#!/usr/bin/perl -wT
# -*- 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 Bugzilla Bug Tracking System.
#
# The Initial Developer of the Original Code is Netscape Communications
# Corporation. Portions created by Netscape are
# Copyright (C) 1998 Netscape Communications Corporation. All
# Rights Reserved.
#
# Contributor(s): Terry Weissman <terry@mozilla.org>
#                 Myk Melez <myk@mozilla.org>
#                 Daniel Raichle <draichle@gmx.net>
#                 Dave Miller <justdave@syndicomm.com>
#                 Alexander J. Vincent <ajvincent@juno.com>

################################################################################
# Script Initialization
################################################################################

# Make it harder for us to do dangerous things in Perl.
use strict;

use lib qw(.);

use vars qw(
  $template
  $vars
);

# Include the Bugzilla CGI and general utility library.
require "CGI.pl";

# Use these modules to handle flags.
use Bugzilla::Constants;
use Bugzilla::Flag; 
use Bugzilla::FlagType; 
use Bugzilla::User;
use Bugzilla::Util;

# Check whether or not the user is logged in and, if so, set the $::userid 
Bugzilla->login();

# The ID of the bug to which the attachment is attached.  Gets set
# by validateID() (which validates the attachment ID, not the bug ID, but has
# to check if the user is authorized to access this attachment) and is used 
# by Flag:: and FlagType::validate() to ensure the requestee (if any) for a 
# requested flag is authorized to see the bug in question.  Note: This should 
# really be defined just above validateID() itself, but it's used in the main 
# body of the script before that function is defined, so we define it up here 
# instead.  We should move the validation into each function and then move this
# to just above validateID().
my $bugid;

my $cgi = Bugzilla->cgi;

################################################################################
# Main Body Execution
################################################################################

# All calls to this script should contain an "action" variable whose value
# determines what the user wants to do.  The code below checks the value of
# that variable and runs the appropriate code.

# Determine whether to use the action specified by the user or the default.
my $action = $::FORM{'action'} || 'view';

if ($action eq "view")  
{ 
  validateID();
  view(); 
}
elsif ($action eq "interdiff")
{
  validateID('oldid');
  validateID('newid');
  validateFormat("html", "raw");
  validateContext();
  interdiff();
}
elsif ($action eq "diff")
{
  validateID();
  validateFormat("html", "raw");
  validateContext();
  diff();
}
elsif ($action eq "viewall") 
{ 
  ValidateBugID($::FORM{'bugid'});
  viewall(); 
}
elsif ($action eq "enter") 
{ 
  Bugzilla->login(LOGIN_REQUIRED);
  ValidateBugID($::FORM{'bugid'});
  validateCanChangeBug($::FORM{'bugid'});
  enter(); 
}
elsif ($action eq "insert")
{
  Bugzilla->login(LOGIN_REQUIRED);
  ValidateBugID($::FORM{'bugid'});
  validateCanChangeBug($::FORM{'bugid'});
  ValidateComment($::FORM{'comment'});
  validateFilename();
  validateIsPatch();
  my $data = validateData();
  validateDescription();
  validateContentType() unless $::FORM{'ispatch'};
  validateObsolete() if $::FORM{'obsolete'};
  insert($data);
}
elsif ($action eq "edit") 
{ 
  validateID();
  validateCanEdit($::FORM{'id'});
  edit(); 
}
elsif ($action eq "update") 
{ 
  Bugzilla->login(LOGIN_REQUIRED);
  ValidateComment($::FORM{'comment'});
  validateID();
  validateCanEdit($::FORM{'id'});
  validateCanChangeAttachment($::FORM{'id'});
  validateDescription();
  validateIsPatch();
  validateContentType() unless $::FORM{'ispatch'};
  validateIsObsolete();
  validatePrivate();
  
  # The order of these function calls is important, as both Flag::validate
  # and FlagType::validate assume User::match_field has ensured that the values
  # in the requestee fields are legitimate user email addresses.
  Bugzilla::User::match_field({ '^requestee(_type)?-(\d+)$' => 
                                    { 'type' => 'single' } });
  Bugzilla::Flag::validate(\%::FORM, $bugid);
  Bugzilla::FlagType::validate(\%::FORM, $bugid, $::FORM{'id'});
  
  update();
}
else 
{ 
  ThrowCodeError("unknown_action", { action => $action });
}

exit;

################################################################################
# Data Validation / Security Authorization
################################################################################

sub validateID
{
    my $param = @_ ? $_[0] : 'id';

    # Validate the value of the "id" form field, which must contain an
    # integer that is the ID of an existing attachment.

    $vars->{'attach_id'} = $::FORM{$param};
    
    detaint_natural($::FORM{$param}) 
     || ThrowUserError("invalid_attach_id");
  
    # Make sure the attachment exists in the database.
    SendSQL("SELECT bug_id, isprivate FROM attachments WHERE attach_id = $::FORM{$param}");
    MoreSQLData()
      || ThrowUserError("invalid_attach_id");

    # Make sure the user is authorized to access this attachment's bug.
    ($bugid, my $isprivate) = FetchSQLData();
    ValidateBugID($bugid);
    if (($isprivate > 0 ) && Param("insidergroup") && !(UserInGroup(Param("insidergroup")))) {
        ThrowUserError("attachment_access_denied");
    }
}

sub validateFormat
{
  $::FORM{'format'} ||= $_[0];
  if (! grep { $_ eq $::FORM{'format'} } @_)
  {
     $vars->{'format'} = $::FORM{'format'};
     $vars->{'formats'} = \@_;
     ThrowUserError("invalid_format");
  }
}

sub validateContext
{
  $::FORM{'context'} ||= "patch";
  if ($::FORM{'context'} ne "file" && $::FORM{'context'} ne "patch") {
    $vars->{'context'} = $::FORM{'context'};
    detaint_natural($::FORM{'context'})
      || ThrowUserError("invalid_context");
    delete $vars->{'context'};
  }
}

sub validateCanEdit
{
    my ($attach_id) = (@_);

    # If the user is not logged in, claim that they can edit. This allows
    # the edit screen to be displayed to people who aren't logged in.
    # People not logged in can't actually commit changes, because that code
    # calls Bugzilla->login with LOGIN_REQUIRED, not with LOGIN_NORMAL,
    # before calling this sub
    return if $::userid == 0;

    # People in editbugs can edit all attachments
    return if UserInGroup("editbugs");

    # Bug 97729 - the submitter can edit their attachments
    SendSQL("SELECT attach_id FROM attachments WHERE " .
            "attach_id = $attach_id AND submitter_id = $::userid");

    FetchSQLData()
      || ThrowUserError("illegal_attachment_edit",
                        { attach_id => $attach_id });
}

sub validateCanChangeAttachment 
{
    my ($attachid) = @_;
    SendSQL("SELECT product_id
             FROM attachments, bugs 
             WHERE attach_id = $attachid
             AND bugs.bug_id = attachments.bug_id");
    my $productid = FetchOneColumn();
    CanEditProductId($productid)
      || ThrowUserError("illegal_attachment_edit",
                        { attach_id => $attachid });
}

sub validateCanChangeBug
{
    my ($bugid) = @_;
    SendSQL("SELECT product_id
             FROM bugs 
             WHERE bug_id = $bugid");
    my $productid = FetchOneColumn();
    CanEditProductId($productid)
      || ThrowUserError("illegal_attachment_edit_bug",
                        { bug_id => $bugid });
}

sub validateDescription
{
  $::FORM{'description'}
    || ThrowUserError("missing_attachment_description");
}

sub validateIsPatch
{
  # Set the ispatch flag to zero if it is undefined, since the UI uses
  # an HTML checkbox to represent this flag, and unchecked HTML checkboxes
  # do not get sent in HTML requests.
  $::FORM{'ispatch'} = $::FORM{'ispatch'} ? 1 : 0;

  # Set the content type to text/plain if the attachment is a patch.
  $::FORM{'contenttype'} = "text/plain" if $::FORM{'ispatch'};
}

sub validateContentType
{
  if (!$::FORM{'contenttypemethod'})
  {
    ThrowUserError("missing_content_type_method");
  }
  elsif ($::FORM{'contenttypemethod'} eq 'autodetect')
  {
    my $contenttype = $cgi->uploadInfo($cgi->param('data'))->{'Content-Type'};
    # The user asked us to auto-detect the content type, so use the type
    # specified in the HTTP request headers.
    if ( !$contenttype )
    {
      ThrowUserError("missing_content_type");
    }
    $::FORM{'contenttype'} = $contenttype;
  }
  elsif ($::FORM{'contenttypemethod'} eq 'list')
  {
    # The user selected a content type from the list, so use their selection.
    $::FORM{'contenttype'} = $::FORM{'contenttypeselection'};
  }
  elsif ($::FORM{'contenttypemethod'} eq 'manual')
  {
    # The user entered a content type manually, so use their entry.
    $::FORM{'contenttype'} = $::FORM{'contenttypeentry'};
  }
  else
  {
    ThrowCodeError("illegal_content_type_method",
                   { contenttypemethod => $::FORM{'contenttypemethod'} });
  }

  if ( $::FORM{'contenttype'} !~ /^(application|audio|image|message|model|multipart|text|video)\/.+$/ )
  {
    ThrowUserError("invalid_content_type",
                   { contenttype => $::FORM{'contenttype'} });
  }
}

sub validateIsObsolete
{
  # Set the isobsolete flag to zero if it is undefined, since the UI uses
  # an HTML checkbox to represent this flag, and unchecked HTML checkboxes
  # do not get sent in HTML requests.
  $::FORM{'isobsolete'} = $::FORM{'isobsolete'} ? 1 : 0;
}

sub validatePrivate
{
    # Set the isprivate flag to zero if it is undefined, since the UI uses
    # an HTML checkbox to represent this flag, and unchecked HTML checkboxes
    # do not get sent in HTML requests.
    $::FORM{'isprivate'} = $::FORM{'isprivate'} ? 1 : 0;
}

sub validateData
{
  my $maxsize = $::FORM{'ispatch'} ? Param('maxpatchsize') : Param('maxattachmentsize');
  $maxsize *= 1024; # Convert from K

  my $fh = $cgi->upload('data');
  my $data;

  # We could get away with reading only as much as required, except that then
  # we wouldn't have a size to print to the error handler below.
  {
      # enable 'slurp' mode
      local $/;
      $data = <$fh>;
  }

  $data
    || ThrowUserError("zero_length_file");

  # Make sure the attachment does not exceed the maximum permitted size
  my $len = length($data);
  if ($maxsize && $len > $maxsize) {
      my $vars = { filesize => sprintf("%.0f", $len/1024) };
      if ( $::FORM{'ispatch'} ) {
          ThrowUserError("patch_too_large", $vars);
      } else {
          ThrowUserError("file_too_large", $vars);
      }
  }

  return $data;
}

my $filename;
sub validateFilename
{
  defined $cgi->upload('data')
    || ThrowUserError("file_not_specified");

  $filename = $cgi->upload('data');
  
  # Remove path info (if any) from the file name.  The browser should do this
  # for us, but some are buggy.  This may not work on Mac file names and could
  # mess up file names with slashes in them, but them's the breaks.  We only
  # use this as a hint to users downloading attachments anyway, so it's not 
  # a big deal if it munges incorrectly occasionally.
  $filename =~ s/^.*[\/\\]//;

  # Truncate the filename to 100 characters, counting from the end of the string
  # to make sure we keep the filename extension.
  $filename = substr($filename, -100, 100);
}

sub validateObsolete
{
  # Make sure the attachment id is valid and the user has permissions to view
  # the bug to which it is attached.
  foreach my $attachid (@{$::MFORM{'obsolete'}}) {
    my $vars = {};
    $vars->{'attach_id'} = $attachid;
    
    detaint_natural($attachid)
      || ThrowCodeError("invalid_attach_id_to_obsolete", $vars);
  
    SendSQL("SELECT bug_id, isobsolete, description 
             FROM attachments WHERE attach_id = $attachid");

    # Make sure the attachment exists in the database.
    MoreSQLData()
      || ThrowUserError("invalid_attach_id", $vars);

    my ($bugid, $isobsolete, $description) = FetchSQLData();

    $vars->{'description'} = $description;
    
    if ($bugid != $::FORM{'bugid'})
    {
      $vars->{'my_bug_id'} = $::FORM{'bugid'};
      $vars->{'attach_bug_id'} = $bugid;
      ThrowCodeError("mismatched_bug_ids_on_obsolete", $vars);
    }

    if ( $isobsolete )
    {
      ThrowCodeError("attachment_already_obsolete", $vars);
    }

    # Check that the user can modify this attachment
    validateCanEdit($attachid);
  }
}

# Returns 1 if the parameter is a content-type viewable in this browser
# Note that we don't use $cgi->Accept()'s ability to check if a content-type
# matches, because this will return a value even if it's matched by the generic
# */* which most browsers add to the end of their Accept: headers.
sub isViewable
{
  my $contenttype = trim(shift);
    
  # We assume we can view all text and image types  
  if ($contenttype =~ /^(text|image)\//) {
    return 1;
  }
  
  # Mozilla can view XUL. Note the trailing slash on the Gecko detection to
  # avoid sending XUL to Safari.
  if (($contenttype =~ /^application\/vnd\.mozilla\./) &&
      ($cgi->user_agent() =~ /Gecko\//))
  {
    return 1;
  }

  # If it's not one of the above types, we check the Accept: header for any 
  # types mentioned explicitly.
  my $accept = join(",", $cgi->Accept());
  
  if ($accept =~ /^(.*,)?\Q$contenttype\E(,.*)?$/) {
    return 1;
  }
  
  return 0;
}

################################################################################
# Functions
################################################################################

sub view
{
    # Display an attachment.

    # Retrieve the attachment content and its content type from the database.
    SendSQL("SELECT mimetype, filename, thedata FROM attachments WHERE attach_id = $::FORM{'id'}");
    my ($contenttype, $filename, $thedata) = FetchSQLData();
   
    # Bug 111522: allow overriding content-type manually in the posted $::FORM.
    if ($::FORM{'content_type'})
    {
        $::FORM{'contenttypemethod'} = 'manual';
        $::FORM{'contenttypeentry'} = $::FORM{'content_type'};
        validateContentType();
        $contenttype = $::FORM{'content_type'};
    }

    # Return the appropriate HTTP response headers.
    $filename =~ s/^.*[\/\\]//;
    my $filesize = length($thedata);

    # escape quotes and backslashes in the filename, per RFCs 2045/822
    $filename =~ s/\\/\\\\/g; # escape backslashes
    $filename =~ s/"/\\"/g; # escape quotes

    print Bugzilla->cgi->header(-type=>"$contenttype; name=\"$filename\"",
                                -content_disposition=> "inline; filename=\"$filename\"",
                                -content_length => $filesize);

    print $thedata;
}

sub interdiff
{
  # Get old patch data
  my ($old_bugid, $old_description, $old_filename, $old_file_list) =
      get_unified_diff($::FORM{'oldid'});

  # Get new patch data
  my ($new_bugid, $new_description, $new_filename, $new_file_list) =
      get_unified_diff($::FORM{'newid'});

  my $warning = warn_if_interdiff_might_fail($old_file_list, $new_file_list);

  #
  # send through interdiff, send output directly to template
  #
  # Must hack path so that interdiff will work.
  #
  $ENV{'PATH'} = $::diffpath;
  open my $interdiff_fh, "$::interdiffbin $old_filename $new_filename|";
  binmode $interdiff_fh;
  my ($reader, $last_reader) = setup_patch_readers("");
  if ($::FORM{'format'} eq "raw")
  {
    require PatchReader::DiffPrinter::raw;
    $last_reader->sends_data_to(new PatchReader::DiffPrinter::raw());
    # Actually print out the patch
    print $cgi->header(-type => 'text/plain',
                       -expires => '+3M');
  }
  else
  {
    $vars->{warning} = $warning if $warning;
    $vars->{bugid} = $new_bugid;
    $vars->{oldid} = $::FORM{'oldid'};
    $vars->{old_desc} = $old_description;
    $vars->{newid} = $::FORM{'newid'};
    $vars->{new_desc} = $new_description;
    delete $vars->{attachid};
    delete $vars->{do_context};
    delete $vars->{context};
    setup_template_patch_reader($last_reader);
  }
  $reader->iterate_fh($interdiff_fh, "interdiff #$::FORM{'oldid'} #$::FORM{'newid'}");
  close $interdiff_fh;
  $ENV{'PATH'} = '';

  #
  # Delete temporary files
  #
  unlink($old_filename) or warn "Could not unlink $old_filename: $!";
  unlink($new_filename) or warn "Could not unlink $new_filename: $!";
}

sub get_unified_diff
{
  my ($id) = @_;

  # Bring in the modules we need
  require PatchReader::Raw;
  require PatchReader::FixPatchRoot;
  require PatchReader::DiffPrinter::raw;
  require PatchReader::PatchInfoGrabber;
  require File::Temp;

  # Get the patch
  SendSQL("SELECT bug_id, description, ispatch, thedata FROM attachments WHERE attach_id = $id");
  my ($bugid, $description, $ispatch, $thedata) = FetchSQLData();
  if (!$ispatch) {
    $vars->{'attach_id'} = $id;
    ThrowCodeError("must_be_patch");
  }

  # Reads in the patch, converting to unified diff in a temp file
  my $reader = new PatchReader::Raw;
  my $last_reader = $reader;

  # fixes patch root (makes canonical if possible)
  if (Param('cvsroot')) {
    my $fix_patch_root = new PatchReader::FixPatchRoot(Param('cvsroot'));
    $last_reader->sends_data_to($fix_patch_root);
    $last_reader = $fix_patch_root;
  }

  # Grabs the patch file info
  my $patch_info_grabber = new PatchReader::PatchInfoGrabber();
  $last_reader->sends_data_to($patch_info_grabber);
  $last_reader = $patch_info_grabber;

  # Prints out to temporary file
  my ($fh, $filename) = File::Temp::tempfile();
  my $raw_printer = new PatchReader::DiffPrinter::raw($fh);
  $last_reader->sends_data_to($raw_printer);
  $last_reader = $raw_printer;

  # Iterate!
  $reader->iterate_string($id, $thedata);

  return ($bugid, $description, $filename, $patch_info_grabber->patch_info()->{files});
}

sub warn_if_interdiff_might_fail {
  my ($old_file_list, $new_file_list) = @_;
  # Verify that the list of files diffed is the same
  my @old_files = sort keys %{$old_file_list};
  my @new_files = sort keys %{$new_file_list};
  if (@old_files != @new_files ||
      join(' ', @old_files) ne join(' ', @new_files)) {
    return "interdiff1";
  }

  # Verify that the revisions in the files are the same
  foreach my $file (keys %{$old_file_list}) {
    if ($old_file_list->{$file}{old_revision} ne
        $new_file_list->{$file}{old_revision}) {
      return "interdiff2";
    }
  }

  return undef;
}

sub setup_patch_readers {
  my ($diff_root) = @_;

  #
  # Parameters:
  # format=raw|html
  # context=patch|file|0-n
  # collapsed=0|1
  # headers=0|1
  #

  # Define the patch readers
  # The reader that reads the patch in (whatever its format)
  require PatchReader::Raw;
  my $reader = new PatchReader::Raw;
  my $last_reader = $reader;
  # Fix the patch root if we have a cvs root
  if (Param('cvsroot'))
  {
    require PatchReader::FixPatchRoot;
    $last_reader->sends_data_to(new PatchReader::FixPatchRoot(Param('cvsroot')));
    $last_reader->sends_data_to->diff_root($diff_root) if defined($diff_root);
    $last_reader = $last_reader->sends_data_to;
  }
  # Add in cvs context if we have the necessary info to do it
  if ($::FORM{'context'} ne "patch" && $::cvsbin && Param('cvsroot_get'))
  {
    require PatchReader::AddCVSContext;
    $last_reader->sends_data_to(
        new PatchReader::AddCVSContext($::FORM{'context'},
                                         Param('cvsroot_get')));
    $last_reader = $last_reader->sends_data_to;
  }
  return ($reader, $last_reader);
}

sub setup_template_patch_reader
{
  my ($last_reader) = @_;

  require PatchReader::DiffPrinter::template;

  my $format = $::FORM{'format'};

  # Define the vars for templates
  if (defined($::FORM{'headers'})) {
    $vars->{headers} = $::FORM{'headers'};
  } else {
    $vars->{headers} = 1 if !defined($::FORM{'headers'});
  }
  $vars->{collapsed} = $::FORM{'collapsed'};
  $vars->{context} = $::FORM{'context'};
  $vars->{do_context} = $::cvsbin && Param('cvsroot_get') && !$vars->{'newid'};

  # Print everything out
  print $cgi->header(-type => 'text/html',
                     -expires => '+3M');
  $last_reader->sends_data_to(new PatchReader::DiffPrinter::template($template,
                             "attachment/diff-header.$format.tmpl",
                             "attachment/diff-file.$format.tmpl",
                             "attachment/diff-footer.$format.tmpl",
                             { %{$vars},
                               bonsai_url => Param('bonsai_url'),
                               lxr_url => Param('lxr_url'),
                               lxr_root => Param('lxr_root'),
                             }));
}

sub diff
{
  # Get patch data
  SendSQL("SELECT bug_id, description, ispatch, thedata FROM attachments WHERE attach_id = $::FORM{'id'}");
  my ($bugid, $description, $ispatch, $thedata) = FetchSQLData();

  # If it is not a patch, view normally
  if (!$ispatch)
  {
    view();
    return;
  }

  my ($reader, $last_reader) = setup_patch_readers();

  if ($::FORM{'format'} eq "raw")
  {
    require PatchReader::DiffPrinter::raw;
    $last_reader->sends_data_to(new PatchReader::DiffPrinter::raw());
    # Actually print out the patch
    use vars qw($cgi);
    print $cgi->header(-type => 'text/plain',
                       -expires => '+3M');
    $reader->iterate_string("Attachment " . $::FORM{'id'}, $thedata);
  }
  else
  {
    $vars->{other_patches} = [];
    if ($::interdiffbin && $::diffpath) {
      # Get list of attachments on this bug.
      # Ignore the current patch, but select the one right before it
      # chronologically.
      SendSQL("SELECT attach_id, description FROM attachments WHERE bug_id = $bugid AND ispatch = 1 ORDER BY creation_ts DESC");
      my $select_next_patch = 0;
      while (my ($other_id, $other_desc) = FetchSQLData()) {
        if ($other_id eq $::FORM{'id'}) {
          $select_next_patch = 1;
        } else {
          push @{$vars->{other_patches}}, { id => $other_id, desc => $other_desc, selected => $select_next_patch };
          if ($select_next_patch) {
            $select_next_patch = 0;
          }
        }
      }
    }

    $vars->{bugid} = $bugid;
    $vars->{attachid} = $::FORM{'id'};
    $vars->{description} = $description;
    setup_template_patch_reader($last_reader);
    # Actually print out the patch
    $reader->iterate_string("Attachment " . $::FORM{'id'}, $thedata);
  }
}

sub viewall
{
  # Display all attachments for a given bug in a series of IFRAMEs within one HTML page.

  # Retrieve the attachments from the database and write them into an array
  # of hashes where each hash represents one attachment.
    my $privacy = "";
    if (Param("insidergroup") && !(UserInGroup(Param("insidergroup")))) {
        $privacy = "AND isprivate < 1 ";
    }
    SendSQL("SELECT attach_id, DATE_FORMAT(creation_ts, '%Y.%m.%d %H:%i'),
            mimetype, description, ispatch, isobsolete, isprivate, 
            LENGTH(thedata)
            FROM attachments WHERE bug_id = $::FORM{'bugid'} $privacy 
            ORDER BY attach_id");
  my @attachments; # the attachments array
  while (MoreSQLData())
  {
    my %a; # the attachment hash
    ($a{'attachid'}, $a{'date'}, $a{'contenttype'}, 
     $a{'description'}, $a{'ispatch'}, $a{'isobsolete'}, $a{'isprivate'},
     $a{'datasize'}) = FetchSQLData();
    $a{'isviewable'} = isViewable($a{'contenttype'});

    # Add the hash representing the attachment to the array of attachments.
    push @attachments, \%a;
  }

  # Retrieve the bug summary (for displaying on screen) and assignee.
  SendSQL("SELECT short_desc, assigned_to FROM bugs " .
          "WHERE bug_id = $::FORM{'bugid'}");
  my ($bugsummary, $assignee_id) = FetchSQLData();

  # Define the variables and functions that will be passed to the UI template.
  $vars->{'bugid'} = $::FORM{'bugid'};
  $vars->{'attachments'} = \@attachments;
  $vars->{'bugassignee_id'} = $assignee_id;
  $vars->{'bugsummary'} = $bugsummary;
  $vars->{'GetBugLink'} = \&GetBugLink;

  print Bugzilla->cgi->header();

  # Generate and return the UI (HTML page) from the appropriate template.
  $template->process("attachment/show-multiple.html.tmpl", $vars)
    || ThrowTemplateError($template->error());
}


sub enter
{
  # Display a form for entering a new attachment.

  # Retrieve the attachments the user can edit from the database and write
  # them into an array of hashes where each hash represents one attachment.
  my $canEdit = "";
  if (!UserInGroup("editbugs")) {
      $canEdit = "AND submitter_id = $::userid";
  }
  SendSQL("SELECT attach_id, description, isprivate
           FROM attachments
           WHERE bug_id = $::FORM{'bugid'}
           AND isobsolete = 0 $canEdit
           ORDER BY attach_id");
  my @attachments; # the attachments array
  while ( MoreSQLData() ) {
    my %a; # the attachment hash
    ($a{'id'}, $a{'description'}, $a{'isprivate'}) = FetchSQLData();

    # Add the hash representing the attachment to the array of attachments.
    push @attachments, \%a;
  }

  # Retrieve the bug summary (for displaying on screen) and assignee.
  SendSQL("SELECT short_desc, assigned_to FROM bugs 
           WHERE bug_id = $::FORM{'bugid'}");
  my ($bugsummary, $assignee_id) = FetchSQLData();

  # Define the variables and functions that will be passed to the UI template.
  $vars->{'bugid'} = $::FORM{'bugid'};
  $vars->{'attachments'} = \@attachments;
  $vars->{'bugassignee_id'} = $assignee_id;
  $vars->{'bugsummary'} = $bugsummary;
  $vars->{'GetBugLink'} = \&GetBugLink;

  print Bugzilla->cgi->header();

  # Generate and return the UI (HTML page) from the appropriate template.
  $template->process("attachment/create.html.tmpl", $vars)
    || ThrowTemplateError($template->error());
}


sub insert
{
  my ($data) = @_;

  # Insert a new attachment into the database.

  # Escape characters in strings that will be used in SQL statements.
  $filename = SqlQuote($filename);
  my $description = SqlQuote($::FORM{'description'});
  my $contenttype = SqlQuote($::FORM{'contenttype'});
  my $thedata = SqlQuote($data);
  my $isprivate = $::FORM{'isprivate'} ? 1 : 0;

  # Insert the attachment into the database.
  SendSQL("INSERT INTO attachments (bug_id, creation_ts, filename, description, mimetype, ispatch, isprivate, submitter_id, thedata) 
           VALUES ($::FORM{'bugid'}, now(), $filename, $description, $contenttype, $::FORM{'ispatch'}, $isprivate, $::userid, $thedata)");

  # Retrieve the ID of the newly created attachment record.
  SendSQL("SELECT LAST_INSERT_ID()");
  my $attachid = FetchOneColumn();

  # Insert a comment about the new attachment into the database.
  my $comment = "Created an attachment (id=$attachid)\n$::FORM{'description'}\n";
  $comment .= ("\n" . $::FORM{'comment'}) if $::FORM{'comment'};

  use Text::Wrap;
  $Text::Wrap::columns = 80;
  $Text::Wrap::huge = 'overflow';
  $comment = Text::Wrap::wrap('', '', $comment);

  AppendComment($::FORM{'bugid'}, 
                $::COOKIE{"Bugzilla_login"},
                $comment,
                $isprivate);

  # Make existing attachments obsolete.
  my $fieldid = GetFieldID('attachments.isobsolete');
  foreach my $obsolete_id (@{$::MFORM{'obsolete'}}) {
      SendSQL("UPDATE attachments SET isobsolete = 1 WHERE attach_id = $obsolete_id");
      SendSQL("INSERT INTO bugs_activity (bug_id, attach_id, who, bug_when, fieldid, removed, added) 
               VALUES ($::FORM{'bugid'}, $obsolete_id, $::userid, NOW(), $fieldid, '0', '1')");
      # If the obsolete attachment has pending flags, migrate them to the new attachment.
      if (Bugzilla::Flag::count({ 'attach_id' => $obsolete_id , 'status' => 'pending' })) {
        Bugzilla::Flag::migrate($obsolete_id, $attachid);
      }
  }

  # Assign the bug to the user, if they are allowed to take it
  my $forcecc = "";
  
  if ($::FORM{'takebug'} && UserInGroup("editbugs")) {
      SendSQL("select NOW()");
      my $timestamp = FetchOneColumn();
      
      my @fields = ("assigned_to", "bug_status", "resolution", "login_name");
      
      # Get the old values, for the bugs_activity table
      SendSQL("SELECT " . join(", ", @fields) . " FROM bugs, profiles " .
              "WHERE bugs.bug_id = $::FORM{'bugid'} " .
              "AND   profiles.userid = bugs.assigned_to");
      
      my @oldvalues = FetchSQLData();
      my @newvalues = ($::userid, "ASSIGNED", "", DBID_to_name($::userid));
      
      # Make sure the person we are taking the bug from gets mail.
      $forcecc = $oldvalues[3];  
                  
      @oldvalues = map(SqlQuote($_), @oldvalues);
      @newvalues = map(SqlQuote($_), @newvalues);
               
      # Update the bug record. Note that this doesn't involve login_name.
      SendSQL("UPDATE bugs SET " . 
              join(", ", map("$fields[$_] = $newvalues[$_]", (0..2))) . 
              " WHERE bug_id = $::FORM{'bugid'}");
      
      # We store email addresses in the bugs_activity table rather than IDs.
      $oldvalues[0] = $oldvalues[3];
      $newvalues[0] = $newvalues[3];
      
      # Add the changes to the bugs_activity table
      for (my $i = 0; $i < 3; $i++) {
          if ($oldvalues[$i] ne $newvalues[$i]) {
              my $fieldid = GetFieldID($fields[$i]);
              SendSQL("INSERT INTO bugs_activity " .
                      "(bug_id, who, bug_when, fieldid, removed, added) " .
                      " VALUES ($::FORM{'bugid'}, $::userid, " . 
                      SqlQuote($timestamp) . 
                      ", $fieldid, $oldvalues[$i], $newvalues[$i])");
          }
      }      
  }   
  
  # Define the variables and functions that will be passed to the UI template.
  $vars->{'mailrecipients'} =  { 'changer' => $::COOKIE{'Bugzilla_login'} };
  $vars->{'bugid'} = $::FORM{'bugid'};
  $vars->{'attachid'} = $attachid;
  $vars->{'description'} = $description;
  $vars->{'contenttypemethod'} = $::FORM{'contenttypemethod'};
  $vars->{'contenttype'} = $::FORM{'contenttype'};

  print Bugzilla->cgi->header();

  # Generate and return the UI (HTML page) from the appropriate template.
  $template->process("attachment/created.html.tmpl", $vars)
    || ThrowTemplateError($template->error());
}


sub edit
{
  # Edit an attachment record.  Users with "editbugs" privileges, (or the 
  # original attachment's submitter) can edit the attachment's description,
  # content type, ispatch and isobsolete flags, and statuses, and they can
  # also submit a comment that appears in the bug.
  # Users cannot edit the content of the attachment itself.

  # Retrieve the attachment from the database.
  SendSQL("SELECT description, mimetype, filename, bug_id, ispatch, isobsolete, isprivate, LENGTH(thedata)
           FROM attachments WHERE attach_id = $::FORM{'id'}");
  my ($description, $contenttype, $filename, $bugid, $ispatch, $isobsolete, $isprivate, $datasize) = FetchSQLData();

  my $isviewable = isViewable($contenttype);

  # Retrieve a list of attachments for this bug as well as a summary of the bug
  # to use in a navigation bar across the top of the screen.
  SendSQL("SELECT attach_id FROM attachments WHERE bug_id = $bugid ORDER BY attach_id");
  my @bugattachments;
  push(@bugattachments, FetchSQLData()) while (MoreSQLData());
  SendSQL("SELECT short_desc FROM bugs WHERE bug_id = $bugid");
  my ($bugsummary) = FetchSQLData();
  
  # Get a list of flag types that can be set for this attachment.
  SendSQL("SELECT product_id, component_id FROM bugs WHERE bug_id = $bugid");
  my ($product_id, $component_id) = FetchSQLData();
  my $flag_types = Bugzilla::FlagType::match({ 'target_type'  => 'attachment' , 
                                               'product_id'   => $product_id , 
                                               'component_id' => $component_id });
  foreach my $flag_type (@$flag_types) {
    $flag_type->{'flags'} = Bugzilla::Flag::match({ 'type_id'   => $flag_type->{'id'}, 
                                                    'attach_id' => $::FORM{'id'} });
  }
  $vars->{'flag_types'} = $flag_types;
  $vars->{'any_flags_requesteeble'} = grep($_->{'is_requesteeble'}, @$flag_types);
  
  # Define the variables and functions that will be passed to the UI template.
  $vars->{'attachid'} = $::FORM{'id'}; 
  $vars->{'description'} = $description; 
  $vars->{'contenttype'} = $contenttype; 
  $vars->{'filename'} = $filename;
  $vars->{'bugid'} = $bugid; 
  $vars->{'bugsummary'} = $bugsummary; 
  $vars->{'ispatch'} = $ispatch; 
  $vars->{'isobsolete'} = $isobsolete; 
  $vars->{'isprivate'} = $isprivate; 
  $vars->{'datasize'} = $datasize;
  $vars->{'isviewable'} = $isviewable; 
  $vars->{'attachments'} = \@bugattachments; 
  $vars->{'GetBugLink'} = \&GetBugLink;

  # Determine if PatchReader is installed
  eval {
    require PatchReader;
    $vars->{'patchviewerinstalled'} = 1;
  };
  print Bugzilla->cgi->header();

  # Generate and return the UI (HTML page) from the appropriate template.
  $template->process("attachment/edit.html.tmpl", $vars)
    || ThrowTemplateError($template->error());
}


sub update
{
  # Updates an attachment record.

  # Get the bug ID for the bug to which this attachment is attached.
  SendSQL("SELECT bug_id FROM attachments WHERE attach_id = $::FORM{'id'}");
  my $bugid = FetchSQLData();
  unless ($bugid) 
  {
    ThrowUserError("invalid_bug_id",
                   { bug_id => $bugid });
  }
  
  # Lock database tables in preparation for updating the attachment.
  SendSQL("LOCK TABLES attachments WRITE , flags WRITE , " . 
          "flagtypes READ , fielddefs READ , bugs_activity WRITE, " . 
          "flaginclusions AS i READ, flagexclusions AS e READ, " . 
          # cc, bug_group_map, user_group_map, and groups are in here so we
          # can check the permissions of flag requestees and email addresses
          # on the flag type cc: lists via the CanSeeBug
          # function call in Flag::notify. group_group_map is in here in case
          # Bugzilla::User needs to rederive groups. profiles and 
          # user_group_map would be READ locks instead of WRITE locks if it
          # weren't for derive_groups, which needs to write to those tables.
          "bugs READ, profiles WRITE, " . 
          "cc READ, bug_group_map READ, user_group_map WRITE, " . 
          "group_group_map READ, groups READ");
  
  # Get a copy of the attachment record before we make changes
  # so we can record those changes in the activity table.
  SendSQL("SELECT description, mimetype, filename, ispatch, isobsolete, isprivate
           FROM attachments WHERE attach_id = $::FORM{'id'}");
  my ($olddescription, $oldcontenttype, $oldfilename, $oldispatch,
      $oldisobsolete, $oldisprivate) = FetchSQLData();

  # Quote the description and content type for use in the SQL UPDATE statement.
  my $quoteddescription = SqlQuote($::FORM{'description'});
  my $quotedcontenttype = SqlQuote($::FORM{'contenttype'});
  my $quotedfilename = SqlQuote($::FORM{'filename'});

  # Update the attachment record in the database.
  # Sets the creation timestamp to itself to avoid it being updated automatically.
  SendSQL("UPDATE  attachments 
           SET     description = $quoteddescription , 
                   mimetype = $quotedcontenttype , 
                   filename = $quotedfilename ,
                   ispatch = $::FORM{'ispatch'} , 
                   isobsolete = $::FORM{'isobsolete'} ,
                   isprivate = $::FORM{'isprivate'} 
           WHERE   attach_id = $::FORM{'id'}
         ");

  # Figure out when the changes were made.
  SendSQL("SELECT NOW()");
  my $timestamp = FetchOneColumn();
    
  # Record changes in the activity table.
  my $sql_timestamp = SqlQuote($timestamp);
  if ($olddescription ne $::FORM{'description'}) {
    my $quotedolddescription = SqlQuote($olddescription);
    my $fieldid = GetFieldID('attachments.description');
    SendSQL("INSERT INTO bugs_activity (bug_id, attach_id, who, bug_when, fieldid, removed, added) 
             VALUES ($bugid, $::FORM{'id'}, $::userid, $sql_timestamp, $fieldid, $quotedolddescription, $quoteddescription)");
  }
  if ($oldcontenttype ne $::FORM{'contenttype'}) {
    my $quotedoldcontenttype = SqlQuote($oldcontenttype);
    my $fieldid = GetFieldID('attachments.mimetype');
    SendSQL("INSERT INTO bugs_activity (bug_id, attach_id, who, bug_when, fieldid, removed, added) 
             VALUES ($bugid, $::FORM{'id'}, $::userid, $sql_timestamp, $fieldid, $quotedoldcontenttype, $quotedcontenttype)");
  }
  if ($oldfilename ne $::FORM{'filename'}) {
    my $quotedoldfilename = SqlQuote($oldfilename);
    my $fieldid = GetFieldID('attachments.filename');
    SendSQL("INSERT INTO bugs_activity (bug_id, attach_id, who, bug_when, fieldid, removed, added) 
             VALUES ($bugid, $::FORM{'id'}, $::userid, NOW(), $fieldid, $quotedoldfilename, $quotedfilename)");
  }
  if ($oldispatch ne $::FORM{'ispatch'}) {
    my $fieldid = GetFieldID('attachments.ispatch');
    SendSQL("INSERT INTO bugs_activity (bug_id, attach_id, who, bug_when, fieldid, removed, added) 
             VALUES ($bugid, $::FORM{'id'}, $::userid, $sql_timestamp, $fieldid, $oldispatch, $::FORM{'ispatch'})");
  }
  if ($oldisobsolete ne $::FORM{'isobsolete'}) {
    my $fieldid = GetFieldID('attachments.isobsolete');
    SendSQL("INSERT INTO bugs_activity (bug_id, attach_id, who, bug_when, fieldid, removed, added) 
             VALUES ($bugid, $::FORM{'id'}, $::userid, $sql_timestamp, $fieldid, $oldisobsolete, $::FORM{'isobsolete'})");
  }
  if ($oldisprivate ne $::FORM{'isprivate'}) {
    my $fieldid = GetFieldID('attachments.isprivate');
    SendSQL("INSERT INTO bugs_activity (bug_id, attach_id, who, bug_when, fieldid, removed, added) 
             VALUES ($bugid, $::FORM{'id'}, $::userid, NOW(), $fieldid, $oldisprivate, $::FORM{'isprivate'})");
  }
  
  # Update flags.
  my $target = Bugzilla::Flag::GetTarget(undef, $::FORM{'id'});
  Bugzilla::Flag::process($target, $timestamp, \%::FORM);
  
  # Unlock all database tables now that we are finished updating the database.
  SendSQL("UNLOCK TABLES");

  # If the user submitted a comment while editing the attachment, 
  # add the comment to the bug.
  if ( $::FORM{'comment'} )
  {
    use Text::Wrap;
    $Text::Wrap::columns = 80;
    $Text::Wrap::huge = 'wrap';

    # Append a string to the comment to let users know that the comment came from
    # the "edit attachment" screen.
    my $comment = qq|(From update of attachment $::FORM{'id'})\n| . $::FORM{'comment'};

    my $wrappedcomment = "";
    foreach my $line (split(/\r\n|\r|\n/, $comment))
    {
      if ( $line =~ /^>/ )
      {
        $wrappedcomment .= $line . "\n";
      }
      else
      {
        $wrappedcomment .= wrap('', '', $line) . "\n";
      }
    }

    # Get the user's login name since the AppendComment function needs it.
    my $who = DBID_to_name($::userid);
    # Mention $::userid again so Perl doesn't give me a warning about it.
    my $neverused = $::userid;

    # Append the comment to the list of comments in the database.
    AppendComment($bugid, $who, $wrappedcomment, $::FORM{'isprivate'}, $timestamp);

  }
  
  # Define the variables and functions that will be passed to the UI template.
  $vars->{'mailrecipients'} = { 'changer' => $::COOKIE{'Bugzilla_login'} };
  $vars->{'attachid'} = $::FORM{'id'}; 
  $vars->{'bugid'} = $bugid; 

  print Bugzilla->cgi->header();

  # Generate and return the UI (HTML page) from the appropriate template.
  $template->process("attachment/updated.html.tmpl", $vars)
    || ThrowTemplateError($template->error());
}