using KBR.Shared.Cache;
using Microsoft.Extensions.Caching.Distributed;

namespace KBR.Cache
{
    internal class AppDistributedCache : IAppDistributedCache
    {
        private readonly IDistributedCache _cache;
        private readonly DistributedCacheEntryOptions _entryOptions;

        public AppDistributedCache(IDistributedCache cache)
        {
            this._cache = cache;
            this._entryOptions = new DistributedCacheEntryOptions();
        }

        public T Get<T>(string key)
           where T : class
        {
            if (this._cache.Get(key) is var result && result != null)
            {
                return result.FromByteArray<T>();
            }

            return default;
        }

        public async Task<T> GetAsync<T>(string key, CancellationToken cancellationToken = default)
            where T : class
        {
            var result = await this._cache.GetAsync(key, cancellationToken);

            if (result != null)
            {
                return result.FromByteArray<T>();
            }

            return default;
        }

        public void Set<T>(string key, T obj, DistributedCacheEntryOptions? entryOptions = default)
        {
            this._cache.Set(key, obj.ToByteArray(), entryOptions ?? this._entryOptions);
        }

        public async Task SetAsync<T>(string key, T obj, DistributedCacheEntryOptions? entryOptions = default, CancellationToken cancellationToken = default)
        {
            await this._cache.SetAsync(key, obj.ToByteArray(), entryOptions ?? this._entryOptions, cancellationToken);
        }

        public void Remove(string key)
        {
            this._cache.Remove(key);
        }

        public async Task RemoveAsync(string key, CancellationToken cancellationToken = default)
        {
            await this._cache.RemoveAsync(key, cancellationToken);
        }

        public TItem GetOrCreate<TItem>(string key, Func<TItem> factory)
            where TItem : class
        {
            byte[] result = this._cache.Get(key);
            var resultData = result?.FromByteArray<TItem>();
            if (result == null || resultData == null)
            {
                var data = factory();
                this._cache.Set(key, data.ToByteArray(), this._entryOptions);
                return data;
            }

            return resultData;
        }

        public async Task<TItem> GetOrCreateAsync<TItem>(string key, Func<Task<TItem>> factory, CancellationToken cancellationToken = default)
             where TItem : class
        {
            byte[] result = await this._cache.GetAsync(key, cancellationToken);
            var resultData = result?.FromByteArray<TItem>();
            if (result == null || resultData == null)
            {
                var data = await factory();
                if (data != null)
                {
                    await this._cache.SetAsync(key, data.ToByteArray(), this._entryOptions, cancellationToken);
                }

                return data;
            }

            return resultData;
        }
    }
}