#!/usr/bin/env perl
# vim:ts=4:sw=4:expandtab
#
# © 2010-2011 Michael Stapelberg and contributors
#
# syntax: ./complete-run.pl --display :1 --display :2
# to run the test suite on the X11 displays :1 and :2
# use 'Xdummy :1' and 'Xdummy :2' before to start two
# headless X11 servers
#

use strict;
use warnings;
use EV;
use AnyEvent;
use IO::Scalar; # not in core :\
use File::Temp qw(tempfile tempdir);
use v5.10;
use DateTime;
use Data::Dumper;
use Cwd qw(abs_path);
use Proc::Background;
use TAP::Harness;
use TAP::Parser;
use TAP::Parser::Aggregator;
use File::Basename qw(basename);
use AnyEvent::I3 qw(:all);
use Try::Tiny;
use Getopt::Long;
use Time::HiRes qw(sleep);
use X11::XCB::Connection;

# install a dummy CHLD handler to overwrite the CHLD handler of AnyEvent / EV
# XXX: we could maybe also use a different loop than the default loop in EV?
$SIG{CHLD} = sub {
};

# reads in a whole file
sub slurp {
    open my $fh, '<', shift;
    local $/;
    <$fh>;
}

my $coverage_testing = 0;
my @displays = ();

my $result = GetOptions(
    "coverage-testing" => \$coverage_testing,
    "display=s" => \@displays,
);

@displays = split(/,/, join(',', @displays));
@displays = map { s/ //g; $_ } @displays;

@displays = qw(:1) if @displays == 0;

# connect to all displays for two reasons:
# 1: check if the display actually works
# 2: keep the connection open so that i3 is not the only client. this prevents
#    the X server from exiting (Xdummy will restart it, but not quick enough
#    sometimes)
my @conns;
my @wdisplays;
for my $display (@displays) {
    try {
        my $x = X11::XCB::Connection->new(display => $display);
        push @conns, $x;
        push @wdisplays, $display;
    } catch {
        say STDERR "WARNING: Not using X11 display $display, could not connect";
    };
}

my $i3cmd = abs_path("../i3") . " -V -d all --disable-signalhandler";
my $config = slurp('i3-test.config');

# 1: get a list of all testcases
my @testfiles = @ARGV;

# if no files were passed on command line, run all tests from t/
@testfiles = <t/*.t> if @testfiles == 0;

# 2: create an output directory for this test-run
my $outdir = "testsuite-";
$outdir .= DateTime->now->strftime("%Y-%m-%d-%H-%M-%S-");
$outdir .= `git describe --tags`;
chomp($outdir);
mkdir($outdir) or die "Could not create $outdir";
unlink("latest") if -e "latest";
symlink("$outdir", "latest") or die "Could not symlink latest to $outdir";

# 3: run all tests
my @done;
my $num = @testfiles;
my $harness = TAP::Harness->new({ });

my $aggregator = TAP::Parser::Aggregator->new();
$aggregator->start();

my $cv = AnyEvent->condvar;

# We start tests concurrently: For each display, one test gets started. Every
# test starts another test after completing.
take_job($_) for @wdisplays;

#
# Takes a test from the beginning of @testfiles and runs it.
#
# The TAP::Parser (which reads the test output) will get called as soon as
# there is some activity on the stdout file descriptor of the test process
# (using an AnyEvent->io watcher).
#
# When a test completes and @done contains $num entries, the $cv condvar gets
# triggered to finish testing.
#
sub take_job {
    my ($display) = @_;
    my ($fh, $tmpfile) = tempfile();
    say $fh $config;
    say $fh "ipc-socket /tmp/nested-$display";
    close($fh);

    my $test = shift @testfiles;
    return unless $test;
    my $logpath = "$outdir/i3-log-for-" . basename($test);
    my $cmd = "export DISPLAY=$display; exec $i3cmd -c $tmpfile >$logpath 2>&1";
    my $dont_start = (slurp($test) =~ /# !NO_I3_INSTANCE!/);

    my $process = Proc::Background->new($cmd) unless $dont_start;
    say "[$display] Running $test with logfile $logpath";

    sleep 0.5;
    my $kill_i3 = sub {
        # Don’t bother killing i3 when we haven’t started it
        return if $dont_start;

        # When measuring code coverage, try to exit i3 cleanly (otherwise, .gcda
        # files are not written) and fallback to killing it
        if ($coverage_testing) {
            my $exited = 0;
            try {
                say "Exiting i3 cleanly...";
                i3("/tmp/nested-$display")->command('exit')->recv;
                $exited = 1;
            };
            return if $exited;
        }

        say "[$display] killing i3";
        kill(9, $process->pid) or die "could not kill i3";
    };

    my $output;
    my $parser = TAP::Parser->new({
        exec => [ 'sh', '-c', "DISPLAY=$display /usr/bin/perl -It/lib $test" ],
        spool => IO::Scalar->new(\$output),
        merge => 1,
    });

    my @watchers;
    my ($stdout, $stderr) = $parser->get_select_handles;
    for my $handle ($parser->get_select_handles) {
        my $w;
        $w = AnyEvent->io(
            fh => $handle,
            poll => 'r',
            cb => sub {
                # Ignore activity on stderr (unnecessary with merge => 1,
                # but let’s keep it in here if we want to use merge => 0
                # for some reason in the future).
                return if defined($stderr) and $handle == $stderr;

                my $result = $parser->next;
                if (defined($result)) {
                    # TODO: check if we should bail out
                    return;
                }

                # $result is not defined, we are done parsing
                say "[$display] $test finished";
                close($parser->delete_spool);
                $aggregator->add($test, $parser);
                push @done, [ $test, $output ];

                $kill_i3->();

                undef $_ for @watchers;
                if (@done == $num) {
                    $cv->send;
                } else {
                    take_job($display);
                }
            }
        );
        push @watchers, $w;
    }
}

$cv->recv;

$aggregator->stop();

for (@done) {
    my ($test, $output) = @$_;
    say "output for $test:";
    say $output;
}

# 4: print summary
$harness->summary($aggregator);