<?php

abstract class Boisson
{
	/**
	 * @var float
	 */
	protected $valeur;
	/**
	 * @var string
	 */
	protected $description;

	public function __construct()
	{
	}

	public function __toString()
	{
		return $this->getDescription() . ' (' . $this->getValeur() . ' &euro;)';
	}

	/**
	 * @return mixed
	 */
	public function getDescription()
	{
		return $this->description;
	}

	/**
	 * @param mixed $description
	 */
	public function setDescription($description)
	{
		$this->description = $description;
	}

	/**
	 * @return float
	 */
	public function getValeur()
	{
		return $this->valeur;
	}

	/**
	 * @param float $valeur
	 */
	public function setValeur($valeur)
	{
		$this->valeur = $valeur;
	}

	/**
	 * @param string $supplement
	 * @return Boisson
	 */
	public function ajoutSupplement($supplement)
	{
		return new $supplement($this);
	}

}

class Soda extends Boisson
{

	public function __construct()
	{
		parent::__construct();
		$this->description = 'Soda';
		$this->valeur = 4.0;
	}


}

abstract class SupplementDecorateur extends Boisson
{

	/**
	 * @var Boisson
	 */
	protected $boisson;

	public function __construct(Boisson $boisson)
	{
		$this->boisson = $boisson;
	}

}

class SupplementMenthe extends SupplementDecorateur
{

	public function getDescription()
	{
		return $this->boisson->getDescription() . ' + Menthe';
	}


	public function getValeur()
	{
		return $this->boisson->getValeur() + .20;
	}

}

class SupplementCitron extends SupplementDecorateur
{

	public function getDescription()
	{
		return $this->boisson->getDescription() . ' + Citron';
	}


	public function getValeur()
	{
		return $this->boisson->getValeur() + .05;
	}

}

class SupplementXL extends SupplementDecorateur
{

	public function getDescription()
	{
		return $this->boisson->getDescription() . ' + XL';
	}


	public function getValeur()
	{
		return $this->boisson->getValeur() * 1.30;
	}

}


$boisson = (new Soda())
	->ajoutSupplement(SupplementMenthe::class)
	->ajoutSupplement(SupplementCitron::class)
	->ajoutSupplement(SupplementCitron::class)
	->ajoutSupplement(SupplementXL::class);

print ($boisson);