using Elsa.Caching.Models;
using Microsoft.Extensions.Caching.Memory;

namespace Elsa.Caching.Services;

public class MemoryCacheProvider(IMemoryCache cache, IChangeTokenSignaler signaler) : ICacheProvider
{
    public bool IsShared => false;
    public Task<CacheResult<T>> GetAsync<T>(string key, CancellationToken cancellationToken = default)
    {
        var found = cache.TryGetValue(key, out T? value);
        return Task.FromResult(new CacheResult<T>(found, value));
    }

    public Task SetAsync<T>(string key, T? value, CacheEntryOptions options, CancellationToken cancellationToken = default)
    {
        var memoryOptions = new MemoryCacheEntryOptions
        {
            AbsoluteExpirationRelativeToNow = options.AbsoluteExpirationRelativeToNow,
            SlidingExpiration = options.SlidingExpiration
        };
        foreach (var tag in options.Tags) memoryOptions.AddExpirationToken(signaler.GetToken(tag));
        cache.Set(key, value, memoryOptions);
        return Task.CompletedTask;
    }

    public Task RemoveAsync(string key, CancellationToken cancellationToken = default)
    {
        cache.Remove(key);
        return Task.CompletedTask;
    }
}