namespace LaaProduction.Personalization.Repositories
{
    using LaaProduction.Personalization.Models;
    using LaaProduction.Personalization.Repositories.Interfaces;
    using LaaProduction.SQL.Interfaces;

    using System.Collections.Generic;
    using System.Data.SqlClient;
    using System.Linq;

    internal class RolesRepository : IRolesRepository
    {
        private readonly ISQLConnection sqlConnection;

        public RolesRepository(ISQLConnection sqlConnection)
            => this.sqlConnection = sqlConnection;

        public IEnumerable<Role> All()
            => this.sqlConnection
                .CreateCommand(@"
                    SELECT [Recht]
	                     , [MitarbeiterNr]
                      FROM [MitarbeiterRechte]")
                .ExecuteReader(x => new Role
                {
                    Name = x.GetString(),
                    EmployeeId = (short)x.GetInt()
                });

        public IEnumerable<string> All(short employeeId)
            => this.sqlConnection
                .CreateCommand($@"
                    SELECT DISTINCT [Recht]
                      FROM [MitarbeiterRechte]
                     WHERE [MitarbeiterNr] = @{nameof(employeeId)}")
                .SetParameter(nameof(employeeId), employeeId)
                .ExecuteReader(x => x.GetString());

        public void Delete(short employeeId)
            => this.sqlConnection
                .CreateCommand($@"
                    DELETE FROM [MitarbeiterRechte]
                     WHERE [MitarbeiterNr] = @{nameof(employeeId)}")
                .SetParameter(nameof(employeeId), employeeId)
                .ExecuteNonQuery();

        public void Insert(short employeeId, IEnumerable<string> roles) 
            => this.sqlConnection
                .CreateCommand($@"
                    INSERT INTO [MitarbeiterRechte] ([MitarbeiterNr], [Recht])
                    VALUES {string.Join(", ", roles.Select((x, i) => $"(@{nameof(employeeId)}, '{new SqlParameter(i.ToString(), x).SqlValue}')"))}")
                .SetParameter(nameof(employeeId), employeeId)
                .ExecuteNonQuery();

        public void Insert(string role, IEnumerable<short> employees)
            => this.sqlConnection
                .CreateCommand($@"
                    INSERT INTO [MitarbeiterRechte] ([MitarbeiterNr], [Recht])
                    VALUES {string.Join(", ", employees.Select((x, i) => $"('{new SqlParameter(i.ToString(), x).SqlValue}', @{nameof(role)})"))}")
                .SetParameter(nameof(role), role)
                .ExecuteNonQuery();

        public void Delete(string role)
            => this.sqlConnection
                .CreateCommand($@"
                    DELETE FROM [MitarbeiterRechte]
                     WHERE [Recht] = @{nameof(role)}")
                .SetParameter(nameof(role), role)
                .ExecuteNonQuery();

        public IEnumerable<KeyValuePair<int, int>> UsersRolesCount()
            => this.sqlConnection
                .CreateCommand($@"
                    SELECT DISTINCT 
                           [MitarbeiterNr]
                         , COUNT([Recht])
                      FROM [MitarbeiterRechte]
                     GROUP BY [MitarbeiterNr]")
                .ExecuteReader(x => new KeyValuePair<int, int>(x.GetInt(), x.GetInt()));
    }
}