static function formatOrganizerKey($organizer)
    {
        $key = 'ORGANIZER';
        if ($organizer['name'])
        {
            $key .= ';CN='.$organizer['name'];
        }
        return $key;
    }
 
    private static function escapeString($str)
    {
        return preg_replace('/([\,;])/','\\\$1', $str);
    }
}