<?php
/**
 * Test data: product categories.
 *
 * @package AdminPowerups
 */

namespace SmartWP\AdminPowerups\Modules\TestData\Make;

use SmartWP\AdminPowerups\Modules\TestData\Data\Random;
use SmartWP\AdminPowerups\Modules\TestData\Marker;

defined( 'ABSPATH' ) || exit;

/**
 * One parent category per batch ("Test data – {label}") and four children. Slugs start with
 * Marker::slug() (a salted token, never the batch ID). The marker is written by a `created_term`
 * callback inside wp_insert_term(), so the term and its marker come in the same call; a step that
 * died before signing finds its term again by that secret slug.
 *
 * @since 1.0.0
 */
final class Terms {

	/**
	 * Children per batch.
	 */
	const CHILDREN = 4;

	/**
	 * Batch of the term being inserted (read by mark()).
	 *
	 * @var string
	 */
	private static $batch = '';

	/**
	 * Make the batch's categories (or find them again after a resumed step).
	 *
	 * @since 1.0.0
	 * @param Context $ctx Context.
	 * @return array{parent: int, children: int[], made: int}
	 */
	public static function make( Context $ctx ): array {
		$random = Random::for( $ctx->batch, 'terms', 0 );
		$made   = 0;
		$slug   = Marker::slug( $ctx->batch );
		/* translators: %s: batch label. */
		$parent = self::term( sprintf( __( 'Test data – %s', 'admin-powerups-for-woocommerce' ), $ctx->label ), $slug, 0, $ctx, $made );
		$names  = $ctx->words['categories'];
		$picked = array();
		for ( $i = 0; $i < self::CHILDREN && $names; $i++ ) {
			$name     = (string) $random->pick( $names );
			$names    = array_values( array_diff( $names, array( $name ) ) );
			$picked[] = $name;
		}
		$children = array();
		if ( $parent ) {
			foreach ( $picked as $i => $name ) {
				$id = self::term( $name, $slug . '-' . ( $i + 1 ), $parent, $ctx, $made );
				if ( $id ) {
					$children[] = $id;
				}
			}
		}
		return array(
			'parent'   => $parent,
			'children' => $children ? $children : ( $parent ? array( $parent ) : array() ),
			'made'     => $made,
		);
	}

	/**
	 * `created_term` (only inside our wp_insert_term()): the marker, in the same call.
	 *
	 * @since 1.0.0
	 * @param mixed $term_id  Term ID.
	 * @param mixed $tt_id    Term taxonomy ID.
	 * @param mixed $taxonomy Taxonomy.
	 * @return void
	 */
	public static function mark( $term_id, $tt_id = 0, $taxonomy = '' ): void {
		if ( 'product_cat' === $taxonomy && '' !== self::$batch ) {
			update_term_meta( (int) $term_id, Marker::META, self::$batch );
		}
	}

	/**
	 * Insert one category, or reuse ours with that slug.
	 *
	 * @param string  $name      Name.
	 * @param string  $slug      Slug.
	 * @param int     $parent_id Parent term ID.
	 * @param Context $ctx       Context.
	 * @param int     $made      Counter.
	 * @return int Term ID, 0 on failure.
	 */
	private static function term( string $name, string $slug, int $parent_id, Context $ctx, int &$made ): int {
		$batch    = $ctx->batch;
		$existing = get_term_by( 'slug', $slug, 'product_cat' );
		if ( $existing instanceof \WP_Term ) {
			$id     = (int) $existing->term_id;
			$marker = (string) get_term_meta( $id, Marker::META, true );
			if ( '' !== $marker && $batch !== $marker ) {
				return 0;
			}
			// The slug carries the batch's secret token: ours, from a step that died part-way.
			if ( ! Marker::verified( 'term', $id, $batch ) ) {
				update_term_meta( $id, Marker::META, $batch );
				Marker::sign( 'term', $id, $batch );
			}
			return $id;
		}
		self::$batch = $batch;
		add_action( 'created_term', array( __CLASS__, 'mark' ), 1, 3 );
		try {
			$args   = array(
				'slug'   => $slug,
				'parent' => $parent_id,
			);
			$result = wp_insert_term( $name, 'product_cat', $args );
			if ( is_wp_error( $result ) && 'term_exists' === $result->get_error_code() ) {
				// Same name at this level (another batch with the same label): add the batch's token.
				$result = wp_insert_term( $name . ' (' . Marker::public_token( $batch ) . ')', 'product_cat', $args );
			}
		} finally {
			remove_action( 'created_term', array( __CLASS__, 'mark' ), 1 );
			self::$batch = '';
		}
		if ( is_wp_error( $result ) ) {
			return 0;
		}
		$id = (int) $result['term_id'];
		Marker::sign( 'term', $id, $batch );
		++$made;

		$ctx->created( 'term', $id );
		return $id;
	}
}