#!/usr/bin/perl
#
# The LearningOnline Network
#
# $Id: parse_activity_log.pl,v 1.3 2004/08/19 21:08:46 matthew Exp $
#
# Copyright Michigan State University Board of Trustees
#
# This file is part of the LearningOnline Network with CAPA (LON-CAPA).
#
# LON-CAPA 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 2 of the License, or
# (at your option) any later version.
#
# LON-CAPA 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 LON-CAPA; if not, write to the Free Software
# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
#
# /home/httpd/html/adm/gpl.txt
#
# http://www.lon-capa.org/
#
#--------------------------------------------------------------------
#
# Exit codes
#   0     Everything is okay
#   1     Another copy is running on this course
#   2     Activity log does not exist
#   3     Unable to connect to database
#   4     Unable to create database tables
#   5     Unspecified error?
#

use strict;
use DBI;
use lib '/home/httpd/lib/perl/Apache';
use lonmysql();
use Time::HiRes();
use Getopt::Long();
use IO::File;

#
# Determine parameters
my ($help,$course,$domain,$drop,$file,$time_run,$nocleanup,$log);
&Getopt::Long::GetOptions( "course=s"  => \$course,
                           "domain=s"  => \$domain,
                           "help"      => \$help,
                           "logfile=s" => \$file,
                           "timerun"   => \$time_run,
                           "nocleanup" => \$nocleanup,
                           "drop"      => \$drop,
                           "log"       => \$log);
if (! defined($course) || $help) {
    print<<USAGE;
parse_activity_log.pl

Process a lon-capa activity log into a database.
Parameters:
   course             Required
   domain             Optional
   drop               optional   if present, drop all course 
                                 specific activity log tables.
   file               optional   Specify the file to parse, including path
   time               optional   if present, print out timing data
   nocleanup          optional   if present, do not remove old files
   log                optional   if present, prepare log file of activity
Examples:
  $0 -course=123456abcdef -domain=msu
  $0 -course=123456abcdef -file=activity.log
USAGE
    exit;
}

##
## Set up timing code
my $time_this = \&nothing;
if ($time_run) {
    $time_this = \&time_action;
}
my $initial_time = Time::HiRes::time;

##
## Read in configuration parameters
##
my %perlvar;
&initialize_configuration();
if (! defined($domain) || $domain eq '') {
    $domain = $perlvar{'lonDefDomain'};
}
&update_process_name($course.'@'.$domain);

##
## Set up logging code
my $logthis = \&nothing;
if ($log) {
    my $logfile = "/tmp/parse_activity_log.log.".time;
    print STDERR "$0: logging to $logfile".$/;
    if (! open(LOGFILE,">$logfile")) {
        die "Unable to open $logfile for writing.  Run aborted.";
    } else {
        $logthis = \&log_to_file;
    }
}


##
## Determine filenames
##
my $sourcefilename;   # activity log data
my $newfilename;      # $sourcefilename will be renamed to this
my $sql_filename;     # the mysql backup data file name.
my $error_filename;   # Errors in parsing the activity log will be written here
if ($file) {
    $sourcefilename = $file;
} else {
    $sourcefilename = &get_filename($course,$domain);
}
$sql_filename = $sourcefilename;
$sql_filename =~ s|[^/]*$|activity.log.sql|;
$error_filename = $sourcefilename;
$error_filename =~ s|[^/]*$|activity.log.errors|;
$logthis->('Beginning logging '.time);

##
## There will only be a $newfilename file if a copy of this program is already
## running.
my $newfilename = $sourcefilename.'.processing';
if (-e $newfilename) {
    warn "$newfilename exists";
    $logthis->($newfilename.' exists');
    exit 2;
}

if (-e $sourcefilename) {
    $logthis->('renaming '.$sourcefilename.' to '.$newfilename);
    rename($sourcefilename,$newfilename);
    $logthis->("renamed $sourcefilename to $newfilename");
} else {
    my $command = 'touch '.$newfilename;
    $logthis->($command);
    system($command);
    $logthis->('touch was completed');
}

##
## Table definitions
##
my $prefix = $course.'_'.$domain.'_';
my $student_table = $prefix.'students';
my $student_table_def = 
{ id => $student_table,
  permanent => 'no',
  columns => [
              { name => 'student_id',
                type => 'MEDIUMINT UNSIGNED',
                restrictions => 'NOT NULL',
                auto_inc => 'yes', },
              { name => 'student',
                type => 'VARCHAR(100) BINARY',
                restrictions => 'NOT NULL', },
              ],
      'PRIMARY KEY' => ['student_id',],
          };

my $res_table = $prefix.'resource';
my $res_table_def = 
{ id => $res_table,
  permanent => 'no',
  columns => [{ name => 'res_id',
                type => 'MEDIUMINT UNSIGNED',
                restrictions => 'NOT NULL',
                auto_inc     => 'yes', },
              { name => 'resource',
                type => 'MEDIUMTEXT',
                restrictions => 'NOT NULL'},
              ],
  'PRIMARY KEY' => ['res_id'],
};

my $action_table = $prefix.'actions';
my $action_table_def =
{ id => $action_table,
  permanent => 'no',
  columns => [{ name => 'action_id',
                type => 'MEDIUMINT UNSIGNED',
                restrictions => 'NOT NULL',
                auto_inc     => 'yes', },
              { name => 'action',
                type => 'VARCHAR(100)',
                restrictions => 'NOT NULL'},
              ],
  'PRIMARY KEY' => ['action_id',], 
};

my $machine_table = $prefix.'machine_table';
my $machine_table_def =
{ id => $machine_table,
  permanent => 'no',
  columns => [{ name => 'machine_id',
                type => 'MEDIUMINT UNSIGNED',
                restrictions => 'NOT NULL',
                auto_inc     => 'yes', },
              { name => 'machine',
                type => 'VARCHAR(100)',
                restrictions => 'NOT NULL'},
              ],
  'PRIMARY KEY' => ['machine_id',],
 };

my $activity_table = $prefix.'activity';
my $activity_table_def = 
{ id => $activity_table,
  permanent => 'no',
  columns => [
              { name => 'res_id',
                type => 'MEDIUMINT UNSIGNED',
                restrictions => 'NOT NULL',},
              { name => 'time',
                type => 'DATETIME',
                restrictions => 'NOT NULL',},
              { name => 'student_id',
                type => 'MEDIUMINT UNSIGNED',
                restrictions => 'NOT NULL',},
              { name => 'action_id',
                type => 'MEDIUMINT UNSIGNED',
                restrictions => 'NOT NULL',},
              { name => 'idx',                # This is here in case a student
                type => 'MEDIUMINT UNSIGNED', # has multiple submissions during
                restrictions => 'NOT NULL',   # one second.  It happens, trust
                auto_inc     => 'yes', },     # me.
              { name => 'machine_id',
                type => 'MEDIUMINT UNSIGNED',
                restrictions => 'NOT NULL',},
              { name => 'action_values',
                type => 'MEDIUMTEXT', },
              ], 
      'PRIMARY KEY' => ['res_id','time','student_id','action_id','idx'],
};
my @Activity_Table = ($activity_table_def);
my @ID_Tables = ($student_table_def,$res_table_def,
                 $action_table_def,$machine_table_def);
                       

##
## End of table definitions
##

# 
$logthis->('Connectiong to mysql');
&Apache::lonmysql::set_mysql_user_and_password($perlvar{'lonSqlUser'},
                                               $perlvar{'lonSqlAccess'});
if (!&Apache::lonmysql::verify_sql_connection()) {
    warn "Unable to connect to MySQL database.";
    $logthis->("Unable to connect to MySQL database.");
    exit 3;
}

$logthis->('SQL connection is up');

if ($drop) { &drop_tables(); $logthis->('dropped tables'); }

if (-s $sql_filename) {
    # if ANY one of the tables does not exist, load the tables from the
    # backup.
    my @Current_Tables = &Apache::lonmysql::tables_in_db();
    my %Found;
    foreach my $tablename (@Current_Tables) {
        foreach my $table (@Activity_Table,@ID_Tables) {
            if ($tablename eq  $table->{'id'}) {
                $Found{$tablename}++;
            }
        }
    }
    foreach my $table (@Activity_Table,@ID_Tables) {    
        if (! $Found{$table->{'id'}}) {
            $time_this->();
            &load_backup_tables($sql_filename);
            $time_this->('load backup tables');
            last;
        }
    }
}

##
## Ensure the tables we need exist
# create_tables does not complain if the tables already exist
$logthis->('creating tables');
if (! &create_tables()) {
    warn "Unable to create tables";
    $logthis->('Unable to create tables');
    exit 4;
}

##
## Read the ids used for various tables
$logthis->('reading id tables');
&read_id_tables();
$logthis->('finished reading id tables');

##
## Set up the errors file
my $error_fh = IO::File->new(">>$error_filename");

##
## Parse the course log
$logthis->('processing course log');
if (-s $newfilename) {
    my $result = &process_courselog($newfilename,$error_fh);
    if (! defined($result)) {
        # Something went wrong along the way...
        $logthis->('process_courselog returned undef');
        exit 5;
    } elsif ($result > 0) {
        $time_this->();
        $logthis->('process_courselog returned '.$result.' backup up tables');
        &backup_tables($sql_filename);
        $time_this->('write backup tables');
    }
}
close($error_fh);

##
## Clean up the filesystem
&Apache::lonmysql::disconnect_from_db();
unlink($newfilename) if (-e $newfilename && ! $nocleanup);

##
## Print timing data
$logthis->('printing timing data');
if ($time_run) {
    my $elapsed_time = Time::HiRes::time - $initial_time;
    print "Overall time: ".$elapsed_time.$/;
    print &outputtimes();
    $logthis->("Overall time: ".$elapsed_time);
    $logthis->(&outputtimes());
}

if ($log) {
    close LOGFILE;
}

exit 0;   # Everything is okay, so end here before it gets worse.

########################################################
########################################################
##
##                 Process Course Log
##
########################################################
########################################################
#
# Returns the number of lines in the activity.log file that were processed.
sub process_courselog {
    my ($inputfile,$error_fh) = @_;
    if (! open(IN,$inputfile)) {
        warn "Unable to open '$inputfile' for reading";
        $logthis->("Unable to open '$inputfile' for reading");
        return undef;
    }
    my ($linecount,$insertcount);
    my $dbh = &Apache::lonmysql::get_dbh();
    #
    # Timing variables
    my @RowData;
    while (my $line=<IN>){
        # last if ($linecount > 1000);
        #
        # Bulk storage variables
        $time_this->();
        chomp($line);
        $linecount++;
        # print $linecount++.$/;
        my ($timestamp,$host,$log)=split(/\:/,$line,3);
        $time_this->('splitline');
        #
        # $log has the actual log entries; currently still escaped, and
        # %26(timestamp)%3a(url)%3a(user)%3a(domain)
        # then additionally
        # %3aPOST%3a(name)%3d(value)%3a(name)%3d(value)
        # or
        # %3aCSTORE%3a(name)%3d(value)%26(name)%3d(value)
        #
        # get delimiter between timestamped entries to be &&&
        $log=~s/\%26(\d{9,10})\%3a/\&\&\&$1\%3a/g;
        $log = &unescape($log);
        $time_this->('translate_and_unescape');
        # now go over all log entries 
        if (! defined($host)) { $host = 'unknown'; }
        my $machine_id = &get_id($machine_table,'machine',$host);
        my $prevchunk = 'none';
        foreach my $chunk (split(/\&\&\&/,$log)) {
            my $warningflag = '';
            $time_this->();
	    my ($time,$res,$uname,$udom,$action,@values)= split(/:/,$chunk);
            my $student = $uname.':'.$udom;
            if (! defined($res) || $res =~ /^\s*$/) {
                $res = '/adm/roles';
                $action = 'LOGIN';
            }
            if ($res =~ m|^/prtspool/|) {
                $res = '/prtspool/';
            }
            if (! defined($action) || $action eq '') {
                $action = 'VIEW';
            }
            if ($action !~ /^(LOGIN|VIEW|POST|CSTORE|STORE)$/) {
                $warningflag .= 'action';
                print $error_fh 'full log entry:'.$log.$/;
                print $error_fh 'error on chunk:'.$chunk.$/;
                $logthis->('(action) Unable to parse '.$/.$chunk.$/.
                         'got '.
                         'time = '.$time.$/.
                         'res  = '.$res.$/.
                         'uname= '.$uname.$/.
                         'udom = '.$udom.$/.
                         'action='.$action.$/.
                         '@values = '.join(':',@values));
                next; #skip it if we cannot understand what is happening.
            }
            if (! defined($student) || $student eq ':') {
                $student = 'unknown';
                $warningflag .= 'student';
            }
            if (! defined($res) || $res =~ /^\s*$/) {
                $res = 'unknown';
                $warningflag .= 'res';
            }
            if (! defined($action) || $action =~ /^\s*$/) {
                $action = 'unknown';
                $warningflag .= 'action';
            }
            if (! defined($time) || $time !~ /^\d+$/) {
                $time = 0;
                $warningflag .= 'time';
            }
            #
            $time_this->('split_and_error_check');
            my $student_id = &get_id($student_table,'student',$student);
            my $res_id     = &get_id($res_table,'resource',$res);
            my $action_id  = &get_id($action_table,'action',$action);
            my $sql_time   = &Apache::lonmysql::sqltime($time);
            #
            if (! defined($student_id) || $student_id eq '') { 
                $warningflag.='student_id'; 
            }
            if (! defined($res_id) || $res_id eq '') { 
                $warningflag.='res_id'; 
            }
            if (! defined($action_id) || $action_id eq '') { 
                $warningflag.='action_id'; 
            }
            if ($warningflag ne '') {
                print $error_fh 'full log entry:'.$log.$/;
                print $error_fh 'error on chunk:'.$chunk.$/;
                $logthis->('warningflag ('.$warningflag.') on chunk '.
                           $/.$chunk.$/.'prevchunk = '.$/.$prevchunk);
                $prevchunk .= $chunk;
                next; # skip this chunk
            }
            #
            my $values = $dbh->quote(join('',@values));
            $time_this->('get_ids');
            #
            my $row = [$res_id,
                       qq{'$sql_time'},
                       $student_id,
                       $action_id,
                       qq{''},        # idx
                       $machine_id,
                       $values];
            push(@RowData,$row);
            $time_this->('push_row');
            $prevchunk = $chunk;
            #
        }
        $time_this->();
        if ((scalar(@RowData) > 0) && ($linecount % 100 == 0)) {
            my $result = &Apache::lonmysql::bulk_store_rows($activity_table,
                                                            undef,
                                                            \@RowData);
            # $logthis->('result = '.$result);
            $time_this->('bulk_store_rows');
            if (! defined($result)) {
                my $error = &Apache::lonmysql::get_error();
                warn "Error occured during insert.".$error;
                $logthis->('error = '.$error);
            }
            undef(@RowData);
        }
    }
    if (@RowData) {
        $time_this->();
        $logthis->('storing '.$linecount);
        my $result = &Apache::lonmysql::bulk_store_rows($activity_table,
                                                        undef,
                                                        \@RowData);
        $logthis->('result = '.$result);
        $time_this->('bulk_store_rows');
        if (! defined($result)) {
            my $error = &Apache::lonmysql::get_error();
            warn "Error occured during insert.".$error;
            $logthis->('error = '.$error);
        }
        undef(@RowData);
    }
    close IN;
#    print "Number of lines: ".$linecount.$/;
#    print "Number of inserts: ".$insertcount.$/;
    return $linecount;
}


##
## Somtimes, instead of doing something, doing nothing is appropriate.
sub nothing {
    return;
}

##
## Logging routine
##
sub log_to_file {
    my ($input)=@_;
    print LOGFILE $input.$/;
}

##
## Timing routines
##
{
    my %Timing;
    my $starttime;

sub time_action {
    my ($key) = @_;
    if (defined($key)) {
        $Timing{$key}+=Time::HiRes::time-$starttime;
        $Timing{'count_'.$key}++;
    }
    $starttime = Time::HiRes::time;
}

sub outputtimes {
    my $Str;
    if ($time_run) {
        $Str = "Timing Data:".$/;
        while (my($k,$v) = each(%Timing)) {
            next if ($k =~ /^count_/);
            my $count = $Timing{'count_'.$k};
            $Str .= 
                '  '.sprintf("%25.25s",$k).
                '  '.sprintf('% 8d',$count).
                '  '.sprintf('%12.5f',$v).$/;
        }
    }
    return $Str;
}

}


##
## Use mysqldump to store backups of the tables
##
sub backup_tables {
    my ($sql_filename) = @_;
    my $command = qq{mysqldump --opt loncapa };
                             
    foreach my $table (@ID_Tables,@Activity_Table) {
        my $tablename = $table->{'id'};
        $command .= $tablename.' ';
    }
    $command .= '>'.$sql_filename;
    $logthis->($command);
    system($command);
}

##
## Load in mysqldumped files
##
sub load_backup_tables {
    my ($sql_filename) = @_;
    return undef if (! -e $sql_filename);
    # Check for .my.cnf
    my $command = 'mysql -e "SOURCE '.$sql_filename.'" loncapa';
    $logthis->('loading previously saved sql table'.$/.$command);
    system($command);
    $logthis->('finished loading old data');
}

##
## 
##
sub initialize_configuration {
    # Fake it for now:
    $perlvar{'lonSqlUser'} = 'www';
    $perlvar{'lonSqlAccess'} = 'localhostkey';
    $perlvar{'lonUsersDir'} = '/home/httpd/lonUsers';
    $perlvar{'lonDefDomain'} = '103';
}

sub update_process_name {
    my ($text) = @_;
    $0 = 'parse_activity_log.pl: '.$text;
}

sub get_filename {
    my ($course,$domain) = @_;
    my ($a,$b,$c,undef) = split('',$course,4);
    return "$perlvar{'lonUsersDir'}/$domain/$a/$b/$c/$course/activity.log";
}

sub create_tables {
    foreach my $table (@ID_Tables,@Activity_Table) {
        my $table_id = &Apache::lonmysql::create_table($table);
        if (! defined($table_id)) {
            warn "Unable to create table ".$table->{'id'}.$/;
            warn &Apache::lonmysql::build_table_creation_request($table).$/;
            return 0;
        }
    }
    return 1;
}

sub drop_tables {
    foreach my $table (@ID_Tables,@Activity_Table) {
        my $table_id = $table->{'id'};
        &Apache::lonmysql::drop_table($table_id);
    }
}

#################################################################
#################################################################
##
## Database item id code
##
#################################################################
#################################################################
{ # Scoping for ID lookup code
    my %IDs;

sub read_id_tables {
    foreach my $table (@ID_Tables) {
        my @Data = &Apache::lonmysql::get_rows($table->{'id'});
        my $count = 0;
        foreach my $row (@Data) {
            $IDs{$table->{'id'}}->{$row->[1]} = $row->[0];
        }
    }
    return;
}

sub get_id {
    my ($table,$fieldname,$value) = @_;
    if (exists($IDs{$table}->{$value})) {
        return $IDs{$table}->{$value};
    } else {
        # insert into the table - if the item already exists, that is
        # okay.
        my $result = &Apache::lonmysql::store_row($table,[undef,$value]);
        if (! defined($result)) {
            warn("Got error on id insert for $value\n".&Apache::lonmysql::get_error());
        }
        # get the id
        my @Data = 
            &Apache::lonmysql::get_rows($table,qq{$fieldname='$value'});
        if (@Data) {
            $IDs{$table}->{$value}=$Data[0]->[0];
            return $IDs{$table}->{$value};
        } else {
            $logthis->("Unable to retrieve id for $table $fieldname $value");
            return undef;
        }
    }
}

} # End of ID scoping


###############################################################
###############################################################
##
##   The usual suspects
##
###############################################################
###############################################################
sub escape {
    my $str=shift;
    $str =~ s/(\W)/"%".unpack('H2',$1)/eg;
    return $str;
}

sub unescape {
    my $str=shift;
    $str =~ s/%([a-fA-F0-9][a-fA-F0-9])/pack("C",hex($1))/eg;
    return $str;
}