// ==========================================================================
//  Squidex Headless CMS
// ==========================================================================
//  Copyright (c) Squidex UG (haftungsbeschraenkt)
//  All rights reserved. Licensed under the MIT license.
// ==========================================================================

using Microsoft.Extensions.Caching.Memory;

namespace Squidex.Infrastructure.UsageTracking
{
    public sealed class CachingUsageTracker : IUsageTracker
    {
        private static readonly TimeSpan CacheDuration = TimeSpan.FromMinutes(5);
        private readonly IUsageTracker inner;
        private readonly IMemoryCache cache;

        public string FallbackCategory => inner.FallbackCategory;

        public CachingUsageTracker(IUsageTracker inner, IMemoryCache cache)
        {
            this.inner = inner;
            this.cache = cache;
        }

        public Task DeleteAsync(string key,
            CancellationToken ct = default)
        {
            Guard.NotNull(key);

            return inner.DeleteAsync(key, ct);
        }

        public Task DeleteByKeyPatternAsync(string pattern,
            CancellationToken ct = default)
        {
            Guard.NotNull(pattern);

            return inner.DeleteByKeyPatternAsync(pattern, ct);
        }

        public Task<Dictionary<string, List<(DateTime, Counters)>>> QueryAsync(string key, DateTime fromDate, DateTime toDate,
            CancellationToken ct = default)
        {
            Guard.NotNull(key);

            return inner.QueryAsync(key, fromDate, toDate, ct);
        }

        public Task TrackAsync(DateTime date, string key, string? category, Counters counters,
            CancellationToken ct = default)
        {
            Guard.NotNull(key);

            return inner.TrackAsync(date, key, category, counters, ct);
        }

        public Task<Counters> GetForMonthAsync(string key, DateTime date, string? category,
            CancellationToken ct = default)
        {
            Guard.NotNull(key);

            var cacheKey = $"{typeof(CachingUsageTracker)}_UsageForMonth_{key}_{date}_{category}";

            return cache.GetOrCreateAsync(cacheKey, entry =>
            {
                entry.AbsoluteExpirationRelativeToNow = CacheDuration;

                return inner.GetForMonthAsync(key, date, category, ct);
            });
        }

        public Task<Counters> GetAsync(string key, DateTime fromDate, DateTime toDate, string? category,
            CancellationToken ct = default)
        {
            Guard.NotNull(key);

            var cacheKey = $"{typeof(CachingUsageTracker)}_Usage_{key}_{fromDate}_{toDate}_{category}";

            return cache.GetOrCreateAsync(cacheKey, entry =>
            {
                entry.AbsoluteExpirationRelativeToNow = CacheDuration;

                return inner.GetAsync(key, fromDate, toDate, category, ct);
            });
        }
    }
}