#!/usr/bin/env python
#Blake VandeMerwe 9/27/2012 -- Program 2

from collections import OrderedDict as oDict
from collections import namedtuple

Segment = namedtuple('Segment', ['company', 'ticker', 'price', 'dollarChange', 'percentChange', 'ytdChange', 'w52high', 'w52low', 'peRatio'])

CHUNK_IDENT = 'Last updated'

class Observer(object):
    name = "Observer base"
    def update(self, data, dataChunk):
        raise NotImplementedError("Method not implemented")

class Average(Observer):
    name = "Average"
    oFile = "Average.dat"
    def update(self, data, dataChunk):
        with open(Average.oFile, 'a') as f:
            averagePrice = 0
            for s in dataChunk:
                averagePrice += float(s.price)
            averagePrice = averagePrice / len(dataChunk)
            f.write('%s, Average Price: %s\n' % (data, averagePrice))

class Change10(Observer):
    name = "Change10"
    oFile = "Change10.dat"
    def update(self, data, dataChunk):
        with open(Change10.oFile, 'a') as f:
            f.write('%s:\n' % (data))
            for s in dataChunk:
                if abs(float(s.percentChange)) > 10:
                    f.write('%s %s %s\n' % (s.ticker, s.price, s.percentChange))
            f.write('\n')

class Selections(Observer):
    name = "Selections"
    oFile = "Selections.dat"

    def __init__(self, toWatch = []):
        self.watch = toWatch

    def update(self, data, dataChunk):

        with open(Selections.oFile, 'a') as f:
            f.write('%s:\n' % (data))
            for s in dataChunk:
                if s.ticker in self.watch:
                    f.write('%s\n' % (' '.join([v for v in s]).strip()))
            f.write('\n')

class LocalStocks(object):
    def __init__(self, registers = []):
        self.data = oDict()
        self.observers = {}

        if registers: [self.register(r) for r in registers]

    def snapshot(self, data = ''):
        def _parseChunks(chunk = ''):
            newChunk = []
            for seg in chunk:
                seg = seg.split()[::-1]
                if len(seg) > 0:
                    newChunk.append(Segment(
                        peRatio = seg[0],
                        w52low = seg[1],
                        w52high = seg[2],
                        ytdChange = seg[3],
                        percentChange = seg[4],
                        dollarChange = seg[5],
                        price = seg[6],
                        ticker = seg[7],
                        company = ' '.join(seg[8:][::-1]).strip()))
            return newChunk

        chunks = oDict()
        chunk = ''

        for line in data:
            if CHUNK_IDENT in line:
                chunk = line.split(CHUNK_IDENT)[-1].strip()
            else:
                chunks.setdefault(chunk, []).append(line.strip())

        for c in chunks.keys():
            chunks[c] = _parseChunks(chunks[c])

        self.data = chunks
        self.notify()

    def register(self, observer):
        self.observers[observer.name] = observer

    def remove(self, observer):
        del self.observers[observer.name]

    def notify(self):
        delData = []
        for data in self.data.keys():
            delData.append(data)
            for o in self.observers.keys():
                self.observers[o].update(data, self.data[data])
        for d in delData:
            del self.data[d]

def main():
    LS = LocalStocks([Average(), Selections(['ALL', 'BA', 'BC', 'GBEL', 'KFT', 'MCD', 'TR', 'WAG']), Change10()])

    with open('ticker.dat') as f:
        LS.snapshot(f.readlines())

if __name__ == "__main__":
    main()