using Robust.Client.AutoGenerated;
using Robust.Client.UserInterface;
using Robust.Client.UserInterface.XAML;

namespace Content.Client.UserInterface.Controls;

/// <summary>
/// An input control for dates.
/// </summary>
[GenerateTypedNameReferences]
public sealed partial class DatePicker : Control
{
    /// <summary>
    /// Raised when <see cref="SelectedDate"> is changed.
    /// </summary>
    public event Action? OnChanged;

    /// <summary>
    /// The date currently selected by the input, or null if it's not a valid date.
    /// </summary>
    public DateOnly? SelectedDate;

    /// <summary>
    /// The oldest possible date that the user can select.
    /// </summary>
    public DateOnly MinDate = DateOnly.MinValue;

    /// <summary>
    /// The most recent date that the user can select.
    /// </summary>
    public DateOnly MaxDate = DateOnly.MaxValue;

    /// <summary>
    /// True if a valid date is selected.
    /// </summary>
    public bool IsValid => SelectedDate is not null;

    public DatePicker()
    {
        RobustXamlLoader.Load(this);

        MonthOptionButton.AddItem(Loc.GetString("datepicker-month"), 0);
        for (var i = 1; i <= 12; i++)
        {
            MonthOptionButton.AddItem(Loc.GetString($"month-{i}"), i);
        }

        DayLineEdit.OnTextChanged += _ => Update();
        YearLineEdit.OnTextChanged += _ => Update();
        MonthOptionButton.OnItemSelected += args => {
            if (args.Id != 0)
            {
                MonthOptionButton.SelectId(args.Id);
            }
            Update();
        };
    }

    private void Update()
    {
        var monthNum = MonthOptionButton.SelectedId;

        DateOnly? newDate = null;

        if (int.TryParse(YearLineEdit.Text, out var year)
            && int.TryParse(DayLineEdit.Text, out var day)
            && monthNum != 0
        )
        {
            newDate = new DateOnly(year, monthNum, day);
        }

        if (newDate < MinDate || newDate > MaxDate)
        {
            newDate = null;
        }

        if (SelectedDate != newDate)
        {
            SelectedDate = newDate;
            OnChanged?.Invoke();
        }
    }
}