using Microsoft.Maui.Storage;
using System.Globalization;
using System.Text.Json;

namespace MauiWeather;

public partial class MainPage : ContentPage
{
    private static readonly HttpClient Client = new()
    {
        Timeout = TimeSpan.FromSeconds(15)
    };

    private readonly (string Name, double Lat, double Lon)[] cities =
    [
        ("Kuala Lumpur", 3.1390, 101.6869),
        ("Singapore", 1.3521, 103.8198),
        ("Tokyo", 35.6762, 139.6503),
        ("London", 51.5072, -0.1276)
    ];

    public MainPage()
    {
        InitializeComponent();
        CityPicker.ItemsSource = cities.Select(c => c.Name).ToList();
        int saved = Preferences.Default.Get("cityIndex", 0);
        CityPicker.SelectedIndex = Math.Clamp(saved, 0, cities.Length - 1);
    }

    private async void OnRefreshClicked(object sender, EventArgs e)
    {
        int index = CityPicker.SelectedIndex;
        if (index < 0) return;
        Preferences.Default.Set("cityIndex", index);
        var city = cities[index];

        string lat = city.Lat.ToString(CultureInfo.InvariantCulture);
        string lon = city.Lon.ToString(CultureInfo.InvariantCulture);
        string url = "https://api.open-meteo.com/v1/forecast" +
            $"?latitude={lat}&longitude={lon}" +
            "&current=temperature_2m,relative_humidity_2m,wind_speed_10m";

        RefreshButton.IsEnabled = false;
        StatusLabel.Text = $"Loading {city.Name}...";
        try
        {
            using var response = await Client.GetAsync(url);
            response.EnsureSuccessStatusCode();
            string jsonText = await response.Content.ReadAsStringAsync();
            using var doc = JsonDocument.Parse(jsonText);
            var current = doc.RootElement.GetProperty("current");

            double temp = current.GetProperty("temperature_2m").GetDouble();
            double humidity = current.GetProperty("relative_humidity_2m").GetDouble();
            double wind = current.GetProperty("wind_speed_10m").GetDouble();

            TemperatureLabel.Text = $"{temp:0.#} °C";
            HumidityLabel.Text = $"{humidity:0}%";
            WindLabel.Text = $"{wind:0.#} km/h";
            StatusLabel.Text = $"Current conditions for {city.Name}.";
        }
        catch (Exception ex) when (ex is HttpRequestException
                                  or TaskCanceledException
                                  or JsonException
                                  or KeyNotFoundException)
        {
            StatusLabel.Text = "Weather unavailable. Check the connection and try again.";
        }
        finally
        {
            RefreshButton.IsEnabled = true;
        }
    }
}