//
//  Class:			LocodeDB
//	Current CLR:	4.0.30319.42000
//	System:			Microsoft Visual Studio 10.0
//	Author:			dani
// 	Created:		1/9/2016 10:10:20 PM
//
//	Copyright (c) 2016 Informatikbüro Daniel Schick. All rights reserved.

using System;
using System.Collections.Generic;
using System.Data;
using System.Data.SQLite;
using bsmd.database;
using log4net;

namespace ENI2.Locode
{
    /// <summary>
    /// Locodes suchen (zu Orten), die DB ist aus einem github Projekt:
    /// https://github.com/kabisa/un_locode
    /// </summary>
    public static class LocodeDB
    {
        private static readonly SQLiteConnection _con;
        private const string _locode_DB_NAME = "db.sqlite";
        private static readonly ILog _log = LogManager.GetLogger(typeof(LocodeDB));

        static LocodeDB()
        {
            _con = new SQLiteConnection(string.Format("data source={0}; Version=3;", _locode_DB_NAME));
            _con.Open();
        }

        #region public static methods

        public static string LocodeGERFromCity(string city)
        {
            return LocodeDB.LocodeFromCity(city, "DE");
        }

        /// <summary>
        /// Lookup and create locode from local sqlite database
        /// </summary>        
        public static string LocodeFromCity(string city, string country)
        {
            string result = null;
            string query = string.Format("SELECT city_code FROM locodes JOIN countries ON locodes.country_id = countries.ID WHERE countries.code = '{0}' AND locodes.port='t' AND (locodes.name like '{1}' OR locodes.name_wo_diacritics like '{1}')",
                country, city);
            SQLiteCommand cmd = new SQLiteCommand(query, _con);
            IDataReader reader = cmd.ExecuteReader();
            while (reader.Read())
            {
                result = reader.GetString(0);
                break;
            }
            reader.Close();
            cmd.Dispose();
            if (result != null)
                result = string.Format("{0}{1}", country, result);
            return result;
        }        


        public static List<string> AllLocodesForCityName(string city)
        {
            List<string> results = new List<string>();
            if(city.Contains(","))
            {
                string[] elems = city.Split(',');
                string countryCode = CountryCodeFromName(elems[1].Trim());
                string lcLookup = LocodeFromCity(elems[0].Trim(), countryCode);
                if ((countryCode != null) && (lcLookup != null))
                    results.Add(lcLookup);
            }
            string query = string.Format("SELECT city_code, countries.code FROM locodes JOIN countries ON locodes.country_id = countries.ID WHERE locodes.port='t' AND (locodes.name like '{0}' OR locodes.name_wo_diacritics like '{0}')", city);
            SQLiteCommand cmd = new SQLiteCommand(query, _con);
            IDataReader reader = cmd.ExecuteReader();
            while (reader.Read())
            {
                if (!reader.IsDBNull(0) && !reader.IsDBNull(1))
                    results.Add(string.Format("{0}{1}", reader.GetString(1), reader.GetString(0)));                
            }
            reader.Close();
            cmd.Dispose();
            return results;
        }        

        public static List<LocodeEntry> AllLocodesForCityNameAsEntries(string city, bool onlyPorts = true)
        {
            List<LocodeEntry> results = new List<LocodeEntry>();
            if (city.Contains(","))
            {
                string[] elems = city.Split(',');
                string countryCode = CountryCodeFromName(elems[1].Trim());
                string lcLookup = LocodeFromCity(elems[0].Trim(), countryCode);
                if ((countryCode != null) && (lcLookup != null))
                {
                    LocodeEntry entry = new LocodeEntry();
                    entry.Locode = lcLookup;
                    entry.Name = elems[0].Trim();
                    results.Add(entry);
                }
            }

            string query = "SELECT locodes.name_wo_diacritics, city_code, countries.code FROM locodes JOIN countries ON locodes.country_id = countries.ID WHERE locodes.port='t' AND (locodes.name like $PAR OR locodes.name_wo_diacritics like $PAR)";
            if(!onlyPorts)
                query = "SELECT locodes.name_wo_diacritics, city_code, countries.code FROM locodes JOIN countries ON locodes.country_id = countries.ID WHERE (locodes.name like $PAR OR locodes.name_wo_diacritics like $PAR)";

            SQLiteCommand cmd = new SQLiteCommand(query, _con);
            cmd.Parameters.AddWithValue("$PAR", city);
            IDataReader reader = cmd.ExecuteReader();
            while (reader.Read())
            {
                if (!reader.IsDBNull(1) && !reader.IsDBNull(2)) {
                    LocodeEntry entry = new LocodeEntry();
                    entry.Locode = string.Format("{0}{1}", reader.GetString(2), reader.GetString(1));
                    if (!reader.IsDBNull(0))
                        entry.Name = reader.GetString(0);
                    results.Add(entry);
                }
            }
            reader.Close();
            cmd.Dispose();
            return results;
        }

        /// <summary>
        /// Lookup 2CHAR Country Code from country name (like search). Hopefully this will result in many hits
        /// </summary>        
        public static string CountryCodeFromName(string countryName)
        {
            string result = null;
            string query = string.Format("SELECT code FROM countries WHERE countries.name like @COUNTRY");
                
            SQLiteCommand cmd = new SQLiteCommand(query, _con);
            cmd.Parameters.Add(new SQLiteParameter("@COUNTRY", countryName));
            IDataReader reader = cmd.ExecuteReader();
            while (reader.Read())
            {
                result = reader.GetString(0);
                break;
            }
            reader.Close();
            cmd.Dispose();
            return result;
        }

        /// <summary>
        /// Get Name from LOCODE (any! type of locode, not just ports)
        /// </summary>        
        public static string NameFromLocode(string locode)
        {
            if (locode.IsNullOrEmpty()) return null;
            if (locode.Length != 5) return null;

            string result = null;
            try
            {
                string locodeUpper = locode.ToUpper();
                string query = string.Format("SELECT locodes.name_wo_diacritics FROM locodes JOIN countries ON locodes.country_id = countries.ID WHERE locodes.city_code = '{0}' AND countries.code = '{1}'",
                    locodeUpper.Substring(2), locodeUpper.Substring(0, 2));
                SQLiteCommand cmd = new SQLiteCommand(query, _con);
                IDataReader reader = cmd.ExecuteReader();
                while (reader.Read())
                {
                    if (!reader.IsDBNull(0))
                        result = reader.GetString(0);
                    break;
                }
                reader.Close();
                cmd.Dispose();
            }
            catch (Exception ex)
            {
                _log.WarnFormat("Error on locode lookup: {0}", ex.Message);
            }
            return result;
        }

        /// <summary>
        /// Get Portname from LOCODE
        /// </summary>        
        public static string PortNameFromLocode(string locode)
        {
            if (locode.IsNullOrEmpty()) return null;
            if (locode.Length != 5) return null;

            string result = null;
            try
            {
                string locodeUpper = locode.ToUpper();
                string query = string.Format("SELECT locodes.name_wo_diacritics FROM locodes JOIN countries ON locodes.country_id = countries.ID WHERE locodes.port='t' AND locodes.city_code = '{0}' AND countries.code = '{1}'",
                    locodeUpper.Substring(2), locodeUpper.Substring(0, 2));
                SQLiteCommand cmd = new SQLiteCommand(query, _con);
                IDataReader reader = cmd.ExecuteReader();
                while (reader.Read())
                {
                    if (!reader.IsDBNull(0))
                        result = reader.GetString(0);
                    break;
                }
                reader.Close();
                cmd.Dispose();
            }
            catch(Exception ex)
            {
                _log.WarnFormat("Error on locode lookup: {0}", ex.Message);
            }
            return result;
        }

        /// <summary>
        /// SSN Portname from Locode (for validation)
        /// </summary>
        public static string SSNPortNameFromLocode(string locode)
        {
            if (locode.IsNullOrEmpty()) return null;
            if (locode.Length != 5) return null;

            try
            {

                string result = null;
                string query = string.Format("SELECT LocationName FROM SSN_LOCODES WHERE LocationCode = '{0}'", locode);

                SQLiteCommand cmd = new SQLiteCommand(query, _con);
                IDataReader reader = cmd.ExecuteReader();
                while (reader.Read())
                {
                    if (!reader.IsDBNull(0))
                        result = reader.GetString(0);
                    break;
                }
                reader.Close();
                cmd.Dispose();
                return result;
            }
            catch (Exception ex)
            {
                _log.WarnFormat("error reading SSN location from locode: {0}", ex.ToString());
                return null;
            }
        }


        /// <summary>
        /// Get Locationname from LOCODE
        /// </summary>
        /// <param name="locode"></param>
        /// <returns></returns>
        public static string LocationNameFromLocode(string locode)
        {
            if (locode.IsNullOrEmpty()) return null;
            if (locode.Length != 5) return null;
            try
            {
                string result = null;
                string query = string.Format("SELECT locodes.name_wo_diacritics FROM locodes JOIN countries ON locodes.country_id = countries.ID WHERE locodes.city_code = '{0}' AND countries.code = '{1}'",
                    locode.Substring(2), locode.Substring(0, 2));
                SQLiteCommand cmd = new SQLiteCommand(query, _con);
                IDataReader reader = cmd.ExecuteReader();
                while (reader.Read())
                {
                    if (!reader.IsDBNull(0))
                        result = reader.GetString(0);
                    break;
                }
                reader.Close();
                cmd.Dispose();
                return result;
            }
            catch(Exception ex)
            {
                _log.WarnFormat("error reading location from locode: {0}", ex.ToString());
                return null;
            }
        }

        public static void CloseDB()
        {
            _con.Close();
        }

        #endregion

        #region class LocodeEntry

        public class LocodeEntry : IComparable
        {
            public string Locode { get; set; }
            public string Name { get; set; }

            public int CompareTo(object obj)
            {
                if (obj is LocodeEntry locodeEntry)
                    return Locode.CompareTo((locodeEntry).Locode);
                else
                    return 0;
            }
        }

        #endregion

    }
}