using BeWo.Data.Access;
using BeWo.ServerUtils.Core;
using BeWo.Service.Core;
using BS.Shared.DataContracts;
using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;

namespace BeWo.Service.Status
{
	public class BaseStatusService
	{
		private static readonly log4net.ILog log = LoggerUtils.GetLogger(System.Reflection.MethodBase.GetCurrentMethod().DeclaringType);

		private readonly string joinChar = Environment.NewLine;

		protected string Name { get; set; }

		protected List<Func<string>> Checkups { get; } = new List<Func<string>>();

		private List<WebConfigSetting> RequiredWebConfigs { get; } = new List<WebConfigSetting>();
		private List<WebSecretConfigSetting> RequiredWebSecretConfigs { get; } = new List<WebSecretConfigSetting>();
		private List<string> RequiredDBScripts { get; } = new List<string>();
		private List<SpecialConfig> RequiredConfigs { get; } = new List<SpecialConfig>();

		public BaseStatusService(string name)
		{
			Name = name;

			RegisterCheckup(CheckWebConfig,
				CheckWebSecretConfig,
				CheckDBScripts,
				CheckConfig);
		}

		protected void AddWebConfigCheck(params WebConfigSetting[] args)
		{
			RequiredWebConfigs.AddRange(args);
		}

		protected void AddWebSecretConfigCheck(params WebSecretConfigSetting[] args)
		{
			RequiredWebSecretConfigs.AddRange(args);
		}

		protected void AddDBScript(params string[] args)
		{
			RequiredDBScripts.AddRange(args);
		}

		protected void AddCustomConfig(params SpecialConfig[] args)
		{
			RequiredConfigs.AddRange(args);
		}

		protected void RegisterCheckup(params Func<string>[] args)
		{
			Checkups.AddRange(args);
		}

		public ServiceStatusDC DoHealthCheckup()
		{
			var errors = new List<string>();

			foreach (var func in Checkups)
			{
				try
				{
					var error = func();

					if (!string.IsNullOrEmpty(error))
						errors.Add(error);
				}
				catch (Exception ex)
				{
					log.Error($"Health-Checkup '{Name}' fehlgeschlagen", ex);
					errors.Add(ex.Message);
				}
			}

			return new ServiceStatusDC
			{
				Name = Name,
				IsOk = errors.Count == 0,
				Message = errors.Count == 0 ? "OK" : string.Join(joinChar, errors)
			};
		}

		private string CheckWebConfig()
		{
			var missing = RequiredWebConfigs
				.Where(x => string.IsNullOrWhiteSpace(MergedConfig.GetSetting(x)))
				.Select(x => $"'{x}' wurde nicht korrekt konfiguriert");

			return string.Join(joinChar, missing);
		}

		private string CheckWebSecretConfig()
		{
			var missing = RequiredWebSecretConfigs
				.Where(x => string.IsNullOrWhiteSpace(MergedConfig.GetSecretSetting(x)))
				.Select(x => $"'{x}' wurde nicht korrekt konfiguriert");

			return string.Join(joinChar, missing);
		}

		private string CheckDBScripts()
		{
			var missing = RequiredDBScripts
				.Where(x => !DAOFactory.ScriptDAO.IsScriptExecuted(x))
				.Select(x => $"Script '{x}' wurde nicht ausgeführt");

			return string.Join(joinChar, missing);
		}

		private string CheckConfig()
		{
			var missing = RequiredConfigs
				.Where(x => !File.Exists(ConfigReader.GetConfigPath(x)))
				.Select(x => $"SpecialConfig.{x} wurde nicht korrekt konfiguriert");

			return string.Join(joinChar, missing);
		}
	}
}