<?php

namespace WPML\ST\Batch\Translation;

use WPML\Collect\Support\Traits\Macroable;
use WPML\FP\Fns;
use WPML\FP\Relation;
use function WPML\FP\curryN;
use function WPML\FP\invoke;
use function WPML\FP\pipe;

/**
 * Class Convert
 * @package WPML\ST\Batch\Translation
 * @method static callable|array toBatchElements( ...$getBatchId, ...$setBatchRecord, ...$elements, ...$basketName ) :: ( string → int ) → ( int → int → string ) → [WPML_TM_Translation_Batch_Element] → string → [WPML_TM_Translation_Batch_Element]
 */
class Convert {

	use Macroable;

	public static function init() {

		self::macro( 'toBatchElements', curryN( 4, function ( $getBatchId, $setBatchRecord, $elements, $basketName ) {

			// $isString :: WPML_TM_Translation_Batch_Element → bool
			$isString = pipe( invoke( 'get_element_type' ), Relation::equals( 'string' ) );

			list( $stringElements, $otherElements ) = wpml_collect( $elements )->partition( $isString );

			$makeBatchPerLanguage = function ( \WPML_TM_Translation_Batch_Element $element ) use ( $getBatchId, $setBatchRecord, $basketName ) {
				$makeBatchElement = function ( $action, $lang ) use ( $element, $getBatchId, $setBatchRecord, $basketName ) {
					$batchId = $getBatchId( $basketName . '-' . $lang );

					$setBatchRecord( $batchId, $element->get_element_id(), $element->get_source_lang() );

					return Fns::makeN( 5, 'WPML_TM_Translation_Batch_Element',
							$batchId,
							'st-batch',
							$element->get_source_lang(),
							[ $lang => $action ],
							[]
					);
				};

				return Fns::map( $makeBatchElement, $element->get_target_langs() );
			};

			$stringElements = $stringElements->map( $makeBatchPerLanguage )
			                                 ->flatten()
			                                 ->unique( invoke( 'get_target_langs' )  );

			return $otherElements->merge( $stringElements )
			                     ->toArray();
		} ) );


	}
}

Convert::init();