<?php
/**
 * Log levels.
 *
 * @package FormPilot
 * @since   1.0.0
 */

declare( strict_types = 1 );

namespace FormPilot\Logging;

if ( ! defined( 'ABSPATH' ) ) {
	exit;
}

/**
 * The severities a line can carry, and how they rank.
 *
 * A subset of PSR-3, kept to the four a plugin actually distinguishes between.
 * Adding the rest would mean asking a caller to choose between "critical" and
 * "alert" for the same event on different days.
 *
 * @since 1.0.0
 */
final class LogLevel {

	/**
	 * Nothing is written.
	 */
	public const OFF = 'off';

	/**
	 * Something failed and somebody needs to know.
	 */
	public const ERROR = 'error';

	/**
	 * Something was refused or worked around, and the site kept going.
	 */
	public const WARNING = 'warning';

	/**
	 * Something worth having a record of happened.
	 */
	public const INFO = 'info';

	/**
	 * Detail that is only useful while chasing a specific problem.
	 */
	public const DEBUG = 'debug';

	/**
	 * Returns the levels in order of how much they let through.
	 *
	 * @return array<string, int> Rank keyed by level. Higher means more verbose.
	 */
	public static function ranks(): array {
		return array(
			self::OFF     => 0,
			self::ERROR   => 1,
			self::WARNING => 2,
			self::INFO    => 3,
			self::DEBUG   => 4,
		);
	}

	/**
	 * Returns the labels for the settings screen.
	 *
	 * @return array<string, string> Translated labels keyed by level.
	 */
	public static function choices(): array {
		return array(
			self::OFF     => __( 'Off', 'devplugins-custom-form-builder' ),
			self::ERROR   => __( 'Errors only', 'devplugins-custom-form-builder' ),
			self::WARNING => __( 'Errors and warnings', 'devplugins-custom-form-builder' ),
			self::INFO    => __( 'Errors, warnings and activity', 'devplugins-custom-form-builder' ),
			self::DEBUG   => __( 'Everything (debug)', 'devplugins-custom-form-builder' ),
		);
	}

	/**
	 * Determines whether a line is severe enough to be written.
	 *
	 * @param string $level     Level of the line.
	 * @param string $threshold Level the site has asked for.
	 *
	 * @return bool True when the line should be kept.
	 */
	public static function allows( string $level, string $threshold ): bool {
		$ranks = self::ranks();

		$line  = $ranks[ $level ] ?? $ranks[ self::ERROR ];
		$limit = $ranks[ $threshold ] ?? $ranks[ self::OFF ];

		return $limit > 0 && $line <= $limit;
	}
}