adding some basic exchange

econ/business.py

@@ -1,5 +1,5 @@
 class Business():
-    def __init__(self,production,balance) -> None:
+    def __init__(self,id,production,balance) -> None:
         """production (dict): {
                                 name: 'Gem',
                                 amount: 4,
@@ -10,6 +10,7 @@ class Business():
                             }
         balance (int): Starting Balance 
         """
+        self.id=id
         self.production=production
         self.balance=balance
         #Setup Inventory

econ/exchange.py

@@ -0,0 +1,172 @@
+_bal="balance"
+from lightmatchingengine.lightmatchingengine import LightMatchingEngine,Side,Trade,Order
+class Exchange():
+    """
+    Basic Commodity exchange.
+    """
+    
+    def __init__(self) -> None:
+        
+        self.account={}
+        self.escrow={}
+        self.lme=LightMatchingEngine()
+        self.order_account_map={}
+        self.orders={}
+        self.executed_trades=[]
+        self.order_total_price={}
+        self.market_rate={}
+        self.best_ask={}
+        self.best_bid={}
+        pass
+
+    def add_to_account(self,account_id,resource,amount):
+        """
+        Adds resources to account escrow
+        """
+        #check if account exists
+        if account_id not in self.account:
+            self.account[account_id]={_bal: 0}
+        #check if ressource exists
+        if resource not in self.account[account_id]:
+            self.account[account_id][resource]=0
+        
+        self.account[account_id][resource]+=amount
+    
+    def remove_from_account(self,account_id,resource,amount) -> int:
+        """
+        Remove resources from account. Returns amount retrieved
+        """
+        #check if account exists
+        if account_id not in self.account:
+            self.account[account_id]={_bal: 0}
+        #check if ressource exists
+        if resource not in self.account[account_id]:
+            self.account[account_id][resource]=0
+        ret=amount
+        remain=self.account[account_id][resource]-amount
+        if remain<0:
+            ret=self.account[account_id][resource]
+            self.account[account_id][resource]=0
+        else:
+            self.account[account_id][resource]-=amount
+        return ret
+
+    def _move_to_escrow(self,account_id,resource,amount):
+        """
+        Adds resources from account to escrow. Return true if done.
+        """
+        if not self.check_account_resource(account_id,resource,amount):
+            return False
+        
+        #check if account exists
+        if account_id not in self.escrow:
+            self.escrow[account_id]={_bal: 0}
+        #check if ressource exists
+        if resource not in self.escrow[account_id]:
+            self.escrow[account_id][resource]=0
+        
+        self.escrow[account_id][resource]+=amount
+        self.account[account_id][resource]-=amount
+        return True
+    
+    def _move_to_account(self,account_id,resource,amount):
+        """
+        Move resources from escrow to account.
+        """
+        ret=amount
+        self.escrow[account_id][resource]-=amount
+        
+       
+        if resource not in self.account[account_id]:
+            self.account[account_id][resource]=0
+        self.account[account_id][resource]+=amount
+
+
+    def check_account_resource(self,account_id,resource,amount):
+        """
+        Checks if account has sufficient resources in inventory
+        """
+        if account_id not in self.account:
+            self.account[account_id]={_bal: 0}
+        #check if ressource exists
+        if resource not in self.account[account_id]:
+            self.account[account_id][resource]=0
+        
+        if self.account[account_id][resource]>=amount:
+            return True
+        return False
+
+    def submit_order(self,account_id,resource,amount,price,side :int) -> Order:
+        """
+        Submits an order to the exchange if resources are sufficent.
+        Price is price per single item.
+        Returns an order if the order is active. Returns None if submit has failed.
+        """
+        # calculate price for complete order fullfilment
+        full_price=price*amount
+
+
+        # Move resources into escrow
+        if side==Side.BUY:
+            escrow=self._move_to_escrow(account_id,_bal,full_price)
+        else:
+            escrow=self._move_to_escrow(account_id,resource,amount)
+        
+        if not escrow:
+            # no sufficient resources
+            return None
+        # create order and execude any trades
+        order,trades=self.lme.add_order(resource,price,amount,side) 
+        self.orders[order.order_id]=order
+        self.order_account_map[order.order_id]=account_id
+        self._execute_trades(trades)
+        return order
+        
+    def _execute_trades(self, trades):
+        for i in trades:
+            self._execute_trade(i)
+
+    def _is_order_complete(self,order: Order):
+        return order.leaves_qty==0
+
+    def _execute_trade(self, trade: Trade):
+        account_id=self.order_account_map[trade.order_id]
+
+        # calculate price for trade fullfilment
+        full_price=trade.trade_price*trade.trade_qty
+        exprected_price=self.orders[trade.order_id].price*trade.trade_qty
+        price_diff=exprected_price-full_price
+        # add to order total
+        if trade.order_id not in self.order_total_price:
+            self.order_total_price[trade.order_id]=0
+
+        self.order_total_price[trade.order_id]+=full_price
+
+        # init escrow if needet
+        if trade.instmt not in self.escrow[account_id]:
+            self.escrow[account_id][trade.instmt]=0
+
+        # first edit escrow
+        if trade.trade_side==Side.BUY:
+            self.escrow[account_id][trade.instmt]+=trade.trade_qty
+            self.escrow[account_id][_bal]-=full_price
+            # move new resources to account
+            self._move_to_account(account_id,trade.instmt,trade.trade_qty)
+            # if deal was better then expected move money back
+            self._move_to_account(account_id,_bal,price_diff)
+        else:
+            self.escrow[account_id][trade.instmt]-=trade.trade_qty
+            self.escrow[account_id][_bal]+=full_price
+            # move new bal into account
+            self._move_to_account(account_id,_bal,full_price)
+        
+
+
+      
+
+        self.executed_trades.append(trade)
+        #update market rate
+        self.market_rate[trade.instmt]=trade.trade_price
+
+
+