PlanTempusApp/Core/Configurations/SmartConfigProvider/SmartConfigExtension.cs

using Core.Configurations.JsonConfigProvider;
using Core.Configurations.SmartConfigProvider;
using Core.Exceptions;
using Newtonsoft.Json;
using Newtonsoft.Json.Linq;

namespace Core.Configurations.SmartConfig
{
    public static class SmartConfigExtension
    {
        /// <summary>
        /// 
        /// </summary>
        /// <param name="builder"></param>
        /// <param name="configKey">Name of key</param>
        /// <param name="path">If this is different than the default ConnectionStrings-element, then configure it.</param>
        /// <returns></returns>
        public static IConfigurationBuilder AddSmartConfig(this IConfigurationBuilder builder, string configKey = "DefaultConnection", string path = null)
        {
            return builder.AddProvider(new SmartConfigProvider(builder, configKey, path));
        }
        public static IConfigurationBuilder AddSmartConfig(this IConfigurationBuilder builder, Action<SmartConfigOptions> setupAction)
        {
            var options = new SmartConfigOptions();
            setupAction(options);

            return builder.AddProvider(new SmartConfigProvider(options.GetRepository()));
        }
    }
    public class SmartConfigOptions
    {
        private SmartConfiguration.IConfigurationRepository _repository;

        public SmartConfigOptions UseRepository(SmartConfiguration.IConfigurationRepository repository)
        {
            _repository = repository;
            return this;
        }

        internal SmartConfiguration.IConfigurationRepository GetRepository() => _repository;
    }
    public class SmartConfigProvider : IConfigurationProvider
    {
        string _configKey;
        string _connectionString;
        string _path;
        IConfigurationBuilder _builder;

        Newtonsoft.Json.Linq.JObject _configuration;


        public SmartConfigProvider() { }

        public SmartConfigProvider(SmartConfiguration.IConfigurationRepository configurationProvider)
        { }
        public SmartConfigProvider(IConfigurationBuilder builder, string configKey, string configurationFilePath)
        {
            _builder = builder;
            _configKey = configKey;
            _path = configurationFilePath;
            SetConnectionString();
        }

        void SetConnectionString()
        {
            var carrier = _builder.ConfigurationProviders.OfType<IHasConfigurationFilePath>().SingleOrDefault();

            if (carrier?.ConfigurationFilePath is null && _path is null)
                throw new ConfigurationException($"Expected a previous added ConfigurationProvider with IHasConfigurationFilePath or a configurationFilePath where to find the appsettingsfile");

            _path ??= carrier.ConfigurationFilePath;

            if (!File.Exists(_path))
                throw new ConfigurationException($"File not found, configurationFilePath: {_path}");


            using (StreamReader file = File.OpenText(_path))
            using (JsonTextReader reader = new JsonTextReader(file))
            {
                var jsonConfiguration = (Newtonsoft.Json.Linq.JObject)Newtonsoft.Json.Linq.JToken.ReadFrom(reader);

                _connectionString = jsonConfiguration.SelectToken($"ConnectionStrings.{_configKey}")?.ToString();
            }
        }
        public void Build()
        {
            var repository = new ConfigurationRepository(_connectionString);
            var configs = repository.GetActiveConfigurations();

            var pairs = configs.Select(x => new KeyValuePair<string, JToken>(x.Key, JToken.Parse(x.Value.ToString())));

            _configuration = Common.KeyValueToJson.Convert(pairs);

        }

        public Newtonsoft.Json.Linq.JObject Configuration()
        {
            return _configuration;
        }
    }
}