#!/usr/bin/python2
# -*- coding: utf-8 -*-

import magic, os, sys

from fit import Fit
from flask import Flask, render_template, request, flash, redirect, url_for
from flask.ext.wtf import Form, TextField, FileField, SelectField,\
                    validators, ValidationError
from werkzeug import secure_filename
from datetime import date


# set default encoding to utf-8, otherwise pygit2 can not handle umlauts
reload(sys)
sys.setdefaultencoding('utf-8')

app = Flask(__name__)
app.config.from_pyfile('settings.py')

# populate Module-List
fit = {}
for i, study in enumerate(app.config['STUDIES'].items()):
  abbr = study[0]
  fit[abbr] = Fit(os.path.join('static','studies',abbr + '.git'))

  modules = app.config['STUDIES'][study[0]]
  # extend module list with git values
  for module in fit[abbr].get_modules():
    # check if module is already listed
    if all(map(lambda (k,v): v != module, modules)):
      slug = module.decode('ascii', errors='ignore')
      app.config['STUDIES'][study[0]].append((slug, module))

class UploadForm(Form):
    """ Upload Form class for validation """
    study = TextField('Studiengang')
    exam   = FileField('Klausur')
    module = SelectField('Kurs')
    module_new = TextField('Modulname', validators=[validators.Optional(),
    validators.Length(min=5)])
    year   = SelectField(
                'Jahr',
                validators=[validators.Required()],
                choices = [ (str(x),x) for x in 
                  xrange(date.today().year, app.config['FORM_START_YEAR']-1, -1)
                ]
           )

    def validate_exam(form, field):
      exts = app.config['ALLOWED_EXTENSIONS']
      ext = map(field.data.filename.endswith, exts)

      if not any(ext):
        raise ValidationError(u'Ungültiger Dateityp')

      if field.data.content_length > app.config['MAX_CONTENT_LENGTH']:
        raise ValidationError(u'Zu große Datei')
    
    def validate_module(form, field):
      modules = dict(app.config['STUDIES'][form.study.data])
      data = form.module.data
      if data not in modules or data == '':
        raise ValidationError(u'Bitte wähle ein Modul!')




@app.route('/<study>/upload/', methods=['GET', 'POST'])
@app.route('/<study>/upload/<module>', methods=['GET', 'POST'])
def upload(study, module = None):
  form = UploadForm()
  form.study.data = study

  form.module.choices = app.config['STUDIES'][study]
  if 'new' not in dict(form.module.choices):
    form.module.choices.append(('', u'---'))
    form.module.choices.append(('new', u'neues Modul hinzufügen'))


  if form.validate_on_submit():
      if form.module.data == 'new':
        module = form.module_new.data
        slug = module.encode('ascii', errors='ignore')
        i = len(app.config['STUDIES'][study]) - 2
        app.config['STUDIES'][study].insert(i, (slug,module))
      else:
        module = dict(app.config['STUDIES'][study])[form.module.data]

      year = form.year.data
      filename = secure_filename(form.exam.data.filename)
      path = os.path.join(module,year,filename)

      try:
        oid =  fit[study].add_file(form.exam.data.stream.getvalue(), path)
      except:
        oid =  fit[study].add_file(form.exam.data.stream.read(), path)

      flash("Datei %s gespeichert." % filename)

      return redirect(url_for('study_index', study = study, module = module))

  try: form.module.data = [k for (k,v) in form.module.choices if v == module][0]
  except: pass

  return render_template('upload.html',
                            study = study, form = form, module=module)



@app.route('/<study>/files/<oid>/<filename>')
def study_show(study, oid, filename):
  data = fit[study].get_file(oid)
  mime = magic.Magic(mime=True)
  header = { 'Content-Type' : mime.from_buffer(data[:1024]) }
  return data, 200, header



@app.route('/<study>/modules/')
@app.route('/<study>/modules/<module>')
def study_index(study, module=None):
  if module:
    entries = sorted(fit[study].get_module(module), reverse=True)
    return render_template('module_show.html',
              study = study, module=module, entries=entries
           )

  modules = fit[study].get_modules()
  return render_template('module_list.html', study = study, modules=modules)



@app.route('/')
def index():
  get_img_path = lambda x: os.path.join('images', x +'.png')
  studies = [(name,get_img_path(name)) for name,m in app.config['STUDIES'].items()]

  return render_template(
            'index.html',
            studies = studies
         )



@app.route('/403')
@app.errorhandler(403)
def forbidden():
  return render_template('403.html')



if __name__ == "__main__":
    app.run()