#!/usr/bin/env python
"""
needResources.py

Demo of waitUntil capability.

Scenario:
Three workers require sets of tools to do their jobs. Tools are shared, scarce
resources for which they compete.
"""
from SimPy.Simulation import *
from waitUntil import *
import random

class Worker(Process):
    def work(self,heNeeds=[]):
        def workerNeeds():
            for item in heNeeds:
                if item.n==0:
                    return False
            return True
                     
        while now()<8*60:
            while not workerNeeds():
                waitUntil(self,workerNeeds)
                yield passivate,self
            for item in heNeeds:
                yield request,self,item
            print "%s %s has %s and starts job" %(now(),self.name,
                [x.name for x in heNeeds])
            yield hold,self,random.uniform(10,30)
            for item in heNeeds:
                yield release,self,item
            yield hold,self,2 #rest
    
initialize()
brush=Resource(capacity=1,name="brush")
ladder=Resource(capacity=2,name="ladder")
hammer=Resource(capacity=1,name="hammer")
saw=Resource(capacity=1,name="saw")
painter=Worker("painter")
activate(painter,painter.work([brush,ladder]))
roofer=Worker("roofer")
activate(roofer,roofer.work([hammer,ladder,ladder]))
treeguy=Worker("treeguy")
activate(treeguy,treeguy.work([saw,ladder]))
simulate(until=9*60,callback=test)