<?php

class ICalEvent
{
	// phpcs:disable Generic.Arrays.DisallowLongArraySyntax

	const HTML_TEMPLATE = '<p>%s: %s</p>';

	/**
	 * https://www.kanzaki.com/docs/ical/summary.html
	 *
	 * @var string
	 */
	public $summary;

	/**
	 * https://www.kanzaki.com/docs/ical/dtstart.html
	 *
	 * @var string
	 */
	public $dtstart;

	/**
	 * https://www.kanzaki.com/docs/ical/dtend.html
	 *
	 * @var string
	 */
	public $dtend;

	/**
	 * https://www.kanzaki.com/docs/ical/duration.html
	 *
	 * @var string
	 */
	public $duration;

	/**
	 * https://www.kanzaki.com/docs/ical/dtstamp.html
	 *
	 * @var string
	 */
	public $dtstamp;

	/**
	 * When the event starts, represented as a timezone-adjusted string
	 *
	 * @var string
	 */
	public $dtstart_tz;

	/**
	 * When the event ends, represented as a timezone-adjusted string
	 *
	 * @var string
	 */
	public $dtend_tz;

	/**
	 * https://www.kanzaki.com/docs/ical/uid.html
	 *
	 * @var string
	 */
	public $uid;

	/**
	 * https://www.kanzaki.com/docs/ical/created.html
	 *
	 * @var string
	 */
	public $created;

	/**
	 * https://www.kanzaki.com/docs/ical/lastModified.html
	 *
	 * @var string
	 */
	public $last_modified;

	/**
	 * https://www.kanzaki.com/docs/ical/description.html
	 *
	 * @var string
	 */
	public $description;

	/**
	 * https://www.kanzaki.com/docs/ical/location.html
	 *
	 * @var string
	 */
	public $location;

	/**
	 * https://www.kanzaki.com/docs/ical/sequence.html
	 *
	 * @var string
	 */
	public $sequence;

	/**
	 * https://www.kanzaki.com/docs/ical/status.html
	 *
	 * @var string
	 */
	public $status;

	/**
	 * https://www.kanzaki.com/docs/ical/transp.html
	 *
	 * @var string
	 */
	public $transp;

	/**
	 * https://www.kanzaki.com/docs/ical/organizer.html
	 *
	 * @var string
	 */
	public $organizer;

	/**
	 * https://www.kanzaki.com/docs/ical/attendee.html
	 *
	 * @var string
	 */
	public $attendee;

	/**
	 * Manage additional properties
	 *
	 * @var array<string, mixed>
	 */
	private $additionalProperties = array();

	/**
	 * Creates the Event object
	 *
	 * @param  array $data
	 * @return void
	 */
	public function __construct(array $data = array())
	{
		foreach ($data as $key => $value) {
			$variable = self::snakeCase($key);
			if (property_exists($this, $variable)) {
				$this->{$variable} = $this->prepareData($value);
			} else {
				$this->additionalProperties[$variable] = $this->prepareData($value);
			}
		}
	}

	/**
	 * Magic getter method
	 *
	 * @param string $additionalPropertyName
	 * @return mixed
	 */
	public function __get(string $additionalPropertyName)
	{
		if (array_key_exists($additionalPropertyName, $this->additionalProperties)) {
			return $this->additionalProperties[$additionalPropertyName];
		}

		return null;
	}

	/**
	 * Magic isset method
	 */
	public function __isset(string $name): bool
	{
		return is_null($this->$name) === false;
	}

	/**
	 * Prepares the data for output
	 *
	 * @param  mixed $value
	 * @return mixed
	 */
	protected function prepareData($value)
	{
		if (is_string($value)) {
			return stripslashes(trim(str_replace('\n', "\n", $value)));
		}

		if (is_array($value)) {
			return array_map(function ($value) {
				return $this->prepareData($value);
			}, $value);
		}

		return $value;
	}

	/**
	 * Returns Event data excluding anything blank
	 * within an HTML template
	 *
	 * @param  string $html HTML template to use
	 * @return string
	 */
	public function printData($html = self::HTML_TEMPLATE)
	{
		$data = array(
			'SUMMARY'       => $this->summary,
			'DTSTART'       => $this->dtstart,
			'DTEND'         => $this->dtend,
			'DTSTART_TZ'    => $this->dtstart_tz,
			'DTEND_TZ'      => $this->dtend_tz,
			'DURATION'      => $this->duration,
			'DTSTAMP'       => $this->dtstamp,
			'UID'           => $this->uid,
			'CREATED'       => $this->created,
			'LAST-MODIFIED' => $this->last_modified,
			'DESCRIPTION'   => $this->description,
			'LOCATION'      => $this->location,
			'SEQUENCE'      => $this->sequence,
			'STATUS'        => $this->status,
			'TRANSP'        => $this->transp,
			'ORGANISER'     => $this->organizer,
			'ATTENDEE(S)'   => $this->attendee,
		);

		// Remove any blank values
		$data = array_filter($data);

		$output = '';

		foreach ($data as $key => $value) {
			$output .= sprintf($html, $key, $value);
		}

		return $output;
	}

	/**
	 * Converts the given input to snake_case
	 *
	 * @param  string $input
	 * @param  string $glue
	 * @param  string $separator
	 * @return string
	 */
	protected static function snakeCase($input, $glue = '_', $separator = '-')
	{
		$input = preg_split('/(?<=[a-z])(?=[A-Z])/x', $input);
		$input = implode($glue, $input);
		$input = str_replace($separator, $glue, $input);

		return strtolower($input);
	}
}