invoiceninja/app/Repositories/ClientContactRepository.php

<?php

namespace App\Repositories;

use App\Models\Client;
use App\Models\ClientContact;

/**
 * ClientContactRepository
 */
class ClientContactRepository extends BaseRepository
{

	public function save($contacts, Client $client) : void
	{

		/* Convert array to collection */
		$contacts = collect($contacts);

		/* Get array of IDs which have been removed from the contacts array and soft delete each contact */
		collect($client->contacts->pluck('id'))->diff($contacts->pluck('id'))->each(function($contact){

			ClientContact::destroy($contact);

		});

		/* Set first record to primary - always*/
		$contacts = $contacts->sortBy('is_primary');

		$contacts->first(function($contact){

			$contact['is_primary'] = true;
			$contact->save();

		});

		//loop and update/create contacts
		$contacts->each(function ($contact) use ($client){ 

			$update_contact = ClientContact::firstOrNew(
				['id' => $contact['id']],
				[
					'client_id' => $client->id, 
					'company_id' => $client->company_id,
					'user_id' => auth()->user()->id
				]
			);

			$update_contact->fill($contact);

			$update_contact->save();
		});


	}

}