Synchroniser le stock entre plusieurs produits WooCommerce

script.js

jQuery( document ).ready(function($){
	$sync = $('.sync-stock-select');
	$sync.select2({
		minimumInputLength:1,
		placeholder: 'Chercher un produit…',
		ajax: {
		  url: '/wp-json/wp/v2/product',
		  dataType: 'json',
		  method:'GET',
		  delay: 250,
		  data: function (params) {
			var query = {
			  search: params.term,
			}
			return query;
		  },
		  processResults: function (data) {
			var res = data.map(function(r) {
				return {
					id:r.id,
					text: `${r.title.rendered} (id:${r.id})`
				};
			});
			return {
			  results: res
			};
		  }
		}
	  });
});

sync-stock-acf.php

<?php

add_action( 'init', 'w_load_acf_fields', 9 );
function w_load_acf_fields() {
	if( function_exists('acf_add_local_field_group') ):
	acf_add_local_field_group(array(
		'key' => 'group_5fa29f12476fd',
		'title' => 'Synchronisation de stock',
		'fields' => array(
			array(
				'key' => 'field_5fa29f25937ba',
				'label' => 'Le stock de ce produit doit être synchronisé avec celui-ci',
				'name' => 'synchro_stock_with',
				'type' => 'post_object',
				'instructions' => '',
				'required' => 0,
				'conditional_logic' => 0,
				'wrapper' => array(
					'width' => '',
					'class' => '',
					'id' => '',
				),
				'acfe_permissions' => array(
					0 => 'administrator',
					1 => 'editor',
					2 => 'shop_manager',
				),
				'post_type' => array(
					0 => 'product',
				),
				'taxonomy' => '',
				'allow_null' => 1,
				'multiple' => 1,
				'return_format' => 'id',
				'save_custom' => 0,
				'save_post_status' => 'publish',
				'acfe_bidirectional' => array(
					'acfe_bidirectional_enabled' => '1',
					'acfe_bidirectional_related' => array(
						0 => 'field_5fa29f25937ba',
					),
				),
				'ui' => 1,
			),
		),
		'location' => array(
			array(
				array(
					'param' => 'post_type',
					'operator' => '==',
					'value' => 'product',
				),
			),
		),
		'menu_order' => 0,
		'position' => 'normal',
		'style' => 'default',
		'label_placement' => 'top',
		'instruction_placement' => 'label',
		'hide_on_screen' => '',
		'active' => true,
		'description' => '',
		'acfe_display_title' => '',
		'acfe_autosync' => '',
		'acfe_permissions' => '',
		'acfe_form' => 0,
		'acfe_meta' => '',
		'acfe_note' => '',
	));
	endif;
}

sync-stock-actions.php

<?php

add_action( 'woocommerce_product_set_stock', 'w_sync_stock' );
function w_sync_stock( $product ) {
	remove_action( 'woocommerce_product_set_stock', 'w_sync_stock' );
	$synced_products = get_post_meta( $product->get_id(), 'synchro_stock_with', true );
	foreach ( $synced_products as $synced_product ) {
		$other = wc_get_product( $synced_product );
		$other->set_stock_quantity( $product->get_stock_quantity() );
		$other->save();
	}
	add_action( 'woocommerce_product_set_stock', 'w_sync_stock' );
}

add_action('woocommerce_variation_set_stock', 'w_sync_variation_stock' );
function w_sync_variation_stock( $variation ) {
	remove_action( 'woocommerce_variation_set_stock', 'w_sync_variation_stock' );
	$parent = $variation->get_parent_id();
	$synced_products = get_post_meta( $parent, 'synchro_stock_with', true );
	foreach ( $synced_products as $synced_product ) {
		$atts = $variation->get_variation_attributes();
		$parent = wc_get_product( $synced_product );
		$synced_var = $parent->get_available_variations();
		$same = wp_list_filter( $synced_var, array( 'attributes' => $atts ) );
		if ( ! empty( $same ) ) {
			$target = reset( $same );
			$target = $target['variation_id'];
			$other = wc_get_product( $target );
			$other->set_stock_quantity( $variation->get_stock_quantity() );
			$other->save();
		}
	}
	add_action( 'woocommerce_variation_set_stock', 'w_sync_variation_stock' );
}

sync-stock-metabox.php

<?php

add_action( 'add_meta_boxes_product', 'register_sync_metabox' );
function register_sync_metabox() {
	add_meta_box( 'sync_metabox', 'Synchronisation du stock', 'sync_metabox', 'product', 'side', 'default');
}

add_action( 'admin_enqueue_scripts', 'my_admin_scripts_method' );
function my_admin_scripts_method() {
	wp_register_script( 'sync-script', plugins_url( 'script.js', __FILE__ ), 'selectwoo' );
}

function sync_metabox( $post ) {
	wp_nonce_field( 'update-synced_p_' . $post->ID, '_wpnonce_update_synced_p' );
	wp_enqueue_script( 'sync-script');
	?>
	<p>
		<label>Sélectionnez les produits avec lesquels vous souhaitez syncroniser le stock :</label><br>
		<input type="hidden" name="synchro_stock_with" value="" />
		<select name="synchro_stock_with[]" class="sync-stock-select" style="width:100%" multiple="multiple">
		<?php
	
		$products_synced = get_post_meta( $post->ID,'synchro_stock_with', true );
		if ( ! empty( $products_synced ) ) {
			foreach ( $products_synced as $id ) {
				$titre_produit = get_the_title( $id ) . " (id:{$id})";
				printf( '<option value="%1$s" selected>%2$s</option>', $id, $titre_produit );
			}
		}
		?>
		</select>
	</p>
	<?php
}

add_action('save_post','sauvegarde_metabox');
function sauvegarde_metabox( $post_id ){
	if ( ! wp_doing_ajax() && isset($_POST['synchro_stock_with'] ) ) {
    		check_admin_referer( 'update-synced_p_' . $post_id, '_wpnonce_update_synced_p' );

		$meta_key = 'synchro_stock_with';

		$previously_synced = (array) get_post_meta( $post_id, $meta_key, true );
		$freshly_synced = empty( $_POST['synchro_stock_with'] ) ? array() : array_map( 'intval', (array) $_POST['synchro_stock_with'] );

		update_post_meta( $post_id, $meta_key, $freshly_synced );

		foreach ( $freshly_synced as $id ) {
			$v = $freshly_synced;
			$v[] = $post_id;
			unset( $v[ array_search( $id, $v ) ] );
			update_post_meta( $id, $meta_key, $v );
		}

		$to_del = array_diff( $previously_synced, $freshly_synced );
		$erase_these = $to_del == $previously_synced;
		foreach ( $to_del as $id ) {
			if ( $erase_these ) {
				$s = (array) get_post_meta( $id, $meta_key, true );
				if ( false !== ( $key = array_search( intval( $post_id ), $s ) ) ) {
					unset( $s[ $key ] );
					update_post_meta( $id, $meta_key, $s );
				}
			} else {
				update_post_meta( $id, $meta_key, array() );
			}
		}
	}
}