7 erros de clean code

Author.js

import db from '@/db'

class Author {
  constructor(firstName, lastName) {
    this.firstName = firstName;
    this.lastName = lastName;
    this.fullName = firstName + ' ' + lastName
  }

  update(firstName, lastName) {
    this.firstName = firstName;
    this.lastName = lastName;
    this.fullName = firstName + ' ' + lastName

    this.save(this.firstName, this.lastName)
  }

  save(firstName, lastName) {
    db.saveAuthor(firstName, lastName)
  }

  getBooksByGenre(genre) {
    const books = []
    const allAuthorBooks = db.getAuthorBooks(this.firstName, this.lastName)

    allAuthorBooks.forEach(book => {
      const genreModel = db.getGenreById(book.genre_id)
      if (genreModel.name === genre) {
        books.push(book)
      }
    })

    return books
  }
}