#!/usr/bin/env python3

import argparse
import datetime
import os
import sys

from time import mktime


def read_line(log, date=None):
    while True:
        line = log["fp"].readline().strip()
        if not line:
            raise EOFError
        time = datetime.datetime.strptime(
            " ".join(line.split()[3:5]), "[%d/%b/%Y:%H:%M:%S +0000]"
        )
        if date is not None and time.strftime("%Y-%m-%d") != date:
            continue
        log["time"] = time
        log["line"] = line
        log["linenum"] += 1
        break


def combine_logs(logfiles, date=None):
    logs = []
    for logfile in logfiles:
        if os.stat(logfile).st_size == 0:
            continue
        logs.append(
            {"fp": open(logfile, "r"), "line": None, "linenum": 0, "time": None}
        )
        try:
            read_line(logs[-1], date)
        except EOFError:
            del logs[-1]

    while True:
        if len(logs) == 0:
            break
        logs = sorted(logs, key=lambda x: x["time"])
        print(logs[0]["line"])
        try:
            read_line(logs[0], date)
        except EOFError:
            del logs[0]


def date_now():
    return datetime.datetime.now()


if __name__ == "__main__":
    try:
        parser = argparse.ArgumentParser()
        parser.add_argument("-d", "--date", default=None)
        parser.add_argument("logfiles", nargs="+")
        args = parser.parse_args()
        if args.date is not None:
            if args.date == "today":
                date = date_now().strftime("%Y-%m-%d")
            elif args.date == "yesterday":
                date = (date_now() - datetime.timedelta(days=1)).strftime("%Y-%m-%d")
            else:
                date = args.date
        combine_logs(args.logfiles, date=date)
    except KeyboardInterrupt:
        sys.ext(1)