#!/usr/bin/env python

import json
import requests
import sys

from json import JSONEncoder
from requests.adapters import HTTPAdapter
from requests.packages.urllib3.util.retry import Retry
from requests.structures import CaseInsensitiveDict

from aman.config.AirportSequencing import AirportSequencing
from aman.config.RunwaySequencing import RunwaySequencing
from aman.config.Server import Server

class InboundEncoder(JSONEncoder):
    def default(self, o):
        pta = str(o.PlannedArrivalTime)
        delimiter = pta.find('.')
        if -1 == delimiter:
            delimiter = pta.find('+')
        return { 'callsign' : o.Callsign, 'runway' : o.PlannedRunway.Name, 'pta' : pta[0:delimiter] }

class WebUI:
    def __init__(self):
        self.Config = None
        self.Aman = None

    def __del__(self):
        self.release()

    def acquire(self, config : Server, aman):
        self.Config = config
        self.Aman = aman

    def release(self):
        return

    def createSession():
        # prepare the session
        session = requests.Session()
        retry = Retry(total=1, read=1, connect=1)
        adapter = HTTPAdapter(max_retries=retry)
        session.mount('http://', adapter)
        session.mount('https://', adapter)
        return session

    def requestConfiguration(self, airport, navData):
        if airport not in navData.Runways:
            return None

        # prepare the HTTP header and session
        headers = CaseInsensitiveDict()
        headers['Accept'] = 'application/json'
        headers['Content-Type'] = 'application/json'
        session = WebUI.createSession()

        url = self.Config.WebUiUrl + self.Config.WebUiConfigurationReceiver
        data = json.dumps({ 'airport': airport }, ensure_ascii=True)

        try:
            response = session.get(url, headers=headers, data=data, timeout=2)
            if 200 != response.status_code:
                return None
        except requests.exceptions.ConnectTimeout:
            return None

        config = json.loads(response.json())

        # WebUI sent the wrong airport
        if config['airport'] != airport or 0 == len(config['activeRunways']):
            return None

        airportConfig = AirportSequencing(airport)
        airportConfig.UseMustShallMay = config['useMustShallMay']

        # build the sequencing information per runway
        for activeRunway in config['activeRunways']:
            gngRunway = None
            for runway in navData.Runways[airport]:
                if runway.Name == activeRunway['runway']:
                    gngRunway = runway
                    break

            # could not find the runway
            if None == gngRunway:
                return None

            runway = RunwaySequencing(gngRunway)
            runway.Spacing = int(activeRunway['spacing'])
            airportConfig.activateRunway(runway)

        # resolve the dependencies
        for dependency in config['dependentRunways']:
            if 2 == len(dependency):
                airportConfig.addDependency(dependency[0], dependency[1])

        return airportConfig

    def sendSequence(self, airport, inbounds):
        # prepare the HTTP header and session
        headers = CaseInsensitiveDict()
        headers['Accept'] = 'application/json'
        headers['Content-Type'] = 'application/json'
        session = WebUI.createSession()

        # prepare the relevant information
        url = self.Config.WebUiUrl + self.Config.WebUiSequenceNotification
        data = json.dumps({ 'airport': airport, 'sequence': inbounds }, ensure_ascii=True, cls=InboundEncoder)

        # send to the server
        try:
            session.patch(url, headers=headers, data=data, timeout=2)
        except requests.exceptions.ConnectTimeout:
            return