namespace Htmx.ApiDemo.Templates.Components;

/// <summary>
/// shadcn-style Calendar (date-picker) component driven entirely by HyperScript.
/// Pass a selected date to pre-highlight a day; defaults to today.
/// </summary>
public sealed class Calendar : CalendarBase
{
    private readonly byte[] _idData;
    private readonly byte[] _nameData;
    private readonly byte[] _yearData;
    private readonly byte[] _monthData;           // 0-based JS month
    private readonly byte[] _selectedDayData;
    private readonly byte[] _selectedMonthData;   // 0-based
    private readonly byte[] _selectedYearData;
    private readonly byte[] _defaultValueData;

    public Calendar(
        string id,
        string name          = "date",
        DateOnly? selected   = null)
    {
        var date = selected ?? DateOnly.FromDateTime(DateTime.Today);

        _idData           = id.ToUtf8Bytes();
        _nameData         = name.ToUtf8Bytes();
        _yearData         = date.Year.ToString().ToUtf8Bytes();
        _monthData        = (date.Month - 1).ToString().ToUtf8Bytes();   // JS months are 0-based
        _selectedDayData  = date.Day.ToString().ToUtf8Bytes();
        _selectedMonthData= (date.Month - 1).ToString().ToUtf8Bytes();
        _selectedYearData = date.Year.ToString().ToUtf8Bytes();
        _defaultValueData = date.ToString("yyyy-MM-dd").ToUtf8Bytes();
    }

    protected override void RenderId(HtmxRenderContext ctx)            => ctx.Writer.WriteUtf8(_idData);
    protected override void RenderName(HtmxRenderContext ctx)          => ctx.Writer.WriteUtf8(_nameData);
    protected override void RenderYear(HtmxRenderContext ctx)          => ctx.Writer.WriteUtf8(_yearData);
    protected override void RenderMonth(HtmxRenderContext ctx)         => ctx.Writer.WriteUtf8(_monthData);
    protected override void RenderSelectedDay(HtmxRenderContext ctx)   => ctx.Writer.WriteUtf8(_selectedDayData);
    protected override void RenderSelectedMonth(HtmxRenderContext ctx) => ctx.Writer.WriteUtf8(_selectedMonthData);
    protected override void RenderSelectedYear(HtmxRenderContext ctx)  => ctx.Writer.WriteUtf8(_selectedYearData);
    protected override void RenderDefaultValue(HtmxRenderContext ctx)  => ctx.Writer.WriteUtf8(_defaultValueData);
}