using Microsoft.AspNetCore.Hosting;
using Microsoft.Extensions.Configuration;
using Microsoft.Extensions.Hosting;
using Sarand.Net.Standard.Base.App;
using Sarand.Net.Standard.Base.Core;
using Sarand.Net.Standard.Base.Dbas;
using Sarand.Net.Standard.Base.Email;
using Sarand.Net.Standard.Base.IO;
using Sarand.Net.Standard.Base.Utils;
using Sarand.Net.Standard.Dbas.Base;
using Sarand.Net.Standard.Dbas.Data;
using Saxonite.Net.Core.Web.Base.Consoles;
using Saxonite.Net.Standard.Base.App;
using Saxonite.Net.Standard.Base.Consoles;
using Saxonite.Net.Standard.Base.Helpers;
using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Text;

namespace Saxonite.Net.Core.Web.Base.App
{
	//=======================================================================
	public abstract class SaxApplication_Web : SaxApplication_Base
	{
		//-------------------------------------------------------------------
		// Data members.
		protected Sax.InstanceType instanceType;
		protected String environmentName = "";
		// Session context.
		protected class SessionContextData_Web
		{
			public SessionContextData_Web(SaxSessionContext_Web sessionContext)
			{
				SessionContext = sessionContext;
			}
			public SaxSessionContext_Web SessionContext { get; }
			public Dictionary<Sax.Database, ISacsDatabase> Databases { get; } = new Dictionary<Sax.Database, ISacsDatabase>();
			public ISacsDatabase CoreDatabase { get { return Databases.GetValue(Sax.Database.Core, null); } }
			public ISacsDatabase ReferenceDatabase { get { return Databases.GetValue(Sax.Database.Reference, null); } }
			public ISacsDatabase SupportDatabase { get { return Databases.GetValue(Sax.Database.Support, null); } }
		}

		//-------------------------------------------------------------------
		// Protected construction.
		protected SaxApplication_Web(Sax.Application applicationType)
		{
			WebApp = this;
			System_Web = new SaxSystem_Web();
			ApplicationType = applicationType;
		}
		protected override void Dispose(bool disposing)
		{
			if (disposing)
			{
				WebApp = null;
				System_Web = null;
			}
			base.Dispose(disposing);
		}

		//-------------------------------------------------------------------
		// Globals.
		public static SaxApplication_Web WebApp { get; private set; }
		public Sax.Application ApplicationType { get; }
		public override SaxSystem System { get { return System_Web; } }
		public SaxSystem_Web System_Web { get; private set; }
		// Application instance.
		public override Sax.InstanceType InstanceType { get { return instanceType; } }
		public override String EnvironmentName { get { return environmentName; } }
		public bool Development { get; protected set; }
		public String LoggingRootFolder { get; protected set; } = "";
		// Application components.
		public abstract String SessionCookieName { get; }
		public virtual SaxSessionContext SessionContext { get; protected set; }
		public abstract SaxAppConfig AppConfig { get; }
		public SaxConsoleHelper_Web ConsoleHelper_Web { get; protected set; }
		public override IDatabaseInfo CreateDbInfo(SaxSessionContext sessionContext, Sax.Database databaseType) { return new DbDataItem.DatabaseInfo(GetDatabase(sessionContext, databaseType)); }
		// Configuration.
		public IConfiguration Configuration { get; protected set; }
		public IConfiguration SaxConfiguration { get; private set; }

		//-------------------------------------------------------------------
		protected void InitEnvironment(IWebHostEnvironment env, String logFilenamePrefix)
		{
			Development = env.IsDevelopment();
			environmentName = env.EnvironmentName;
			SaxConfiguration = LoadApplicationConfiguration();

			// Configure logging.
			SaLogger.LogFilenamePrefix = logFilenamePrefix;
			SaLogger.IncludeHostInFileMessage = false;
			SaLogger.IncludeUserInFileMessage = false;

			//Messages.Add($"Host: {SaxSystem.ComputerName}");
			//Messages.Add($"Config file: appsettings.machine.{SaxSystem.ComputerName}.json");
		}

		//-------------------------------------------------------------------
		// Application configuration.
		private IConfiguration LoadApplicationConfiguration()
		{
			// Load configuration resource files.
			// Later files override values from previous.
			var builder =
				new ConfigurationBuilder()
				.SetBasePath(Directory.GetCurrentDirectory())
				.AddEnvironmentVariables();

			// Saxonite Web configuration - shared by all applications.
			Stream configStream = SaxResourceHelper.GetResourceStream("appsettings.json", "Config");
			if (configStream != null) builder.AddJsonStream(configStream);
			configStream = SaxResourceHelper.GetResourceStream($"appsettings.{environmentName}.json", "Config");
			if (configStream != null) builder.AddJsonStream(configStream);
			configStream = SaxResourceHelper.GetResourceStream($"appsettings.machine.{SaxSystem.ComputerName}.json", "Config");
			if (configStream != null) builder.AddJsonStream(configStream);

			// Application specific configuration.
			builder
				.AddJsonFile("appsettings.json", optional: true, reloadOnChange: false)
				.AddJsonFile($"appsettings.{environmentName}.json", optional: true, reloadOnChange: false)
				.AddJsonFile($"appsettings.machine.{SaxSystem.ComputerName}.json", optional: true, reloadOnChange: false);

			return builder.Build();
		}

		//-------------------------------------------------------------------
		// Database configuration.
		protected void ConfigureDatabaseConnection(SessionContextData_Web sessionContextData, Sax.Database databaseInstance)
		{
			// Configure database connection.
			SaxAppConfig.DatabaseConfig databaseConfig = AppConfig.Databases.Databases.GetValue(databaseInstance, new SaxAppConfig.DatabaseConfig());
			SacsDatabaseConsole.OdbcConfig config = new SacsDatabaseConsole.OdbcConfig();
			config.Location = databaseConfig.Location;
			config.User = databaseConfig.User;
			config.Password = databaseConfig.Password;
			SacsDatabase database = SacsDatabaseConsole.OpenOdbcDatabase(config);
			if (database.HasErrorState())
				SaLogger.Warn(SysUtil.Fn + " " + databaseInstance.ToString() + " Database initialisation error: " + database.ErrorStateMessage);
			sessionContextData.Databases.Add(databaseInstance, database);
		}

		//-------------------------------------------------------------------
		// Logging.
		protected void LogApplicationStart(String fn)
		{
			// Log application start.
			List<StringPair> applicationParams = new List<StringPair>();
			applicationParams.Add("Host", SaxSystem.ComputerName);
			applicationParams.Add("Version", Sax.Version.GetFullVersion());
			applicationParams.Add("Instance", InstanceType.ToString() + (!StringUtil.IsEmpty(AppConfig.Instance) ? " [" + AppConfig.Instance + "]" : ""));
			applicationParams.Add("Configuration", SaxSystem.DebugMode ? "Debug" : "Release");
			applicationParams.Add("Environment", EnvironmentName);
			if (!StringUtil.IsBlank(AppConfig.Databases.Core.Location))
				applicationParams.Add("Database - Core", AppConfig.Databases.Core.Location);
			if (!StringUtil.IsBlank(AppConfig.Databases.Reference.Location))
				applicationParams.Add("Database - Reference", AppConfig.Databases.Reference.Location);
			if (!StringUtil.IsBlank(AppConfig.Databases.Support.Location))
				applicationParams.Add("Database - Support", AppConfig.Databases.Support.Location);
			applicationParams.Add("Application root", SaxSystem.ApplicationFolder);
			if (!StringUtil.IsEmpty(AppConfig.Documents.RootFolder))
				applicationParams.Add("Documents root", AppConfig.Documents.RootFolder);
			applicationParams.Add("Email context", AppConfig.Email.Context + (!StringUtil.IsEmpty(EmailConfig.SMTP.Server) ? " [" + EmailConfig.SMTP.Server + "]" : ""));
			SaLogger.Info(fn + " Application start." + applicationParams.Select(item => StringUtil.PadRight(item.Item1 + ":", 23, ' ') + " " + item.Item2).Concat("", "\n\t"), true);
			if (StringUtil.IsEmpty(EmailConfig.SMTP.Server) || StringUtil.IsEmpty(EmailConfig.Message.AddressFrom))
				SaLogger.Warn(fn + " Incomplete email configuration.", true);
		}

		//-------------------------------------------------------------------
		protected void InitialiseTemporaryLoggingFolder()
		{
			// Default logging folder - in case of startup failure.
			try
			{
				foreach (String folder in new String[] { @"D:\Sarand\Projects\User\AHoward\VS2017\Saxonite\Logs" })
				{
					if (DirectoryUtil.DirectoryExists(folder))
					{
						SaLogger.LogFolder = folder;
						break;
					}
				}
			}
			catch (Exception) { }
		}

		//-------------------------------------------------------------------
	}
	//=======================================================================
}