contact-cards.js

handleSave = async () => {
    if (!this.state.editing.id) {
      const newId = Math.max(...this.state.contacts.map(contact => contact.id)) + 1;
      let editing = { ...this.state.editing };
      editing.id = newId;
      await this.setState({ editing });
    }
    const idToUpdate = this.state.editing.id;
    const duplicate = [...this.state.contacts].filter(contact => contact.id !== idToUpdate);
    this.setState({ contacts: [...duplicate, this.state.editing] }, () => this.toggleModal());
  };