package Interfaces;

import Apresentacao.DataAccessDTO;
import Dominio.Entity;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;

public abstract class Repository<T extends Entity> {

    private static Connection conn;
    private final String DRIVER = "com.mysql.jdbc.Driver";
    private String host;
    protected String sql;
    private String MySQL = "jdbc:mysql://";
    private boolean connected = false;

    private boolean connect() throws SQLException {
        return this.connect(DataAccessDTO.host, DataAccessDTO.user, DataAccessDTO.password, DataAccessDTO.database);
    }

    private boolean connect(String host, String user, String password, String dbName) throws SQLException {
        this.host = host;
        try {
            Class.forName(DRIVER);
            String dbMySQL = MySQL + host + "/" + dbName;
            conn = DriverManager.getConnection(dbMySQL, user, password);
            conn.setAutoCommit(false);
            this.connected = true;
        } catch (ClassNotFoundException ex) {
            System.out.println("Driver JDBC Não encontrado");
        }
        return this.connected;
    }

    private void disconnect() {
        try {
            Class.forName(DRIVER);
            conn = null;
            this.connected = false;
        } catch (ClassNotFoundException ex) {
            System.out.println("Driver JDBC Não encontrado");
        }
    }

    protected ResultSet executeQuery(String sql) throws SQLException {
        if (this.connect()) {
            Statement statement = conn.createStatement();
            ResultSet result = statement.executeQuery(sql);
            this.disconnect();
            return result;
        }
        return null;
    }

    public void insert(T obj) throws SQLException {
        this.persistInsert(obj);
        ResultSet res = this.executeQuery(this.sql);
        obj.setId(res.getInt("id"));
    }

    public void update(T obj) throws SQLException, Exception {
        if (obj.getId() == 0) {
            throw new Exception("Não é possivel atualizar o registro sem um 'ID' na Entidade.");
        }
        this.persistUpdate(obj);
        this.executeQuery(this.sql);
    }

    public void delete(T obj) throws SQLException {
        this.persistDelete(obj);
        this.executeQuery(this.sql);
    }

    protected abstract void persistInsert(T obj);

    protected abstract void persistDelete(T obj);

    protected abstract void persistUpdate(T obj);
}