namespace cart;

/**
 * 购物车
 * Class Cart
 */
class Cart
{
	/**
	 * 购物车标识
	 *
	 * @var string
	 */
	protected $cartName = 'cart';

	/**
	 * 商品资料
	 *
	 * @var
	 */
	protected $goods;

	public function __construct()
	{
		//$data = Session::get($this->cartName);
		$data = session($this->cartName);
		$this->setGoods(
			is_array($data) && isset($data['goods']) ? $data['goods'] : []
		);
	}

	/**
	 * 获得商品数据
	 *
	 * @return mixed
	 */
	public function getGoods()
	{
		return $this->goods;
	}

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

	/**
	 * 添加购物车
	 *
	 * @access  public
	 *
	 * @param array $data
	 *      $data为数组包含以下几个值
	 *      $Data= [
	 *      "id"=>1,                        //商品ID
	 *      "name"=>"后盾网2周年西服",         //商品名称
	 *      "num"=>2,                       //商品数量
	 *      "price"=>188.88,                //商品价格
	 *      "options"=>array(               //其他参数，如价格、颜色可以是数组或字符串|可以不添加
	 *      "color"=>"red",
	 *      "size"=>"L"
	 *      ]
	 *
	 * @throws \Exception
	 * @return void
	 */
	public function add($data)
	{
		if (!is_array($data) || !isset($data['id']) || !isset($data['name'])
			|| !isset($data['num'])
			|| !isset($data['price'])
		) {
			throw new \Exception('购物车ADD方法参数设置错误');
		}
		//添加商品支持多商品添加
		$options = isset($data['options']) ? $data['options'] : '';
		$sid = md5($data['id'] . serialize($options));
		//生成维一ID用于处理相同商品有不同属性时
		if (isset($this->goods[$sid])) {
			//如果数量为0删除商品
			if ($data['num'] == 0) {
				unset($this->goods[$sid]);
			} else {
				//已经存在相同商品时增加商品数量
				$this->goods[$sid]['num'] = $this->goods[$sid]['num']
					+ $data['num'];
				$this->goods[$sid]['total'] = $this->goods[$sid]['num']
					* $this->goods[$sid]['price'];
			}
		} else {
			if ($data['num'] != 0) {
				$this->goods[$sid] = $data;
				$this->goods[$sid]['total'] = $data['num'] * $data['price'];
			}
		}

		return $this->store();
	}

	/**
	 * 保存到SESSION
	 *
	 * @return mixed
	 */
	private function store()
	{
		$cart = [
			'goods' => $this->goods,
			'total_rows' => $this->getTotalNums(),
			'total_price' => $this->getTotalPrice(),
		];

		//return Session::set($this->cartName, $cart);
		return session($this->cartName, $cart);
	}

	/**
	 * 更新购物车数量
	 *
	 * @param $data
	 *  $data=[
	 *  "sid"=>'',//商品的唯一SID，不是商品的ID
	 *  "num"=>2,//商品数量
	 *  ]
	 *
	 * @return bool
	 * @throws \Exception
	 */
	public function update($data)
	{
		if (!isset($data['sid']) || !isset($data['num'])) {
			throw new \Exception('购物车update方法参数错误，缺少sid或num值');
		}
		$sid = $data['sid'];
		if (isset($this->goods[$sid])) {
			if ($data['num'] == 0) {
				unset($this->goods[$sid]);
			} else {
				$this->goods[$sid]['num'] = $data['num'];
				//进行修改
				$this->goods[$sid]['total'] = $this->goods[$sid]['num'] * $this->goods[$sid]['price'];
			}

			return $this->store();
		}

		return false;
	}

	/**
	 * 统计购物车中商品数量
	 */
	public function getTotalNums()
	{
		$rows = 0;
		foreach ($this->goods as $v) {
			$rows += $v['num'];
		}

		return $rows;
	}

	/**
	 * 获得商品汇总价格
	 */
	public function getTotalPrice()
	{
		$total = 0;
		foreach ($this->goods as $v) {
			$total += $v['price'] * $v['num'];
		}

		return $total;
	}

	/**
	 * 删除购物车
	 *
	 * @param $sid 商品SID编号
	 *
	 * @return bool
	 * @throws \Exception
	 */
	public function del($sid)
	{
		if (isset($this->goods[$sid])) {
			unset($this->goods[$sid]);
			$this->store();

			return true;
		}

		return false;
	}


	/**
	 * 删除所有商品
	 *
	 * @return bool
	 */
	public function flush()
	{
		$this->setGoods([]);
		$this->store();

		return true;
	}

	/**
	 * 获得购物车中的所有数据
	 * 包括商品数据、总数量、总价格
	 *
	 * @return mixed
	 */
	public function getAllData()
	{
		//return Session::get($this->cartName);
		return session($this->cartName);
	}

	/**
	 * 获得定单号
	 *
	 * @return string
	 */
	public function getOrderId()
	{
		return date('Ymd') . date('md') . substr(time(), -5) . substr(
				microtime(),
				2,
				5
			) . str_pad(mt_rand(1, 99), 2, '0', STR_PAD_LEFT);
	}
}