package eirb.pg203;

import org.json.JSONArray;
import org.json.JSONObject;

import eirb.pg203.WeatherData.Condition;
import eirb.pg203.utils.JSONFetcher;

import java.io.IOException;
import java.net.URI;
import java.net.URL;
import java.time.Instant;
import java.util.ArrayList;

/**
 * WeatherAPI implementation
 */
public class WeatherAPI extends WeatherCachedAPI {
    private final String weatherAPIKey;
		private static final String forecastBaseURL = "https://api.weatherapi.com/v1/forecast.json";

    WeatherAPI(String weatherAPIKey) {
        this.weatherAPIKey = weatherAPIKey;
    }

    private JSONObject fetchWeather(int days, String city) throws IOException {
        URL url = URI.create(
                String.format(forecastBaseURL + "?key=%s&q=%s&days=%d",
                        this.weatherAPIKey,
                        city,
                        days
                )
        ).toURL();

        return JSONFetcher.fetch(url);
    }

	private static WeatherData.Condition getConditionFromString(String str) {
		if (str.toLowerCase().contains("rain"))
			return Condition.RAINY;

		else if (str.toLowerCase().contains("partly"))
			return Condition.PARTIAL;

		else if (str.toLowerCase().contains("cloud"))
			return Condition.CLOUDY;

		return Condition.SUNNY;
	}

	private static WeatherData getWeatherDataFromForecast(JSONObject response, int day, String city) {
        JSONObject forecastDay = response.getJSONObject("forecast").getJSONArray("forecastday").getJSONObject(day);
        JSONArray forecastHour = forecastDay.getJSONArray("hour");
        float temp_c = forecastDay.getJSONObject("day").getFloat("avgtemp_c");

		// Calculates the mean for the day
		float windSpeed = 0;
		float windDirection = 0;
		for (int i = 0 ; i < forecastHour.length() ; ++i)
		{
			windSpeed += forecastHour.getJSONObject(i).getFloat("wind_kph");
			windDirection += forecastHour.getJSONObject(i).getFloat("wind_degree");
		}
		windSpeed /= forecastHour.length();
		windDirection /= forecastHour.length();

		String conditionStr = forecastDay.getJSONObject("day").getJSONObject("condition").getString("text");

        return new WeatherData(
				new City(city),
				Instant.now(),
				temp_c,
				windSpeed,
				windDirection,
				getConditionFromString(conditionStr)
			);
	}

    /**
     * @param day Day, 0 &leq; day &leq; 14
     */
    @Override
    public WeatherData getTemperature(int day, String cityName) throws IOException {
        JSONObject result = fetchWeather(day+1, cityName);
		    return getWeatherDataFromForecast(result, day, cityName);
    }

    @Override
    public WeatherData getTemperature(int day, int hour, String cityName) throws IOException{
        return getTemperature(day, cityName);
    }

    public ArrayList<WeatherData> fetchTemperatures(int days, String cityName) throws IOException {
        JSONObject result = fetchWeather(days, cityName);
        ArrayList<WeatherData> weatherDatas = new ArrayList<>();

        for (int day = 0; day < days; ++day) {
            weatherDatas.add(
              getWeatherDataFromForecast(result, day, cityName)
            );
        }

        return weatherDatas;
    }

    @Override
    public String getAPIName() {
        return "WeatherAPI";
    }
}