pushy/Pushy.Silo/Grains/TextItemGrain.cs

using Pushy.Domain;

namespace Pushy.Silo.Grains;

public sealed class TextItemGrain : IGrainBase, ITextItem, IRemindable
{
    private readonly IPersistentState<TextItem> _state;
    private readonly ILogger<TextItemGrain> _logger;
    
    private IGrainReminder? _reminder;

    public TextItemGrain(
        IGrainContext grainContext,
        [PersistentState("text")] IPersistentState<TextItem> state,
        ILogger<TextItemGrain> logger)
    {
        _state = state;
        _logger = logger;
        GrainContext = grainContext;
    }

    public IGrainContext GrainContext { get; }
    
    /// <inheritdoc />
    public async Task OnActivateAsync(CancellationToken cancellationToken)
    {
        _reminder = await this.RegisterOrUpdateReminder("clear", TimeSpan.FromDays(10), TimeSpan.FromDays(10));
    }

    /// <inheritdoc />
    public async ValueTask<TextSetResult> SetText(string text)
    {
        try
        {
            if (_state.State.Text is not null)
                return TextSetResult.Failure;

            _state.State.Text = text;
            await _state.WriteStateAsync();

            return TextSetResult.Success;
        }
        catch (Exception)
        {
            return TextSetResult.Failure;
        }
    }

    /// <inheritdoc />
    public ValueTask<string> GetText()
    {
        return ValueTask.FromResult(_state.State.Text ?? throw new InvalidOperationException("No text was available"));
    }

    /// <inheritdoc />
    public async Task ReceiveReminder(string reminderName, TickStatus status)
    {
        if (reminderName == "clear")
        {
            _state.State.Text = null;
            await _state.WriteStateAsync(); 
            this.DeactivateOnIdle();
            
            _logger.LogInformation("Text item have been cleared!");
        }
    }
}