namespace Aufgabe11
{
    public class SalesRepresentativeRepository
    {
        public List<(string FirstName, string LastName, string Company, decimal SalesVolume)>
            GetSalesRepsFromBadenWuerttemberg(List<SalesRepresentative> salesRepresentatives)
        {
            if (salesRepresentatives != null)
            {
                var results =
                    from representative in salesRepresentatives
                    where representative.Area == "Baden-Württemberg"
                    orderby representative.Company

                    select (FirstName: representative.FirstName,
                        LastName: representative.LastName,
                        Company: representative.Company,
                        SalesVolume: representative.SalesVolume);
                return results.ToList();
            }
            else
            {
                return new List<(string FirstName, string LastName, string Company, decimal SalesVolume)>();
            }
        }

        public List<SalesRepresentative> GetSalesRepsFromBadenWuerttembergNew(List<SalesRepresentative> salesRepresentatives)
        {
            if (salesRepresentatives != null)
            {
                var results =
                    from representative in salesRepresentatives
                    where representative.Area == "Baden-Württemberg"
                    orderby representative.Company

                    select representative;

                return results.ToList();
            }
            else
            {
                return new List<SalesRepresentative>();
            }
        }

        public List<(string FirstName, string LastName, string Company, string Area, decimal SalesVolume)>
            GetSalesRepsGroupedByCompany(List<SalesRepresentative> salesRepresentatives)
        {
            if (salesRepresentatives != null)
            {
                var results =
                    from representative in salesRepresentatives
                    where representative.SalesVolume >= 10000
                    orderby representative.Company, representative.SalesVolume descending

                    select (FirstName: representative.FirstName,
                        LastName: representative.LastName,
                        Company: representative.Company,
                        Area: representative.Area,
                        SalesVolume: representative.SalesVolume);

                return results.ToList();
            }
            else
            {
                return new List<(string FirstName, string LastName, string Company, string Area, decimal SalesVolume)>();
            }
        }

        public List<SalesRepresentative> GetSalesRepsGroupedByCompanyNew(List<SalesRepresentative> salesRepresentatives)
        {
            if (salesRepresentatives != null)
            {
                var results =
                    from representative in salesRepresentatives
                    where representative.SalesVolume >= 10000
                    orderby representative.Company, representative.SalesVolume descending

                    select representative;

                return results.ToList();
            }
            else
            {
                return new List<SalesRepresentative>();
            }
        }

        public List<(string FirstName, string LastName, string Company, string Area, decimal SalesVolume)>
            GetTopTenLosers(List<SalesRepresentative> salesRepresentatives)
        {
            if (salesRepresentatives != null)
            {
                var results =
                    from representative in salesRepresentatives
                    orderby representative.SalesVolume

                    select (FirstName: representative.FirstName,
                        LastName: representative.LastName,
                        Company: representative.Company,
                        Area: representative.Area,
                        SalesVolume: representative.SalesVolume);

                results = results.Take(10);

                return results.ToList();
            }
            else
            {
                return new List<(string FirstName, string LastName, string Company, string Area, decimal SalesVolume)>();
            }
        }

        public List<SalesRepresentative> GetTopTenLosersNew(List<SalesRepresentative> salesRepresentatives)
        {
            if (salesRepresentatives != null)
            {
                var results = salesRepresentatives
                    .OrderBy(representative => representative.SalesVolume)
                    .Take(10)
                    .ToList();

                return results;
            }
            else
            {
                return new List<SalesRepresentative>();
            }
        }
    }
}