#!/usr/bin/env perl
#############################################################################
##
## Copyright (C) 2013 Digia Plc and/or its subsidiary(-ies).
## Contact: http://www.qt-project.org/legal
##
## Script for generating a Graphviz (.gv) file from Jira bugreports.
## Might not work for any other Jira DB than the Qt Project bugreports DB.
##
## $QT_BEGIN_LICENSE:LGPL$
## Commercial License Usage
## Licensees holding valid commercial Qt licenses may use this file in
## accordance with the commercial license agreement provided with the
## Software or, alternatively, in accordance with the terms contained in
## a written agreement between you and Digia.  For licensing terms and
## conditions see http://qt.digia.com/licensing.  For further information
## use the contact form at http://qt.digia.com/contact-us.
##
## GNU Lesser General Public License Usage
## Alternatively, this file may be used under the terms of the GNU Lesser
## General Public License version 2.1 as published by the Free Software
## Foundation and appearing in the file LICENSE.LGPL included in the
## packaging of this file.  Please review the following information to
## ensure the GNU Lesser General Public License version 2.1 requirements
## will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
##
## In addition, as a special exception, Digia gives you certain additional
## rights.  These rights are described in the Digia Qt LGPL Exception
## version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
##
## GNU General Public License Usage
## Alternatively, this file may be used under the terms of the GNU
## General Public License version 3.0 as published by the Free Software
## Foundation and appearing in the file LICENSE.GPL included in the
## packaging of this file.  Please review the following information to
## ensure the GNU General Public License version 3.0 requirements will be
## met: http://www.gnu.org/copyleft/gpl.html.
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## $QT_END_LICENSE$
##
#############################################################################

use strict;
use warnings;

package Qt::Jira2Gv;


=head1 NAME

jira2gv - generates a Graphviz (.gv) file from a Jira issue

=head1 SYNOPSIS

 jira2gv <--server URL> <--issue JiraIssue> [--verbose] [--cache]
         [--edgeExtra JiraIssue=<valule>] [--issueStop JiraIssue]

This script fetches hierarchical Jira items and generates a Graphviz graph.
It will only display outward dependencies (so sub-tasks and "depends on" links) on a task.

=head1 OPTIONS

=over

=item --verbose, -v

Be verbose. Will print a statement for each issue fetched from Jira.

=item --cache, -c

Read or create cached items.  This will make the script store each Jira item fetched, and use it
the next time around you run the script. Very useful for debugging, but don't use it on production
system, as you'll never get updated issues.

=item --server <url-base>

HTTP address of the server to fetch Jira issues from.

=item --issue <JIra issue identifier>

Jira issue identifier of the issue to start the graph from.

=item --edgeExtra <Jira issue identifier>='['<Edge extra data>']'

Adds edge extra data to any edge going to the prefixed Jira issue. Be sure to include the [].

Example: --edgeExtra JIRA-1234=[minlen=2]

=item --issueStop <Jira issue identifier>

Don't generate sub-graph passed this Jira issue.

=back

B<EXAMPLES:>

=over

Generate a graph from the Qt Project's bug-tracker, showing tasks left for the Qt 5 release:

jira2gv --server https://bugreports.qt-project.org --issue QTBUG-20885 --edgeExtra QTBUG-24203=[minlen=2] --edgeExtra QTBUG-24131=[minlen=3]

=back

=cut

use XML::Simple;
use LWP::Simple;
use HTML::Entities;
use Data::Dumper;
use Switch;
use Text::Wrap   qw(wrap $columns fill);
use Pod::Usage   qw(pod2usage);
use Getopt::Long qw(GetOptionsFromArray );
use POSIX        qw(strftime);

sub parse_arguments
{
    my ($self, @args) = @_;

    %{$self} = (%{$self},
        'verbose'             => 0,
        'doCaching'           => 0,
        'jiraServer'          => "" ,
        'jiraIssue'           => "" ,
        'jiraStopIssues'      => {},
        'gvEdgeExtra'        => {},
        'allOpenIssues'       => {},
        'totalItems'          => 0,
        'remainingIssues'     => [],
    );

    GetOptionsFromArray(\@args,
        'verbose|v'         =>  \$self->{qw{ verbose           }},
        'cache|c'           =>  \$self->{qw{ doCaching         }},
        'server=s'          =>  \$self->{qw{ jiraServer        }},
        'issue=s'           =>  \$self->{qw{ jiraIssue         }},
        'edgeExtra=s%'      =>  \$self->{qw{ gvEdgeExtra      }},
        'issueStop=s'       =>  sub {
            my ($opt, $val) = @_;
            $self->{'jiraStopIssues'}{$val} = 1;
        },
        'help|?'            =>  sub { pod2usage(1); },
    ) || pod2usage(2);

    die "Need to specify a server!" if (!$self->{jiraServer});
    die "Need to specify an issue!" if (!$self->{jiraIssue});

    return;
}

sub createGvItem
{
    my ($self, $item_ref) = @_;

    my $result = "";
    my $id = $item_ref->{'key'}->{'content'};

    my $description = $item_ref->{'summary'};
    $description = wrap("", "", "$description");
    encode_entities($description);
    $description =~ s/\n/<BR \/>/g;

    my $assignee = $item_ref->{'assignee'}->{'content'};
    encode_entities($assignee);

    my $priority = $item_ref->{'priority'}->{'content'};
    my $color;
    switch ($priority) {
        case /^P0/ { $color = "firebrick" }
        case /^P1/ { $color = "red" }
        case /^P2/ { $color = "gold" }
        case /^P3/ { $color = "forestgreen" }
        case /^Not/ { $color = "lightgrey" }
        else       { $color = "steelblue" }
    }

    $result .= "\"$id\" [shape=none,margin=0,color=\"$color\","
             . "label=<<TABLE ALIGN=\"LEFT\" BORDER=\"1\" CELLBORDER=\"0\" COLOR=\"black\">"
             . "<TR><TD ALIGN=\"LEFT\"><B>$id</B></TD><TD ALIGN=\"CENTER\"><B>"
             . $priority . "</B></TD><TD ALIGN=\"RIGHT\">"
             . $assignee . "</TD></TR>";
    $result .= "<TR><TD ALIGN=\"LEFT\" colspan=\"3\">"
             . $description . "</TD></TR></TABLE>>]\n";
    $result .= "\"$id\" [tooltip=\"$id ($priority for $assignee)\", URL=\"" . $item_ref->{'link'} . "\"]\n";

    return $result;
}

sub fetchIssue
{
    my ($self, $issue) = @_;

    my $gvContent = "";
    print "fetching $issue..." if ($self->{verbose});

    my $content;
    if ($self->{doCaching} && -e "$issue.xml") {
        open FILE, "<$issue.xml";
        $content = do { local $/; <FILE> };
        close FILE;
    } else {
        my $url = $self->{jiraServer} . '/si/jira.issueviews:issue-xml/' . $issue . '/' . $issue . '.xml';
        $content = get($url) || die "Couldn't download $issue from $self->{jiraServer}! (using $url)";
        open FILE, ">$issue.xml";
        print FILE $content;
        close FILE;
    }
    my $ref = XMLin($content);

#    if ($issue eq "QTBUG-24203" || $issue eq "QTBUG-20885") {
#        open FILE, ">$issue.pl";
#        print FILE Dumper($ref);
#        close FILE;
#    }
    my $taskStatus = $ref->{'channel'}->{'item'}->{'status'}->{'content'};

    # Ignore tasks which are already closed or resolved
    if ($taskStatus eq "Closed" || $taskStatus eq "Resolved" ) {
        print "[- $taskStatus -]\n" if ($self->{verbose});
        return "";
    }

    $gvContent .= $self->createGvItem($ref->{'channel'}->{'item'});
    print "[done!]\n" if ($self->{verbose});

    # Check if this is a task we stop at, then don't dive into sub-tasks here
    my $stopIssue = $self->{'jiraStopIssues'}->{$issue};
    if (!$stopIssue) {
        # Push each sub-task of this task to the issueLinks hash
        my $sref = $ref->{'channel'}->{'item'}->{'subtasks'}->{'subtask'};
        if ($sref->{'content'}) {
                push(@{$self->{'issueLinks'}{$issue}}, $sref->{'content'});
                $gvContent .=  $self->fetchIssue($sref->{'content'});

        } else {
            foreach my $item (keys %{$sref}) {
                my $subissue = $sref->{$item}->{'content'};
                push(@{$self->{'issueLinks'}{$issue}}, $subissue);
                $gvContent .=  $self->fetchIssue($subissue);
            }
        }

        # Push each outward linke of this task to the issueLinks hash
        if (exists $ref->{'channel'}->{'item'}->{'issuelinks'}->{'issuelinktype'}->{'outwardlinks'}) {
            my $iref = $ref->{'channel'}->{'item'}->{'issuelinks'}->{'issuelinktype'}->{'outwardlinks'}->{'issuelink'};
            if (ref($iref) eq "ARRAY") {
                foreach my $item_ref (@{$ref->{'channel'}->{'item'}->{'issuelinks'}->{'issuelinktype'}->{'outwardlinks'}->{'issuelink'}}) {
                    my $subissue = $item_ref->{'issuekey'}->{'content'};
                    push(@{$self->{'issueLinks'}{$issue}}, $subissue);
                    $gvContent .=  $self->fetchIssue($subissue);
                }
            } elsif (ref($iref) eq "HASH") {
                my $subissue = $iref->{'issuekey'}->{'content'};
                push(@{$self->{'issueLinks'}{$issue}}, $subissue);
                $gvContent .=  $self->fetchIssue($subissue);
            }
        }
    }

    ++$self->{'totalItems'};
    $self->{'allOpenIssues'}{$issue} = 1;
    return $gvContent;
}

sub fetchAllRelatedIssues
{
    my ($self, $issue) = @_;
    push (@{$self->{'remainingIssues'}}, $issue);

    my $gvContent = "";
    while(@{$self->{'remainingIssues'}}) {
        $gvContent .= $self->fetchIssue(shift(@{$self->{'remainingIssues'}}));
    }
    return $gvContent;
}

sub calculateDependencies()
{
    my ($self) = @_;

    my $gvContent = "";
    #print Dumper(\$self->{'issueLinks'});
    my $ref = $self->{'gvEdgeExtra'};
    foreach my $key (keys %{$self->{'issueLinks'}}) {
        if ($self->{'allOpenIssues'}{$key}) {
            foreach my $subissue (@{$self->{'issueLinks'}{$key}}) {
                my $special = $ref->{$subissue};
                $special = "" if (!$special);
                $gvContent .= "\"$key\"->\"$subissue\" $special\n" if ($self->{'allOpenIssues'}{$subissue});
            }
        }
    }
    return $gvContent;
}

sub new
{
    my ($class, @arguments) = @_;

    my $self = {};
    bless $self, $class;
    $self->parse_arguments(@arguments);

    return $self;
}

sub run
{
    my ($self) = @_;

    $columns = 50; # set wrap column for Text::Wrap

    my $jiraIssue = $self->{jiraIssue};
    my $gvContent = << 'EOM';
digraph "Jira issue graph" {
    rankdir=LR
    ranksep=.50
    nodesep=.10
    node [style=filled, fonttype=Helvetica, fontsize=8]
EOM
    my $currentDate = strftime("%Y-%m-%d %H:%M", localtime);
    $gvContent .= $self->fetchAllRelatedIssues($jiraIssue)
                . $self->calculateDependencies() . "\nlabel=\"Jira issue graph for "
                . "$jiraIssue @ $currentDate\"\ntooltip=\" \"\n}\n";

    print "Found $self->{'totalItems'} related items\n" if ($self->{verbose});
    #print $result;
    #print Dumper(\%issueLinks);

    open FILE, ">$jiraIssue.gv";
    print FILE $gvContent;
    close FILE;
}

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

Qt::Jira2Gv->new(@ARGV)->run if (!caller);
1;