<?php

namespace Wikimedia\ParamValidator\TypeDef;

use Wikimedia\ParamValidator\Callbacks;
use Wikimedia\ParamValidator\TypeDef;
use Wikimedia\ParamValidator\ValidationException;
use Wikimedia\Timestamp\ConvertibleTimestamp;
use Wikimedia\Timestamp\TimestampException;

/**
 * Type definition for timestamp types
 *
 * This uses the wikimedia/timestamp library for parsing and formatting the
 * timestamps.
 *
 * The result from validate() is a ConvertibleTimestamp by default, but this
 * may be changed by both a constructor option and a PARAM constant.
 *
 * ValidationException codes:
 *  - 'badtimestamp': The timestamp is not valid. No data, but the
 *    TimestampException is available via Exception::getPrevious().
 *  - 'unclearnowtimestamp': Non-fatal. The value is the empty string or "0".
 *    Use 'now' instead if you really want the current timestamp. No data.
 *
 * @since 1.34
 * @unstable
 */
class TimestampDef extends TypeDef {

	/**
	 * (string|int) Timestamp format to return from validate()
	 *
	 * Values include:
	 *  - 'ConvertibleTimestamp': A ConvertibleTimestamp object.
	 *  - 'DateTime': A PHP DateTime object
	 *  - One of ConvertibleTimestamp's TS_* constants.
	 *
	 * This does not affect the format returned by stringifyValue().
	 */
	const PARAM_TIMESTAMP_FORMAT = 'param-timestamp-format';

	/** @var string|int */
	protected $defaultFormat;

	/** @var int */
	protected $stringifyFormat;

	/**
	 * @param Callbacks $callbacks
	 * @param array $options Options:
	 *  - defaultFormat: (string|int) Default for PARAM_TIMESTAMP_FORMAT.
	 *    Default if not specified is 'ConvertibleTimestamp'.
	 *  - stringifyFormat: (int) Format to use for stringifyValue().
	 *    Default is TS_ISO_8601.
	 */
	public function __construct( Callbacks $callbacks, array $options = [] ) {
		parent::__construct( $callbacks );

		$this->defaultFormat = $options['defaultFormat'] ?? 'ConvertibleTimestamp';
		$this->stringifyFormat = $options['stringifyFormat'] ?? TS_ISO_8601;
	}

	public function validate( $name, $value, array $settings, array $options ) {
		// Confusing synonyms for the current time accepted by ConvertibleTimestamp
		if ( !$value ) {
			$this->callbacks->recordCondition(
				new ValidationException( $name, $value, $settings, 'unclearnowtimestamp', [] ),
				$options
			);
			$value = 'now';
		}

		try {
			$timestamp = new ConvertibleTimestamp( $value === 'now' ? false : $value );
		} catch ( TimestampException $ex ) {
			throw new ValidationException( $name, $value, $settings, 'badtimestamp', [], $ex );
		}

		$format = $settings[self::PARAM_TIMESTAMP_FORMAT] ?? $this->defaultFormat;
		switch ( $format ) {
			case 'ConvertibleTimestamp':
				return $timestamp;

			case 'DateTime':
				// Eew, no getter.
				return $timestamp->timestamp;

			default:
				return $timestamp->getTimestamp( $format );
		}
	}

	public function stringifyValue( $name, $value, array $settings, array $options ) {
		if ( !$value instanceof ConvertibleTimestamp ) {
			$value = new ConvertibleTimestamp( $value );
		}
		return $value->getTimestamp( $this->stringifyFormat );
	}

}