import json
# this is for django objects only
#from django.core import serializers
from django.http import HttpResponse, HttpResponseForbidden

from engine.manifoldquery import ManifoldQuery
from engine.manifoldapi import ManifoldAPI

# add artificial delay in s
debug_spin=0
#debug_spin=1

# this view is what the javascript talks to when it sends a query
# see also
# myslice/urls.py
# as well as 
# static/js/manifold-async.js
def api (request,format):
    """the view associated with /manifold/api/ 
with the query passed using POST"""
    
    # expecting a POST
    if request.method != 'POST':
        print "manifoldproxy.api: unexpected method %s -- exiting"%request.method
        return 
    # we only support json for now
    # if needed in the future we should probably cater for
    # format_in : how is the query encoded in POST
    # format_out: how to serve the results
    if format != 'json':
        print "manifoldproxy.api: unexpected format %s -- exiting"%format
        return
    # translate incoming POST request into a query object
    manifold_query = ManifoldQuery()
    manifold_query.fill_from_dict(request.POST)
    # retrieve session for request
    manifold_api_session_auth = request.session['manifold']['auth']
    # actually forward
    manifold_api= ManifoldAPI(auth=manifold_api_session_auth)
    answer=manifold_api.send_manifold_query (manifold_query)
    if debug_spin:
        import time
        time.sleep(debug_spin)
    # return json-encoded answer
    return HttpResponse (json.dumps(answer), mimetype="application/json")

#################### 
# see CSRF_FAILURE_VIEW in settings.py
# the purpose of redefining this was to display the failure reason somehow
# this however turns out disappointing/not very informative
failure_answer=[ "csrf_failure" ]
def csrf_failure(request, reason=""):
    print "CSRF failure with reason '%s'"%reason
    return HttpResponseForbidden (json.dumps (failure_answer), mimetype="application/json")