module Trade
  module PaymentType::Paypal

    def paypal_prepay
      paypal_payment = PayPal::SDK::REST::DataTypes::Payment.new(paypal_params)

      result = paypal_payment.create
      if result
        self.update(payment_id: paypal_payment.id)
      else
        self.errors.add :payment_id, paypal_payment.error.inspect
      end
      paypal_payment.links.find{ |v| v.rel == 'approval_url' }.href
    end

    def paypal_execute(params)
      return unless self.payment_id
      paypal_payment = PayPal::SDK::REST::DataTypes::Payment.find(self.payment_id)
      paypal_payment.execute(payer_id: params[:PayerID])

      paypal_record(paypal_payment)
    end

    def paypal_result
      return self if self.payment_status == 'all_paid'

      return unless self.payment_id
      paypal_payment ||= PayPal::SDK::REST::DataTypes::Payment.find(self.payment_id)
      trans = paypal_payment.transactions[0]

      if paypal_payment.state == 'approved'
        self.change_to_paid! type: 'PaypalPayment', payment_uuid: trans.related_resources[0].sale.id, params: trans
      else
        errors.add :base, paypal_payment.error.inspect
      end
    end

    def paypal_params
      {
        intent: 'sale',
        payer: {
          payment_method: 'paypal'
        },
        redirect_urls: {
          return_url: url_helpers.paypal_execute_my_order_url(self.id),
          cancel_url: url_helpers.cancel_my_order_url(self.id)
        },
        transactions: {
          item_list: {
            items: paypal_items_params
          },
          amount: {
            total: self.unreceived_amount,
            currency: self.currency.upcase
          },
          description: ''
        }
      }
    end

    def paypal_items_params
      items = order_items.map do |item|
        {
          name: item.good.name,
          sku: item.good.sku,
          price: item.good.price.to_money.exchange_to(self.currency).to_s,
          currency: self.currency.upcase,
          quantity: item.number
        }
      end
      serves = order_serves.map do |item|
        {
          name: item.serve.name,
          sku: item.serve.id,
          price: item.price.to_money.exchange_to(self.currency).to_s,
          currency: self.currency.upcase,
          quantity: 1
        }
      end
      items + serves
    end

  end
end