from flask import Flask
from flask import abort, redirect, url_for
import sys, os
sys.path.append("./lib")
from Pb import *
from Server.InvalidUsage import InvalidUsage

class Server(object):
  def __init__(self):
    self.app = Flask(__name__)
    @self.app.route('/im/pb/<pb_classname>', methods=['POST'])
    def pb():
      self._response_post(pb_classname, request)

    @self.app.errorhandler(InvalidUsage)
    def handle_invalid_usage(error):
        response = jsonify(error.to_dict())
        response.status_code = error.status_code
        return response

    self._classname_aliases = {
      'generate' : 'PbGenerate', 
      'imgrid' : 'PbGrid',
    }
  def _find_class_by_name(self, pb_classname):
    pb_classname = self._classname_aliases.get(pb_classname, None) or pb_classname
    try:
      filter(lambda c: c.__name__ == pb_classname, Pb.__subclasses__())[0]
    except IndexError:
      raise InvalidUsage('No such api', status_code=410)

  def _response_post(self, pb_classname, request):
    pb_class = self._find_class_by_name(pb_classname)
    classnames = map(lambda c: c.__name__, Pb.__subclasses__())
    try:
        im = pb_class(**(dict(request.forms)))
        im.create();
        return im.file_json();
    #FIXME handle BadParamsError and PbError separately
    except Exception as e:
        sys.stderr.write("%s failure" % pb_class.__name__)
        sys.stderr.write("params:\n")
        for i in request.forms:
            sys.stderr.write("{}:{}\n".format(i, request.forms[i]))
        raise;
        return json.dumps({ 'error' : 'Request could not be processed' })

  def run(self):
    self.app.run()