using Microsoft.Extensions.Configuration;
using Sarand.Net.Standard.Base.App;
using Sarand.Net.Standard.Base.Core;
using Sarand.Net.Standard.Base.Utils;
using Saxonite.Net.Standard.Base.App;
using System;
using System.Collections.Generic;
using System.Text;

namespace Saxonite.Net.Core.Web.Base.App
{
	//=======================================================================
	public class SaxAppConfig
	{
		//---------------------------------------------------------------
		// Data members.
		private readonly List<String> environments = new List<string>();

		//---------------------------------------------------------------
		// Construction.
		public SaxAppConfig(String context, ConfigurationSection configSection, SaxAppConfig defaultConfig)
		{
			Context = context;
			PopulateDefaults(defaultConfig);
			PopulateConfig(configSection);
		}

		//---------------------------------------------------------------
		// Properties.
		public String Context { get; }
		public List<String> Environments { get { return new List<String>(environments); } }
		public String Instance { get; set; } = "";
		// URLs.
		public class URLConfig
		{
			public class OnlineConfig
			{
				public String Root { get; set; }
			}
			public OnlineConfig Online { get; } = new OnlineConfig();
		}
		public URLConfig URL { get; } = new URLConfig();
		// Security.
		public class SecurityConfig
		{
			public class PasswordConfig
			{
				public int MinLength { get; set; }
			}
			public PasswordConfig Password { get; } = new PasswordConfig();
			public class SignUpConfig
			{
				public class ActivationConfig
				{
					public int EmailLinkExpiresMins = Sax.Config.Security.Activation.EmailLinkExpiresMins_Default;
				}
				public ActivationConfig Activation { get; } = new ActivationConfig();
			}
			public SignUpConfig SignUp { get; } = new SignUpConfig();
			public class SignInConfig
			{
				public class PasswordRequestConfig
				{
					public int EmailLinkExpiresMins = Sax.Config.Security.Activation.EmailLinkExpiresMins_Default;
				}
				public PasswordRequestConfig PasswordRequest { get; } = new PasswordRequestConfig();
				public class KeepLoggedInConfig
				{
					public bool Allowed { get; set; } = Sax.Config.Security.SignIn.KeepLoggedIn.Allowed_Default;
					public int CookieExpiresDays { get; set; } = Sax.Config.Security.SignIn.KeepLoggedIn.CookieExpiresDays_Default;
				}
				public KeepLoggedInConfig KeepLoggedIn { get; } = new KeepLoggedInConfig();
			}
			public SignInConfig SignIn { get; } = new SignInConfig();
		}
		public SecurityConfig Security { get; } = new SecurityConfig();
		// Email.
		public class EmailConfig
		{
			public class SpecificEmailConfig
			{
				public List<String> AddressesTo { get; } = new List<string>();
				public List<String> AddressesCc { get; } = new List<string>();
				public List<String> AddressesBcc { get; } = new List<string>();
			}
			public SpecificEmailConfig ContactUs { get; } = new SpecificEmailConfig();
			public SpecificEmailConfig Signup_Activate { get; } = new SpecificEmailConfig();
			public SpecificEmailConfig Signup_Welcome { get; } = new SpecificEmailConfig();
			public String Context { get; internal set; }
		}
		public EmailConfig Email { get; } = new EmailConfig();
		// Databases.
		public class DatabaseConfig
		{
			public String Location { get; internal set; }
			public String User { get; internal set; }
			public String Password { get; internal set; }
		}
		public class DatabasesConfig
		{
			public Dictionary<Sax.Database, DatabaseConfig> Databases { get; } = new Dictionary<Sax.Database, DatabaseConfig>();
			public DatabaseConfig Core { get { return Databases.GetValue(Sax.Database.Core, new DatabaseConfig()); } }
			public DatabaseConfig Reference { get { return Databases.GetValue(Sax.Database.Reference, new DatabaseConfig()); } }
			public DatabaseConfig Support { get { return Databases.GetValue(Sax.Database.Support, new DatabaseConfig()); } }
		}
		public DatabasesConfig Databases { get; } = new DatabasesConfig();
		// Documents.
		public class DocumentsConfig
		{
			public String RootFolder { get; internal set; }
		}
		public DocumentsConfig Documents { get; } = new DocumentsConfig();
		// Logging.
		public class LoggingConfig
		{
			public String RootFolder { get; internal set; }
		}
		public LoggingConfig Logging { get; } = new LoggingConfig();

		//---------------------------------------------------------------
		private void PopulateDefaults(SaxAppConfig defaultConfig)
		{
			if (defaultConfig == null) return;
			Security.Password.MinLength = defaultConfig.Security.Password.MinLength;
			Security.SignIn.KeepLoggedIn.Allowed = defaultConfig.Security.SignIn.KeepLoggedIn.Allowed;
			Security.SignIn.KeepLoggedIn.CookieExpiresDays = defaultConfig.Security.SignIn.KeepLoggedIn.CookieExpiresDays;
		}

		//---------------------------------------------------------------
		private void PopulateConfig(ConfigurationSection configSection)
		{
			if (configSection != null)
			{
				// Environments.
				foreach (ConfigurationSection environment in configSection.GetSection("Environments").GetChildren())
					environments.Add(StringUtil.TrimAll(environment.Value));
				Instance = StringUtil.OnEmpty(configSection["Instance"], Instance);

				// URLs.
				IConfigurationSection urls = configSection.GetSection("URLs");
				if (urls.Exists())
				{
					IConfigurationSection onlineUrls = urls.GetSection("Online");
					if (onlineUrls.Exists())
					{
						URL.Online.Root = onlineUrls["Root"];
					}
				}

				// Security.
				IConfigurationSection security = configSection.GetSection("Security");
				if (security.Exists())
				{
					// Security - Password.
					IConfigurationSection securityPassword = security.GetSection("Password");
					if (securityPassword.Exists())
					{
						Security.Password.MinLength = StringUtil.ToInt(securityPassword["MinLength"], Security.Password.MinLength);
					}
					// Security - Sign-Up.
					IConfigurationSection securitySignUp = security.GetSection("SignUp");
					if (securitySignUp.Exists())
					{
					}
					// Security - Sign-In.
					IConfigurationSection securitySignIn = security.GetSection("SignIn");
					if (securitySignIn.Exists())
					{
						IConfigurationSection keepLoggedIn = securitySignIn.GetSection("SignIn");
						if (keepLoggedIn.Exists())
						{
							Security.SignIn.KeepLoggedIn.Allowed = StringUtil.ToBool(StringUtil.OnEmpty(keepLoggedIn["Allowed"], Security.SignIn.KeepLoggedIn.Allowed.ToString()));
							Security.SignIn.KeepLoggedIn.CookieExpiresDays = StringUtil.ToInt(keepLoggedIn["CookieExpiresDays"], Security.SignIn.KeepLoggedIn.CookieExpiresDays);
						}
					}
				}

				// Email.
				IConfigurationSection email = configSection.GetSection("Email");
				if (email.Exists())
				{
					Email.Context = email["Context"];
					PopulateEmailConfig(Email.ContactUs, email.GetSection("ContactUs"));
					PopulateEmailConfig(Email.Signup_Activate, email.GetSection("Signup").GetSection("Activate"));
					PopulateEmailConfig(Email.Signup_Welcome, email.GetSection("Signup").GetSection("Welcome"));
				}

				// Documents.
				IConfigurationSection documents = configSection.GetSection("Documents");
				if (documents.Exists())
				{
					Documents.RootFolder = StringUtil.OnEmpty(documents["RootFolder"], Documents.RootFolder);
				}

				// Logging.
				IConfigurationSection logging = configSection.GetSection("Logging");
				if (logging.Exists())
				{
					Logging.RootFolder = StringUtil.OnEmpty(logging["RootFolder"], Logging.RootFolder);
				}

				// Database.
				ExtractDatabasesConfig(Databases, configSection.GetSection("Databases"));

				// Variants.
				foreach (ConfigurationSection variantSection in configSection.GetSection("Variants").GetChildren())
				{
					// Variants override selected values but must match the application root folder to identify a specific instance.
					String applicationRootPath = variantSection["ApplicationRootFolder"];
					if (StringUtil.IsEmpty(applicationRootPath)) continue;
					if (!SaxSystem.ApplicationFolder.EqualsCI(applicationRootPath)) continue;
					PopulateConfig(variantSection);
				}
			}
		}

		//---------------------------------------------------------------
		private void PopulateEmailConfig(EmailConfig.SpecificEmailConfig config, IConfigurationSection emailSection)
		{
			if (!emailSection.Exists()) return;
			foreach (var addressTo in emailSection.GetSection("AddressesTo").GetChildren())
				config.AddressesTo.Add(StringUtil.TrimAll(addressTo.Value));
			foreach (var addressCc in emailSection.GetSection("AddressesCc").GetChildren())
				config.AddressesCc.Add(StringUtil.TrimAll(addressCc.Value));
			foreach (var addressBcc in emailSection.GetSection("AddressesBcc").GetChildren())
				config.AddressesBcc.Add(StringUtil.TrimAll(addressBcc.Value));
		}

		//---------------------------------------------------------------
		private void ExtractDatabasesConfig(DatabasesConfig databases, IConfigurationSection databasesSection)
		{
			if (!databasesSection.Exists()) return;
			// 'Database' section contains a separate named configuration for each database: 'Core', 'Support' etc.
			foreach (var databaseSection in databasesSection.GetChildren())
				ExtractDatabaseConfig(databases, databaseSection);
		}

		//---------------------------------------------------------------
		private void ExtractDatabaseConfig(DatabasesConfig databases, IConfigurationSection databaseSection)
		{
			if (!databaseSection.Exists()) return;
			Sax.Database databaseType = EnumUtil.ParseEnum<Sax.Database>(databaseSection.Key);
			if (databaseType <= 0)
			{
				SaLogger.Warn($"{SysUtil.Fn} Unrecognised database: {databaseSection.Key}");
				return;
			}
			// Extract database configuration.
			DatabaseConfig database = new DatabaseConfig();
			database.Location = StringUtil.OnEmpty(databaseSection["Location"], database.Location);
			database.User = StringUtil.OnEmpty(databaseSection["User"], database.User);
			database.Password = StringUtil.OnEmpty(databaseSection["Password"], database.Password);
			databases.Databases.Add(databaseType, database);
		}

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