#!/usr/bin/env python

#
# Display student marks stored in a CSV file on the course account.
#
# Constraints:
#   MARK_FILE must exist and be CSV-formatted as follows:
#               first line: assignment names
#               second line: "out-of values"
#               remaining lines: student user-id (<=8 characters) followed by their marks on each assignment
# Author:    Morgan Grainger
# Version:   1.0   2008-April-24
#            1.1   2008-May-26: modify CSV file format.
#            1.2   ???????????: provide easier customization via variables, added ROOT_USERS, and...?  (Jonathan Templin?  Ian Goldberg?  Others?)
#            1.3   2010-Mar-04: Check for shtml *or* php standard includes, and also autodetection of course name and root users read in using Classlist.pm to reduce start-of-term overhead. (Terry Vaskor)
#            1.3.2 2010-Aug-27: CGI debugging output, bug fixing: improved handling of marks file format (leading empty fields + various newline conventions), long userid handling. (Terry Vaskor, with cgitb usage inherited from anonymous modifications to CS 241 script)
#            1.3.3 2010-Sep-07: ldapsearch command change; incompatible with Solaris systems, but allows operation on Linux systems.  (Terry Vaskor, Ian Goldberg)
#            1.3.4 2010-Sep-07: Bug fix for search in 1.3.3
#
#

import os
import urllib2
import cgi
import re
import pwd
import subprocess

import cgitb
cgitb.enable()  # for troubleshooting


# COURSE OFFERING-SPECIFIC INFORMATION
# This must be modified by course staff for the script to behave properly.

# TODO:
# Replace I_clicker flag with a root directory for marks files, and then
# an explicit list of files to find in that directory.

#if I-clicker is part of the course, set to True, or else set to False
I_clicker = False 


# The rest will be detected automatically

CL_INFO_PATH = "/u/isg/bin/get_classlist_info";
FORMAT_USER_PATH = "/u/isg/bin/format_userid";

def getName( userId ):
        try:
                # userId has already had the above RE matched to it, so
                # including it in a command line is safe
                data = subprocess.Popen(['ldapsearch', '-LLLx', '-h', 'uwldap.uwaterloo.ca', '-b', 'dc=uwaterloo,dc=ca', 'uid=' + userId, 'cn'], stdout=subprocess.PIPE ).stdout.readlines()

                for line in data:
                    tag, val = line.split(": ", 1)
                    if tag == "cn":
                        return val
        except:
                return None


# Course Name:
Course = pwd.getpwuid(os.getuid())[0]

# Can look up anyone's marks by specifying ?user=<userid> at the end of the  URL
# This will be read in from .coursestaff.$term; explicitly strip the trailing newlines.
ROOT_USERS = [user.strip("\n") for user in subprocess.Popen([CL_INFO_PATH, '-r', 'type', '(instructor|isc|tutor)', 'userid'], stdout=subprocess.PIPE).stdout.readlines()]


#ISC id
ISCid = subprocess.Popen([CL_INFO_PATH, 'type', 'isc', 'userid'],stdout=subprocess.PIPE).stdout.readlines()[0].strip("\n")
# ISC Name
ISC = getName(ISCid)


ERROR_TEXT = "<p>If you are enrolled in the course, please contact <a href='mailto:%s@student.cs.uwaterloo.ca'>course personnel</a> and we'll get things straightened out.</p>"%Course
MARK_FILE = "/u/%s/marks/public-marks.txt"%Course
PARTICIPATION_MARK_FILE = "/u/%s/marks/public-marks-participation.txt"%Course


form = cgi.FieldStorage()


def normalize(userId):
	return subprocess.Popen([FORMAT_USER_PATH, userId], stdout=subprocess.PIPE).stdout.readlines()[0].strip("\n")

# Do hardcoded normalization that *should* catch most cases...
# Launching external userid-processing utility appears to be *VERRRRY* slow, so
# don't do it when it's clearly good not to.
# Ideally the external launch would just be quicker...
def normalize_quick(userId):
	return userId[:8].lower()

def currentUserId():
        try:
                user = os.environ['REMOTE_USER']
                if user in ROOT_USERS and form.has_key('user'):
                        user = form['user'].value
                if re.match("^[a-zA-Z][a-zA-Z0-9_-]*$", user) == None:
                    return None
                return normalize(user)
        except:
                return None


def getMarksHtml(userId):
        html = ""

	# Open the file in a mode that will accept newline standards for any OS.
	# Then, strip leading newlines from every line to accomodate variations
	# in spreadsheet styling.
        fObj = file(MARK_FILE,"rU")
        lines = [line.lstrip(",") for line in fObj.readlines()]
        fObj.close()

	# TODO:
	# A first line will be inserted containing the heading for the table.
	# The second line will actually be the meanings (implying number) of
	# special lines (here, hardcoded as assigns and totals).  
	# Then, the following N-1 lines will be the hardcoded vales for those
	# table columns; the final column will be student-specific data.
	# PROBLEM: Clicker data will actually be messy here, because there will
	# be *multiple* student-supplied fields.
	# Make it K+M headings, where K are hard-coded, and M are student-specific,
	# separated by a sub-delimiter?
	# ... Oy. :S
        assert( len(lines) > 0 )
        assigns = lines[0].split(",")
        totals = lines[1].split(",")
        
        foundStudent = False

        if I_clicker:
                fObjP = file(PARTICIPATION_MARK_FILE)
                linesP = fObjP.readlines()
                fObjP.close()
                assert( len(linesP) > 0)
                


                for line in linesP[2:]:
                        if normalize_quick(line.split(":")[0]) == userId:
                                marks = line.split(":")[1:]
                                html += "<h4>Clicker marks</h4>\n<table width='40%' border='1'>\n\t<tr>\n\t\t<th>Correct</th>\n\t\t<th>Answered</th>\n\t\t<th>Unanswered</th>\n\t</tr>\n"
                                html += "\t<tr>\n\t\t<td align='center'>%s</td>\n\t\t<td align='center'>%s</td>\n\t\t<td align='center'>%s</td>\n\t</tr>\n" % (marks[1], marks[2], marks[3])
                                html += "</table>\n"
                                html += "<h4>Other marks</h4>\n"
                                foundStudent = True
                                break
                        
        
        for line in lines[2:]:
                if normalize_quick(line.split(",")[0]) == userId:
                        marks = line.split(",")[1:]
                        html += "<table width='40%' border='1'>\n\t<tr>\n\t\t<th>Component</th>\n\t\t<th>Out of</th>\n\t\t<th>Your Grade</th>\n\t</tr>\n"
                        for i in range( len(marks) ):
                                if not(totals[i]==''):
                                        html += "\t<tr>\n\t\t<td align='center'>%s</td>\n\t\t<td align='center'>%s</td>\n\t\t<td align='center'>%s</td>\n\t</tr>\n" % (assigns[i], totals[i], marks[i])
                        html += "</table>\n"

                        foundStudent = True
                        break

        if not foundStudent:
                html = ""
                html += "<p>Oops!  We don't have any marks on record for you.</p>"
                html += ERROR_TEXT

        return html

def getSpecificContents(url):
   try:
        fObj = urllib2.urlopen(url)
        data = "".join(fObj.readlines())
        fObj.close()
        return data
   except:
        return ""

def getPageContents(baseurl):
   return getSpecificContents(baseurl + ".php") or getSpecificContents(baseurl + ".shtml");

def getTopHtml():
        html = ""
        html += "Status: 200 OK\n"
        html += "Content-Type: text/html\n\n"

        html += """<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN"
        "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
        <html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en">
        <head>
        <title>%s: View Marks</title>
        """%Course
        html += getPageContents("http://www.student.cs.uwaterloo.ca/~%s/standard_style"%Course)
        html += """</head>
        <body>"""
        html += getPageContents("http://www.student.cs.uwaterloo.ca/~%s/standard_init"%Course)
        
        html += "<h2 class ='title'>Marks</h2>"
        
        return html

def getBottomHtml():
        html = ""

        html += getPageContents("http://www.student.cs.uwaterloo.ca/~%s/standard_fini"%Course)

        html += """</body>
        </html>
        """
        return html
        
print getTopHtml()

if currentUserId() is None or len(currentUserId()) == 0:
        print "<p>Your username wasn't recognized.</p>"
        print ERROR_TEXT
else:
        fullName = getName(currentUserId())
        if fullName is None:
                fullName = currentUserId()
        else:
                fullName = "%s (%s)" % (fullName, currentUserId())
        

        print "<p>Here are the marks we have recorded for you so far.</p>"

        print "<h3>Marks for %s</h3>" % fullName 
        print getMarksHtml(currentUserId())

        print "<h3>A few notes</h3>"
        print "<ul>\n\t<li>Please contact <a href=\"mailto:%s@student.cs.uwaterloo.ca\">a tutor</a> if your grades are recorded incorrectly.</li>"%Course
        print "\t<li>A mark of 'x' indicates that you are exempt from that component.</li>"
        print "\t<li>You must pass the weighted average of the exams (midterm and final exam) to pass the course.  Refer to the <a href='/~%s/CourseInfo/CourseGrade.shtml'>Grading</a> page for more details.</li>"%Course
        print "\t<li>A mark of UR indicates that a grade is \"under review\" and has yet to be resolved, usually because a component of a student's mark is under investigation for irregularities. Contact the ISC, <a href=\"mailto:%s@cs.uwaterloo.ca\">%s</a>, if you have questions about a UR grade.</li>"%(ISCid,ISC)
        print "\t<li>The marks listed here are \"unofficial\". \"Official\" course marks will be issued by the Registrar.</li>\n</ul>"

print getBottomHtml()