//
//  LocalWeatherConditions.swift
//  Meshtastic
//
//  Created by Garth Vander Houwen on 7/9/24.
//
import SwiftUI
import MapKit
import WeatherKit
import OSLog

struct LocalWeatherConditions: View {
	private let gridItemLayout = Array(repeating: GridItem(.flexible(), spacing: 10), count: 2)
	@State var location: CLLocation?
	/// Weather
	/// The current weather condition for the city.
	@State private var condition: WeatherCondition?
	@State private var temperature: String = ""
	@State private var dewPoint: String = ""
	@State private var humidity: Int?
	@State private var pressure: Measurement<UnitPressure>?
	@State private var windSpeed: String = ""
	@State private var windGust: String = ""
	@State private var windDirection: Measurement<UnitAngle>?
	@State private var windCompassDirection: String = ""
	@State private var symbolName: String = "cloud.fill"
	@State private var attributionLink: URL?
	@State private var attributionLogo: URL?

	@Environment(\.colorScheme) var colorScheme: ColorScheme
	var body: some View {
		if location != nil {
			VStack {
				LazyVGrid(columns: gridItemLayout) {
					WeatherConditionsCompactWidget(temperature: temperature, symbolName: symbolName, description: condition?.description.uppercased() ?? "??")
					HumidityCompactWidget(humidity: humidity ?? 0, dewPoint: dewPoint)
					PressureCompactWidget(pressure: String(pressure?.value ?? 0.0 / 100), unit: pressure?.unit.symbol ?? "??", low: pressure?.value ?? 0.0 <= 1009.144)
					WindCompactWidget(speed: windSpeed, gust: windGust, direction: windCompassDirection)
				}
			}
			.padding(.top)
			.task {
				do {
					if location != nil {
						let weather = try await WeatherService.shared.weather(for: location!)
						let numFormatter = NumberFormatter()
						let measurementFormatter = MeasurementFormatter()
						numFormatter.maximumFractionDigits = 0
						measurementFormatter.numberFormatter = numFormatter
						measurementFormatter.unitStyle = .short
						measurementFormatter.locale = Locale.current
						condition = weather.currentWeather.condition
						temperature = measurementFormatter.string(from: weather.currentWeather.temperature)
						dewPoint = measurementFormatter.string(from: weather.currentWeather.dewPoint)
						humidity = Int(weather.currentWeather.humidity * 100)
						pressure = weather.currentWeather.pressure
						windSpeed = measurementFormatter.string(from: weather.currentWeather.wind.speed)
						windGust = measurementFormatter.string(from: weather.currentWeather.wind.gust ?? Measurement(value: 0.0, unit: weather.currentWeather.wind.gust!.unit))
						windDirection = weather.currentWeather.wind.direction
						windCompassDirection = weather.currentWeather.wind.compassDirection.description
						symbolName = weather.currentWeather.symbolName
						let attribution = try await WeatherService.shared.attribution
						attributionLink = attribution.legalPageURL
						attributionLogo = colorScheme == .light ? attribution.combinedMarkLightURL : attribution.combinedMarkDarkURL
					}
				} catch {
					Logger.services.error("Could not gather weather information: \(error.localizedDescription)")
					condition = .clear
					symbolName = "cloud.fill"
				}
			}
			VStack {
				HStack {
					AsyncImage(url: attributionLogo) { image in
						image
							.resizable()
							.scaledToFit()
					} placeholder: {
						ProgressView()
							.controlSize(.mini)
					}
					.frame(height: 10)
					Link("Other data sources", destination: attributionLink ?? URL(string: "https://weather-data.apple.com/legal-attribution.html")!)
						.font(.caption2)
				}
				.padding(2)
			}
		}
	}
}

/// Magnus Formula
func calculateDewPoint(temp: Float, relativeHumidity: Float) -> Double {
	let a: Float = 17.27
	let b: Float = 237.7
	let alpha = ((a * temp) / (b + temp)) + log(relativeHumidity / 100.0)
	let dewPoint = (b * alpha) / (a - alpha)
	let dewPointUnit = Measurement<UnitTemperature>(value: Double(dewPoint), unit: .celsius)
	let locale = NSLocale.current as NSLocale
	let localeUnit = locale.object(forKey: NSLocale.Key(rawValue: "kCFLocaleTemperatureUnitKey"))
	var format: UnitTemperature = .celsius

	if localeUnit! as? String == "Fahrenheit" {
		format = .fahrenheit
	}
	return dewPointUnit.converted(to: format).value
}