#!/usr/bin/perl -w

# Movable Type (r) Open Source (C) 2001-2012 Six Apart, Ltd.
# This program is distributed under the terms of the
# GNU General Public License, version 2.
#
# $Id$

package MT::Tool::ReportSlowRequest;
use strict;

use lib "./lib";
use base qw( MT::Tool );

use List::Util qw( min );
use Time::HiRes qw( time );
use MT;
use MT::Util::LogProcessor;
use Data::Dumper;

my ($arg_day, $arg_logdir, $arg_sample, $arg_slow, $arg_debug, $arg_dump);

sub help {
    return q{
        --logdir <dir>    Look for logs in directory <dir>. By default, logs
                          in the current directory are analyzed.
        --sample <num>    ?
        --slow <secs>     Number of seconds after which a request is listed
                          as one of the slowest. By default, requests over 2
                          seconds are considered the slowest.
        --day <name>      The name of the day to examine; either 'today',
                         'yesterday', or a date in the format YYYY-MM-DD.
        --debug           Enable debugging output.
        --dump            ?
    };
}

sub usage {
}

sub options {
    return (
        'logdir=s' => \$arg_logdir,
        'sample=i' => \$arg_sample,
        'slow=i'   => \$arg_slow,
        'day=s'    => \$arg_day,
        'debug'    => \$arg_debug,
        'dump'     => \$arg_dump,
    );
}

sub main {
    my $class = shift;
    my ($verbose) = $class->SUPER::main(@_);

    $arg_slow ||= 2;

    my $proc = MT::Util::LogProcessor->new(
        {
            debug        => $arg_debug,
            logdir       => $arg_logdir || '.',
            sample       => $arg_sample,
            day          => $arg_day || 'yesterday',
            file_pattern => 'pl-\d{8}.log',
        }
    );

    my %stash = ( today => $proc->day );
    my ( $total_records, $elapsed ) = $proc->process_log_files(
        sub {
            my ($rec) = @_;

            my $secs = int $rec->{time_total};

            my $bucket = $secs > 10 ? 10 : $secs;
            $stash{by_seconds}[$bucket]++;

            $stash{total_requests}++;

            if ( $secs > $arg_slow - 1 ) {
                push @{ $stash{slow} }, $rec;
            }
        }
    );

    printf "Processed %d records in %.02f seconds; speed: %.02f recs/sec\n",
      $total_records, $elapsed, $total_records / ( $elapsed || 1 )
      if $arg_debug;

    for my $bucket ( 0 .. $#{ $stash{by_seconds} } ) {
        my $count = $stash{by_seconds}[$bucket] || 0;
        $stash{restime_histogram}[$bucket] = {
            count => $count,
            range => $bucket == 10
            ? '10+ sec'
            : $bucket . '-' . ( $bucket + 1 ) . 's',
            percent => int( $count / $stash{total_requests} * 100 ) || 1,
        };
    }

    $stash{slow} =
      [ sort { $b->{time_total} <=> $a->{time_total} } @{ $stash{slow} || [] } ];

    report( \%stash );
}

sub report {
    my ($stash) = @_;

    print "Response time histogram:\n";
    for my $row ( @{ $stash->{restime_histogram} } ) {
        printf "%s: %s (%s%%)\n", $row->{range}, $row->{count}, $row->{percent};
    }

    print "Slowest requests:\n";
    for my $row ( @{ $stash->{slow} } ) {
        printf "%s\n", $row->{url};
        for my $key ( keys %$row ) {
            next if $key !~ /^time_/;
            my $secs = $row->{$key};
            next
              if $key eq 'time_mem_start'
              || $key eq 'time_mem_end'
              || $key eq 'time_total'
              || $secs < 0.01;
            printf "%s: %s\n", $key, $secs;
        }
    }
}

__PACKAGE__->main() unless caller;

1;

