@page "/validation"
@using BlazorIntro.Data
@using C1.Blazor.Core
@using C1.Blazor.Input
@using C1.Blazor.Grid
@using C1.DataCollection
@inject IJSRuntime JsRuntime
@inject WeatherForecastService ForecastService
<h1>FlexGrid Validation</h1>
<FlexGrid @ref="grid" AutoGenerateColumns="false" ItemsSource="forecasts"  CellEditEnding="OnCellEditEnding" >
     <FlexGridColumns>
         <GridColumn Header="Date" Binding="Date" Format="d"></GridColumn>
        <GridColumn Header="Temp C" Binding="TemperatureC" Format="n2"></GridColumn>
         <GridColumn Header="Temp F" Binding="TemperatureF"></GridColumn>
         <GridColumn Header="Summary" Binding="Summary"></GridColumn>
     </FlexGridColumns>
 </FlexGrid>
 @code {
     WeatherForecast[] forecasts;
     protected override async Task OnInitializedAsync()
     {
         forecasts = await ForecastService.GetForecastAsync(DateTime.Now);
     }
     public FlexGrid grid;
     protected void OnCellEditEnding(object sender, GridCellEditEventArgs e)
     {
         var _originalValue = grid[e.CellRange.Row, e.CellRange.Column];
         int value;
         Int32.TryParse(((C1TextBox)grid.ActiveEditor).Text, out value);
         ValidationMessage _res = isValidValue(value, grid.Columns[e.CellRange.Column].Binding);
         if (_res != null && !(bool)_res.isVal)
         {
             e.Cancel = true;
             DisplayAlert(_res.Message);
             (grid.ActiveEditor as C1TextBox).Text = _originalValue.ToString();
         }
     }
    private ValidationMessage isValidValue(object value, string prop)
     {
        if (prop == "TemperatureC" && ((int)value < 20 || (int)value > 55))
         {
             return new ValidationMessage() { isVal = false, Message = "Value should be between 20 and 55!" };
         }
         return new ValidationMessage() { isVal = true };
     }
    class ValidationMessage
     {
         public bool isVal { get; set; }
         public string? Message { get; set; }
     }
    private Task<bool> DisplayAlert(string message)
     {
         return JsRuntime.InvokeAsync<bool>("alert", message).AsTask();
     }
 }