import base64
import http
import json

from twisted.protocols.basic import LineReceiver
from twisted.internet import defer
from util import PappyException

"""
comm.py
Handles creating a listening server bound to localhost that other processes can
use to interact with the proxy.
"""

comm_port = 0
debug = True

def set_comm_port(port):
    global comm_port
    comm_port = port

class CommServer(LineReceiver):

    def __init__(self):
        self.delimiter = '\n'
        self.action_handlers = {
            'ping': self.action_ping,
            'get_request': self.action_get_request,
            'get_response': self.action_get_response,
            'submit': self.action_submit_request,
        }

    def lineReceived(self, line):
        if line == '':
            return
        try:
            command_data = json.loads(line)
            command = command_data['action']
            valid = False
            if command in self.action_handlers:
                valid = True
                result = {'success': True}
                func_defer = self.action_handlers[command](command_data)
                func_defer.addCallback(self.action_result_handler, result)
                func_defer.addErrback(self.action_error_handler, result)
            if not valid:
                raise PappyException('%s is an invalid command' % command_data['action'])
        except PappyException as e:
            return_data = {'success': False, 'message': str(e)}
            self.sendLine(json.dumps(return_data))

    def action_result_handler(self, data, result):
        result.update(data)
        self.sendLine(json.dumps(result))

    def action_error_handler(self, error, result):
        if debug:
            print error.getTraceback()
            return_data = {'success': False, 'message': 'Debug mode enabled, traceback on main terminal'}
        else:
            return_data = {'success': False, 'message': str(error.getErrorMessage())}
            result.update(result)
            self.sendLine(json.dumps(return_data))
            error.trap(Exception)
        return True

    def action_ping(self, data):
        return defer.succeed({'ping': 'pong'})

    @defer.inlineCallbacks
    def action_get_request(self, data):
        try:
            reqid = int(data['reqid'])
        except KeyError:
            raise PappyException("Request with given ID does not exist")

        req = yield http.Request.load_request(reqid)
        dat = json.loads(req.to_json())
        defer.returnValue(dat)

    @defer.inlineCallbacks
    def action_get_response(self, data):
        try:
            reqid = int(data['reqid'])
        except KeyError:
            raise PappyException("Request with given ID does not exist, cannot fetch associated response.")

        req = yield http.Request.load_request(reqid)
        rsp = yield http.Response.load_response(req.response.rspid)
        dat = json.loads(rsp.to_json())
        defer.returnValue(dat)

    @defer.inlineCallbacks
    def action_submit_request(self, data):
        try:
            req = http.Request(base64.b64decode(data['full_request']))
        except:
            raise PappyException("Error parsing request")
        req_sub = yield req.submit_self()
        yield req_sub.deep_save()

        retdata = {}
        retdata['request'] = json.loads(req_sub.to_json())
        if req_sub.response:
            retdata['response'] = json.loads(req_sub.response.to_json())
        defer.returnValue(retdata)