#!perl

#############################################################################
# authen_LTI.conf
# Configuration for using LTI authentication.
# To enable this file, uncomment the appropriate lines in localOverrides.conf
#############################################################################

# Set debug_lti_parameters  to 1 to have LTI calling parameters printed to HTML page for
# debugging.  This is useful when setting things up for the first time because
# different LMS systems have different parameters
$debug_lti_parameters = 1; 

# To get more information on passing grades back to the LMS enmass set debug_lti_grade_passback
# to one.  And set the LTIMassUpdateInterval to 60 (seconds).
$debug_lti_grade_passback = 0;

# This will print into the apache log the success or failure of updating each user/set.
# If the set has "no lis_source_did" then that set hasn't been assigned, or the user is an instructor
# and not a student.

# Setting both debug_lti_parameters and debug_lti_grade_passback will cause the full request and 
# response between the LMS and WW to be printed into apache error log file for each
# user/set  update of the grade.

# The switches above can be set in course.conf to enable debugging for just one course.

# If you want even more information enable the debug facility for SubmitGrade.pm in 
# the WeBWorK::Constants file.  
# This will print extensive debug messages for all courses.

# This first section enables LTI authentication.
# Failover to Basic_TheLastOption is necessary to authenticate with
# cookie keys.  

###################
$authen{user_module} = [ 
	{  "*" => "WeBWorK::Authen::LTIAdvanced", }, #preferred authorization method
	{  "*" => "WeBWorK::Authen::Basic_TheLastOption",}  #fallback authorization method
];

# If the preferred module is an external authentication
# module but the sequence includes an internal authentication
# system, e.g., Basic_TheLastOption, then the following line
# must be commented out.
# If it is uncommented and the value = 1,
# then, if the authentication sequence reaches 
# Basic_TheLastOption, then WeBWorK::Login
# will display a screen directing the user
# back to an external authentication system.
# This prevents you from attempting to login in to WeBWorK directly.

#$external_auth=1;

# NOTE:  If external authentication is disabled
# then you should probably also prevent students
# from changing their passwords (because they cant use them).
# To do this ucomment the following

#  $permissionLevels{change_password} = "ta";

################################################################################
# LTI Basic parameters
################################################################################

################################################################################
# LTI Preferred Source of Username
################################################################################

# If both lis_person_sourcedid (or one of its variants)
# and lis_person_contact_email_primary are present,
# then one needs to state which one is preferred
# as the WeBWorK username.
# The considerations are (1) ensuring that usernames
# are unique and (2) being as compatible as possible with the practices
# of the institutions that are being served in a site.
# If a site is only being used be students from a single
# institution and the value  lis_person_sourcedid  is
# unique across the population and matches the  logon username
# at that institution, then lis_person_sourcedid is
# probably the better choice.
# On the other hand, if a site is serving a population
# from several institutions and  lis_person_sourcedid  is not
# necessarily unique across the population, then
# lis_person_contact_email_primary is the better choice.
# Because the WeBWorK username must be unique across
# the population served by a site, the default if
# neither line is uncommented will be the value of
# lis_person_contact_email_primary.

# NOTE: Even if a course management system sends 
# one of the common misspellings of "lis_person_sourcedid", i.e.,
# lis_person_sourced_id, lis_person_source_id, and
# lis_person_sourceid, one must nevertheless use
# the correct spelling here, i.e. "lis_person_sourcedid".

#$preferred_source_of_username = "lis_person_sourcedid";
$preferred_source_of_username = "lis_person_contact_email_primary";

# Some LMS systems, Blackboard in particular, do not send lis_person_sourcedid
# if you enable this flag and have $preferred_source_of_username set to
# lis_person_contact_email_primary, then webwork will strip off the address 
# portion of the email and just use the username.  

#$strip_address_from_email = 1;

################################################################################
# LTI Preferred source of Student Id
################################################################################

# If preferred_source_of_student_id is not set, WeBWorK will look in the LTI
# parameter 'custom_student_id.' If preferred_source_of_student_id is set, then
# WeBWorK will look in the LTI parameter specified below. This parameter may be
# dependendent on the LMS. E.G., In D2L, student_id is stored in OrgDefinedId and
# the corresponding LTI parameter is called ext_d2l_orgdefinedid.

#$preferred_source_of_student_id = "ext_d2l_orgdefinedid";


################################################################################
# LTI - Should an attempt be made to "fix" multi-byte characters in the
# $r->{paramcache} which would otherwise trigger errors in the Net:OAuth code.
# Set to 1 to enable the beta code for the fix to this issue.
#
# Error message that had been triggered:
#      Net::OAuth warning: your OAuth message appears to contain some multi-byte
#      characters that need to be decoded via Encode.pm or a PerlIO layer first.
#      This may result in an incorrect signature.
#      at /usr/share/perl5/Net/OAuth/Message.pm line 106.
#
# See: https://metacpan.org/pod/release/KGRENNAN/Net-OAuth-0.28/lib/Net/OAuth.pm
#      http://webwork.maa.org/moodle/mod/forum/discuss.php?d=4484
#      http://webwork.maa.org/moodle/mod/forum/discuss.php?d=3949
#      http://webwork.maa.org/moodle/mod/forum/discuss.php?d=3985
#

# This is NOT turned on by default. Try it if needed, but it may break something (hopefully not).
#$allow_WW_LTI_code_to_fix_what_appear_as_multi_byte_characters = 1;

################################################################################
# LTI Basic Authentication Parameters 
################################################################################

# This "shared secret" is entered in the LMS request form and needs to be
# match the entry here.  This is used to validate all requests between the
# LMS and WeBWorK

# You should choose your own secret word for security and should treat it
# like a password. 

$LTIBasicConsumerSecret = "";  #This must be set  

# The purpose of the LTI nonces is to prevent man-in-the-middle attacks.
# The NonceLifeTime (in seconds) must be short enought to prevent
# at least casual man-in-the-middle attacks but
# long enough to accommodate normal server and networking delays
# (and perhaps non-synchronization of server time clocks).
#

$NonceLifeTime=60; # in seconds

# WeBWorK will automatically create users when logging in via the LMS for the
# first time.  If the following flag is enabled then it will also keep the
# user demographic data up to date with the LMS.  If a users information change
# in the LMS then it will change in WeBWorK. However, any changes to the
# student data via WeBWorK will be overwritten the next time the student
# logs in.  

$LMSManageUserData=1;


# NOTE:  If mange user data is enabled  then you should probably also
# prevent students from changing their email because the changes
# will be overwritten.  To do this ucomment the following

#  $permissionLevels{change_email} = "ta";


# This allows you to override the URL that Oauth will use to validate the 
# authentication.  This is important if you have some sort of setup (e.g. load
# distributing) where the path in the LMS does not match the path that ends up 
# in the webwork page 

#$LTIBasicToThisSiteURL = "";

################################################################################
# Authorization system   LTI:  LMS Grade Passback
################################################################################

# WeBWorK can automatically report grades back to your LMS.  However the
# system is reasonably restrictive.  When you create an LTI link in your
# LMS you can choose to have that LTI link have a grade associated to it.
# WeBWorK can report back a single percentage as the "grade" for that link.
# There are two modes under which this can occur.
#
# Single Course Grade Mode:  $LTIGradeMode = "course";
# 
# In this mode you create a single Link/Assignment which points to your
# WeBWorK Course address.  E.G. In Blackboard
# Name: WeBWorK
# URL: https://webwork.university.edu/webwork2/CourseName
# Check Yes:  This link is to a Tool Provider
# Enable Evaluation: Yes
# Points Possible: 100
#   Students will receive a LMS grade associated to the Link/Assignment
# which is determined by their percentage total homework grade in WeBWorK.
# This total homework grade is the same as the grade that is reported on the
# grades page.  You can change the weight of sets by altering the weight of
# the problems in the set.  
#
# Individual Homework Grade Mode:  $LTIGradeMode = "homework";
#
# In this mode you create a single Link/Assignment for *every* homework set in
# the course.  The address should be the address of that set in the Course.
# E.G. in Blackboard
# Name: Set Name
# URL: https://webwork.university.edu/webwork2/CourseName/SetName
# Check Yes:  This link is to a Tool Provider
# Enable Evaluation: Yes
# Points Possible: 100
#   Students will receive a grade for each Link/Assignment which is determined
# by their percentage homework grade on the Set which the Link/Assignment
# points to.  Students need to use the Link/Assignment in the LMS at least once
# to enable grade passback.  In particular when working in this mode it is
# recommended that you only allow students to log in via the LMS.  
#
#    Note: For both of these modes only the grades are passed back.  In
# particular nothing else about the Link/Assignment in the LMS and the
# homework set in WeBWorK is syncronized.  In particular the total number of
# points/problems, the due dates, the open dates are not kept in sync
# automatically.  

#$LTIGradeMode = "course";
#$LTIGradeMode = "homework";

# When set this variable sends grades back to the LMS every time a user
# submits an answer.  This keeps students grades up to date but can be
# a drain on the server.

$LTIGradeOnSubmit = 1;

# The system periodically updates student grades on the LMS.  This
# variable controls how often that happens.  Set to -1 to disable.  

$LTIMassUpdateInterval = 86400; #in seconds

################################################################################
# Authorization system   LTI:  LMS Roles Mapped to WeBWorK Roles
################################################################################

# You may need to customize this hash to take into account the roles
# that are used in your LMS.  Set the debug_lti_parameters flag to see
# what roles are being reported to WeBWorK by your LMS

%LMSrolesToWeBWorKroles = (
			   "librarian" => "guest",
			   "observer" => "guest",
			   "visitor" => "guest",
			   "Guest"  => "guest",
			   "Designer" => "professor",
			   "instructor" => "professor",
			   "Instructor" => "professor",
			   "Faculty" => "professor",
			   "Teacher" => "professor",
			   "Student" => "student",
			   "Learner" => "student",
			   "student" => "student",
			   "AI/TA" => "ta",
			   "TA" => "ta",
			   "Teaching Assistant" => "ta",
			   "Teaching Assistant (TA)" => "ta",
			   "Non-editing teacher" => "ta",
			   "Grader" => "ta",
    );

# For security reasons accounts with high permissions should not be auto
# created via LTI requests.  Set this variable to "professor" if you want
# professor accounts to be created automatically

$LTIAccountCreationCutoff = "ta";

################################################################################
# Local routines  
################################################################################

# These local routines can be used to modify and override various elements of
# the authentication process.

################################################################################
# Local routine to modify users
################################################################################

# When users are added to the system WeBWorK will do its best to fill out
# user information.  However, institutions can add code to the following
# routine to set fields not normally set by WeBWorK.  E.G.  The student ID
# field.

#$LTI_modify_user = sub {
#  # The self object from LTIAdvanced.pm
#  my $self = shift;
#  # The user object to be modified
#  my $user = shift;
#
#  # Parse context_id for additional information.  E.G.  
#  my @course_id=split /-/, $self -> {"context_id"};
#  $user->{"section"} = $course_id[4];

#  };


################################################################################
# Local routine to modify user sets
################################################################################

# When users are added to the system they are also assigned all visible sets
# This routine can be used to modify the sets before they are assigned.  E.G.
# extend due dates based off the number of problems students have to do 

#$LTI_modify_user_set = sub {
#  # The self object from LTIAdvanced.pm
#  my $self = shift;
#  my $globalSet = shift;
#  # The userSet object to be modified
#  my $userSet = shift;

#   my $numberOfSetsAssigned = $self->{numberOfSetsAssigned};
#   my $daysPerSetMakeup = 2;
#   my $reasonableNumberOfDays = $numberOfSetsAssigned*$daysPerSetMakeup +1;
#   if ($reasonableNumberOfDays < 2) {$reasonableNumberOfDays = 2;}

#   my $niceDueTime = $globalSet->due_date + $reasonableNumberOfDays*86400;
#   my $niceAnswerTime = $niceDueTime + 600;
  
#   $userSet->due_date($niceDueTime);
#   $userSet->answer_date($niceAnswerTime);

#};
  

1; #final line of the file to reassure perl that it was read properly.