using dodohold.core;
using System.Security.Cryptography;
using System.Text;

namespace molilian.core
{
    public static class TaobaoShortLinkCacheCore
    {
        public const int CacheExpireSeconds = 7 * 86400;

        public static async Task<string?> GetAsync(string shortUrl)
        {
            try
            {
                string longUrl = await CenterHub.Redis.GetAsync<string>(GetCacheKey(shortUrl));
                return IsLongUrl(longUrl) ? longUrl : null;
            }
            catch (Exception ex)
            {
                LogFailure("read", ex);
                return null;
            }
        }

        public static string? Get(string shortUrl)
        {
            try
            {
                string longUrl = CenterHub.Redis.Get<string>(GetCacheKey(shortUrl));
                return IsLongUrl(longUrl) ? longUrl : null;
            }
            catch (Exception ex)
            {
                LogFailure("read", ex);
                return null;
            }
        }

        public static async Task SaveAsync(string shortUrl, string longUrl)
        {
            if (!IsLongUrl(longUrl)) return;
            try
            {
                await CenterHub.Redis.SetAsync(GetCacheKey(shortUrl), longUrl, CacheExpireSeconds);
            }
            catch (Exception ex)
            {
                LogFailure("write", ex);
            }
        }

        public static void Save(string shortUrl, string longUrl)
        {
            if (!IsLongUrl(longUrl)) return;
            try
            {
                CenterHub.Redis.Set(GetCacheKey(shortUrl), longUrl, CacheExpireSeconds);
            }
            catch (Exception ex)
            {
                LogFailure("write", ex);
            }
        }

        private static bool IsLongUrl(string? url)
        {
            return Uri.TryCreate(url, UriKind.Absolute, out var uri) &&
                (uri.Scheme == Uri.UriSchemeHttp || uri.Scheme == Uri.UriSchemeHttps) &&
                !AlimamaPlus.IsShortLink(url!);
        }

        private static string GetCacheKey(string shortUrl)
        {
            string hash = Convert.ToHexString(SHA256.HashData(Encoding.UTF8.GetBytes(shortUrl.Trim())));
            return $"cache:taobao:short_link_http:v1:{hash}";
        }

        private static void LogFailure(string operation, Exception ex)
        {
            _ = new LoggerLibrary("taobao_short_link_cache", operation)
                .Info(ex.Message, ex.StackTrace)
                .SaveAsync();
        }
    }
}