#!/usr/bin/python2.5
#
# Copyright 2008 the Melange authors.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#   http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

"""Developer views for editing and examining Documents.
"""

__authors__ = [
  '"Todd Larsen" <tlarsen@google.com>',
  ]


from google.appengine.api import users

from django import forms
from django import http
from django.utils.translation import ugettext_lazy

from soc.logic import models
from soc.logic import out_of_band
from soc.logic import path_link_name
from soc.logic.models import document
from soc.logic.site import id_user

from soc.views import helper
from soc.views import simple
from soc.views.helper import access
from soc.views.user import profile

import soc.models.document
import soc.views.helper.forms
import soc.views.helper.requests
import soc.views.helper.responses
import soc.views.helper.widgets
import soc.views.out_of_band


class EditForm(helper.forms.DbModelForm):
  """Django form displayed when Developer edits a Document.
  """
  doc_key_name = forms.fields.CharField(widget=forms.HiddenInput)
  content = forms.fields.CharField(widget=helper.widgets.TinyMCE())
  
  class Meta:
    model = soc.models.document.Document
    
    #: list of model fields which will *not* be gathered by the form
    exclude = ['inheritance_line', 'user', 'created', 'modified']
 
  def clean_partial_path(self):
    partial_path = self.cleaned_data.get('partial_path')
    # TODO(tlarsen): combine path and link_name and check for uniqueness
    return partial_path

  def clean_link_name(self):
    link_name = self.cleaned_data.get('link_name')
    # TODO(tlarsen): combine path and link_name and check for uniqueness
    return link_name


DEF_SITE_DOCS_EDIT_TMPL = 'soc/site/docs/edit.html'
DEF_CREATE_NEW_DOC_MSG = ' You can create a new document by visiting the' \
                         ' <a href="/site/docs/edit">Create ' \
                         'a New Document</a> page.'

SUBMIT_MESSAGES = (
 ugettext_lazy('Document saved.'),
)


def getDocForForm(form):
  """Extracts doc fields from a form and creates a new doc from it
  """

  user = users.get_current_user()
  if user:
    email = user.email()
  else:
    email = None

  partial_path = form.cleaned_data.get('partial_path')
  link_name = form.cleaned_data.get('link_name')

  properties = {}
  properties['partial_path'] = partial_path
  properties['link_name'] = link_name
  properties['title'] = form.cleaned_data.get('title')
  properties['short_name'] = form.cleaned_data.get('short_name')
  properties['abstract'] = form.cleaned_data.get('abstract')
  properties['content'] = form.cleaned_data.get('content')
  properties['user'] = models.user.logic.getFromFields(email=email)

  doc = document.logic.updateOrCreateFromFields(properties,
                                                partial_path=partial_path,
                                                link_name=link_name)
  return doc


def edit(request, partial_path=None, link_name=None,
         template=DEF_SITE_DOCS_EDIT_TMPL):
  """View for a Developer to modify the properties of a Document Model entity.

  Args:
    request: the standard django request object
    partial_path: the Document's site-unique "path" extracted from the URL,
      minus the trailing link_name
    link_name: the last portion of the Document's site-unique "path"
      extracted from the URL
    template: the "sibling" template (or a search list of such templates)
      from which to construct the public.html template name (or names)

  Returns:
    A subclass of django.http.HttpResponse which either contains the form to
    be filled out, or a redirect to the correct view in the interface.
  """

  try:
    access.checkIsDeveloper(request)
  except  soc.views.out_of_band.AccessViolationResponse, alt_response:
    return alt_response.response()

# create default template context for use with any templates
  context = helper.responses.getUniversalContext(request)
  logged_in_id = users.get_current_user()

  doc = None  # assume that no Document entity will be found

  path = path_link_name.combinePath([partial_path, link_name])

  # try to fetch Document entity corresponding to path if one exists    
  try:
    if path:
      doc = document.logic.getFromFields(partial_path=partial_path,
                                         link_name=link_name)
  except out_of_band.ErrorResponse, error:
    # show custom 404 page when path doesn't exist in Datastore
    error.message = error.message + DEF_CREATE_NEW_DOC_MSG
    return simple.errorResponse(request, error, template, context)

  if request.method == 'POST':
    form = EditForm(request.POST)

    if form.is_valid():
      doc = getDocForForm(form)
      
      if not doc:
        return http.HttpResponseRedirect('/')

      new_path = path_link_name.combinePath([doc.partial_path, doc.link_name])
        
      # redirect to new /site/docs/edit/new_path?s=0
      # (causes 'Profile saved' message to be displayed)
      return helper.responses.redirectToChangedSuffix(
          request, path, new_path,
          params=profile.SUBMIT_PROFILE_SAVED_PARAMS)
  else: # method == 'GET':
    # try to fetch Document entity corresponding to path if one exists
    if path:
      if doc:
        # is 'Profile saved' parameter present, but referrer was not ourself?
        # (e.g. someone bookmarked the GET that followed the POST submit) 
        if (request.GET.get(profile.SUBMIT_MSG_PARAM_NAME)
            and (not helper.requests.isReferrerSelf(request, suffix=path))):
          # redirect to aggressively remove 'Profile saved' query parameter
          return http.HttpResponseRedirect(request.path)
    
        # referrer was us, so select which submit message to display
        # (may display no message if ?s=0 parameter is not present)
        context['notice'] = (
            helper.requests.getSingleIndexedParamValue(
                request, profile.SUBMIT_MSG_PARAM_NAME,
                values=SUBMIT_MESSAGES))

        # populate form with the existing User entity
        form = EditForm(initial={'doc_key_name': doc.key().name(),
            'title': doc.title, 'partial_path': doc.partial_path,
            'link_name': doc.link_name, 'short_name': doc.short_name,
            'abstract': doc.abstract, 'content': doc.content,
            'user': doc.user})       
      else:
        if request.GET.get(profile.SUBMIT_MSG_PARAM_NAME):
          # redirect to aggressively remove 'Profile saved' query parameter
          return http.HttpResponseRedirect(request.path)
          
        context['lookup_error'] = ugettext_lazy(
            'Document with that path not found.')
        form = EditForm(initial={'link_name': link_name})
    else:  # no link name specified in the URL
      if request.GET.get(profile.SUBMIT_MSG_PARAM_NAME):
        # redirect to aggressively remove 'Profile saved' query parameter
        return http.HttpResponseRedirect(request.path)

      # no link name specified, so start with an empty form
      form = EditForm()

  context.update({'form': form,
                  'existing_doc': doc})

  return helper.responses.respond(request, template, context)


class CreateForm(helper.forms.DbModelForm):
  """Django form displayed when Developer creates a Document.
  """
  content = forms.fields.CharField(widget=helper.widgets.TinyMCE())
  
  class Meta:
    model = soc.models.document.Document
    
    #: list of model fields which will *not* be gathered by the form
    exclude = ['inheritance_line', 'user', 'created', 'modified']
 
  def clean_partial_path(self):
    partial_path = self.cleaned_data.get('partial_path')
    # TODO(tlarsen): combine path and link_name and check for uniqueness
    return partial_path

  def clean_link_name(self):
    link_name = self.cleaned_data.get('link_name')
    # TODO(tlarsen): combine path and link_name and check for uniqueness
    return link_name


DEF_SITE_DOCS_CREATE_TMPL = 'soc/site/docs/edit.html'

def create(request, template=DEF_SITE_DOCS_CREATE_TMPL):
  """View for a Developer to create a new Document entity.

  Args:
    request: the standard django request object
    template: the "sibling" template (or a search list of such templates)
      from which to construct the public.html template name (or names)

  Returns:
    A subclass of django.http.HttpResponse which either contains the form to
    be filled out, or a redirect to the correct view in the interface.
  """

  try:
    access.checkIsDeveloper(request)
  except  soc.views.out_of_band.AccessViolationResponse, alt_response:
    return alt_response.response()

  # create default template context for use with any templates
  context = helper.responses.getUniversalContext(request)
  logged_in_id = users.get_current_user()

  if request.method == 'POST':
    form = CreateForm(request.POST)

    if form.is_valid():
      doc = getDocForForm(form)

      if not doc:
        return http.HttpResponseRedirect('/')

      new_path = path_link_name.combinePath([doc.partial_path, doc.link_name])
        
      # redirect to new /site/docs/edit/new_path?s=0
      # (causes 'Profile saved' message to be displayed)
      return helper.responses.redirectToChangedSuffix(
          request, None, new_path,
          params=profile.SUBMIT_PROFILE_SAVED_PARAMS)
  else: # method == 'GET':
    # no link name specified, so start with an empty form
    form = CreateForm()

  context['form'] = form

  return helper.responses.respond(request, template, context)


def delete(request, partial_path=None, link_name=None,
           template=DEF_SITE_DOCS_EDIT_TMPL):
  """Request handler for a Developer to delete Document Model entity.

  Args:
    request: the standard django request object
    partial_path: the Document's site-unique "path" extracted from the URL,
      minus the trailing link_name
    link_name: the last portion of the Document's site-unique "path"
      extracted from the URL
    template: the "sibling" template (or a search list of such templates)
      from which to construct the public.html template name (or names)

  Returns:
    A subclass of django.http.HttpResponse which redirects 
    to /site/docs/list.
  """

  try:
    access.checkIsDeveloper(request)
  except  soc.views.out_of_band.AccessViolationResponse, alt_response:
    return alt_response.response()

  # create default template context for use with any templates
  context = helper.responses.getUniversalContext(request)

  existing_doc = None
  path = path_link_name.combinePath([partial_path, link_name])

  # try to fetch Document entity corresponding to path if one exists    
  try:
    if path:
      existing_doc = document.logic.getFromFields(partial_path=partial_path,
                                                  link_name=link_name)
  except out_of_band.ErrorResponse, error:
    # show custom 404 page when path doesn't exist in Datastore
    error.message = error.message + DEF_CREATE_NEW_DOC_MSG
    return simple.errorResponse(request, error, template, context)

  if existing_doc:
    document.logic.delete(existing_doc)

  return http.HttpResponseRedirect('/site/docs/list')