#!/usr/bin/python3

import json
import urllib.request
import datetime
import time
import pytz
from string import Template

b = "\x0312"
y = "\x038"

API_URL = "https://fdo.rocketlaunch.live/json/launches/next/1"

class launch(object):
   def api_request(self):
      request = urllib.request.Request(API_URL)
      response = urllib.request.urlopen(request).read()
      json_data = json.loads(response.decode('UTF-8'))
      return json_data['result'][0]

   def rocket_name(self, json_data):
      try:
         name = json_data['vehicle']['name']
      except:
         name = "UNKNOWN"
      return name

   def mission_name(self, json_data):
      try:
         name = json_data['name']
      except:
         name = "UNKNOWN"
      return name

   def net_raw_utc(self, json_data):
      time_utc_string = json_data['t0']
      time_utc = datetime.datetime.fromisoformat(time_utc_string)
      return time_utc


class DeltaTemplate(Template):
    delimiter = "%"


def strfdelta(tdelta, fmt):
    d = {"D": tdelta.days}
    hours, rem = divmod(tdelta.seconds, 3600)
    minutes, seconds = divmod(rem, 60)
    d["H"] = '{:02d}'.format(hours)
    d["M"] = '{:02d}'.format(minutes)
    d["S"] = '{:02d}'.format(seconds)
    t = DeltaTemplate(fmt)
    return t.substitute(**d)


def next_launch():
   l = launch()
   json_data = l.api_request()
   rocket = l.rocket_name(json_data)
   mission = l.mission_name(json_data)
   launch_time = l.net_raw_utc(json_data)
   now = datetime.datetime.now(datetime.timezone.utc).replace(microsecond=0)
   timedelta = abs(launch_time - now)
   t_string = "-" if launch_time > now else "+"
   deltastring = strfdelta(timedelta, "T"+t_string+"%D:%H:%M:%S")
   del l
   return rocket, mission, deltastring