// Requires official C# and .NET MongoDB Driver 2.5+

using System;
using System.Collections.Generic;
using System.Globalization;
using System.IO;
using System.Text;
using System.Threading.Tasks;
using MongoDB.Bson;
using MongoDB.Driver;

namespace ConsoleApp1
{
    class Program
    {
        static async Task _Main()
        {

            IMongoClient client = new MongoClient("mongodb://localhost:27017/");
            IMongoDatabase database = client.GetDatabase("EmsIssuing");
            //IMongoCollection<BsonDocument> collection = database.GetCollection<BsonDocument>("BalanceHistory");

            // Created with Studio 3T, the IDE for MongoDB - https://studio3t.com/
            var fields = new HashSet<string>();
            fields.Add("_id");
            fields.Add("When");
            fields.Add("WalletId");
            fields.Add("CardId");
            fields.Add("MaskedPan");
            fields.Add("CardholderName");
            fields.Add("Description");
            fields.Add("TransactionType");
            fields.Add("LifeCycle");
            fields.Add("Source");
            fields.Add("TransactionRegion");
            fields.Add("Currency");
            fields.Add("Amount");
            fields.Add("Fee");
            fields.Add("AvailableBalance");
            fields.Add("LedgerBalance");

            // Created with Studio 3T, the IDE for MongoDB - https://studio3t.com/

            //var filter = RunFilter();
            int fromDate = 1, toDate = 2;
            GenerateCSV();

            void GenerateCSV()
        {
              var result = database.GetCollection<BsonDocument>("BalanceHistory").Find(RunFilter(31,1));
                var csv = new StringBuilder();
                string headerLine = string.Join(",", fields);

                csv.AppendLine(headerLine);

                foreach (var element in result.ToListAsync().Result)
                {
                    string line = null;
                    var counter = 0;
                    foreach (var field in fields)
                    {
                        counter++;
                        BsonValue value;

                        try
                        {
                            value = element.GetElement(field).Value;
                        }
                        catch (Exception e)
                        {
                            //todo add logging here
                            line = line + ",";
                            continue;
                        }

                        // Example deserialize to string
                        switch (value.BsonType)
                        {
                            case BsonType.ObjectId:
                            case BsonType.String:
                            case BsonType.DateTime:
                                line += value;
                                break;
                            case BsonType.Int32:
                                line += value.AsInt32;
                                break;
                            case BsonType.Int64:
                                line += value.AsInt64;
                                break;
                        }

                        if (counter != fields.Count)
                        {
                            line += ",";
                        }
                    }
                    csv.AppendLine(line);
                }

                var path = $"D:\\Temp\\Reports\\31";
                Directory.CreateDirectory(path);
                File.WriteAllText($"{path}\\EmsIssuing.BalanceHistory.csv", csv.ToString());
        }

        }

        public static BsonDocument RunFilter(int fromDate, int ToDate)
        {
            BsonDocument filter = new BsonDocument();
            filter.Add("$and", new BsonArray()
                .Add(new BsonDocument()
                    .Add("When", new BsonDocument()
                        .Add("$gte", new BsonDateTime(DateTime.ParseExact($"2019-07-{fromDate:D2} 01:00:00.000+0200", "yyyy-MM-dd HH:mm:ss.fffzzz", CultureInfo.InvariantCulture)))
                    )
                )
                .Add(new BsonDocument()
                    .Add("When", new BsonDocument()
                        .Add("$lt", new BsonDateTime(DateTime.ParseExact($"2019-08-{ToDate:D2} 01:00:00.000+0200", "yyyy-MM-dd HH:mm:ss.fffzzz", CultureInfo.InvariantCulture)))
                    )
                )
            );
            return filter;
        }



        static void Main(string[] args)
        {
            _Main().Wait();
        }
    }
}