# Copyright (C) 2004 Brock Wilcox <awwaiid@thelackthereof.org>

# Copyright (C) 2004 Brock Wilcox <[email protected]>
# Copyright (C) 2006, 2007 Alex Schroeder <[email protected]>
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 3 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program. If not, see <http://www.gnu.org/licenses/>.

$ModulesDescription .= '<p><a href="http://git.savannah.gnu.org/cgit/oddmuse.git/tree/modules/questionasker.pl">questionasker.pl</a>, see <a href="http://www.oddmuse.org/cgi-bin/oddmuse/QuestionAsker_Extension">QuestionAsker Extension</a></p>';

use vars qw(@QuestionaskerQuestions
$QuestionaskerRememberAnswer
$QuestionaskerSecretKey
$QuestionaskerRequiredList
%QuestionaskerProtectedForms);

# A list of arrays. The first element in each array is a string, the
# question to be asked. The second element is a subroutine which is
# passed the answer as the first argument.
@QuestionaskerQuestions =
(['What is the first letter of this question?' => sub { shift =~ /^\s*W\s*$/i }],
['How many letters are in the word "four"?' => sub { shift =~ /^\s*(4|four)\s*$/i }],
['Tell me any number between 1 and 10' => sub { shift =~ /^\s*([1-9]|10|one|two|three|four|five|six|seven|eight|nine|ten)\s*$/ }],
["How many lives does a cat have?" => sub { shift =~ /^\s*(7|seven|9|nine)\s*$/i }],
["What is 2 + 4?" => sub { shift =~ /^\s*(6|six)\s*$/i }],
);

# The page name for exceptions, if defined. Every page linked to via
# WikiWord or [[free link]] is considered to be a page which needs
# questions asked. All other pages do not require questions asked. If
# not set, then all pages need questions asked.
$QuestionaskerRequiredList = '';

# If a user answers a question correctly, remember this in the cookie
# and don't ask any further questions. The name of the parameter in
# the cookie can be changed should a spam bot target this module
# specifically. Changing the secret key will force all users to answer
# another question.
$QuestionaskerRememberAnswer = 1;
$QuestionaskerSecretKey = 'question';

# Forms using one of the following classes are protected.
%QuestionaskerProtectedForms = ('comment' => 1,
'edit upload' => 1,
'edit text' => 1,);

push(@MyInitVariables, \&QuestionaskerInit);

sub QuestionaskerInit {
$QuestionaskerRequiredList = FreeToNormal($QuestionaskerRequiredList);
$AdminPages{$QuestionaskerRequiredList} = 1;
$CookieParameters{$QuestionaskerSecretKey} = '';
$InvisibleCookieParameters{$QuestionaskerSecretKey} = 1;
}

*OldQuestionaskerDoPost = *DoPost;
*DoPost = *NewQuestionaskerDoPost;

sub NewQuestionaskerDoPost {
my(@params) = @_;
my $id = FreeToNormal(GetParam('title', undef));
my $preview = GetParam('Preview', undef); # case matters!
my $question_num = GetParam('question_num', undef);
my $answer = GetParam('answer', undef);
unless (UserIsEditor()
or $QuestionaskerRememberAnswer && GetParam($QuestionaskerSecretKey, 0)
or $preview
or $QuestionaskerQuestions[$question_num][1]($answer)
or QuestionaskerException($id)) {
print GetHeader('', T('Edit Denied'), undef, undef, '403 FORBIDDEN');
print $q->p(T('You did not answer correctly.'));
print GetFormStart(), QuestionaskerGetQuestion(1),
(map { $q->input({-type=>'hidden', -name=>$_,
-value=>UnquoteHtml(GetParam($_))}) }
qw(title text oldtime summary recent_edit aftertext)), $q->end_form;
PrintFooter();
# logging to the error log file of the server
# warn "Q: '$QuestionaskerQuestions[$question_num][0]', A: '$answer'\n";
return;
}
# Set the secret key only if a question has in fact been answered
if (not GetParam($QuestionaskerSecretKey, 0)
and $QuestionaskerQuestions[$question_num][1]($answer)) {
SetParam($QuestionaskerSecretKey, 1)
}
return (OldQuestionaskerDoPost(@params));
}

*OldQuestionaskerGetEditForm = *GetEditForm;
*GetEditForm = *NewQuestionaskerGetEditForm;

sub NewQuestionaskerGetEditForm {
return QuestionAddTo(OldQuestionaskerGetEditForm(@_));
}

*OldQuestionaskerGetCommentForm = *GetCommentForm;
*GetCommentForm = *NewQuestionaskerGetCommentForm;

sub NewQuestionaskerGetCommentForm {
return QuestionAddTo(OldQuestionaskerGetCommentForm(@_));
}

sub QuestionAddTo {
my $form = shift;
if (not $upload
and not QuestionaskerException(GetId())
and not $QuestionaskerRememberAnswer && GetParam($QuestionaskerSecretKey, 0)
and not UserIsEditor()) {
my $question = QuestionaskerGetQuestion();
$form =~ s/(.*)<p>(.*?)<label for="username">/$1$question<p>$2<label for="username">/;
}
return $form;
}

sub QuestionaskerGetQuestion {
my $need_button = shift;
my $button = $need_button ? $q->submit(-value=>T('Go!')) : '';
my $question_number = int(rand(scalar(@QuestionaskerQuestions)));
return $q->div({-class=>'question'},
$q->p(T('To save this page you must answer this question:')),
$q->blockquote($q->p($QuestionaskerQuestions[$question_number][0]),
$q->p($q->input({-type=>'text', -name=>'answer'}),
$q->input({-type=>'hidden', -name=>'question_num',
-value=>$question_number}),
$button)));
}

sub QuestionaskerException {
my $id = shift;
return 0 unless $QuestionaskerRequiredList and $id;
my $data = GetPageContent($QuestionaskerRequiredList);
if ($WikiLinks) {
while ($data =~ /$LinkPattern/g) {
return 0 if FreeToNormal($1) eq $id;
}
}
if ($FreeLinks) {
while ($data =~ /\[\[$FreeLinkPattern\]\]/g) {
return 0 if FreeToNormal($1) eq $id;
}
}
return 1;
}