using System;
using System.Collections.Generic;
using System.Linq;

namespace Data_Import
{
    class Program
    {
        static void Main(string[] args)
        {
            var carContext = GetCarsFromCSV("data.csv").ToList();

            ExportCSVsByFuelType(carContext);

            var validCars = GetValidCars(carContext);
            Console.WriteLine("Valid Cars:\n");
            foreach(var c in validCars)
            {
                Console.WriteLine(c.AsCSV());
            }
            Console.WriteLine();

            var invalidCarCount = carContext.Count - validCars.Count();
            Console.WriteLine(String.Format("Invalid Car Count:\n{0}", invalidCarCount));
        }

        private static void ExportCSVsByFuelType(List<Car> cars)
        {
            //Could use a map here?
            List<string> petrolCars = new List<string>(), dieselCars = new List<string>();
            
            foreach (var c in cars)
            {
                if (c.FuelType == "Petrol")
                    petrolCars.Add(c.AsCSV());
                else if (c.FuelType == "Diesel")
                    dieselCars.Add(c.AsCSV());
            }

            CSVUtils.WriteCSV(petrolCars.ToArray(), "petrol.csv");
            CSVUtils.WriteCSV(dieselCars.ToArray(), "diesel.csv");
        }

        private static IEnumerable<Car> GetValidCars(List<Car> cars)
        {
            foreach (var car in cars)
            {
                if (car.HasValidRegistration())
                    yield return car;
            }
        }

        private static IEnumerable<Car> GetCarsFromCSV(string filename)
        {
            foreach(var carString in CSVUtils.ReadCSV(filename))
            {
                var c = new Car();
                yield return c.FromCSV(carString);
            }
        }
    }
}