#!/usr/bin/env python

#    Copyright (c) 2007, Corey Goldberg (corey@goldb.org)
#
#    This file is part of PerfLog.
#
#    PerfLog is free software; you can redistribute it and/or modify
#    it under the terms of the GNU General Public License as published by
#    the Free Software Foundation; either version 2 of the License, or
#    (at your option) any later version.


import time


class TimeSeries(object):
    def __init__(self, data_set, interval, parse=True):
    # data_set is a list of tuples: (epoch_time, datapoint)
    # interval is in secs
    
        self.data_set = self.__sort_epoch(data_set)
        self.interval = interval
        self.epoch_start = data_set[0][0]
        self.epoch_finish = data_set[len(data_set) - 1][0]
        self.date_time_start = self.__convert_from_epoch(self.epoch_start)
        self.date_time_finish = self.__convert_from_epoch(self.epoch_finish)
        self.timespan = self.epoch_finish - self.epoch_start
        if parse:
            self.series = self.__make_series()
            self.counts = self.__count_series()
        
        
    def __make_series(self):
        series = []
        current_marker = self.epoch_start
        next_marker = self.epoch_start + self.interval
        while current_marker <= self.epoch_finish:
            series.append([timeval[1] for timeval in self.data_set if current_marker <= timeval[0] < next_marker])
            current_marker = next_marker
            next_marker += self.interval
        return series
    
    
    def __count_series(self):
        counts = [len(x) for x in self.series]
        return counts
        
        
    def __sort_epoch(self, data_set):
        data_set.sort(cmp=lambda x, y: cmp(x[0], y[0]))
        return data_set
    
    
    def __convert_from_epoch(self, epoch):
        date_time = time.strftime('%m-%d-%Y %H:%M:%S', time.gmtime(epoch))
        return date_time