import csv

from cofollow import consumer
from tableformat import create_formatter
from ticker import Ticker


@consumer
def to_csv(target):
    def producer():
        while True:
            yield line

    reader = csv.reader(producer())
    while True:
        line = yield
        target.send(next(reader))


@consumer
def create_ticker(target):
    while True:
        row = yield
        target.send(Ticker.from_row(row))


@consumer
def negchange(target):
    while True:
        record = yield
        if record.change < 0:
            target.send(record)


@consumer
def ticker(fmt, fields):
    formatter = create_formatter(fmt)
    formatter.headings(fields)
    while True:
        rec = yield
        row = [getattr(rec, name) for name in fields]
        formatter.row(row)


if __name__ == '__main__':
    from cofollow import follow

    follow(
        'Data/stocklog.csv',
        to_csv(
            create_ticker(
                negchange(
                    ticker('text', ['name', 'price', 'change'])
                )
            )
        )
    )