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<?php // only copy this line if needed

add_filter( 'wc_customer_order_csv_export_order_headers',              'wc_product_vendors_csv_export_integration_add_column_headers' );
add_filter( 'wc_customer_order_csv_export_order_line_item',            'wc_product_vendors_csv_export_integration_modify_line_item', 10, 5 );
add_filter( 'wc_customer_order_csv_export_order_row_one_row_per_item', 'wc_product_vendors_csv_export_integration_add_row_data', 10, 4 );

function wc_product_vendors_csv_export_integration_add_column_headers( $headers ) {

	$headers['vendor'] = 'Vendor';

	return $headers;
}

function wc_product_vendors_csv_export_integration_modify_line_item( $line_item, $item, $product, $order, $csv_generator ) {

	// bail out as we only need this data if it's one row per item
	if ( ! wc_product_vendors_csv_export_integration_is_one_row_per_item( $csv_generator ) ) {
		return $order_data;
	}

	if ( $product instanceof WC_Product && 'product' === get_post_type( $product->id ) ) {

		// add product id to line_item
		$line_item['product_vendors_product_id'] = $product->id;
	}

	return $line_item;
}

function wc_product_vendors_csv_export_integration_add_row_data( $order_data, $item, $order, $csv_generator ) {
	
	// bail out as this only works with one row per item
	if ( ! wc_product_vendors_csv_export_integration_is_one_row_per_item( $csv_generator ) ) {
		return $order_data;
	}

	if ( ! empty( $item['product_vendors_product_id'] ) ) {
		$vendor = WC_Product_Vendors_Utils::is_vendor_product( $item['product_vendors_product_id'] );

		if ( ! empty( $vendor[0] ) ) {
			$vendor_data = WC_Product_Vendors_Utils::get_vendor_data_by_id( $vendor[0]->term_id );

			if ( ! empty( $vendor_data ) ) {
				$order_data['vendor'] = $vendor_data['name'];
			}
		}
	}

	return $order_data;
}


function wc_product_vendors_csv_export_integration_is_one_row_per_item( $csv_generator ) {

	// sanity check - bail if CSV Export is not active, or if the provided paramater is not as expected
	if ( ! function_exists( 'wc_customer_order_csv_export' ) || ! $csv_generator instanceof WC_Customer_Order_CSV_Export_Generator ) {
		return false;
	}

	$one_row_per_item = false;

	// determine if the selected format is "one row per item"
	if ( version_compare( wc_customer_order_csv_export()->get_version(), '4.0.0', '<' ) ) {

		$one_row_per_item = ( 'default_one_row_per_item' === $csv_generator->order_format || 'legacy_one_row_per_item' === $csv_generator->order_format );

	// v4.0.0 - 4.0.2
	} elseif ( ! isset( $csv_generator->format_definition ) ) {

		// get the CSV Export format definition
		$format_definition = wc_customer_order_csv_export()->get_formats_instance()->get_format( $csv_generator->export_type, $csv_generator->export_format );

		$one_row_per_item = isset( $format_definition['row_type'] ) && 'item' === $format_definition['row_type'];

	// v4.0.3+
	} else {

		$one_row_per_item = 'item' === $csv_generator->format_definition['row_type'];
	}

	return $one_row_per_item;
}