FilterBuilder

@* Apply puts the filter in the address, and the page reads it from there. *@
@using Rows = IzzyBlazor.Site.Examples.Table.Orders
@using IzzyBlazor.Site.Examples.Table
@inject NavigationManager Navigation
<Stack Gap="4" Grow>
    <FilterBuilder Fields="_fields" Name="orders-filter" />
    <TextBlock Size="TextSize.Sm" Color="Color.Muted">
        <Code>@(_filter?.ToString() ?? "No filter")</Code>: @Matches.Count of @Rows.All.Count orders
    </TextBlock>
</Stack>

@code {
    private static readonly IReadOnlyList<DataField<Order>> _fields = DataFields.Of<Order>();

    private Filter? _filter;

    private List<Order> Matches => new DataRequest<Order> { Filter = _filter }.ApplyFiltering(Rows.All.AsQueryable(), _fields).ToList();

    protected override void OnInitialized()
    {
        Navigation.LocationChanged += (_, _) => InvokeAsync(() =>
        {
            Read();
            StateHasChanged();
        });
        Read();
    }

    private void Read()
    {
        var query = new Uri(Navigation.Uri).Query;
        var text = Microsoft.AspNetCore.WebUtilities.QueryHelpers.ParseQuery(query).GetValueOrDefault("orders-filter").ToString();
        _filter = Filter.TryParse(text, out var parsed) ? parsed : null;
    }
}