Herança e Polimorfismo

#PHP
#MySQL
#POO

Na quarta parte do meu projeto de sistema de gestão de academias de artes marciais, vou expandir os conceitos de herança e polimorfismo na linguagem PHP.

<?php
include_once "connection.php";

class User
{
  private $connection;
  private string $name;
  private string $description;
  private string $pathImage;
  private string $phone;
  private string $email;
  private string $level;
  private string $status;
  private string $password;
  private int $days;
  private string $addressline1;
  private string $addressline2;
  private string $neighborhood;
  private string $city;
  private string $state;
  private string $country;
  private string $postal_code;
  private string $updatedDate;
  private string $createdDate;

  public function __construct($name, $description, $phone, $email, $level, $status, $days, $addressline1, $addressline2, $neighborhood, $city, $state, $country, $postal_code, $updatedDate, $pathImage = "", $hashedPassword = "", $createdDate = "")
  {
      $dbConnection = new Connection();
      $this->connection = $dbConnection->connect();

      $this->name = $name;
      $this->description = $description;
      $this->pathImage = $pathImage;
      $this->phone = $phone;
      $this->email = $email;
      $this->level = $level;
      $this->status = $status;
      $this->password = $hashedPassword;
      $this->days = $days;
      $this->addressline1 = $addressline1;
      $this->addressline2 = $addressline2;
      $this->neighborhood = $neighborhood;
      $this->city = $city;
      $this->state = $state;
      $this->country = $country;
      $this->postal_code = $postal_code;
      $this->updatedDate = $updatedDate;
      $this->createdDate = $createdDate;
  }

  public function create_user()
  {
      try {
          $insert = $this->connection->prepare("INSERT INTO users (name, description, pathImage, phone, email, level, status, password, days, addressline1, addressline2, neighborhood, city, state, country, postal_code, updatedDate, createdDate) VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?)");

          echo "</br> INSERT INTO users (name, description, pathImage, phone, email, level, status, password, days, addressline1, addressline2, neighborhood, city, state, country, postal_code, updatedDate, createdDate) VALUES ('$this->name', '$this->description', '$this->pathImage', '$this->phone', '$this->email', '$this->level', '$this->status', '$this->password', '$this->days', '$this->addressline1', '$this->addressline2', '$this->neighborhood', '$this->city', '$this->state', '$this->country', '$this->postal_code', '$this->updatedDate', '$this->createdDate')";

          $insert->bind_param("ssssssssdsssssssss", $this->name, $this->description, $this->pathImage, $this->phone, $this->email, $this->level, $this->status, $this->password, $this->days, $this->addressline1, $this->addressline2, $this->neighborhood, $this->city, $this->state, $this->country, $this->postal_code, $this->updatedDate, $this->createdDate);
          $result = $insert->execute();
          $insert->close();

          if (!$result) {
              throw new Exception("Error to create a user.");
          }

          return true;
      } catch (Exception $e) {
          error_log("Error creating user: " . $e->getMessage());
          return false;
      }
  }

  public function update_user_by_id(int $user_id): bool
  {
      try {
          $update = $this->connection->prepare("UPDATE users SET name = ?, description = ?, phone = ?, email = ?, level = ?, status = ?, days = ?, addressline1 = ?, addressline2 = ?, neighborhood = ?, city = ?, state = ?, country = ?, postal_code = ?, updatedDate = ? WHERE user_id = ?");

          $update->bind_param("ssssdsssssssssi", $this->name, $this->description, $this->phone, $this->email, $this->level, $this->status, $this->days, $this->addressline1, $this->addressline2, $this->neighborhood, $this->city, $this->country, $this->postal_code, $this->updatedDate, $user_id);
          $result = $update->execute();
          $update->close();

          if (!$result) {
              throw new Exception("Error to update a user.");
          }

          return true;
      } catch (Exception $e) {
          error_log("Error updating user: " . $e->getMessage());
          return false;
      }
  }

  public static function update_user_password_by_id($user_id, $password, $updatedDate): bool
  {
      $dbConnection = new Connection();
      $connection = $dbConnection->connect();

      $update = $connection->prepare("UPDATE users SET password = ?, updatedDate = ? WHERE user_id = ?");
      $update->bind_param("ssi", $password, $updatedDate, $user_id);
      $result = $update->execute();
      $update->close();

      return $result;
  }

  public static function update_user_password_by_email($email, $password, $updatedDate): bool
  {
      $dbConnection = new Connection();
      $connection = $dbConnection->connect();

      $update = $connection->prepare("UPDATE users SET password = ?, updatedDate = ? WHERE email = ?");
      $update->bind_param("ssi", $password, $updatedDate, $email);
      $result = $update->execute();
      $update->close();

      return $result;
  }

  public function delete_user_by_id(int $user_id): bool
  {
      $delete = $this->connection->prepare("DELETE FROM users WHERE user_id = ?");
      $delete->bind_param("i", $user_id);
      $result = $delete->execute();
      $delete->close();

      return $result;
  }

  public static function find_user($query)
  {
      try {
          $dbConnection = new Connection();
          $connection = $dbConnection->connect();

          if (is_numeric($query)) {
              $stmt = $connection->prepare("SELECT * FROM users WHERE user_id = ?");
              $stmt->bind_param("i", $query);
          } else {
              $stmt = $connection->prepare("SELECT * FROM users WHERE email = ? OR name = ?");
              $stmt->bind_param("ss", $query, $query);
          }

          $stmt->execute();
          $result = $stmt->get_result();
          $stmt->close();

          if ($result->num_rows > 0) {
              $user_data = $result->fetch_assoc();
              return $user_data;
          } else {
              return null;
          }
      } catch (Exception $e) {
          error_log("Error finding user: " . $e->getMessage());
          return null;
      }
  }

  public static function login_user($email, $password)
  {
      try {
          $dbConnection = new Connection();
          $connection = $dbConnection->connect();

          $query = "SELECT * FROM users WHERE email = ?";
          $stmt = $connection->prepare($query);
          $stmt->bind_param("s", $email);
          $stmt->execute();
          $result = $stmt->get_result();

          if ($result->num_rows === 1) {
              $user = $result->fetch_assoc();

              if (password_verify($password, $user["password"])) {
                  return $user;
              } else {
                  return false;
              }
          } else {
              return false;
          }

          $stmt->close();
          $connection->close();
      } catch (Exception $e) {
          error_log("Error during login: " . $e->getMessage());
          return false;
      }
  }
}

Herança é um dos pilares fundamentais da programação orientada a objetos (POO). Ela permite que você crie uma nova classe (conhecida como subclasse ou classe filha) com base em uma classe existente (superclasse ou classe pai). A subclasse herda os atributos e métodos da superclasse, o que promove a reutilização de código e a criação de uma hierarquia de classes. No exemplo que apresentarei, a classe SubUser herda da classe User, o que significa que SubUser possui todos os atributos e métodos de User, além da capacidade de adicionar ou substituir seus próprios.

<?php
include_once "connection.php";
include_once "user.php";

class SubUser extends User
{
  private $connection;
  private string $type;

  public function __construct($name, $description, $phone, $email, $type, $status, $days, $addressline1, $addressline2, $neighborhood, $city, $state, $country, $postal_code, $updatedDate, $pathImage = "", $hashedPassword = "", $createdDate = "")
  {
      $dbConnection = new Connection();
      $this->connection = $dbConnection->connect();
      
      parent::__construct($name, $description, $phone, $email, $type, $status, $days, $addressline1, $addressline2, $neighborhood, $city, $state, $country, $postal_code, $updatedDate, $pathImage, $hashedPassword, $createdDate);
      $this->type = $type;
  }

  public function create_user()
  {
      try {
          $insert = $this->connection->prepare("INSERT INTO users (name, description, pathImage, phone, email, type, status, password, days, addressline1, addressline2, neighborhood, city, state, country, postal_code, updatedDate, createdDate) VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?)");

          $insert->bind_param("ssssssssdsssssssss", $this->name, $this->description, $this->pathImage, $this->phone, $this->email, $this->type, $this->status, $this->password, $this->days, $this->addressline1, $this->addressline2, $this->neighborhood, $this->city, $this->state, $this->country, $this->postal_code, $this->updatedDate, $this->createdDate);
          $result = $insert->execute();
          $insert->close();

          if (!$result) {
              throw new Exception("Error to create a user.");
          }

          return true;
      } catch (Exception $e) {
          error_log("Error creating user: " . $e->getMessage());
          return false;
      }
  }

  public function update_user_by_id(int $user_id): bool
  {
      try {
          $update = $this->connection->prepare("UPDATE users SET name = ?, description = ?, phone = ?, email = ?, type = ?, status = ?, days = ?, addressline1 = ?, addressline2 = ?, neighborhood = ?, city = ?, state = ?, country = ?, postal_code = ?, updatedDate = ? WHERE user_id = ?");

          $update->bind_param("ssssdsssssssssi", $this->name, $this->description, $this->phone, $this->email, $this->type, $this->status, $this->days, $this->addressline1, $this->addressline2, $this->neighborhood, $this->city, $this->country, $this->postal_code, $this->updatedDate, $user_id);
          $result = $update->execute();
          $update->close();

          if (!$result) {
              throw new Exception("Error to update a user.");
          }

          return true;
      } catch (Exception $e) {
          error_log("Error updating user: " . $e->getMessage());
          return false;
      }
  }

  public static function update_user_password_by_id($user_id, $password, $updatedDate): bool
  {
      $result = parent::update_user_password_by_id($user_id, $password, $updatedDate);
      return $result;

      return $result;
  }

  public static function update_user_password_by_email($email, $password, $updatedDate): bool
  {

      $result = parent::update_user_password_by_email($email, $password, $updatedDate);
      return $result;

      return $result;
  }

  public function delete_user_by_id($user_id): bool
  {
      $result = parent::delete_user_by_id($user_id);

      return $result;
  }

  public static function find_user($query)
  {
      $result = parent::find_user($query);
      return $result;
  }

  public static function login_user($email, $password)
  {
      $result = parent::login_user($email, $password);
      return $result;
  }
}

Polimorfismo é outro conceito crucial da POO que permite que objetos de classes diferentes sejam tratados de maneira uniforme. Isso significa que você pode usar um método com o mesmo nome, mas com diferentes implementações, em várias classes. Em PHP, isso é frequentemente alcançado usando interfaces ou métodos abstratos nas superclasses. O polimorfismo permite que você escreva código mais genérico e flexível, tornando-o valioso em situações em que diferentes classes precisam se comportar de maneira semelhante.

Classe Base (User): A classe User atua como uma classe base com atributos e métodos comuns para todos os tipos de usuários. Ela possui um construtor que inicializa todos os atributos e métodos para criar, atualizar e buscar usuários no banco de dados. A classe também lida com a autenticação de login.
Classe Filha (SubUser): A classe SubUser herda da classe User e adiciona um novo atributo chamado type. Ela também redefine os métodos create_user, update_user_by_id, update_user_password_by_id, update_user_password_by_email, delete_user_by_id, find_user, e login_user. O uso do parent:: chama os métodos correspondentes da classe base quando necessário, permitindo a extensão sem duplicação de código.
Reescrita de Métodos: Os métodos na classe SubUser são reescritos para acomodar o novo atributo type. Por exemplo, o método create_user inclui o tipo de usuário ao inserir no banco de dados. Aqui, o conceito de polimorfismo está sendo aplicado, pois a mesma assinatura de método (create_user) está sendo usada de forma diferente na classe filha.

contate me clicando aqui

link do repositório