package SVN::Hooks::CheckJira;
# ABSTRACT: Integrate Subversion with the JIRA ticketing system.
$SVN::Hooks::CheckJira::VERSION = '1.31';
use strict;
use warnings;

use Carp;
use Data::Util qw(:check);
use SVN::Hooks;
use JIRA::Client;

use Exporter qw/import/;
my $HOOK = 'CHECK_JIRA';
our @EXPORT = qw/CHECK_JIRA_CONFIG CHECK_JIRA CHECK_JIRA_DISABLE/;


my ($BaseURL, $Login, $Passwd, $MatchLog, $MatchKey);
my $JIRA;
my @Checks;
my %Defaults = (
    require     => 1,
    valid       => 1,
    unresolved  => 1,
    by_assignee => 0,
);

sub CHECK_JIRA_CONFIG {
    ($BaseURL, $Login, $Passwd, $MatchLog, $MatchKey) = @_;

    if (defined $MatchKey) {
	is_rx($MatchKey) or croak "CHECK_JIRA_CONFIG: fifth argument must be a Regexp.\n";
    } else {
	$MatchKey = qr/[A-Z]{2,}/;
    }

    if (defined $MatchLog) {
	is_rx($MatchLog) or croak "CHECK_JIRA_CONFIG: fourth argument must be a Regexp.\n";
    } else {
	$MatchLog = qr/(.*)/;
    }

    @_ >= 3 && @_ <= 5
	or croak "CHECK_JIRA_CONFIG: requires three, four, or five arguments.\n";

    $BaseURL =~ s/\/+$//;

    return 1;
}


sub _validate_projects {
    my ($opt, $val) = @_;
    is_string($val) && $val =~ /^[A-Z,\s]+$/
	or croak "$HOOK: $opt\'s value must be a string matching /^[A-Z,\\s]+\$/.\n";
    my %projects = map {$_ => undef} grep {/./} split /\s*,\s*/, $val;
    return \%projects;
}

sub _validate_bool {
    my ($opt, $val) = @_;
    defined $val or croak "$HOOK: undefined $opt\'s value.\n";
    return $val;
}

sub _validate_code {
    my ($opt, $val) = @_;
    is_code_ref($val) or croak "$HOOK: $opt\'s value must be a CODE-ref.\n";
    return $val;
}

sub _validate_regex {
    my ($opt, $val) = @_;
    is_rx($val) or croak "$HOOK: $opt\'s value must be a qr/REGEX/.\n";
    return $val;
}

my %opt_checks = (
    projects          => \&_validate_projects,
    require           => \&_validate_bool,
    valid             => \&_validate_bool,
    unresolved        => \&_validate_bool,
    by_assignee       => \&_validate_bool,
    check_one         => \&_validate_code,
    check_all         => \&_validate_code,
    check_all_svnlook => \&_validate_code,
    post_action       => \&_validate_code,
    exclude           => \&_validate_regex,
);

sub CHECK_JIRA {
    my ($regex, $opts) = @_;
    is_rx($regex) || (is_string($regex) && $regex eq 'default')
	or croak "$HOOK: first arg must be a qr/Regexp/ or the string 'default'.\n";
    ! defined $opts || is_hash_ref($opts)
	or croak "$HOOK: second argument must be a HASH-ref.\n";

    $opts = {} unless defined $opts;
    foreach my $opt (keys %$opts) {
	exists $opt_checks{$opt} or croak "$HOOK: unknown option '$opt'.\n";
	$opts->{$opt} = $opt_checks{$opt}->($opt, $opts->{$opt});
    }

    if (ref $regex) {
	push @Checks, [$regex => $opts];
    } else {
	while (my ($opt, $val) = each %$opts) {
	    $Defaults{$opt} = $val;
	}
    }
    PRE_COMMIT(\&pre_commit);
    POST_COMMIT(\&post_commit) if exists $opts->{post_action};

    return 1;
}


my $Disabled;

sub CHECK_JIRA_DISABLE {
    $Disabled = 1;
}

sub _pre_checks {
    my ($svnlook, $keys, $opts) = @_;

    # Grok and check each JIRA issue
    my @issues;
    foreach my $key (@$keys) {
	my $issue = eval {$JIRA->getIssue($key)};
	if ($opts->{valid}) {
	    croak "$HOOK: issue $key is not valid: $@\n" if $@;
	}
	$issue or next;
	if ($opts->{unresolved}) {
	    croak "$HOOK: issue $key is already resolved.\n"
		if defined $issue->{resolution};
	}
	if ($opts->{by_assignee}) {
	    my $author = $svnlook->author();
	    croak "$HOOK: committer ($author) is different from issue ${key}'s assignee ($issue->{assignee}).\n"
		if $author ne $issue->{assignee};
	}
	if (my $check = $opts->{check_one}) {
	    $check->($JIRA, $issue, $svnlook);
	}
	push @issues, $issue;
    }

    if (my $check = $opts->{check_all}) {
	$check->($JIRA, @issues) if @issues;
    }

    if (my $check = $opts->{check_all_svnlook}) {
	$check->($svnlook, $JIRA, @issues) if @issues;
    }

    return;
}

sub _post_action {
    my ($svnlook, $keys, $opts) = @_;

    if (my $action = $opts->{post_action}) {
	$action->($JIRA, $svnlook, @$keys);
    }

    return;
}

sub _check_if_needed {
    my ($svnlook, $docheck) = @_;

    return if $Disabled;

    defined $BaseURL
	or croak "$HOOK: plugin not configured. Please, use the CHECK_JIRA_CONFIG directive.\n";

    my @files = $svnlook->changed();

    foreach my $check (@Checks) {
	my ($regex, $opts) = @$check;

	for my $file (@files) {
	    if ($file =~ $regex) {
		# skip exclusions
		next if exists $opts->{exclude} && $file =~ $opts->{exclude};

		# Grok the JIRA issue keys from the commit log
		my ($match) = ($svnlook->log_msg() =~ $MatchLog);
		my @keys    = defined $match ? $match =~ /\b$MatchKey-\d+\b/g : ();

		my %opts = (%Defaults, %$opts);

		if ($opts{require}) {
		    croak "$HOOK: you must cite at least one JIRA issue key in the commit message.\n"
			unless @keys;
		}

		return unless @keys;

		# Check if there is a restriction on the project keys allowed
		if (exists $opts->{projects}) {
		    foreach my $key (@keys) {
			my ($pkey, $pnum) = split /-/, $key;
			croak "$HOOK: issue $key is not allowed. You must cite only JIRA issues for the following projects: ", join(', ', sort keys %{$opts->{projects}}), ".\n"
			    unless exists $opts->{projects}{$pkey};
		    }
		}

		# Connect to JIRA if not yet connected.
		unless (defined $JIRA) {
		    $JIRA = eval {JIRA::Client->new($BaseURL, $Login, $Passwd)};
		    croak "CHECK_JIRA_CONFIG: cannot connect to the JIRA server: $@\n" if $@;
		}

		$docheck->($svnlook, \@keys, \%opts);
		last;
	    }
	}
    }

    return;
}

sub pre_commit {
    my ($svnlook) = @_;
    _check_if_needed($svnlook, \&_pre_checks);
    return;
}

sub post_commit {
    my ($svnlook) = @_;
    _check_if_needed($svnlook, \&_post_action);
    return;
}

1; # End of SVN::Hooks::CheckJira

__END__

=pod

=encoding UTF-8

=head1 NAME

SVN::Hooks::CheckJira - Integrate Subversion with the JIRA ticketing system.

=head1 VERSION

version 1.31

=head1 DESCRIPTION

This SVN::Hooks plugin requires that any Subversion commits affecting
some parts of the repository structure must make reference to valid
JIRA issues in the commit log message. JIRA issues are referenced by
their keys which consists of a sequence of uppercase letters separated
by an hyfen from a sequence of digits. E.g., CDS-123, RT-1, and
SVN-97.

It's active in the C<pre-commit> and/or the C<post-commit> hook.

It's configured by the following directives.

=head2 CHECK_JIRA_CONFIG(BASEURL, LOGIN, PASSWORD [, REGEXP [, REGEXP]])

This directive specifies how to connect and to authenticate to the
JIRA server. BASEURL is the base URL of the JIRA server, usually,
something like C<http://jira.example.com/jira>. LOGIN and PASSWORD are
the credentials of a JIRA user who has browsing rights to the JIRA
projects that will be referenced in the commit logs.

The fourth argument is an optional qr/Regexp/ object. It will be used
to match against the commit logs in order to extract the list of JIRA
issue keys. By default, the JIRA keys are looked for in the whole
commit log, which is equivalent to qr/(.*)/. Sometimes this can be
suboptimal because the user can introduce in the message some text
that inadvertently looks like a JIRA issue key whithout being so. With
this argument, the log message is matched against the REGEXP and only
the first matched group (i.e., the part of the message captured by the
first parenthesis (C<$1>)) is used to look for JIRA issue keys.

The fifth argument is another optional qr/Regexp/ object. It is used
to match JIRA project keys, which match qr/[A-Z]{2,}/ by
default. However, since you can specify different patterns for JIRA
project keys
(L<http://confluence.atlassian.com/display/JIRA/Configuring+Project+Keys>),
you need to be able to specify this here too.

The JIRA issue keys are extracted from the commit log (or the part of
it specified by the REGEXP) with the following pattern:
C<qr/\b([A-Z]+-\d+)\b/g>;

=head2 CHECK_JIRA(REGEXP => {OPT => VALUE, ...})

This directive tells how each part of the repository structure must be
integrated with JIRA.

During a commit, all files being changed are tested against the REGEXP
of each CHECK_JIRA directive, in the order that they were called. If
at least one changed file matches a regexp, the issues cited in the
commit log are checked against their current status on JIRA according
to the options specified after the REGEXP.

The available options are the following:

=over

=item projects => 'PROJKEYS'

By default, the commiter can reference any JIRA issue in the commit
log. You can restrict the allowed keys to a set of JIRA projects by
specifying a comma-separated list of project keys to this option.

=item require => [01]

By default, the log must reference at least one JIRA issue. You can
make the reference optional by passing a false value to this option.

=item valid => [01]

By default, every issue referenced must be valid, i.e., it must exist
on the JIRA server. You can relax this requirement by passing a false
value to this option. (Why would you want to do that, though?)

=item unresolved => [01]

By default, every issue referenced must be unresolved, i.e., it must
not have a resolution. You can relax this requirement by passing a
false value to this option.

=item by_assignee => [01]

By default, the commiter can reference any valid JIRA issue. Passing a
true value to this option you require that the commiter can only
reference issues to which she is the current assignee.

=item check_one => CODE-REF

If the above checks aren't enough you can pass a code reference
(subroutine) to this option. The subroutine will be called once for
each referenced issue with three arguments:

=over

=item the JIRA::Client object used to talk to the JIRA server.

=item the RemoteIssue object representing the issue.

=item the SVN::Look object used to grok information about the commit.

=back

The subroutine must simply return with no value to indicate success
and must die to indicate failure.

Plese, read the JIRA::Client and SVN::Look modules documentation to
understand how to use these objects.

=item check_all => CODE-REF

Sometimes checking each issue separatelly isn't enough. You may want
to check some relation among all the referenced issues. In this case,
pass a code reference to this option. It will be called once for the
commit. Its first argument is the JIRA::Client object used to talk to
the JIRA server. The following arguments are references to RemoteIssue
objects for every referenced issue. The last argument is the SVN::Look
object used to grok information about the commit. The subroutine must
simply return with no value to indicate success and must die to
indicate failure.

=item check_all_svnlook => CODE-REF

This check is the same as the previous one, except that the first
argument passed to the routine is the SVN::Look object used to grok
information about the commit. The rest of the arguments are the same.

=item post_action => CODE-REF

This is not a check, but an opportunity to perform some action after a
successful commit. The code reference passed will be called once
during the post-commit hook phase. Its first argument is the
JIRA::Client object used to talk to the JIRA server. The second
argument is the SVN::Look object that can be used to inspect all the
information about the commit proper.  The following arguments are the
JIRA keys mentioned in the commit log message. The value returned by
the routine, if any, is ignored.

=item exclude => REGEXP

Normally you specify a CHECK_JIRA with a regex matching a root
directory in the repository hierarchy. Sometimes you need to specify
some subparts of that root directory that shouldn't be treated by this
CHECK_JIRA directive. You can use this option to specify these
exclusions by means of another regex.

=back

You can set defaults for these options using a CHECK_JIRA directive
with the string C<'default'> as a first argument, instead of a
qr/Regexp/.

    # Set some defaults
    CHECK_JIRA(default => {
        projects    => 'CDS,TST',
        by_assignee => 1,
    });

    # Check if some commits are scheduled, i.e., if they reference
    # JIRA issues that have at least one fix version.

    sub is_scheduled {
        my ($jira, $issue, $svnlook) = @_;
        return scalar @{$issue->{fixVersions}};
    }
    CHECK_JIRA(qr/^(trunk|branches/fix)/ => {
        check_one   => \&is_scheduled,
    });

Note that you need to call CHECK_JIRA at least once with a qr/Regexp/
in order to trigger the checks. A call for (C<'default'> doesn't
count. If you want to change defaults and force checks for every
commit, do this:

    CHECK_JIRA(default => {projects => 'CDS'});
    CHECK_JIRA(qr/./);

The C<'post_action'> pseudo-check can be used to interact with the
JIRA server after a successful commit. For instance, you may want to
add a comment to each refered issue like this:

    # This routine returns a closure that can be passed to
    # post_action.  The closure receives a string to be added as a
    # comment to each issue refered to by the commit message. The
    # commit info can be interpolated inside the comment using the
    # SVN::Look method names inside angle brackets.

    sub add_comment {
        my ($format) = @_;
        return sub {
            my ($jira, $svnlook, @keys) = @_;
            # Substitute keywords in the input comment with calls
            # into the $svnlook reference
	    $format =~ s/\{(\w+)\}/"\$svnlook->$1()"/eeg;
            for my $key (@keys) {
                $jira->addComment($key, $format);
            }
        }
    }

    CHECK_JIRA(qr/./ => {
        post_action => add_comment("Subversion Commit r{rev} by {author} on {date}\n{log_msg}")
    });

You can use a generic CHECK_JIRA excluding specific directories from
it using the "exclude" option like this:

    CHECK_JIRA(qr:^(trunk|branches/[^/]): => {
        exclude => qr:/documentation/:,
        # other options...
    });

=head2 CHECK_JIRA_DISABLE

This directive globally disables all CHECK_JIRA directives. It's useful, for
instance, when your JIRA server must be taken down for maintenance and you
don't want to reject Subversion commits in this period.

=for Pod::Coverage post_commit pre_commit

=head1 AUTHOR

Gustavo L. de M. Chaves <gnustavo@cpan.org>

=head1 COPYRIGHT AND LICENSE

This software is copyright (c) 2015 by CPqD <www.cpqd.com.br>.

This is free software; you can redistribute it and/or modify it under
the same terms as the Perl 5 programming language system itself.

=cut
