namespace Htmx.ApiDemo.Templates.Components;

/// <summary>
/// shadcn-style range Calendar. Lets the user pick a start and end date.
/// State and rendering are handled by components.js (initCalendarRange).
/// Fires a <c>rangeChange</c> CustomEvent with <c>{ start, end }</c> detail.
/// </summary>
public sealed class CalendarRange : CalendarRangeBase
{
    private readonly byte[] _idData;
    private readonly byte[] _nameStartData;
    private readonly byte[] _nameEndData;
    private readonly byte[] _yearData;
    private readonly byte[] _monthData;
    private readonly byte[] _defaultStartData;
    private readonly byte[] _defaultEndData;

    public CalendarRange(
        string id,
        string name            = "date",
        DateOnly? selectedStart = null,
        DateOnly? selectedEnd   = null)
    {
        // Show the start month if provided, otherwise today
        var viewDate = selectedStart ?? DateOnly.FromDateTime(DateTime.Today);

        _idData        = id.ToUtf8Bytes();
        _nameStartData = (name + "-start").ToUtf8Bytes();
        _nameEndData   = (name + "-end").ToUtf8Bytes();
        _yearData      = viewDate.Year.ToString().ToUtf8Bytes();
        _monthData     = (viewDate.Month - 1).ToString().ToUtf8Bytes(); // 0-based

        _defaultStartData = selectedStart.HasValue
            ? selectedStart.Value.ToString("yyyy-MM-dd").ToUtf8Bytes()
            : []  ;

        _defaultEndData = selectedEnd.HasValue
            ? selectedEnd.Value.ToString("yyyy-MM-dd").ToUtf8Bytes()
            : [];
    }

    protected override void RenderId(HtmxRenderContext ctx)           => ctx.Writer.WriteUtf8(_idData);
    protected override void RenderNameStart(HtmxRenderContext ctx)    => ctx.Writer.WriteUtf8(_nameStartData);
    protected override void RenderNameEnd(HtmxRenderContext ctx)      => ctx.Writer.WriteUtf8(_nameEndData);
    protected override void RenderYear(HtmxRenderContext ctx)         => ctx.Writer.WriteUtf8(_yearData);
    protected override void RenderMonth(HtmxRenderContext ctx)        => ctx.Writer.WriteUtf8(_monthData);
    protected override void RenderDefaultStart(HtmxRenderContext ctx) => ctx.Writer.WriteUtf8(_defaultStartData);
    protected override void RenderDefaultEnd(HtmxRenderContext ctx)   => ctx.Writer.WriteUtf8(_defaultEndData);
}