import json
import requests
import re
import datetime
import dateutil.parser as dp


class NoDefaultLocation(Exception):
    def __init__(self, message=None):
        default_message = "No default location set"

        if not message:
            message = default_message

        super().__init__(message)


class NoLocationSpecified(Exception):
    def __init__(self, message=None):
        default_message = "No location specified"

        if not message:
            message = default_message

        super().__init__(message)


class WeatherApi:

    def __init__(self, nick):
        self.nick = nick
        self.weather_api_url = "https://api.weatherapi.com/v1"
        self.api_key_filename = "./weather_api_key.txt"
        self.user_preferences_filename = "./weather_user_preferences.json"
        self.read_api_key()

        self.unit_suffices = {
                'metric': {
                    'temp': 'c',
                    'rate': 'kph',
                    'volume': 'mm',
                    'baro': 'mb',
                    'distance': 'km'
                },
                'imperial': {
                    'temp': 'f',
                    'rate': 'mph',
                    'volume': 'in',
                    'baro': 'in',
                    'distance': 'miles'
                }
        }

    def read_api_key(self):
        with open(self.api_key_filename) as fp:
            api_key = fp.read()
        self.api_key = api_key.strip()

    def get_user_preferences(self, nick):
        try:
            with open(self.user_preferences_filename) as fp:
                user_preferences = json.load(fp)
        except FileNotFoundError:
            user_preferences = {
                    nick: {
                        'location': None,
                        'units': 'metric'
                    },
            }
        except KeyError:
            user_preferences[nick] = {
                    'location': None,
                    'units': 'metric'
            }

        return user_preferences

    def set_user_preferences(self, nick, location=None, units=None):
        user_preferences = self.get_user_preferences(nick)

        # Only acceptable units are 'imperial' or 'metric' (no kelvin for now)
        if not units or (units and units not in ['metric', 'imperial']):
            units = 'metric'

        try:
            user_preferences[nick]['units'] = units

            if location:
                user_preferences[nick]['location'] = location

        except KeyError:
            user_preferences[nick] = {
                    'location': location,
                    'units': units
            }

        with open(self.user_preferences_filename, 'w') as fp:
            json.dump(user_preferences, fp)

    def get_current_conditions(self, nick, location=None, units=None):
        user_preferences = self.get_user_preferences(nick)
        units = user_preferences[nick]['units'] if nick in user_preferences.keys() else 'metric'

        if not location:
            location = user_preferences[nick]['location'] if user_preferences[nick]['location'] else raise NoDefaultLocation()

        # URL for current conditions
        current_url = f"{self.weather_api_url}/current.json?key={self.api_key}&q={location}&qai=no"

        # Make the request and get the results
        current_request = requests.get(current_url)
        current_data = current_request.content
        current_json = json.loads(current_data.decode('utf-8'))

        # Different formats for different units
        current = current_json['current']
        location = current_json['location']

        current_output_location = f"{location['name']}, {location['region']}, {location['country']}"

        temp = current[f"temp_{self.unit_suffices[units]['temp']}"]
        wind_speed = current[f"wind_{self.unit_suffices[units]['rate']}"]

        current_output_format = f"{current_output_location} | {temp}°{self.unit_suffices[units]['temp'].upper()} | {current['humidity']}% | {current['condition']['text']} | {current['wind_dir']} {current['wind_degree']}° {wind_speed} {self.unit_suffices[units]['rate']}" 

        return current_output_format

    def get_forecast(self, nick, location=None, days=5, units=None):
        user_preferences = self.get_user_preferences(nick) if not units else 'metric'
        units = user_preferences[nick]['units'] if nick in user_preferences.keys() else 'metric'

        if not location:
            location = user_preferences[nick]['location']


        # URL for forecast
        forecast_url = f"{self.weather_api_url}/forecast.json?key={self.api_key}&q={location}&days={days}&qai=no"

        # Make the request and get the results
        forecast_request = requests.get(forecast_url)
        forecast_data = forecast_request.content
        forecast_json = json.loads(forecast_data.decode('utf-8'))
        location = forecast_json['location']
        forecast = forecast_json['forecast']['forecastday']

        # Find the highest and lowest temperature over each 24 hour period
        forecast_temps = []

        for day in forecast_json['forecast']['forecastday']:
            # Set the initial high and low values to absurd values
            daily_temp_range = {
                    'day': day['date'],
                    'day_of_week': datetime.datetime.strftime(dp.parse(day['date']), '%a'),
                    'high': -10000.0,
                    'low': 10000.0,
                    'conditions': ''
            }

            for hour in day['hour']:
                temp = hour[f"temp_{self.unit_suffices[units]['temp']}"]

                if temp >= daily_temp_range['high']:
                    daily_temp_range['high'] = temp
                    # We only want the conditions for when the temp is the highest
                    daily_temp_range['conditions'] = hour['condition']['text']

                if temp < daily_temp_range['low']:
                    daily_temp_range['low'] = temp

            forecast_temps.append(daily_temp_range)

        # Different formats for different units
        forecast_output_location = f"{location['name']}, {location['region']}, {location['country']}"
        forecast_days = ""

        for forecast_temp in forecast_temps:
            forecast_days += f" | {forecast_temp['day_of_week']} - {forecast_temp['high']}°{self.unit_suffices[units]['temp'].upper()}/{forecast_temp['low']}°{self.unit_suffices[units]['temp'].upper()} - {forecast_temp['conditions']}"

        forecast_output_format = f"{forecast_output_location}{forecast_days}"

        return forecast_output_format