"""bank19_OO: Using priorities to increase the  clerks for long queues"""

## Model components ------------------------

from SimPy.SimulationTrace import *                                              

from random import expovariate,seed

class Source(Process):                                        
    """ Source generates customers randomly"""
    def generate(self,number,rate):       
        for i in range(number):
            c = Customer(name = "Customer%02d"%(i,),sim=self.sim)
            self.sim.activate(c,c.visit(timeInBank=12.0))
            yield hold,self,expovariate(rate)

class Customer(Process):                                      
    """ Customer arrives, is served and leaves """
    def visit(self,timeInBank):       
        print "%8.4f %s: Arrived     "%(self.sim.now(),self.name)

        yield request,self,self.sim.counter                            
        print "%8.4f %s: Got counter "%(self.sim.now(),self.name)
        tib = expovariate(1.0/timeInBank)
        yield hold,self,tib
        yield release,self,self.sim.counter
 
        print "%8.4f %s: Finished    "%(self.sim.now(),self.name)

class ClerkProcess(Process):                                 
    """ This process removes a clerk from the counter
    immediately."""
    def serverProc(self):                                    
        while True:                                          
            # immediately grab the clerk
            yield request,self,self.sim.counter,100                   
            print "%8.4f %s: leaves.  Free:"\
                  "%d, %d waiting"%(self.sim.now(),self.name,
                                    self.sim.counter.n,len(self.sim.counter.waitQ))
           
            def queuelong():                                              
                return len(self.sim.counter.waitQ) > 2
            yield waituntil,self, queuelong                  

            yield release,self,self.sim.counter                       
            print "%8.4f %s: needed .  Free:"\
                  "%d, %d waiting"%(self.sim.now(),self.name,
                                    self.sim.counter.n,len(self.sim.counter.waitQ))
            def queueshort():                                             
                return len(self.sim.counter.waitQ) == 0
            yield waituntil,self,queueshort                   

## Experiment data -------------------------

maxTime = 200.0    # minutes
tracing = 0 
## Model  ----------------------------------
if tracing:
    library=SimulationTrace
else:
    library=Simulation
    
class BankModel(library):                                     
    def run(self):
        self.initialize()
        self.counter = Resource(2,name="Clerk",qType=PriorityQ,sim=self)   
        clerk1 = ClerkProcess('Clerk',sim=self)                            
        self.activate(clerk1, clerk1.serverProc())                     
        source = Source('Source',sim=self)                              
        self.activate(source,source.generate(number=20,rate=0.1),at=0.0)  
        self.simulate(until=maxTime)                                     

#~ ## Experiment  ----------------------------------
seed(393939)
BankModel().run() 

