#format python
"""LacOperon symbolic simulation using [Python] --[yong27], 2005-03-27
"""
import unittest, sys

class LacOperon:
    ID = 0
    isBindOperator = True
    isBindCap = False
    def __init__(self, feed):
        self.feed = feed
        self.check()
        self.ID = LacOperon.ID
        LacOperon.ID+=1

    def check(self):
        if self.feed.lactose > 0:
            self.isBindOperator = False
        if self.feed.glucose == 0:
            self.isBindCap = True

    def update(self):
        if self.feed.isBottom():
            raise AssertionError, "Die"
        if self.feed.glucose > 0:
            self.feed.glucose -=1
        elif self.getProtein() =='lactase':
            self.feed.lactose -=1
        self.check()

    def getProtein(self):
        if not self.isBindOperator and self.isBindCap:
            return "lactase"

    def __repr__(self):
        return '%i : glucose %i,  lactose %i,  proteins %s'%(
                self.ID, self.feed.glucose, self.feed.lactose, 
                self.getProtein())

class Feed:
    def __init__(self, **substrates):
        self.glucose = substrates['glucose']
        self.lactose = substrates['lactose']
    def isBottom(self):
        return self.glucose == 0 and self.lactose == 0

class Simulator:
    def __init__(self):
        self.players = list()
    def addPlayer(self, player):
        self.players.append(player)

    def iterate(self, n):
        for each in range(n):
            for player in self.players:
                print player
                player.update()


class FeedTest(unittest.TestCase):
    def testGetGlucose(self):
        f = Feed(glucose=10,lactose=10)
        self.assertEquals(10 , f.glucose)

class LacOperonTest(unittest.TestCase):
    def testOnlyGlucose(self):
        lo = LacOperon(Feed(glucose=10, lactose=0))
        self.assertEquals(None, lo.getProtein())

    def testOnlyLactose(self):
        lo = LacOperon(Feed(glucose=0, lactose=10))
        self.assertEquals('lactase', lo.getProtein())

    def testGlucoseLactose(self):
        lo = LacOperon(Feed(glucose=10, lactose=10))
        self.assertEquals(None, lo.getProtein())

    def testUpdate(self):
        lo = LacOperon(Feed(glucose=2, lactose=2))
        lo.update()
        self.assertEquals(1, lo.feed.glucose)
        self.assertEquals(2, lo.feed.lactose)
        lo.update()
        self.assertEquals(0, lo.feed.glucose)
        self.assertEquals(2, lo.feed.lactose)
        lo.update()
        self.assertEquals(0, lo.feed.glucose)
        self.assertEquals(1, lo.feed.lactose)
        lo.update()
        self.assertEquals(0, lo.feed.glucose)
        self.assertEquals(0, lo.feed.lactose)
        self.assertRaises(AssertionError, lo.update)


def simulate():
    s = Simulator()
    l1 = LacOperon(Feed(glucose=10, lactose=10))
    l2 = LacOperon(Feed(glucose=15, lactose=5))
    s.addPlayer(l1)
    s.addPlayer(l2)
    try:
        s.iterate(30)
    except AssertionError:
        print 'die.'
        sys.exit()

if __name__=='__main__':
    #unittest.main(argv=('','-v'))
    simulate()