<?php
abstract class BaseList{
	protected $lastid;
    protected $data;
    public function __construct(){
    	$this->lastid=0;
        $this->data=array();
    }
    public function update($params){
    	foreach ($this->data as $item){
        	if ($item->getId()==$params['id']){
            	$item->update($params);
                break;
            }
        }
    }
    public function display(){
    	foreach ($this->data as $item){
        	$item->displayInfo();
        }
    }
    public function delete($id){
    	for ($i=0;$i<count($this->data);$i++){
        	if ($this->data[$i]->getId()==$id){
            	array_splice($this->data, $i, 1);
                break;
            }
        }
    }
    public abstract function add($params);
}
class CategoryList extends BaseList{
    public function add($params){
    	$this->lastid++;
        $params['id']=$this->lastid;
        $category=new Category($params);
        array_push($this->data,$category);
	}  
}
class ParameterList extends BaseList{
    public function add($params){
    	$this->lastid++;
        $params['id']=$this->lastid;
        $category=new Parameter($params);
        array_push($this->data,$category);
	}  
}
class BackpackList extends BaseList{
    public function add($params){
    	$this->lastid++;
        $params['id']=$this->lastid;
        $category=new Backpack($params);
        array_push($this->data,$category);
	}  
}
class Category{
  private $id;
  private $name;
  public function __construct($params){
      $this->id=$params['id'];
      $this->name=$params['name'];
  }
  public function __delete(){}
  public function update($params){
      if (isset($params['name'])){
          $this->name=$params['name'];
      }
  }
  public function displayInfo(){
      echo $this->id.'. '.$this->name.'</br>';
  }
  public function getId(){
  	  return $this->id;
  }
}
class Parameter{
  private $id;
  private $name;
  private $unit;
  public function __construct($params){
      $this->id=$params['id'];
      $this->name=$params['name'];
      $this->unit=$params['unit'];
  }
  public function __delete(){}
  public function update($params){
      if (isset($params['name'])){
          $this->name=$params['name'];
      }
      if (isset($params['unit'])){
          $this->unit=$params['unit'];
      }
  }
  public function displayInfo(){
      echo $this->id.'. '.$this->name.' (<i>'.$this->unit.'</i>)</br>';
  }
  public function getId(){
  	  return $this->id;
  }
}

class Backpack{
  private $id;
  private $brand;
  private $model;
  private $price;
  private $category;
  private $parameters;
  public function __construct($params){
      $this->id=$params['id'];
      $this->brand=$params['brand'];
      $this->model=$params['model'];
      $this->price=$params['price'];
      $this->category=$params['category'];
      $this->parameters=$params['parameters'];
  }
  public function __delete(){}
  public function update($params){
      if (isset($params['brand'])){
          $this->brand=$params['brand'];
      }
      if (isset($params['model'])){
          $this->model=$params['model'];
      }
      if (isset($params['price'])){
          $this->price=$params['price'];
      }
      if (isset($params['category'])){
          $this->category=$params['category'];
      }
      if (isset($params['parameters'])){
          $this->parameters=$params['parameters'];
      }
  }
  public function displayInfo(){
      //echo $this->id.'. '.$this->name.' (<i>'.$this->unit.'</i>)</br>';
      echo '<b>'.$this->id.'. '.$this->brand.' '.$this->model.'</b>
      </br>Ціна: '.$this->price.' грн</br>Категорія: '.$this->category.'</br>
      Характеристики:</br>';
      $param_data=json_decode($this->parameters,true);
      foreach ($param_data as $item){
      	echo $item["name"].': '.$item["value"].'</br>';
      }
  }
  public function getId(){
  	  return $this->id;
  }
}

$data1=array('name'=>'Міські Рюкзаки');
$data2=array('name'=>'Трекінгові Рюкзаки');
$data3=array('id'=>'1','name'=>'Експедиційні Рюкзаки');
$catList=new CategoryList();
$catList->add($data1);
$catList->add($data2);
$catList->update($data3);
//$catList->add($data3);
//$catList->delete(2);
$catList->display();
//$data=array('id'=>1,'brand'=>'Osprey','model'=>'Flare','price'=>'3000','category'=>'Міські рюкзаки','parameters'=>'[{"name":"Вага","value":"1 кг"},{"name":"Об\'єм","value":"23 л"}]');
//$data2=array('id'=>2,'brand'=>'Fjord Nansen','model'=>'Bodo','price'=>'4000','category'=>'Туристичні рюкзаки','parameters'=>'[{"name":"Вага","value":"1.6 кг"},{"name":"Об\'єм","value":"40 л"}]');
//$a=new Backpack($data);
//$a->displayInfo();
//$a->update($data2);
//$a->displayInfo();
?>