EnvelopeGenerator/EnvelopeGenerator.Application/Extensions/CacheExtensions.cs

using Microsoft.Extensions.Caching.Distributed;

namespace EnvelopeGenerator.Application.Extensions;

/// <summary>
/// 
/// </summary>
public static class CacheExtensions
{
    /// <summary>
    /// 
    /// </summary>
    /// <param name="cache"></param>
    /// <param name="key"></param>
    /// <param name="value"></param>
    /// <param name="options"></param>
    /// <param name="cToken"></param>
    /// <returns></returns>
    public static Task SetLongAsync(this IDistributedCache cache, string key, long value, DistributedCacheEntryOptions? options = null, CancellationToken cToken = default)
        => options is null
            ? cache.SetAsync(key, BitConverter.GetBytes(value), token: cToken)
            : cache.SetAsync(key, BitConverter.GetBytes(value), options: options, token: cToken);

    /// <summary>
    /// 
    /// </summary>
    /// <param name="cache"></param>
    /// <param name="key"></param>
    /// <param name="cToken"></param>
    /// <returns></returns>
    public static async Task<long?> GetLongAsync(this IDistributedCache cache, string key, CancellationToken cToken = default)
    {
        var value = await cache.GetAsync(key, cToken);
        return value is null ? null : BitConverter.ToInt64(value, 0);
    }

    /// <summary>
    /// 
    /// </summary>
    /// <param name="cache"></param>
    /// <param name="key"></param>
    /// <param name="value"></param>
    /// <param name="options"></param>
    /// <param name="cToken"></param>
    /// <returns></returns>
    public static Task SetDateTimeAsync(this IDistributedCache cache, string key, DateTime value, DistributedCacheEntryOptions? options = null, CancellationToken cToken = default)
        => cache.SetLongAsync(key: key, value: value.Ticks, options: options, cToken: cToken);

    /// <summary>
    /// 
    /// </summary>
    /// <param name="cache"></param>
    /// <param name="key"></param>
    /// <param name="cToken"></param>
    /// <returns></returns>
    public static async Task<DateTime?> GetDateTimeAsync(this IDistributedCache cache, string key, CancellationToken cToken = default)
    {
        var value = await cache.GetAsync(key, cToken);
        return value is null ? null : new(BitConverter.ToInt64(value, 0));
    }

    /// <summary>
    /// 
    /// </summary>
    /// <param name="cache"></param>
    /// <param name="key"></param>
    /// <param name="value"></param>
    /// <param name="options"></param>
    /// <param name="cToken"></param>
    /// <returns></returns>
    public static Task SetTimeSpanAsync(this IDistributedCache cache, string key, TimeSpan value, DistributedCacheEntryOptions? options = null, CancellationToken cToken = default)
        => cache.SetLongAsync(key: key, value: value.Ticks, options: options, cToken);

    /// <summary>
    /// 
    /// </summary>
    /// <param name="cache"></param>
    /// <param name="key"></param>
    /// <param name="cToken"></param>
    /// <returns></returns>
    public static async Task<TimeSpan?> GetTimeSpanAsync(this IDistributedCache cache, string key, CancellationToken cToken = default)
    {
        var value = await cache.GetAsync(key, cToken);
        return value is null ? null : new(BitConverter.ToInt64(value, 0));
    }

    //TODO: use code generator
    #region GetOrSetAsync

    #region string

    /// <summary>
    /// 
    /// </summary>
    /// <param name="cache"></param>
    /// <param name="key"></param>
    /// <param name="factory"></param>
    /// <param name="options"></param>
    /// <param name="cacheInBackground"></param>
    /// <param name="cToken"></param>
    /// <returns></returns>
    public static async Task<string> GetOrSetAsync(this IDistributedCache cache, string key, Func<string> factory, DistributedCacheEntryOptions? options = null, bool cacheInBackground = false, CancellationToken cToken = default)
    {
        var value = await cache.GetStringAsync(key, cToken);
        if (value is null)
        {
            // create new and save
            value = factory();

            Task CacheAsync() => options is null
                    ? cache.SetStringAsync(key, value, cToken)
                    : cache.SetStringAsync(key, value, options, cToken);

            if (cacheInBackground)
                _ = Task.Run(async () => await CacheAsync(), cToken);
            else
                await CacheAsync();
        }

        return value;
    }

    /// <summary>
    /// 
    /// </summary>
    /// <param name="cache"></param>
    /// <param name="key"></param>
    /// <param name="factoryAsync"></param>
    /// <param name="options"></param>
    /// <param name="cacheInBackground"></param>
    /// <param name="cToken"></param>
    /// <returns></returns>
    public static async Task<string> GetOrSetAsync(this IDistributedCache cache, string key, Func<Task<string>> factoryAsync, DistributedCacheEntryOptions? options = null, bool cacheInBackground = false, CancellationToken cToken = default)
    {
        var value = await cache.GetStringAsync(key, cToken);
        if(value is null)
        {
            // create new and save
            value = await factoryAsync();

            Task CacheAsync() => options is null
                ? cache.SetStringAsync(key: key, value: value, token: cToken)
                : cache.SetStringAsync(key: key, value: value, options: options, token: cToken);

            if (cacheInBackground)
                _ = Task.Run(async () => await CacheAsync(), cToken);
            else
                await CacheAsync();
        }

        return value;
    }
    #endregion

    #region DateTime
    /// <summary>
    /// 
    /// </summary>
    /// <param name="cache"></param>
    /// <param name="key"></param>
    /// <param name="factory"></param>
    /// <param name="options"></param>
    /// <param name="cacheInBackground"></param>
    /// <param name="cToken"></param>
    /// <returns></returns>
    public static async Task<DateTime> GetOrSetAsync(this IDistributedCache cache, string key, Func<DateTime> factory, DistributedCacheEntryOptions? options = null, bool cacheInBackground = false, CancellationToken cToken = default)
    {
        if (await cache.GetDateTimeAsync(key, cToken) is DateTime dateTimeValue)
            return dateTimeValue;
        else
        {
            // create new and save
            var newValue = factory();

            Task CacheAsync() => options is null
                    ? cache.SetDateTimeAsync(key, newValue, cToken: cToken)
                    : cache.SetDateTimeAsync(key, newValue, options, cToken);

            if (cacheInBackground)
                _ = Task.Run(async () => await CacheAsync(), cToken);
            else
                await CacheAsync();

            return newValue;
        }
    }

    /// <summary>
    /// 
    /// </summary>
    /// <param name="cache"></param>
    /// <param name="key"></param>
    /// <param name="factory"></param>
    /// <param name="options"></param>
    /// <param name="cacheInBackground"></param>
    /// <param name="cToken"></param>
    /// <returns></returns>
    public static async Task<DateTime> GetOrSetAsync(this IDistributedCache cache, string key, Func<Task<DateTime>> factory, DistributedCacheEntryOptions? options = null, bool cacheInBackground = false, CancellationToken cToken = default)
    {
        if (await cache.GetDateTimeAsync(key, cToken) is DateTime dateTimeValue)
            return dateTimeValue;
        else
        {
            // create new and save
            var newValue = await factory();

            Task CacheAsync() => options is null
                    ? cache.SetDateTimeAsync(key, newValue, cToken: cToken)
                    : cache.SetDateTimeAsync(key, newValue, options, cToken);

            if (cacheInBackground)
                _ = Task.Run(async () => await CacheAsync(), cToken);
            else
                await CacheAsync();

            return newValue;
        }
    }
    #endregion

    #endregion
}