@namespace WtmBlazorUtils
@inherits WTComponent
@inject WtmBlazorContext WtmBlazor
@using System.Linq.Expressions;

<DateTimeRange @ref="dt" Value="innerValue" OnConfirm="SetDate" OnClearValue="SetDate" DisplayText="@LabelText"/>

@code{

    [Parameter]
    public DateRange Value { get; set; }
    [Parameter]
    public EventCallback<DateRange> ValueChanged { get; set; }
    [Parameter]
    public Expression<Func<DateRange>> ValueExpression { get; set; }
    private DateTimeRangeValue innerValue = new DateTimeRangeValue();

    [Parameter]
    public string LabelText { get; set; }

    private DateTimeRange dt { get; set; }

    protected DateRange CurrentValue
    {
        get => Value;
        set
        {
            var hasChanged = !EqualityComparer<DateRange>.Default.Equals(value, Value);
            if (hasChanged)
            {
                Value = value;
                _ = ValueChanged.InvokeAsync(value);
            }
        }
    }

    protected override Task OnInitializedAsync()
    {
        if (string.IsNullOrEmpty(LabelText))
        {
            LabelText = ValueExpression.GetPropertyDisplayName(WtmBlazor.Localizer);
        }
        return base.OnInitializedAsync();
    }

    protected override Task OnParametersSetAsync()
    {
        if (Value != null && Value.GetStartTime() != null && Value.GetEndTime() != null) {
            innerValue = new DateTimeRangeValue { Start = Value.GetStartTime().Value, End = Value.GetEndTime().Value };
        }
        else
        {
            innerValue = new DateTimeRangeValue();
        }
        return base.OnParametersSetAsync();
    }

    private Task SetDate(DateTimeRangeValue v)
    {
        if (v.Start == DateTime.MinValue && v.End == DateTime.MinValue)
        {
            CurrentValue = null;
        }
        else
        {
            CurrentValue = new DateRange(v.Start, v.End);
        }
        return Task.FromResult(CurrentValue);
    }

}