# -*- Mode: perl; indent-tabs-mode: nil -*-
#
# The contents of this file are subject to the Mozilla Public
# License Version 1.1 (the "License"); you may not use this file
# except in compliance with the License. You may obtain a copy of
# the License at http://www.mozilla.org/MPL/
#
# Software distributed under the License is distributed on an "AS
# IS" basis, WITHOUT WARRANTY OF ANY KIND, either express or
# implied. See the License for the specific language governing
# rights and limitations under the License.
#
# The Original Code is the TypeSniffer Bugzilla Extension.
#
# The Initial Developer of the Original Code is The Mozilla Foundation.
# Portions created by the Initial Developer are Copyright (C) 2010 the
# Initial Developer. All Rights Reserved.
#
# Contributor(s):
#   Gervase Markham <gerv@mozilla.org>

package Bugzilla::Extension::TypeSniffer;

use 5.10.1;
use strict;
use warnings;

use base qw(Bugzilla::Extension);

use File::MimeInfo::Magic;
use IO::Scalar;

our $VERSION = '1';

# These extensions override/supplement File::MimeInfo::Magic's detection.
our %EXTENSION_OVERRIDES = (
    '.lang' => 'text/plain',
);

################################################################################
# This extension uses magic to guess MIME types for data where the browser has
# told us it's application/octet-stream (probably because there's no file
# extension, or it's a text type with a non-.txt file extension).
################################################################################
sub attachment_process_data {
    my ($self, $args) = @_;
    my $attributes = $args->{'attributes'};
    my $params = Bugzilla->input_params;

    # If we have autodetected application/octet-stream from the Content-Type
    # header, let's have a better go using a sniffer.
    if ($params->{'contenttypemethod'} &&
        $params->{'contenttypemethod'} eq 'autodetect' &&
        $attributes->{'mimetype'} eq 'application/octet-stream')
    {
        my $filename = $attributes->{'filename'} . '';

        # Check for an override first
        if ($filename =~ /^.+(\..+$)/) {
            my $ext = lc($1);
            if (exists $EXTENSION_OVERRIDES{$ext}) {
                $attributes->{'mimetype'} = $EXTENSION_OVERRIDES{$ext};
                return;
            }
        }

        # Then try file extension detection
        my $mimetype = mimetype($filename);
        if ($mimetype) {
            $attributes->{'mimetype'} = $mimetype;
            return;
        }

        # data attribute can be either scalar data or filehandle
        # bugzilla.org/docs/3.6/en/html/api/Bugzilla/Attachment.html#create
        my $fh = $attributes->{'data'};
        if (!ref($fh)) {
            my $data = $attributes->{'data'};
            $fh = new IO::Scalar \$data;
        }
        else {
            # CGI.pm sends us an Fh that isn't actually an IO::Handle, but
            # has a method for getting an actual handle out of it.
            if (!$fh->isa('IO::Handle')) {
                $fh = $fh->handle;
                # ->handle returns an literal IO::Handle, even though the
                # underlying object is a file. So we rebless it to be a proper
                # IO::File object so that we can call ->seek on it and so on.
                # Just in case CGI.pm fixes this some day, we check ->isa first.
                if (!$fh->isa('IO::File')) {
                    bless $fh, 'IO::File';
                }
            }
        }

        $mimetype = mimetype($fh);
        $fh->seek(0, 0);
        if ($mimetype) {
            $attributes->{'mimetype'} = $mimetype;
        }
    }
}

__PACKAGE__->NAME;