""" bank11.py: Simulate customers arriving
    at random, using a Source, requesting service
    from two counters each with their own queue
    random servicetime.
    Uses a Monitor object to record waiting times
"""
from SimPy.Simulation  import *
from SimPy.SimPlot import *
from random import Random

class Bank11(SimPlot):
    def __init__(self,**p):
        SimPlot.__init__(self,**p)
    
    def NoInSystem(self,R):
        """ The number of customers in the resource R
        in waitQ and active Q"""
        return (len(R.waitQ)+len(R.activeQ))

    def model(self):
        self.counterRV = Random(self.params["counterseed"])
        self.sourceseed = self.params["sourceseed"]
        nrRuns=self.params["nrRuns"]
        self.lastLeave=0
        self.noRunYet=True
        for runNr in range(nrRuns):
            self.noRunYet=False
            self.Nc = 2
            self.counter = [Resource(name="Clerk0",monitored=False),
                            Resource(name="Clerk1",monitored=False)]
            self.waitMonitor = Monitor(name='Waiting Times')
            self.waitMonitor.xlab='Time'
            self.waitMonitor.ylab='Waiting time'
            self.serviceMonitor = Monitor(name='Service Times')
            self.serviceMonitor.xlab='Time'
            self.serviceMonitor.ylab='wait+service'
            initialize()
            source = Source(self,seed = self.sourceseed*1000)
            activate(source,source.generate(self.params["numberCustomers"],
                                            self.params["interval"]),0.0)
            simulate(until=self.params['endtime'])
            self.lastLeave+=now()
        print "%s run(s) completed"%(nrRuns)
        print("Parameters:\n%s"%self.params)

class Source(Process):
    """ Source generates customers randomly"""
    def __init__(self,modInst,seed=333):
        Process.__init__(self)
        self.modInst=modInst
        self.SEED = seed

    def generate(self,number,interval):       
        rv = Random(self.SEED)
        for i in range(number):
            c = Customer(self.modInst,name = "Customer%02d"%(i,))
            activate(c,c.visit(timeInBank=12.0))
            t = rv.expovariate(1.0/interval)
            yield hold,self,t

class Customer(Process):
    """ Customer arrives, is served and leaves """
    def __init__(self,modInst,**p):
        Process.__init__(self,**p)
        self.modInst=modInst
        
    def visit(self,timeInBank=0):       
        arrive=now()
        Qlength = [self.modInst.NoInSystem(self.modInst.counter[i])\
                   for i in range(self.modInst.Nc)]
        for i in range(self.modInst.Nc):
            if Qlength[i] ==0 or Qlength[i]==min(Qlength): join =i ; break
        yield request,self,self.modInst.counter[join]
        wait=now()-arrive
        self.modInst.waitMonitor.observe(wait,t=now())
        ##print "%7.4f %s: Waited %6.3f"%(now(),self.name,wait)
        tib = self.modInst.counterRV.expovariate(1.0/timeInBank)
        yield hold,self,tib
        yield release,self,self.modInst.counter[join]
        self.modInst.serviceMonitor.observe(now()-arrive,t=now())

root=Tk()
plt=Bank11()
plt.params={"endtime":2000,
       "sourceseed":1133,
       "counterseed":3939393,
       "numberCustomers":50,
       "interval":10.0,
       "trace":0,
       "nrRuns":1}
plt.model()
plt.plotLine(plt.waitMonitor,color='blue',width=2)
plt.plotLine(plt.serviceMonitor,color='red',width=2)
root.mainloop()