module ORDERS_NEW (DATAP, CHANNELS, STOCKS, INVOICE) is

!update "2021-b"  -- use standard operator priority

-------------------------------------------------------------------------------

process Order_p [Request: RequestChan, Cancel: CancelChan, Invoice: InvoiceChan, 
                 Withdraw: WithdrawChan] (M_p:Product, M_a:Amount, ref:Reference,
                 in var prd:Product, in var amt:Amount,in var sta:Status) is
   loop
      if sta == None then
         Request (ref, ?prd, ?amt) where
            prd <= M_p and amt <= M_a and amt > 0 of Amount;
         sta := Pending
      elsif sta == Pending then
         alt
            Cancel (ref);
            amt := 0 of Amount;
            sta := None
         []
            Withdraw (prd, amt) where amt > 0 of Amount;
            Invoice (ref);
            sta := Invoiced
         end alt
      end if
   end loop
end process

-------------------------------------------------------------------------------

-- Order process for ref=0, M_p=0

process Order_p0_r0 [Request: RequestChan, Cancel: CancelChan, Invoice:
                     InvoiceChan, Withdraw: WithdrawChan] (M_a: Amount) is
   Order_p [Request, Cancel, Invoice, Withdraw] (0 of Product, M_a,
            0 of Reference, 0 of Product, 0 of Amount, None)
end process

-------------------------------------------------------------------------------

-- Order process for ref=1, M_p=0

process Order_p0_r1 [Request: RequestChan, Cancel: CancelChan, Invoice:
                     InvoiceChan, Withdraw: WithdrawChan] (M_a: Amount) is
   Order_p [Request, Cancel, Invoice, Withdraw] (0 of Product, M_a,
            1 of Reference, 0 of Product, 0 of Amount, None)
end process

-------------------------------------------------------------------------------

-- Order process for ref=2, M_p=0

process Order_p0_r2 [Request: RequestChan, Cancel: CancelChan, Invoice:
                     InvoiceChan, Withdraw: WithdrawChan] (M_a: Amount) is
   Order_p [Request, Cancel, Invoice, Withdraw] (0 of Product, M_a,
            2 of Reference, 0 of Product, 0 of Amount, None)
end process

-------------------------------------------------------------------------------

--- Order process for ref=0, M_p=1

process Order_p1_r0 [Request: RequestChan, Cancel: CancelChan, Invoice:
                     InvoiceChan, Withdraw: WithdrawChan] (M_a: Amount) is
   Order_p [Request, Cancel, Invoice, Withdraw] (1 of Product, M_a,
            0 of Reference, 0 of Product, 0 of Amount, None)
end process

-------------------------------------------------------------------------------

--  Order process for ref=1, M_p=1

process Order_p1_r1 [Request: RequestChan, Cancel: CancelChan, Invoice:
                     InvoiceChan, Withdraw: WithdrawChan] (M_a: Amount) is
   Order_p [Request, Cancel, Invoice, Withdraw] (1 of Product, M_a,
            1 of Reference, 0 of Product, 0 of Amount, None)
end process

-------------------------------------------------------------------------------

-- Order process for ref=2, M_p=1

process Order_p1_r2 [Request: RequestChan, Cancel: CancelChan, Invoice:
                     InvoiceChan, Withdraw: WithdrawChan] (M_a: Amount) is
   Order_p [Request, Cancel, Invoice, Withdraw] (1 of Product, M_a,
            2 of Reference, 0 of Product, 0 of Amount, None)
end process

-------------------------------------------------------------------------------

end module