#!/bin/sh
# -*-perl-*-
# ====================================================================== #
# Run the right perl version:
if [ -x /usr/local/bin/perl ]; then
  perl=/usr/local/bin/perl
elif [ -x /usr/bin/perl ]; then
  perl=/usr/bin/perl
else
  perl=`which perl| sed 's/.*aliased to *//'`
fi

exec $perl -x -S $0 "$@"     # -x: start from the following line
# ====================================================================== #
#! /Good_Path/perl -w
# line 17
#
# Name:   pencil-test
# Description:
#   Run the pencil code's auto test on some remote host(s) and wrap
#   results in HTML if required. Can be used from crontab.
# Usage:
#   pencil-test [options] host1 [host2 [host3 ..]]
#   pencil-test -l [options]
# Options:
#   -h, --help                -- Help
#   -l, --local               -- Run on the local host
#   -L, --lock                -- Run at maximum one instance per host
#   -H, --html                -- Write output as elementary HTML (mostly <pre>)
#   -X, --xml                 -- Write output as XML
#   -u, --update              -- Update everything before compiling
#   -r, --reload              -- Do 'touch RELOAD' after every time step
#   -s, --short               -- Use short directory names
#   -c, --clean               -- 'make cleann' before compiling
#   -D <DIR>,
#       --pencil-home=<DIR>   -- set PENCIL_HOME directory to DIR
#   -N <N>, --nice=<N>        -- Run tests with nice value of <N>
#   -i <file>,
#       --infofile=<file>     -- After last test, print content of <file>
#   -m <emaillist>,
#       --mail=<emaillist>    -- Specify who to send mail to if tests fail
#   -M <mailer>,
#      --Mailer=<mailer>      -- Specify e-mail program to use
#   -p <PP>,
#       --postproc=<PP>       -- Use postprocessor <PP> for output from make
#       --script-tests=TYPES  -- Run script tests matching TYPES, a
#                                comma-separated list of types
#                                'type1,type2,...', or a map
#                                (comma-separated list of colon-separated
#                                associations
#                                'type1:interp1,type2:interp2,...'. Use
#                                'DEFAULT' to get all configured types
#                                with their default interpreters
#   -t <limit>,
#       --time-limit=<limit>  -- Limit total time for each {start,run}.x phase
#   -T <file>,
#       --timings-file=<file> -- Append timings to <file>
#   -b
#       --use-pc_auto-test    -- Run pc_auto-test as backend, not auto-test
#                                (mnemonic: compile with 'build', not 'make').
#                                Eventually, this will become the default.
#   -Wa,<options>
#       --auto-test-options=<options>
#                             -- Pass <options> to pc_auto-test. If <options>
#                                contains commas, it is split into multiple
#                                options at the commas
#       --log-dir=<dir>       -- Directory to store the logfiles (default: .)
#       --previous-dir=<dir>  -- Directory for logfiles of the previous run (default: off)
#
# Email list syntax:
#   -m '{-:fluxrings},defaulty@any.where,nosy@some.where{+:fluxrings,+:rad1},ignorant@else.where{-:hydro.*}'
#   will not send mail if 'interlocked-fluxrings' fails -- except for Nosy
#   who explicitly requested this. Ignorant will not get emails if only 'hydro1'
#   or 'hydrogen-bond' fail. Note that the patterns are anchored at the end,
#   but not at the beginning.
# Sample crontab entry:
#   30 02 * * *  cd $HOME/pencil-auto-test && svn up && bin/pencil-test --clean --html --mail=my@email.net --nice=15 --reload --short --timings-file=$HOME/public_html/autotest_timings.txt > $HOME/public_html/autotest.html

use strict;
use POSIX qw(strftime);
use Getopt::Long;
use IPC::Open2;
use constant SUCCESS => 1;      # return value

my (%opts);                     # Variables written by GetOptions
my (%emails, %pos, %neg, %sendmailto); # Info on mailing if tests fail

## Process command line
my $commandline = $0.' '.join (' ', @ARGV);
eval {
    Getopt::Long::config("bundling");
};
GetOptions(\%opts,
           qw( -h   --help
                    --debug
               -v   --version
               -l   --local
               -L   --lock
               -H   --html
               -X   --xml
               -u   --update
               -U
               -r   --reload
               -s   --short
               -c   --clean
               -D=s --pencil-home=s
               -N=s --nice=s
               -i=s --infofile=s
               -m=s --mail=s
               -M=s --Mailer=s
               -p=s --postproc=s
                    --script-tests=s
               -t=s --time-limit=s
               -T=s --timings-file=s
                    --tag-stable
               -b   --use-pc_auto-test
               -W=s --auto-test-options=s
                    --log-dir=s
                    --previous-dir=s
               )) or die "Aborting.\n";
die '$Id$ ' . "\n"
            if    ($opts{'v'} || $opts{'version'});
die usage() if    ($opts{'h'} || $opts{'help'});
my $debug       = (              $opts{'debug'}       || 0 );
my $html        = ($opts{'H'} || $opts{'html'}        || 0 );
my $local       = ($opts{'l'} || $opts{'local'}       || 0 );
my $lock        = ($opts{'L'} || $opts{'lock'}        || 0 );
my $clean       = ($opts{'c'} || $opts{'clean'}       || 0 );
my $pencil_home = ($opts{'D'} || $opts{'pencil-home'} || '$PENCIL_HOME' || `pwd`);
my $nice        = ($opts{'N'} || $opts{'nice'}        || 0 );
my $infofile    = ($opts{'i'} || $opts{'infofile'}    || '' );
my $update      = ($opts{'u'} || $opts{'update'}      || $opts{'U'}  || 0 ); # keeping -U for backwards compatibility
my $reload      = ($opts{'r'} || $opts{'reload'}      || 0 );
my $short       = ($opts{'s'} || $opts{'short'}       || 0 );
my $tag_stable  = (              $opts{'tag-stable'}  || 0 );
my $emails      = ($opts{'m'} || $opts{'mail'}        || '');
my $mailer      = ($opts{'M'} || $opts{'Mailer'}      || '');
my $postproc    = ($opts{'p'} || $opts{'postproc'}    || '');
my $script_tests = (             $opts{'script-tests'} || '');
my $time_limit  = ($opts{'t'} || $opts{'time-limit'}  || '');
my $timingsfile = ($opts{'T'} || $opts{'timings-file'}|| '');
my $with_xml    = ($opts{'x'} || $opts{'xml'}         || '');
my $use_build   = ($opts{'b'} || $opts{'use-pc_auto-test'} || '');
my $log_dir     = (              $opts{'log-dir'}          || '');
my $previous_dir = (             $opts{'previous-dir'}     || '');

my @auto_test_options = ();
if (defined $opts{'W'}) {
    if ($opts{'W'} =~ /^Wa,(.*)/) {
        my $autotest_opts = $1;
        $autotest_opts =~ s/^\'(.*)\'$/$1/s;
        push @auto_test_options, split(/\s*,\s*/, $autotest_opts);
    } else {
        die "Unknown option <-".$opts{'W'}.">\n";
    }
}
if (defined $opts{'auto-test-options'}) {
    $opts{'auto-test-options'} =~ s/^\'(.*)\'$/$1/s;
    push @auto_test_options, split(/\s*,\s*/, $opts{'auto-test-options'});
}

my $blurb = "[This message was automatically generated by the 'pencil-test' script]\n";
my ($xml);

# Too few or too many arguments?
if ($local) {
    die "No host arguments allowed with -l option.\n" if (@ARGV);
} else {
    die usage() unless (@ARGV);
}

# Make sure we have /usr/sbin in path (which is where sendmail is often located)
$ENV{PATH} = "$ENV{PATH}:/usr/sbin" unless ($ENV{PATH} =~ m{(^|:)/usr/sbin($|:)});

if ($lock) {
    # Do not make a mess if another pencil-test is already running on this machine!
    my $instances_running = `ps aux | grep -v "grep" | grep "perl" | grep "$0" | wc -l`;
    $instances_running =~ s/\s+$//s;
    if ($instances_running > 1) { die ("ERROR: another 'pencil-test' is already running here!\n"); }
}

# Make a backup of the previous logfile directory
if ($log_dir && $previous_dir) {
    $log_dir =~ s|/+$||s;
    $previous_dir =~ s|/+$||s;
    my $exclude = '--exclude "index.html"';
    my $sub_dir = substr $previous_dir, 0, length($log_dir);
    if ($sub_dir eq $log_dir) {
        $sub_dir = substr $previous_dir, length($log_dir)+1;
        $exclude .= ' --exclude "'.$sub_dir.'"';
    }
    system('rsync -auq --del '.$exclude.' "'.$log_dir.'/" "'.$previous_dir.'/"');
    # Move previous logfile in place
    if (-f "$previous_dir/index-last.html") {
        system('mv -f "'.$previous_dir.'/index-last.html" "'.$previous_dir.'/index.html"');
    }
}

# Immediate flushing after "\n"
$| = 1;

print_header();

## Run test(s)
my $first = 1;
if ($local) {
    run_tests_on(`hostname`);
} else {
    foreach my $host (@ARGV) {
        run_tests_on($host)
    }
}

print_footer();

# Prepare previous logfile for next run...
if ($log_dir && $previous_dir) {
    system('cp -pf "'.$log_dir.'/index.html" "'.$log_dir.'/index-last.html"');
}

# ====================================================================== #

sub run_tests_on {
# Run auto tests remotely (unless $local is true) on the given host
    my ($host) = @_;
    chomp $host;

    print STDERR "run_test_on($host)" if ($debug);

    my ($shost) = ($host =~ /([^.]*)/); # host name without domain
    $shost = "\u$shost";

    if ($html) {
        unless ($first) { print "<p>\n<hr>\n<p>\n" };
        print "<h2>$shost:</h2>\n\n<pre>\n";
    } else {
        unless ($first) { print "\n\n" };
        print "  $host:\n================\n";
    }

    ## Construct and execute remote command
    my @cmd;
    if ($local) {
        @cmd = ("sh");
    } else {
        @cmd = ("ssh", "-x", "$host", "sh");
    }
    my $remcmd = build_remote_cmd();

    if ($debug) { print STDERR "open2(*POUT, *PIN, \"@cmd\")\n" };
    open2(*POUT, *PIN, "@cmd");
    if ($debug) { print STDERR "print PIN $remcmd\n" };
    print PIN "$remcmd\n";
    close PIN;
    if ($timingsfile ne '') {
        open(TIMINGS, ">> $timingsfile")
          or warn "Couldn't open $timingsfile for writing\n";
    }
    my ($line,$timings,$result,$update_error,$empty,$failures);
    $empty = 0;
    $failures = 0;
    while (defined($line=<POUT>)) {
        # Extract timing lines
        if ($line =~ /^#TIMING\s+(.*)/) {
            print "<$line>\n" if ($debug);
            print TIMINGS "$1\n";
            next;
        }

        # Extract maintainers line
        if ($line =~ /Maintainers of failed tests:\s*(.*?)\s*$/) {
            parse_maintainers($1);
        }

        # Identify errors
        if ($line =~ /^UPDATE ERROR:/) {
            $update_error = 1;
        }

        if ($html) {
            # Mark beginning of a test in HTML
            if ($empty && ($line =~ /^\s*(?:[^:\/]+\/)*\/*samples(?:\/([^:\/\s][^:\s]*))+: \(\d+\/\d+\)\s*$/is)) {
                print "</pre>\n".'<a name="'.$1.'"></a>'."\n<pre>";
            }
            if ($empty && ($line =~ /^\s*(?:All .*? tests? succeeded\.|\#*\s*auto-test failed\s*\#*)\s*$/is)) {
                print "</pre>\n".'<a name="summary"></a>'."\n<pre>";
            }
            $empty = 0;
            if ($line =~ /^[\s\-]*$/s) { $empty = 1; }

            # Links on failures summary in HTML
            if ($failures != 0) {
                if ($failures < 0) {
                    print "</pre>\n<ul>\n";
                    $failures = -$failures;
                }
                if ($line =~ /^\s+([^:\/\s][^:\s]*)\s+\(([^\(\)]+)\)\s*$/is) {
                    $result .= $line;
                    print '<li><a href="#'.$1.'"><code>'.$1.'</code></a> <code>('.$2.')</code>'."\n";
                    $failures--;
                    if ($failures <= 0) { print "</ul>\n<pre>"; }
                    next;
                }
                else {
                    $failures = 0;
                    print "</ul>\n<pre>";
                }
            }
            if ($line =~ /^\s*Failed (\d+) test\(s\) out of \d+:\s*$/is) {
                $failures = -$1;
            }
        }

        # Print all other lines
        print $line;
        $result .= $line;
    }
    close POUT;
    if ($timingsfile ne '') {
        close TIMINGS;
    }

    if ($result =~ /^(?:Test|All [0-9]+ tests) succeeded\./m) {
        # All performed tests were successful
        mark_all_succeeded($host);
        # Create a stable tag, if requested
        tag_stable_on_success($result,$host) if ($tag_stable);
    }
    else {
        # Output last fully successful auto-test
        my $last = "LAST_SUCCESS";
        if ($log_dir) { $last = $log_dir."/".$last; }
        print "----------------------------------------------------------------------\n";
        if (-e $last) {
            print "\nLast fully successful auto-test was:\n";
            system ('cat "'.$last.'"');
            print scalar localtime `stat -L --format="%Y" "$last"`;
            print "\n\n----------------------------------------------------------------------\n";
        }
        # Some tests had errors => send emails
        notify_on_error($result,$shost,$update_error);
    }

    $first = 0;
}
# ---------------------------------------------------------------------- #
sub build_remote_cmd {
# Construct the command to send to the remote host

    my $remcmd = "cd $pencil_home; ";
    if ($update) {
        $remcmd .= ''
          . 'if [ -e .git ]; then'  # .git can be a directory or a file
          . '    (git stash -q -u || echo "UPDATE ERROR: git stash");'
          . '    (git fetch -q || echo "UPDATE ERROR: git fetch");'
          # . '    (git reset -q --hard @{u} || echo "UPDATE ERROR: git reset");'
          . '    (git pull --rebase -q || echo "UPDATE ERROR: git pull");'
          . '    printf "Updated to git revision %s\n" $(git rev-parse HEAD);'
          . 'elif [ -d .svn ]; then'
          . '    (svn -q update || echo "UPDATE ERROR: svn update failed");'
          . 'else'
          . '    echo "UPDATE ERROR: Neither git nor svn checkout";'
          . '    false;'
          . 'fi;'
    }
    if ($use_build) {
        $remcmd .= "env PENCIL_HOME=$pencil_home ./bin/pc_auto-test ";
    } else {
        $remcmd .= "env PENCIL_HOME=$pencil_home ./bin/auto-test ";
    }
    $remcmd .= "--time ";
    if ($emails)             { $remcmd .= "--list-maintainers "; }
    if ($with_xml)           { $remcmd .= "--xml " };
    if ($clean)              { $remcmd .= "--clean " };
    if ($reload)             { $remcmd .= "--reload " };
    if ($short)              { $remcmd .= "--short " };
    if ($nice)               { $remcmd .= "--nice=$nice " };
    if ($infofile ne '')     { $remcmd .= "--infofile=$infofile " };
    if ($postproc)           { $remcmd .= "--postproc=\"$postproc\" " };
    if ($script_tests ne '') { $remcmd .= "--script-tests=\"$script_tests\" " };
    if ($time_limit ne '')   { $remcmd .= "--time-limit=\"$time_limit\" " };
    if ($timingsfile ne '')  { $remcmd .= "--summarize-times " };
    if ($log_dir)            { $remcmd .= "--log-dir=\"$log_dir\" " };
    if (@auto_test_options)  { $remcmd .= "@auto_test_options; "};

    return $remcmd;
}
# ---------------------------------------------------------------------- #
sub print_header {

    my $date = scalar localtime();
    my $xml = "";
    my $testname = "Pencil Code auto-test";

    $testname = $1." - ".$testname if ($commandline =~ /--pencil-home=['"]?[^'"\s]+?([^\/]+?)['"]?(\s|$)/is);

    if ($with_xml) {
        $xml=<<"END_XMLHEAD";
<?xml version="1.0" encoding="utf-8"?>
<pc_penciltest version="0.1" xmlns:media="http://www.nordita.dk/software/pencil-code/penciltest">
<timestamp type="start">$date</timestamp>
END_XMLHEAD
    }
    if ($html) {
        print <<"END_HEAD";
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html lang="en">
<head>
        <meta name="language" content="en">
        <meta http-equiv="content-type" content="text/html; charset=UTF-8" >
        <title>$testname</title>
</head>
<body>

<p>$date</p>
<pre>$commandline</pre>
END_HEAD
    } else {
        print "$date\n\n";
    }
}
# ---------------------------------------------------------------------- #
sub print_footer {

    my $date = scalar localtime();
    if ($html) {
        print <<"END_FOOT";
</pre>
$date
</body>
</html>
END_FOOT
    }
    if ($with_xml) {
        $xml.=<<"END_XMLFOOT";
<timestamp type="end">$date</timestamp>
</pc_penciltest>
END_XMLFOOT
    }
}
# ---------------------------------------------------------------------- #
sub usage {
# Extract description and usage information from this file's header.
    my $thisfile = __FILE__;
    local $/ = '';              # Read paragraphs
    open(FILE, "<$thisfile") or die "Cannot open $thisfile\n";
    while (<FILE>) {
        next unless /^\s*#\s*Usage:/m; # Paragraph _must_ contain 'Usage:'
        # Drop 'Author:', etc:
        s/.*?\n(\s*\#\s*(Description|Usage):\s*\n.*)/$1/s;
        # Don't print comment sign:
        s/^\s*\# ?//mg;
        last;
    }
    $_;
}
# ---------------------------------------------------------------------- #
sub mark_all_succeeded {
## Save revision of last fully successful auto-test
    my $host = (shift || '');

    if (!$local) { die "Not yet implemented to determine revision number on remote host:\n$host\n"; }

    my $result;
    my $revision = "";
    my $hash = "";
    if (-d "$pencil_home/.svn") {
        # SVN revision
        $revision = `svn info --show-item revision`;
        # GIT hash
        $result = `svn log -l 1 --with-revprop git-commit --xml "$pencil_home"`;
        if ($result =~ /name\s*=\s*"git-commit"\s*>(.*?)<\/property>/is) { $hash = $1; }
        if (!$hash) { $hash = "No network connection to github!"; }
    }
    elsif (-e "$pencil_home/.git") {
        # GIT hash
        $hash = `git log -1 --format=format:"%H"`;
        $revision = "please use SVN checkout!";
    }
    else {
        warn "Marking of last fully successful auto-test not possible without SVN or GIT!\n";
        return;
    }
    chomp ($revision, $hash);

    # Output information on last fully successful auto-test
    print "\nSVN: ".$revision."\n";
    print "GIT: ".$hash."\n\n";

    # Save information on last fully successful auto-test
    my $last = "LAST_SUCCESS";
    if ($log_dir) { $last = $log_dir."/".$last; }
    open (LAST, ">$last") or die "Error while writing '$last' file: $!\n";
    print LAST "SVN: ".$revision."\n";
    print LAST "GIT: ".$hash."\n";
    close (LAST) or die "Error while closing '$last' file: $!\n"
}
# ---------------------------------------------------------------------- #
sub tag_stable_on_success {
## Create a stable tag if auto-test was successful
    my $result = (shift || '');
    my $host   = (shift || '');
    my $date = strftime ("%Y-%m-%d", localtime);

    return if ($result =~ /^Failed ([0-9]+) test/m);

    my $cmd = "";
    if (-d "$pencil_home/.svn") {
        # SVN tagging
        $cmd = "svn copy ^/trunk ^/tags/stable_".$date." -m \"automatic validation completed: auto-test on $host\" > /dev/null";
    }
    elsif (-e "$pencil_home/.git") {
        # GIT tagging
        warn "Stable tagging not implemented yet for GIT!\n";
        return;
    }
    else {
        warn "Stable tagging not possible without SVN or GIT!\n";
        return;
    }

    # execute on remote host, if requested
    if (!$local) { $cmd = "ssh -x -n $host 'cd \$PENCIL_HOME;".$cmd."'"; }

    # execute tagging command
    system ($cmd);
}
# ---------------------------------------------------------------------- #
sub notify_on_error {
## Check for errors and send emails
    my ($result, $host, $update_error) = @_;

    my $failed_marker = '### auto-test failed ###'; # only in version of
                                                    # auto-test later than
                                                    # 27-Feb-2006

    return SUCCESS unless ($emails or $update_error);  # nobody to report to

    my $failed = ($result =~ /^### auto-test failed ###$/m);
    print STDERR "\$failed (1) = <$failed>\n" if ($debug);
    my $nerrors = 0;
    if ($result =~ /^Failed ([0-9]+) test/m) { # get number of failed tests
        $failed = 1;
        $nerrors = $1;
    }
    if ($debug) {
        print STDERR "Update error\n" if $update_error;
        print STDERR "\$failed (2) = <$failed>\n";
        print STDERR "\$nerrors    = <$nerrors>\n";
        print STDERR "\$result     = <$result>\n";
    }

    return SUCCESS unless ($failed or $update_error); # nothing to report

    # Analyze
    parse_emails($emails);      # ..so we can filter out individual tests
    my ($main,$summary)
      = split(/^----*\s*\n(?:$failed_marker\s*\n)?(?=Failed)/m,$result);
    if (defined($summary)) {
        # Extract list of failed directories
        my @failures = split(/\n/,$summary);
        ($nerrors) = ($failures[0] =~ /Failed ([0-9]+) test/);
        @failures = grep /^\s*\S+\s\(.*\)\s*$/, @failures;
        @failures = map { $_ =~ s/^\s*(\S*).*/$1/; $_ } @failures;
        foreach my $address (keys %emails) {
            foreach my $fail (@failures) {
                my $def_matches = ! any_match($fail,$neg{''});
                my $pos_matches = any_match($fail,$pos{$address});
                my $neg_matches = any_match($fail,$neg{$address});
                if (($def_matches || $pos_matches) && ! $neg_matches) {
                    if ($debug) {
                        print STDERR "...", substr($fail,-35,35),
                          ": \$sendmailto{$address}++\n";
                    }
                    $sendmailto{$address}++;
                }
            }
        }
    } elsif ($update_error) {
        warn "[Couldn't update code]\n";
        $summary = 'Failed to update the code';
        $nerrors = '';
        %sendmailto = %emails;  # Report this to everybody
    } else {
        warn "[No individual failing tests to report]\n";
        $summary = '';
        $nerrors = '';
        %sendmailto = %emails;  # Report this (probably another auto-test
                                # running) to everybody
    }

    # Send mail
    foreach my $address (keys %sendmailto) {
        send_mail($address,$mailer,$host,$nerrors,$blurb,$summary);  #,$main);
    }
}
# ---------------------------------------------------------------------- #
sub write_timings {
## Append timing results to file
    my ($timings, $file) = @_;

    if (defined $timings) {
        print TIMINGS $timings;
        close(TIMINGS);
    }
}

# ---------------------------------------------------------------------- #
sub parse_emails {
# Parse the email list into hashes
    my $emaillist = shift;

    my ($entry,$address,$spec);
    print STDERR "Checking who to alert by email\n" if ($debug);
    while ($emaillist) {
        $emaillist =~ /^([^\}\{,]*(?:\{[^\}]*\})?),?(.*)/
          or warn "Cannot parse email list <$emaillist>\n";
        ($entry,$emaillist) = ($1,$2);
        ($address,$spec) = ($entry =~ /([^\}\{]*)\{?([^\}]*)\}?/);
        $emails{$address}++ if ($address =~ /\S/);
        foreach my $sp (split(/,/,$spec)) {
            if ($sp =~ /^\-:(.*)/) {
                push @{$neg{$address}}, $1
#               push @{$neg{$1}}, $address;
            } elsif ($sp =~ /^\+:(.*)/) {
                push @{$pos{$address}}, $1
#               push @{$pos{$1}}, $address;
            } else {
                warn "Strange specification: <$spec>\n";
            }
        }
    }
}
# ---------------------------------------------------------------------- #
sub parse_maintainers {
# Parse the email list into hashes
    my ($maintainers) = @_;

    print STDERR "Maintainers of failed test: $maintainers\n" if ($debug);

    foreach my $address (split(/\s*,\s*/, $maintainers)) {
        $address = deobfuscate($address);
        $emails{$address}++ if ($address =~ /\S/);
    }
}
# ---------------------------------------------------------------------- #
sub any_match {
# Match a string against a list of patterns
    my $string = shift;
    my $pattern_pointer = shift;
    my @patterns = ();

    if (ref($pattern_pointer) eq 'ARRAY') {
        @patterns = @{$pattern_pointer}
    };

    foreach my $patt (@patterns) {
        if ($string =~ /$patt$/) { return 1; }
    }
    return 0;
}
# ---------------------------------------------------------------------- #
sub send_mail {
# Send an email to the given address
    my $address = shift;
    my $mailer  = shift;
    my $host    = shift;
    my $nerrors = shift;
    my @text    = grep /./, @_;

    if (! $mailer) {
        if (in_PATH("sendmail")) {
            $mailer = "sendmail";
        } elsif (in_PATH("mailx")) {
            $mailer = "mailx";
        } else {
            $mailer = "mail";
        }
    }

    print STDERR "\$mailer = $mailer\n" if ($debug);

    my $errmsg;
    if ($nerrors =~ /[0-9]+/) { # number of failing individual tests
        my $plurals = ($nerrors<=1 ? '' : 's');
        $errmsg = "$nerrors error$plurals";
    } else {                    # most likely: lockfile exists
        $errmsg = "There are errors";
    }

    my $subject = "$errmsg from pencil-code autotest on $host";

    # Add Reply-To: field if we have enough information
    my $reply_to = undef;
    my $mail = my $email = $ENV{EMAIL};
    if (defined($email)) {
        $email = deobfuscate($email);
        if ($email =~ /<([^>]*)>/) {
            $mail = $1;
        } else {
            $mail = $email;
        }
        if ($mail =~ /[-.a-zA-Z_0-9]+\@[-.a-zA-Z_0-9]+/) {
            $reply_to = $email;
        }
    }

    my $sep = "\n" . "-" x 70 . "\n\n";
    my $body = join($sep, @text);

    send_mail_dispatch($mailer, $address, $subject, $reply_to, $body);
}
# --------------------------------------------------------------------- #
sub send_mail_dispatch {
# Send email with a mailer that understands mail/mailx conventions
# ('mailx -s Subject reci@pi.ent')
    my ($mailer, @rest) = @_;

    my %dispatch_table = (
                          'sendmail'      => \&send_mail_sendmail,
                          'mailx'         => \&send_mail_mailx,
                          'mail'          => \&send_mail_mailx,
                          'debug'         => \&send_mail_debug,
                          'debug-to-file' => \&send_mail_debug_files,
                     );
    my $mailer_name = $mailer;
    $mailer_name =~ s{.*/}{};
    my $method = $dispatch_table{$mailer_name};
    if (defined($method)) {
        &$method($mailer, @rest);
    } else {
        warn "ERROR: No such mailer: $mailer\n";
    }

    if ($debug) {
        &send_mail_debug('debug', @rest);
    }

}

# --------------------------------------------------------------------- #
sub send_mail_mailx {
# Send email with a mailer that understands mail/mailx conventions
# ('mailx -s Subject reci@pi.ent')
    my ($mailer, $address, $subject, $reply_to, $body) = @_;

    my @cmdline = ($mailer);
    push @cmdline, '-s', $subject;
    push @cmdline, "$address";

    if ($debug) { print STDERR "\@cmdline = @cmdline\n" };
    open (MAILER, '|-', @cmdline);
    print MAILER $body;
    print MAILER "\n";
    close MAILER;
}
# --------------------------------------------------------------------- #
sub send_mail_sendmail {
# Send email with sendmail
    my ($mailer, $address, $subject, $reply_to, $body) = @_;

    my @cmdline = ($mailer, '-oi', '-t');

    if ($debug) { print STDERR "\@cmdline = @cmdline\n" };
    open (MAILER, '|-', @cmdline);
    print MAILER "To: $address\n";
    print MAILER "Subject: $subject\n";
    print MAILER "Reply-to: $reply_to\n" if defined($reply_to);
    print MAILER "\n\n";      # header--body separator
    print MAILER "$body\n";
    close MAILER;
}
# --------------------------------------------------------------------- #
sub send_mail_debug {
# Don't send email -- just tell us what would be sent, in a format
# inspired by sendmail
    my ($mailer, $address, $subject, $reply_to, $body) = @_;

    print STDERR "email: To: $address\n";
    print STDERR "email: Subject: $subject\n";
    if (defined($reply_to)) {
        print STDERR "email: Reply-to: $reply_to\n";
    } else {
        print STDERR "email: <No Reply-to: field>\n";
    }
    print STDERR "email: \n";
    print STDERR "email: \n";
    print STDERR "email: $body\n";
}
# --------------------------------------------------------------------- #
sub send_mail_debug_files {
# Don't send email -- just tell us what would be sent, in a format
# inspired by sendmail
    my ($mailer, $address, $subject, $reply_to, $body) = @_;

    my $file = "debug_$address";
    open(my $fh, "> $file") or die "Cannot open file $file: $!\n";
    print $fh "email: To: $address\n";
    print $fh "email: Subject: $subject\n";
    if (defined($reply_to)) {
        print $fh "email: Reply-to: $reply_to\n";
    } else {
        print $fh "email: <No Reply-to: field>\n";
    }
    print $fh "email: \n";
    print $fh "email: \n";
    print $fh "email: $body\n";
}
# ---------------------------------------------------------------------- #
sub deobfuscate {
# Return obfuscated email to mailer-compliant form
    my ($address) = @_;

    $address =~ s{/|\[at\]|@}{@};
    $address =~ s{:|\[dot\]|\.}{.}g;

    return $address;
}
# --------------------------------------------------------------------- #
sub in_PATH {
# Check whether an executable is available in the execution PATH
    my $file = shift;
    my $path;
    foreach $path (split(/:/,$ENV{PATH})) {
        if (-x "$path/$file") { return 1; }
    }
    return 0;
}
# ---------------------------------------------------------------------- #

# End of file pencil-test