from django.http import HttpResponse
from django.template import Context, loader
from djangomako.shortcuts import render_to_response, render_to_string
import json, os, sys
from django.core.context_processors import csrf

from django.template import Context
from django.contrib.auth.models import User
from auth.models import UserProfile
from django.shortcuts import redirect

import StringIO

from django.http import Http404

from models import StudentModule

import urllib

from django.conf import settings

import content_parser

import uuid

from module_render import *

from lxml import etree

etree.set_default_parser(etree.XMLParser(dtd_validation=False, load_dtd=False,
                                         remove_comments = True))

template_imports={'urllib':urllib}

def profile(request):
    ''' User profile. Show username, location, etc, as well as grades .
        We need to allow the user to change some of these settings .'''
    if not request.user.is_authenticated():
        return redirect('/')

    dom=content_parser.course_file(request.user)
    hw=[]
    course = dom.xpath('//course/@name')[0]
    chapters = dom.xpath('//course[@name=$course]/chapter', course=course)

    responses=StudentModule.objects.filter(student=request.user)

    for c in chapters:
        chname=c.get('name')
        for s in dom.xpath('//course[@name=$course]/chapter[@name=$chname]/section', 
                           course=course, chname=chname):
            problems=dom.xpath('//course[@name=$course]/chapter[@name=$chname]/section[@name=$section]//problem', 
                           course=course, chname=chname, section=s.get('name'))
            scores=[]
            if len(problems)>0:
                for p in problems:
                    id = p.get('filename')
                    correct = 0
                    for response in responses:
                        if response.module_id == id:
                            if response.grade!=None:
                                correct=response.grade
                            else:
                                correct=0
                    total=capa_module.LoncapaModule(etree.tostring(p), "id").max_score() # TODO: Add state. Not useful now, but maybe someday problems will have randomized max scores? 
                    scores.append((int(correct),total))
                score={'course':course,
                       'section':s.get("name"),
                       'chapter':c.get("name"),
                       'scores':scores,
                       }
                hw.append(score)

    user_info=UserProfile.objects.get(user=request.user)

    context={'name':user_info.name,
             'username':request.user.username,
             'location':user_info.location,
             'language':user_info.language,
             'email':request.user.email,
             'homeworks':hw, 
             'csrf':csrf(request)['csrf_token']
             }
    return render_to_response('profile.html', context)

def render_accordion(request,course,chapter,section):
    ''' Draws navigation bar. Takes current position in accordion as
        parameter. Returns (initialization_javascript, content)'''
    def format_string(string):
        return urllib.quote(string.replace(' ','_'))

    toc=content_parser.toc_from_xml(content_parser.course_file(request.user), chapter, section)
    active_chapter=1
    for i in range(len(toc)):
        if toc[i]['active']:
            active_chapter=i
    context=dict([['active_chapter',active_chapter],
                  ['toc',toc], 
                  ['course_name',course],
                  ['format_string',format_string],
                  ['csrf',csrf(request)['csrf_token']]] + \
                     template_imports.items())
    return {'init_js':render_to_string('accordion_init.js',context), 
            'content':render_to_string('accordion.html',context)}

def index(request, course="6.002 Spring 2012", chapter="Using the System", section="Hints"): 
    ''' Displays courseware accordion, and any associated content. 
    ''' 
    if not settings.COURSEWARE_ENABLED or not request.user.is_authenticated():
        return redirect('/')

    # Fixes URLs -- we don't get funny encoding characters from spaces
    # so they remain readable
    ## TODO: Properly replace underscores
    course=course.replace("_"," ")
    chapter=chapter.replace("_"," ")
    section=section.replace("_"," ")

    # HACK: Force course to 6.002 for now
    # Without this, URLs break
    if course!="6.002 Spring 2012":
        return redirect('/')

    dom = content_parser.course_file(request.user)
    dom_module = dom.xpath("//course[@name=$course]/chapter[@name=$chapter]//section[@name=$section]/*[1]", 
                           course=course, chapter=chapter, section=section)
    if len(dom_module) == 0:
        module = None
    else:
        module = dom_module[0]

    accordion=render_accordion(request, course, chapter, section)

    module=render_module(request, module)

    if 'init_js' not in module:
        module['init_js']=''

    

    context={'init':accordion['init_js']+module['init_js'],
             'accordion':accordion['content'],
             'content':module['content'],
             'csrf':csrf(request)['csrf_token']}
    return render_to_response('courseware.html', context)