#!/usr/bin/env python

# Copyright (c) 2014 The Chromium OS Authors. All rights reserved.
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.

# This script is to be run daily to report machine utilization stats across
# each board and pool.


import argparse
from datetime import date
from datetime import datetime
from datetime import timedelta

import common
from autotest_lib.client.common_lib import global_config
from autotest_lib.client.common_lib import time_utils
from autotest_lib.client.common_lib.cros.graphite import stats
from autotest_lib.server.cros.dynamic_suite import frontend_wrappers
from autotest_lib.site_utils import host_history_utils


INSTANCE_SERVER = global_config.global_config.get_config_value(
        'SERVER', 'hostname', type=str)
_AFE = frontend_wrappers.RetryingAFE(
        server=INSTANCE_SERVER, timeout_min=60, delay_sec=0)

def report_stats(board, pool, start_time, end_time, span):
    """Report machine stats for given board, pool and time period.

    @param board: Name of board.
    @param pool: Name of pool.
    @param start_time: start time to collect stats.
    @param end_time: end time to collect stats.
    @param span: Number of hours that the stats should be collected for.
    """
    print '================ %-12s %-12s ================' % (board, pool)
    history = _AFE.run('get_host_history', board=board, pool=pool,
                       start_time=start_time, end_time=end_time)
    if not history:
        print 'No history found.'
        return
    status_intervals = host_history_utils.get_status_intervals(history)
    stats_all, num_hosts = host_history_utils.aggregate_hosts(
            status_intervals)
    total = 0
    total_time = span*3600*num_hosts
    for status, interval in stats_all.iteritems():
        total += interval
    if abs(total - total_time) > 10:
        print ('Status intervals do not add up. No stats will be collected for '
               'board: %s, pool: %s, diff: %s' %
               (board, pool, total - total_time))
        return

    mur = host_history_utils.get_machine_utilization_rate(stats_all)
    mar = host_history_utils.get_machine_availability_rate(stats_all)

    stats.Gauge('machine_utilization_rate').send('%s_hours.%s.%s' %
                                                 (span, board, pool), mur)
    stats.Gauge('machine_availability_rate').send('%s_hours.%s.%s' %
                                                  (span, board, pool), mar)
    stats.Gauge('machine_idle_rate').send('%s_hours.%s.%s' %
                                          (span, board, pool), mar-mur)

    for status, interval in stats_all.iteritems():
        print '%-18s %-16s %-10.2f%%' % (status, interval,
                                         100*interval/total_time)
    print 'Machine utilization rate  = %-4.2f%%' % (100*mur)
    print 'Machine availability rate = %-4.2f%%' % (100*mar)


def main():
    """main script. """
    parser = argparse.ArgumentParser()
    parser.add_argument('--span', type=int, dest='span',
                        help=('Number of hours that stats should be collected. '
                              'If it is set to 24, the end time of stats being '
                              'collected will set to the mid of the night. '
                              'Default is set to 1 hour.'),
                        default=1)
    options = parser.parse_args()

    labels = _AFE.get_labels(name__startswith='board:')
    boards = [label.name[6:] for label in labels]

    pools = ['bvt', 'suites', 'try-bot', 'cq', 'pfq']

    if options.span == 24:
        today = datetime.combine(date.today(), datetime.min.time())
        end_time = time_utils.to_epoch_time(today)
    else:
        now = datetime.now()
        end_time = datetime(year=now.year, month=now.month, day=now.day,
                            hour=now.hour)
        end_time = time_utils.to_epoch_time(end_time)

    start_time = end_time - timedelta(hours=options.span).total_seconds()
    print ('Collecting host stats from %s to %s...' %
           (time_utils.epoch_time_to_date_string(start_time),
            time_utils.epoch_time_to_date_string(end_time)))

    for board in boards:
        for pool in pools:
            report_stats(board, pool, start_time, end_time, options.span)


if __name__ == '__main__':
    main()