#!/usr/bin/perl

=comment

Copyright (c) 2003-2010, Andrew Dunstan

See accompanying License file for license details

=cut 

use strict;

use Digest::SHA1  qw(sha1_hex);
use MIME::Base64;
use DBI;
use DBD::Pg;
use Data::Dumper;
use Mail::Send;
use Storable qw(thaw);

use vars qw($dbhost $dbname $dbuser $dbpass $dbport
       $all_stat $fail_stat $change_stat $green_stat
       $default_host
);


use FindBin qw($RealBin);
require "$RealBin/BuildFarmWeb.pl";

die "no dbname" unless $dbname;
die "no dbuser" unless $dbuser;

# don't use configged dbuser/dbpass

$dbuser=""; $dbpass="";

my $dsn="dbi:Pg:dbname=$dbname";
$dsn .= ";host=$dbhost" if $dbhost;
$dsn .= ";port=$dbport" if $dbport;

my $db = DBI->connect($dsn,$dbuser,$dbpass);

die $DBI::errstr unless $db;

my $clear_old = $db->do(q[

    DELETE FROM alerts
    WHERE sysname IN
      (SELECT name FROM buildsystems WHERE no_alerts)
			   ]);


my $sth = $db->prepare(q[

    SELECT DISTINCT ON (sysname, branch) 
	 sysname, branch, 
	 extract(epoch from snapshot at time zone 'GMT')::int as snapshot, 
	 frozen_conf as config
    FROM build_status s join buildsystems b on (s.sysname = b.name)
    WHERE NOT b.no_alerts and
       snapshot > current_timestamp - interval '30 days'
    ORDER BY sysname, branch, snapshot desc

			  ]);

$sth->execute;

my @last_heard;

while (my $row = $sth->fetchrow_hashref)
{
    push(@last_heard, $row);
}

$sth->finish;

my $sql = q[

   SELECT sysname, branch, 
	    extract(epoch from first_alert) as first_alert, 
	    extract(epoch from last_notification) as last_notification
   FROM alerts

	    ];

my $alerts = $db->selectall_hashref($sql,['sysname','branch']);

my @need_cleared;
my @need_alerts;

my $clear_sth = $db->prepare(q[

  DELETE FROM alerts
  WHERE sysname = ?
  AND branch = ?
		      ]);

my $update_sth = $db->prepare(q[

  UPDATE alerts
  SET last_notification = timestamp '1970-01-01' + ( interval '1 second' * $1)
  WHERE sysname = $2
  AND branch = $3
		      ]);

my $insert_sth = $db->prepare(q[

  INSERT INTO alerts ( sysname, branch, first_alert, last_notification )
  VALUES ($1, $2,  
	  timestamp '1970-01-01' + ( interval '1 second' * $3),
	  timestamp '1970-01-01' + ( interval '1 second' * $4))
		      ]);


my $now = time;
my $lts = scalar(localtime);
print "starting alert run: $lts\n";

foreach my $sysbranch (@last_heard)
{
    my $client_conf = thaw $sysbranch->{config};

    my %client_alert_settings = %{ $client_conf->{alerts} || {} };
    my $setting = $client_alert_settings{$sysbranch->{branch}};
    unless ($setting && $setting->{alert_after} && $setting->{alert_every})
    {
	# if no valid setting, clear any alert and keep going
	if ($alerts->{$sysbranch->{sysname}}->{$sysbranch->{branch}})
	{
	    $clear_sth->execute($sysbranch->{sysname},$sysbranch->{branch});
	    push(@need_cleared,[$sysbranch]);
	}
	next;
    }
    # ok, we have valid settings. should the alert be on?
    my $hours_since_heard = ($now - $sysbranch->{snapshot}) / 3600;
    # yep
    print 
	"have settings for $sysbranch->{sysname}:$sysbranch->{branch} ",
	"hours since heard = $hours_since_heard, ",
	"setting = $setting->{alert_after} / $setting->{alert_every} \n";

    if ($hours_since_heard > $setting->{alert_after})
    {
	my $known_alert = 
	    $alerts->{$sysbranch->{sysname}}->{$sysbranch->{branch}};
	if ($known_alert && 
	    ($now - (3600 * $setting->{alert_every})) >
	    $known_alert->{last_notification})
	{
	    # check if it's too old - 15 days and twice initial seems plenty
	    if ($hours_since_heard > 360 && 
		     $hours_since_heard  > 2 * $setting->{alert_after} )
	    {
		print "alert is too old ... giving up\n";
		next;
	    }

	    # old alert, but time to alert again
	    print "alert is on, but time to alert again\n";
	    $update_sth->execute($now,
				 $sysbranch->{sysname},
				 $sysbranch->{branch},
				 );
	    push(@need_alerts,[$sysbranch,$setting]);
	    print "alert updated\n";
	}
	elsif ( ! $known_alert )
	{
	    # new alert
	    print "new alert needed\n";
	    $insert_sth->execute($sysbranch->{sysname},
				 $sysbranch->{branch},
				 $now,$now);
	    print "new record inserted\n";
	    push(@need_alerts,[$sysbranch,$setting]);
	}
    }
    # nope, so clear the alert if it exists
    elsif ($alerts->{$sysbranch->{sysname}}->{$sysbranch->{branch}})
    {
	print "clear exisiting alerts";
	$clear_sth->execute($sysbranch->{sysname},$sysbranch->{branch});
	push(@need_cleared,[$sysbranch,$setting]);
    }
    
}

print "start emails\n";

my $addr_sth = $db->prepare(q[

  SELECT owner_email
  FROM buildsystems
  WHERE name = ?
		 ]);


my $me = `id -un`; chomp $me;
my $host = `hostname`; chomp ($host);
$host = $default_host unless ($host =~ m/[.]/ || !defined($default_host));

my $from_addr = "Exim BuildFarm <$me\@$host>";
$from_addr =~ tr /\r\n//d;



foreach my $clearme (@need_cleared)
{
    my ($sysbranch, $setting) = @$clearme;
    my ($animal, $branch) = ($sysbranch->{sysname},$sysbranch->{branch});
    my $text;
    if ($setting)
    {
	my $hours = sprintf("%.2f",($now - $sysbranch->{snapshot}) / 3600);
	$text = "$sysbranch->{sysname} has now reported " .
	    "on $sysbranch->{branch} $hours hours ago.";
    }
    else
    {
	$text = "$sysbranch->{sysname} has lost alarm settings on branch: " .
	    "$sysbranch->{branch}. Resetting alarm to off.";
    }
    my $msg = new Mail::Send;

    $msg->set('From',$from_addr);

    $addr_sth->execute($animal);

    my $mailto = $addr_sth->fetchrow_array;

    print "sending clear to $mailto\n";

    # $sth->finish;

    $msg->to($mailto);
    $msg->subject("Exim BuildFarm member $animal Branch $branch Alert cleared");
    my $fh = $msg->open;
    print $fh "\n\n$text\n"; 
    $fh->close;

    print "alert cleared $animal $branch\n";
}

foreach my $needme (@need_alerts)
{
    my ($sysbranch, $setting) = @$needme;
    my ($animal, $branch) = ($sysbranch->{sysname},$sysbranch->{branch});
    my $hours = sprintf("%.2f",($now - $sysbranch->{snapshot}) / 3600);
    my $text = "$sysbranch->{sysname} has not reported " .
	"on $sysbranch->{branch} for $hours hours.";
    my $msg = new Mail::Send;

    $msg->set('From',$from_addr);

    $addr_sth->execute($animal);

    my ($mailto) = $addr_sth->fetchrow_array;

    # $sth->finish;

    print "sending alert to $mailto\n";

    $msg->to($mailto);

    $msg->subject("Exim BuildFarm member $animal Branch $branch " .
		  "Alert notification");
    my $fh = $msg->open;
    print $fh "\n\n$text\n"; 
    $fh->close;

    print "alert sent $animal $branch\n";
}


print "=================================\n";