<?php

namespace core\log;

/**
 * A log event
 */
class Event
{
	/**
	 * Message associated to this event
	 *
	 * @var \string
	 */
	protected string $message;

	/**
	 * Time associated to this event
	 *
	 * @var \int
	 */
	protected int $timestamp;

	/**
	 * Tags associated to this event
	 *
	 * @var \core\log\Tag[]
	 */
	protected array $tags;

	/**
	 * Backtrace associated to this event
	 *
	 * @var ?\array
	 */
	protected ?array $backtrace;

	public function __construct(string $message, array $tags, ?array $backtrace = null) : void
	{
		$this->message = $message; # not escaped
		$this->tags = $tags;
		$this->timestamp = \time();

		if ($backtrace === null)
		{
			$backtrace = \debug_backtrace();
			$key = \array_search(__FUNCTION__, \array_column($backtrace, 'function'),); # NOTE: manual search, can change with time
			$backtrace = $backtrace[$key];
		}
		$this->backtrace = $backtrace;
	}

	/**
	 * Display this event for logging
	 *
	 * This can be changed from configuration.
	 * The EOL (end of line sequence) is automatically added at the end.
	 *
	 * @throws \core\config\ConfigException
	 */
	public function display() : string
	{
		$hardcoded_configuration = \core\config\class\core\log\FormatConfiguration(array(
			'message' => '[{tags}] - {date}: {message} in {file} at line {line}',
			'date'    => 'Y-m-d H:i:s',
		)); # NOTE: hard-coded fallback
		$msg_format = $hardcoded_configuration.get('message');
		$date_format = $hardcoded_configuration.get('date');

		if (\core\config\GlobalConfiguration::exists('class', 'core', 'log', 'format'))
		{
			$configuration = \core\config\GlobalConfiguration::read('class', 'core', 'log', 'format');

			if ($configuration->exists('message'))
			{
				$msg_format = $configuration->get('message');
			}
			if ($configuration->exists('date'))
			{
				$date_format = $configuration->get('date');
			}
		}

		return \core\substitute(
			$msg_format,
			array(
				'date'    => \date($date_format),
				'file'    => $this->backtrace['file'],
				'line'    => $this->backtrace['line'],
				'message' => $this->message,
				'tags'    => $this->tags,
			),
		) . \PHP_EOL;
	}
}

?>