Some fixes.

RentalBusiness/AuxilaryElements/BusinessLogic/BrandLogic.cs

@@ -0,0 +1,98 @@
+using Npgsql;
+using RentalBusiness.Models.ViewModels;
+
+namespace RentalBusiness.AuxilaryElements.BusinessLogic
+{
+    public class BrandLogic
+    {
+        public List<BrandViewModel> _brand;
+
+        public BrandLogic()
+        {
+            _brand = new();
+            _brand = ReadBrands().Result;
+        }
+
+        public async Task<List<BrandViewModel>> ReadBrands()
+        {
+            NpgsqlConnection connection = new NpgsqlConnection("Host=localhost;Database=local;Username=postgres;Password=postgres");
+            List<BrandViewModel> brands = new List<BrandViewModel>();
+            
+            
+            
+            connection.Open();
+
+
+            await using (NpgsqlCommand getRecordStorage = new NpgsqlCommand("SELECT brand_id, brand_name, brand_ratio FROM brand", connection))
+            {
+                await using (NpgsqlDataReader reader = await getRecordStorage.ExecuteReaderAsync())
+                {                  
+                    while (await reader.ReadAsync())
+                    {
+                        BrandViewModel viewModel = ReadModelView(reader);
+                        brands.Add(viewModel);
+                    }
+                }
+            }
+            connection.Close();
+          
+            return brands;
+
+        }
+
+        public BrandViewModel ReadModelView(NpgsqlDataReader reader)
+        {
+            int? id = reader["brand_id"] as int?;
+            string brandName = reader["brand_name"] as string;
+            int? ratio = reader["brand_ratio"] as int?;
+            BrandViewModel view = new BrandViewModel
+            {
+                ID = id.Value,
+                BrandName = new string(brandName),
+                BrandRatio = ratio.Value,
+            };
+            return view;
+        }
+
+        public void PostBrand(BrandViewModel view)
+        {
+            NpgsqlConnection connection = new NpgsqlConnection("Host=localhost;Database=local;Username=postgres;Password=postgres");
+            connection.Open();
+
+            using var checkDuplicate = new NpgsqlCommand("SELECT brand_id FROM brand WHERE brand_name LIKE @bn",connection)
+            {
+                Parameters =
+                {
+                    new("bn", view.BrandName)
+                }
+
+                
+            };
+
+            int? buff = Convert.ToInt32(checkDuplicate.ExecuteScalar());
+
+            if(buff == null)
+            {
+                return;
+            }
+
+            
+
+            using var postBrand = new NpgsqlCommand("INSERT INTO brand (brand_name,brand_ratio) VALUES(@bs,@br)",connection)
+            {
+                Parameters =
+                {
+                    new("bs",view.BrandName),
+                    new("br",view.BrandRatio)
+                }
+            };
+
+
+            postBrand.ExecuteNonQueryAsync();
+            
+
+            connection.Close();
+
+        }
+    }
+}

RentalBusiness/AuxilaryElements/BusinessLogic/ClientLogic.cs

@@ -0,0 +1,121 @@
+using Npgsql;
+using RentalBusiness.Enums;
+using RentalBusiness.Models.ViewModels;
+using static Microsoft.EntityFrameworkCore.DbLoggerCategory.Database;
+
+namespace RentalBusiness.AuxilaryElements.BusinessLogic
+{
+    public class ClientLogic
+    {
+        public List<ClientViewModel> _clients;
+
+        public ClientLogic()
+        {
+            _clients = new List<ClientViewModel>();
+            _clients = ReadClients().Result;
+        }
+        public async Task<List<ClientViewModel>> ReadClients()
+        {
+            NpgsqlConnection connection = new NpgsqlConnection("Host=localhost;Database=local;Username=postgres;Password=postgres");
+            List<ClientViewModel> clients = new List<ClientViewModel>();
+
+            
+            connection.Open();
+            await using (NpgsqlCommand getRecordStorage = new NpgsqlCommand("SELECT C.customer_id, C.last_name, C.first_name, C.middle_name, C.id_card " +
+                                                                            "FROM customer C ", connection))
+            {
+                await using (NpgsqlDataReader reader = await getRecordStorage.ExecuteReaderAsync())
+                {
+                    while (await reader.ReadAsync())
+                    {
+                        ClientViewModel viewModel = ReadClientView(reader);
+                        clients.Add(viewModel);
+                    }
+                }
+            }
+            connection.Close();
+           
+
+            return clients;
+        }
+
+        public ClientViewModel ReadClientView(NpgsqlDataReader reader)
+        {
+            int? id = reader["customer_id"] as int?;
+            string lastName = reader["last_name"] as string;
+            string firstName = reader["first_name"] as string;
+            string middleName = reader["middle_name"] as string;
+            string idcard = reader["id_card"] as string;
+
+            ClientViewModel view = new ClientViewModel
+            {
+                ID = id.Value,
+                FullName = new string(lastName + " " + firstName + " " + middleName),
+                IDCard = new string(idcard)
+            };
+            return view;
+        }
+
+        public void PostClient(ClientViewModel model)
+        {
+            List<string> NameParts = model.FullName.Split(' ').ToList();
+            NpgsqlConnection connection = new NpgsqlConnection("Host=localhost;Database=local;Username=postgres;Password=postgres");
+            connection.Open();
+
+
+            using var command = new NpgsqlCommand("INSERT INTO customer (last_name,first_name,middle_name,id_card) VALUES(@ln,@fn,@mn,@ic)", connection)
+            {
+                Parameters =
+                {
+                    new("ln",NameParts[1]),
+                    new("fn",NameParts[0]),
+                    new("mn",NameParts[2]),
+                    new("ic",model.IDCard)
+                }
+
+            };
+            command.ExecuteNonQueryAsync();
+
+            connection.Close();
+        }
+
+        public void UpdateClient(ClientViewModel model)
+        {
+            List<string> NameParts = model.FullName.Split(' ').ToList();
+            NpgsqlConnection connection = new NpgsqlConnection("Host=localhost;Database=local;Username=postgres;Password=postgres");
+            connection.Open();
+
+            using (var fcommand = new NpgsqlCommand("UPDATE customer SET first_name = @fn WHERE customer_id = @cid", connection))
+            {
+                fcommand.Parameters.AddWithValue("cid", model.ID);
+                fcommand.Parameters.AddWithValue("fn", NameParts[0]);   
+                fcommand.ExecuteNonQueryAsync();
+            };
+           
+
+            using (var lcommand = new NpgsqlCommand("UPDATE customer SET last_name = @ln WHERE customer_id = @cid", connection))
+            {
+                lcommand.Parameters.AddWithValue("cid", model.ID);
+                lcommand.Parameters.AddWithValue("ln", NameParts[1]);
+                lcommand.ExecuteNonQueryAsync();
+            };
+            
+
+            using (var mcommand = new NpgsqlCommand("UPDATE customer SET middle_name = @mn WHERE customer_id = @cid", connection))
+            {
+                mcommand.Parameters.AddWithValue("cid", model.ID);
+                mcommand.Parameters.AddWithValue("mn", NameParts[2]);
+                mcommand.ExecuteNonQueryAsync();
+            };
+            
+
+            using (var icommand = new NpgsqlCommand("UPDATE customer SET id_card = @ic WHERE customer_id = @cid", connection))
+            {
+                icommand.Parameters.AddWithValue("cid", model.ID);
+                icommand.Parameters.AddWithValue("ic", model.IDCard);
+                icommand.ExecuteNonQueryAsync();
+            };
+            connection.Close();
+        }
+    }
+}

RentalBusiness/AuxilaryElements/BusinessLogic/ComplicatedQueriesLogic.cs

@@ -0,0 +1,61 @@
+using Npgsql;
+using RentalBusiness.Models;
+using RentalBusiness.Models.ViewModels;
+using System.Text.RegularExpressions;
+
+namespace RentalBusiness.AuxilaryElements.BusinessLogic
+{
+    public class ComplicatedQueriesLogic
+    {
+        public List<TopCarViewModel> _topCars;
+
+        public ComplicatedQueriesLogic() 
+        {
+            _topCars = new List<TopCarViewModel>();
+            _topCars = ReadTopCars().Result;
+        }
+
+        public async Task<List<TopCarViewModel>> ReadTopCars()
+        {
+            List<TopCarViewModel> topCarViewModels = new List<TopCarViewModel>();
+            NpgsqlConnection connection = new NpgsqlConnection("Host=localhost;Database=local;Username=postgres;Password=postgres");
+            
+
+            connection.Open();
+          
+            await using (var getCars = new NpgsqlCommand("SELECT C.car_id,B.brand_name, M.model_spec, SUM(Price) AS Total, COUNT(*) AS Quantity FROM Contract C JOIN Storage S ON C.car_id = S.car_id JOIN Brand B ON B.brand_id = S.brand_id JOIN Model M ON M.model_id = S.model_id GROUP BY(C.car_id, B.brand_name, M.model_spec) ORDER BY 5 DESC", connection))
+            {
+                await using (var reader = await getCars.ExecuteReaderAsync())
+                {
+                    while(await reader.ReadAsync())
+                    {
+                        TopCarViewModel viewModel = ReadCar(reader);
+                        topCarViewModels.Add(viewModel);
+                    }
+                }
+            }
+            connection.Close();
+
+            return topCarViewModels;
+        }
+
+        public TopCarViewModel ReadCar(NpgsqlDataReader reader)
+        {
+            int? id = reader["car_id"] as int?;
+            string BrandName = reader["brand_name"] as string;
+            string ModelName = reader["model_spec"] as string;
+            decimal? total = reader["Total"] as decimal?;
+            int? qt = Convert.ToInt32(reader["Quantity"] as long?);
+
+            TopCarViewModel topCarViewModel = new()
+            {
+                ID = id.Value,
+                CarInfo = new string(BrandName + " " + ModelName),
+                TotalIncome = total.Value,
+                Quantity = qt.Value,
+            };
+
+            return topCarViewModel;
+        }
+    }
+}

RentalBusiness/AuxilaryElements/BusinessLogic/ContractLogic.cs

@@ -0,0 +1,173 @@
+using Npgsql;
+using RentalBusiness.Enums;
+using RentalBusiness.Models;
+using RentalBusiness.Models.ViewModels;
+using static Microsoft.EntityFrameworkCore.DbLoggerCategory.Database;
+using System.Diagnostics.Contracts;
+using Microsoft.EntityFrameworkCore.Query.Internal;
+
+namespace RentalBusiness.AuxilaryElements.BusinessLogic
+{
+    public class ContractLogic
+    {
+        public List<ContractViewModel> _contracts;
+
+        public ContractLogic()
+        {
+            _contracts = new List<ContractViewModel>();
+            _contracts = ReadContracts().Result;
+        }
+
+        public async Task<List<ContractViewModel>> ReadContracts()
+        {
+            NpgsqlConnection connection = new NpgsqlConnection("Host=localhost;Database=local;Username=postgres;Password=postgres");
+            List<ContractViewModel> contracts = new List<ContractViewModel>();
+            connection.Open();
+            await using (NpgsqlCommand getRecordStorage = new NpgsqlCommand("SELECT C.contract_id, C.car_id, B.brand_name, M.model_spec, C.customer_id, CS.first_name, CS.last_name, CS.id_card , C.rental_date, C.return_date, C.price, C.contract_status " +
+                                                                            "FROM contract C, brand B, model M, customer CS, storage S " +
+                                                                            "WHERE C.car_id = S.car_id AND S.brand_id = B.brand_id AND S.model_id = M.model_id AND C.customer_id = CS.customer_id", connection))
+            {
+                await using (NpgsqlDataReader reader = await getRecordStorage.ExecuteReaderAsync())
+                {
+                    while (await reader.ReadAsync())
+                    {
+                        ContractViewModel viewModel = ReadStorageView(reader);
+                        contracts.Add(viewModel);
+                    }
+                }
+            }
+            connection.Close();
+            return contracts;
+        }
+
+        public ContractViewModel ReadStorageView(NpgsqlDataReader reader)
+        {
+            int? contract_id = reader["contract_id"] as int?;
+            int? car_id = reader["car_id"] as int?;
+            string brandName = reader["brand_name"] as string;
+            string modelName = reader["model_spec"] as string;
+            int? customer_id = reader["customer_id"] as int?;
+            string firstname = reader["first_name"] as string;
+            string lastname = reader["last_name"] as string;
+            string idcard = reader["id_card"] as string;
+            DateTime? rental_date = reader["rental_date"] as DateTime?;
+            DateTime? return_date = reader["return_date"] as DateTime?;
+            decimal? price = reader["price"] as decimal?;
+            string contractStatus = reader["contract_status"] as string;
+
+            
+            ContractViewModel view = new ContractViewModel
+            {
+                ID = contract_id.Value,
+                CarID = car_id.Value,
+                CarInfo = new string(brandName + " " + modelName),
+                CustomerID = customer_id.Value,
+                CustomerFullName = new string(firstname + " " + lastname),
+                CustomerIDCard = new string(idcard),
+                CurDate = (DateTime)rental_date,
+                ReturnDate = (DateTime)return_date,
+                Price = price.Value,
+                Status = (ContractStatus)Enum.Parse(typeof(ContractStatus),contractStatus)
+            };
+
+            if(view.Status == ContractStatus.in_process)
+            {
+                ChangeContractStatus(view);
+            }
+            
+
+            return view;
+        }
+
+        public void PostContract(ContractViewModel contract)
+        {
+            NpgsqlConnection connection = new NpgsqlConnection("Host=localhost;Database=local;Username=postgres;Password=postgres");
+            connection.Open();
+
+            
+            using var command = new NpgsqlCommand("INSERT INTO contract (car_id,customer_id,rental_date,return_date,price,contract_status) VALUES(@caid,@cuid,@rend,@retd,@price,@cs)", connection)
+            {
+                Parameters =
+                {
+                    new("caid",contract.CarID),
+                    new("cuid",contract.CustomerID),
+                    new("rend",contract.CurDate),
+                    new("retd",contract.ReturnDate),
+                    new("price",contract.Price),
+                    new("cs",contract.Status)
+                }
+
+            };
+            command.ExecuteNonQueryAsync();
+
+            connection.Close();
+           
+
+            UpdateCarState(contract.CarID,contract.Status);
+        }
+
+        public void UpdateCarState(int carID, ContractStatus status)
+        {
+            NpgsqlConnection connection = new NpgsqlConnection("Host=localhost;Database=local;Username=postgres;Password=postgres");
+            connection.Open();
+            if (status == ContractStatus.in_process)
+            {
+                using (var carcommand = new NpgsqlCommand("UPDATE storage SET car_status = @cs WHERE car_id = @caid", connection))
+                {
+                    carcommand.Parameters.AddWithValue("caid", carID);
+                    carcommand.Parameters.AddWithValue("cs", CarStatus.is_taken);
+
+                    carcommand.ExecuteNonQueryAsync();
+                };
+            }
+            else
+            {
+                using (var carcommand = new NpgsqlCommand("UPDATE storage SET car_status = @cs WHERE car_id = @caid", connection))
+                {
+                    carcommand.Parameters.AddWithValue("caid", carID);
+                    carcommand.Parameters.AddWithValue("cs", CarStatus.available);
+
+                    carcommand.ExecuteNonQueryAsync();
+                };
+            }
+            
+            
+
+            connection.Close();
+        }
+
+        public void ChangeContractStatus(ContractViewModel model, bool flag = true)
+        {
+            DateTime curDate = DateTime.Today;
+            
+            if(model.ReturnDate.HasValue && DateTime.Compare(curDate, (DateTime)model.ReturnDate) < 0)
+            {
+                return;
+            }
+
+            if (flag)
+            {
+                model.Status = ContractStatus.expired;
+            }
+            else
+            {
+                model.Status = ContractStatus.finished;
+            }
+
+            NpgsqlConnection connection = new NpgsqlConnection("Host=localhost;Database=local;Username=postgres;Password=postgres");
+            connection.Open();
+            using (var contractStatusChange = new NpgsqlCommand("UPDATE contract SET contract_status = @cs WHERE contract_id = @caid", connection))
+            {
+                contractStatusChange.Parameters.AddWithValue("caid", model.ID);
+                contractStatusChange.Parameters.AddWithValue("cs", model.Status);
+
+                contractStatusChange.ExecuteNonQueryAsync();
+            };
+
+            connection.Close();
+
+            UpdateCarState(model.CarID, model.Status);
+        }
+       
+    }
+}

RentalBusiness/AuxilaryElements/BusinessLogic/ModelLogic.cs

@@ -0,0 +1,79 @@
+using Npgsql;
+using RentalBusiness.Enums;
+using RentalBusiness.Models.ViewModels;
+using static Microsoft.EntityFrameworkCore.DbLoggerCategory.Database;
+
+namespace RentalBusiness.AuxilaryElements.BusinessLogic
+{
+    public class ModelLogic
+    {
+        public List<ModelViewModel> _model;
+
+        public ModelLogic()
+        {
+            _model = new();
+            _model = ReadModels().Result;
+        }
+
+        public async Task<List<ModelViewModel>> ReadModels()
+        {
+            NpgsqlConnection connection = new NpgsqlConnection("Host=localhost;Database=local;Username=postgres;Password=postgres");
+            List<ModelViewModel> models = new List<ModelViewModel>();
+            
+            
+            connection.Open();
+           
+            await using (NpgsqlCommand getRecordStorage = new NpgsqlCommand("SELECT model_id, model_spec, model_ratio FROM model", connection))
+            {
+                await using (NpgsqlDataReader reader = await getRecordStorage.ExecuteReaderAsync())
+                {
+                    while (await reader.ReadAsync())
+                    {
+                        ModelViewModel viewModel = ReadModelView(reader);
+                        models.Add(viewModel);
+                    }
+                }
+            }
+            connection.Close();
+
+            return models;
+            
+        }
+
+        public ModelViewModel ReadModelView(NpgsqlDataReader reader)
+        {
+            int? id = reader["model_id"] as int?;
+            string modelSpec = reader["model_spec"] as string;
+            int? ratio = reader["model_ratio"] as int?;
+            ModelViewModel view = new ModelViewModel
+            {
+                ID = id.Value,
+                ModelSpec = new string(modelSpec),
+                ModelRatio = ratio.Value,
+            };
+            return view;
+        }
+
+        public void PostModel(ModelViewModel view)
+        {
+            NpgsqlConnection connection = new NpgsqlConnection("Host=localhost;Database=local;Username=postgres;Password=postgres");
+            connection.Open();
+
+           
+
+            using var postModel = new NpgsqlCommand("INSERT INTO model (model_spec,model_ratio) VALUES(@ms,@mr)",connection)
+            {
+                Parameters =
+                {
+                    new("ms",view.ModelSpec),
+                    new("mr",view.ModelRatio)
+                }
+            };
+
+            postModel.ExecuteNonQueryAsync();
+           
+            connection.Close();
+
+        }
+    }
+}

RentalBusiness/AuxilaryElements/BusinessLogic/SeedData.cs

@@ -0,0 +1,141 @@
+using Microsoft.EntityFrameworkCore;
+using Npgsql;
+using RentalBusiness.AuxilaryElements;
+using RentalBusiness.AuxilaryElements.Implements;
+using RentalBusiness.AuxilaryElements.ImplementsCars;
+using RentalBusiness.Enums;
+using RentalBusiness.Models.ViewModels;
+using System.Security.Cryptography.X509Certificates;
+using static Microsoft.EntityFrameworkCore.DbLoggerCategory.Database;
+
+namespace RentalBusiness.AuxilaryElements.BusinessLogic
+{
+    public static class SeedData
+    {
+        private static ICarBrand car;
+        static readonly List<ICarBrand> Brands = new()
+        {
+                { car = new Porsche()},
+                { car = new Tesla()},
+                { car = new Peugeot()},
+                { car = new Mazda()},
+                { car = new Kia()},
+                { car = new Jaguar()},
+                { car = new Honda()}
+        };
+
+        public static async Task InitializeBrands(NpgsqlConnection connection)
+        {
+            for (int i = 0; i < Brands.Count; i++)
+            {
+                car = Brands.ElementAt(i);
+                await using var command = new NpgsqlCommand("INSERT INTO brand (brand_name,brand_ratio) VALUES(@name,@ratio)", connection)
+                {
+                    Parameters =
+                    {
+                        new("name",car.Name),
+                        new("ratio",car.Ratio)
+                    }
+                };
+                await command.ExecuteNonQueryAsync();
+            }
+        }
+
+        public static async Task InitializeModels(NpgsqlConnection connection)
+        {
+            foreach (var brand in Brands)
+            {
+                foreach (var model in brand.Models)
+                {
+                    await using var command = new NpgsqlCommand("INSERT INTO model (model_spec,model_ratio) VALUES(@spec,@ratio)", connection)
+                    {
+                        Parameters =
+                        {
+                            new("spec",model.Name),
+                            new("ratio",model.Ratio)
+                        }
+
+                    };
+                    await command.ExecuteNonQueryAsync();
+                }
+
+            }
+        }
+
+        public static async Task InitializeCustomers(NpgsqlConnection connection)
+        {
+            List<string> firstName = new List<string> { "Ivanov", "Lisov", "Verner", "Antonov", "Reinvald", "Spotter", "Rein" };
+            List<string> lastName = new List<string> { "Nikita", "Artem", "Kirill", "Charlie", "Max", "Polie", "Mike", "El" };
+            List<string> middleName = new List<string> { "Andreevich", "Polynovich" };
+            var rnd = new Random();
+            for (int i = 0; i < 15; i++)
+            {
+                await using var command = new NpgsqlCommand("INSERT INTO customer (last_name,first_name,middle_name,id_card) VALUES(@ln,@fn,@mn,@ic)", connection)
+                {
+                    Parameters =
+                    {
+                        new("ln",lastName.ElementAt(rnd.Next(0,lastName.Count))),
+                        new("fn",firstName.ElementAt(rnd.Next(0,firstName.Count))),
+                        new("mn",middleName.ElementAt(rnd.Next(0,middleName.Count))),
+                        new("ic",rnd.Next(34678398,67806786).ToString())
+                    }
+
+                };
+                await command.ExecuteNonQueryAsync();
+            }
+        }
+
+        public static async Task InitializeCars(NpgsqlConnection connection)
+        {
+            int brandID = 0;
+            int modelID = 0;
+            foreach (var brand in Brands)
+            {
+                await using (var brandIDcommand = new NpgsqlCommand("SELECT brand_id FROM brand WHERE brand.brand_name = @bbn", connection))
+                {
+                    brandIDcommand.Parameters.AddWithValue("bbn", brand.Name);
+
+                    await using (NpgsqlDataReader reader = await brandIDcommand.ExecuteReaderAsync())
+                    {
+                        while (reader.Read())
+                        {
+                            brandID = Convert.ToInt32(reader[0].ToString());
+                        }
+                    }
+                };
+
+
+                foreach (var model in brand.Models)
+                {
+                    await using (var modelIDcommand = new NpgsqlCommand("SELECT model_id FROM model WHERE model.model_spec = @mmn", connection))
+                    {
+                        modelIDcommand.Parameters.AddWithValue("mmn", model.Name);
+
+                        await using (NpgsqlDataReader reader = await modelIDcommand.ExecuteReaderAsync())
+                        {
+                            while (reader.Read())
+                            {
+                                modelID = Convert.ToInt32(reader[0].ToString());
+                            }
+                        }
+                    };
+
+                    await using var command = new NpgsqlCommand("INSERT INTO storage (brand_id,model_id,car_ratio_per_hour,car_status) VALUES(@bid,@mid,@ratio,@status)", connection)
+                    {
+                        Parameters =
+                        {
+                            new("bid", brandID),
+                            new("mid", modelID),
+                            new("ratio",model.Ratio += brand.Ratio),
+                            new("status",CarStatus.available)
+                        }
+
+                    };
+                    await command.ExecuteNonQueryAsync();
+                }
+
+            }
+        }
+ 
+    }
+}

RentalBusiness/AuxilaryElements/BusinessLogic/StorageLogic.cs

@@ -0,0 +1,120 @@
+using Microsoft.EntityFrameworkCore.Metadata.Internal;
+using Npgsql;
+using RentalBusiness.Enums;
+using RentalBusiness.Models.ViewModels;
+
+namespace RentalBusiness.AuxilaryElements.BusinessLogic
+{
+    public class StorageLogic
+    {
+        public List<StorageViewModel> _storageFull;
+        public List<StorageViewModel> _storageFree;
+        public StorageLogic()
+        {
+            _storageFree = new List<StorageViewModel>();
+            _storageFree = ReadStorage(true).Result;
+            _storageFull = new List<StorageViewModel>();
+            _storageFull = ReadStorage(false).Result;
+        }
+
+        public async Task<List<StorageViewModel>> ReadStorage(bool flag = true)
+        {
+            NpgsqlConnection connection = new NpgsqlConnection("Host=localhost;Database=local;Username=postgres;Password=postgres");
+            List<StorageViewModel> cars = new List<StorageViewModel>();
+            connection.Open();
+            if(flag)
+            {
+                await using (NpgsqlCommand getRecordStorage = new NpgsqlCommand("SELECT S.car_id, B.brand_name, M.model_spec, S.car_ratio_per_hour, S.car_status " +
+                                                                            "FROM storage S, brand B, model M " +
+                                                                            "WHERE S.car_status = 'available' AND S.model_id = M.model_id " +
+                                                                            "AND S.brand_id = B.brand_id", connection))
+                {
+                    await using (NpgsqlDataReader reader = await getRecordStorage.ExecuteReaderAsync())
+                    {
+                        while (await reader.ReadAsync())
+                        {
+                            StorageViewModel viewModel = ReadStorageView(reader);
+                            cars.Add(viewModel);
+                        }
+                    }
+                }
+            }
+            else
+            {
+                await using (NpgsqlCommand getRecordStorage = new NpgsqlCommand("SELECT S.car_id, B.brand_name, M.model_spec, S.car_ratio_per_hour, S.car_status " +
+                                                                            "FROM storage S, brand B, model M " +
+                                                                            "WHERE S.model_id = M.model_id " +
+                                                                            "AND S.brand_id = B.brand_id", connection))
+                {
+                    await using (NpgsqlDataReader reader = await getRecordStorage.ExecuteReaderAsync())
+                    {
+                        while (await reader.ReadAsync())
+                        {
+                            StorageViewModel viewModel = ReadStorageView(reader);
+                            cars.Add(viewModel);
+                        }
+                    }
+                }
+            }
+            
+            connection.Close();
+
+            return cars;
+        }
+
+        public StorageViewModel ReadStorageView(NpgsqlDataReader reader)
+        {
+            int? id = reader["car_id"] as int?;
+            string brandName = reader["brand_name"] as string;
+            string modelName = reader["model_spec"] as string;
+            int? ratio = reader["car_ratio_per_hour"] as int?;
+            string carStatus = reader["car_status"] as string;
+            StorageViewModel view = new StorageViewModel
+            {
+                ID = id.Value,
+                CarInfo = new string(brandName + " " + modelName),
+                CarRatio = ratio.Value,
+                CarStatus = (CarStatus)Enum.Parse(typeof(CarStatus), carStatus)
+            };
+            return view;
+        }
+
+        public void PostCar(StorageViewModel model)
+        {
+            NpgsqlConnection connection = new NpgsqlConnection("Host=localhost;Database=local;Username=postgres;Password=postgres");
+            connection.Open();
+
+            using var checkDuplicate = new NpgsqlCommand("SELECT car_id FROM storage WHERE brand_id = @bid AND model_id = @mid", connection)
+            {
+                Parameters =
+                {
+                    new("bid",model.Brand_ID),
+                    new("mid",model.Model_ID),
+                }
+            };
+
+            int id = Convert.ToInt32(checkDuplicate.ExecuteScalar());
+
+            if(id != 0)
+            {
+                return;
+            }
+
+           
+            using var postCar = new NpgsqlCommand("INSERT INTO storage(brand_id,model_id,car_ratio_per_hour,car_status) VALUES(@bid,@mid,@ratio,@cs)", connection)
+            { 
+                Parameters = 
+                {
+                    new("bid",model.Brand_ID),
+                    new("mid",model.Model_ID),
+                    new("ratio",model.CarRatio),
+                    new("cs",model.CarStatus),
+                }
+            };
+
+            postCar.ExecuteNonQueryAsync();
+            
+            connection.Close();
+        }
+    }
+}

RentalBusiness/AuxilaryElements/CarModel.cs

@@ -0,0 +1,14 @@
+namespace RentalBusiness.AuxilaryElements
+{
+    public class CarModel : ICarModel
+    {
+        public string Name { get; set; }
+        public int Ratio { get; set; }
+
+        public CarModel(string Name, int Ratio)
+        {
+            this.Name = Name;
+            this.Ratio = Ratio;
+        }
+    }
+}

RentalBusiness/AuxilaryElements/ICarBrand.cs

@@ -0,0 +1,9 @@
+namespace RentalBusiness.AuxilaryElements
+{
+    public interface ICarBrand
+    {
+        public string Name { get; set; }
+        public int Ratio { get; set; }
+        public List<ICarModel> Models { get; set; }
+    }
+}

RentalBusiness/AuxilaryElements/ICarModel.cs

@@ -0,0 +1,8 @@
+namespace RentalBusiness.AuxilaryElements
+{
+    public interface ICarModel
+    {
+        public string Name { get; set; }
+        public int Ratio { get; set; }
+    }
+}

RentalBusiness/AuxilaryElements/ImplementsCars/Honda.cs

@@ -0,0 +1,25 @@
+namespace RentalBusiness.AuxilaryElements.ImplementsCars
+{
+    public class Honda : ICarBrand
+    {
+        public string Name { get; set; }
+        public List<ICarModel> Models { get; set; }
+        public int Ratio { get; set; }
+
+        Random rand = new Random();
+        public Honda()
+        {
+            Name = "Honda";
+            Ratio = rand.Next(2, 9);
+            Models = new List<ICarModel>
+            {
+                new CarModel("CR-V", rand.Next(2, 9)),
+                new CarModel("Civic", rand.Next(2, 9)),
+                new CarModel("HR-V", rand.Next(2, 9)),
+                new CarModel("Fit", rand.Next(2, 9)),
+                new CarModel("Accord", rand.Next(2, 9)),
+                new CarModel("Integra", rand.Next(2, 9))
+            };
+        }
+    }
+}

RentalBusiness/AuxilaryElements/ImplementsCars/Jaguar.cs

@@ -0,0 +1,24 @@
+namespace RentalBusiness.AuxilaryElements.ImplementsCars
+{
+    public class Jaguar : ICarBrand
+    {
+        public string Name { get; set; }
+        public List<ICarModel> Models { get; set; }
+        public int Ratio { get; set; }
+
+        Random rand = new Random();
+        public Jaguar()
+        {
+            Name = "Jaguar";
+            Ratio = rand.Next(2, 9);
+            Models = new List<ICarModel>
+            {
+                new CarModel("F-type", rand.Next(2, 9)),
+                new CarModel("F-PACE", rand.Next(2, 9)),
+                new CarModel("E-PACE", rand.Next(2, 9)),
+                new CarModel("XF", rand.Next(2, 9)),
+                new CarModel("I-PACE", rand.Next(2, 9))
+            };
+        }
+    }
+}

RentalBusiness/AuxilaryElements/ImplementsCars/Kia.cs

@@ -0,0 +1,27 @@
+namespace RentalBusiness.AuxilaryElements.ImplementsCars
+{
+    public class Kia : ICarBrand
+    {
+        public string Name { get; set; }
+        public List<ICarModel> Models { get; set; }
+        public int Ratio { get; set; }
+
+        Random rand = new Random();
+        public Kia()
+        {
+            Name = "Kia";
+            Ratio = rand.Next(2, 9);
+            Models = new List<ICarModel>
+            {
+                new CarModel("Sportage", rand.Next(2, 9)),
+                new CarModel("Sorento", rand.Next(2, 9)),
+                new CarModel("Rio", rand.Next(2, 9)),
+                new CarModel("Picanto", rand.Next(2, 9)),
+                new CarModel("Seltos", rand.Next(2, 9)),
+                new CarModel("Soul", rand.Next(2, 9)),
+                new CarModel("Carnival", rand.Next(2, 9)),
+                new CarModel("Cerato", rand.Next(2, 9))
+            };
+        }
+    }
+}

RentalBusiness/AuxilaryElements/ImplementsCars/Mazda.cs

@@ -0,0 +1,24 @@
+namespace RentalBusiness.AuxilaryElements.ImplementsCars
+{
+    public class Mazda  : ICarBrand
+    {
+        public string Name { get; set; }
+        public List<ICarModel> Models { get; set; }
+        public int Ratio { get; set; }
+
+        Random rand = new Random();
+        public Mazda()
+        {
+            Name = "Mazda";
+            Ratio = rand.Next(2, 9);
+            Models = new List<ICarModel>
+            {
+                new CarModel("F-A", rand.Next(2, 9)),
+                new CarModel("6", rand.Next(2, 9)),
+                new CarModel("8", rand.Next(2, 9)),
+                new CarModel("POL", rand.Next(2, 9)),
+                new CarModel("FGHJ", rand.Next(2, 9))
+            };
+        }
+    }
+}

RentalBusiness/AuxilaryElements/ImplementsCars/Peugeot.cs

@@ -0,0 +1,24 @@
+namespace RentalBusiness.AuxilaryElements.ImplementsCars
+{
+    public class Peugeot : ICarBrand
+    {
+        public string Name { get; set; }
+        public List<ICarModel> Models { get; set; }
+        public int Ratio { get; set; }
+
+        Random rand = new Random();
+        public Peugeot()
+        {
+            Name = "Peugeot";
+            Ratio = rand.Next(2, 9);
+            Models = new List<ICarModel>
+            {
+                new CarModel("3008", rand.Next(2, 9)),
+                new CarModel("2008", rand.Next(2, 9)),
+                new CarModel("408", rand.Next(2, 9)),
+                new CarModel("5008", rand.Next(2, 9)),
+                new CarModel("C504", rand.Next(2, 9))
+            };
+        }
+    }
+}

RentalBusiness/AuxilaryElements/ImplementsCars/Porsche.cs

@@ -0,0 +1,25 @@
+namespace RentalBusiness.AuxilaryElements.Implements
+{
+    public class Porsche : ICarBrand
+    {
+        public string Name { get; set; }
+        public List<ICarModel> Models {get; set;}
+        public int Ratio { get; set; }
+
+        Random rand = new Random();
+        public Porsche()
+        {            
+            Name = "Porsche";
+            Ratio = rand.Next(2,9);
+            Models = new List<ICarModel>
+            {
+                new CarModel("911", rand.Next(2, 9)),
+                new CarModel("718", rand.Next(2, 9)),
+                new CarModel("Cayman", rand.Next(2, 9)),
+                new CarModel("CarreraS", rand.Next(2, 9)),
+                new CarModel("Cayenne", rand.Next(2, 9)),
+                new CarModel("Taycan", rand.Next(2, 9))
+            };
+        }
+    }
+}

RentalBusiness/AuxilaryElements/ImplementsCars/Tesla.cs

@@ -0,0 +1,24 @@
+namespace RentalBusiness.AuxilaryElements.ImplementsCars
+{
+    public class Tesla : ICarBrand
+    {
+        public string Name { get; set; }
+        public List<ICarModel> Models { get; set; }
+        public int Ratio { get; set; }
+
+        Random rand = new Random();
+        public Tesla()
+        {
+            Name = "Tesla";
+            Ratio = rand.Next(2, 9);
+            Models = new List<ICarModel>
+            {
+                new CarModel("ModelS", rand.Next(2, 9)),
+                new CarModel("Model3", rand.Next(2, 9)),
+                new CarModel("ModelX", rand.Next(2, 9)),
+                new CarModel("ModelY", rand.Next(2, 9)),
+                new CarModel("Cybertruck", rand.Next(2, 9))
+            };
+        }
+    }
+}

RentalBusiness/Controllers/HomeController.cs

@@ -1,5 +1,8 @@
 using Microsoft.AspNetCore.Mvc;
+using RentalBusiness.AuxilaryElements.BusinessLogic;
+using RentalBusiness.Enums;
 using RentalBusiness.Models;
+using RentalBusiness.Models.ViewModels;
 using System.Diagnostics;
 
 namespace RentalBusiness.Controllers
@@ -7,26 +10,174 @@ namespace RentalBusiness.Controllers
     public class HomeController : Controller
     {
         private readonly ILogger<HomeController> _logger;
-
+        private readonly StorageLogic _storageLogic;
+        private readonly ClientLogic _clientLogic;
+        private readonly ContractLogic _contractLogic;
+        private readonly ModelLogic _modelLogic;
+        private readonly BrandLogic _brandLogic;
+        private readonly ComplicatedQueriesLogic _complicatedQueriesLogic;
         public HomeController(ILogger<HomeController> logger)
         {
             _logger = logger;
+            _storageLogic = new StorageLogic();
+            _clientLogic = new ClientLogic();
+            _contractLogic = new ContractLogic();
+            _modelLogic = new ModelLogic();
+            _brandLogic = new BrandLogic();
+            _complicatedQueriesLogic = new ComplicatedQueriesLogic();
         }
 
+        [HttpGet]
         public IActionResult Index()
         {
+            UpdateData();
+            ViewBag.Cars = _storageLogic._storageFree;
+            ViewBag.Clients = _clientLogic._clients;
             return View();
         }
 
-        public IActionResult Privacy()
+        [HttpPost]
+        public void Index(int car,int customer,string returnDate)
         {
+            ContractViewModel contract = new()
+            {
+                CarID = car,
+                CarInfo = _storageLogic._storageFull.First(x => x.ID == car).CarInfo,
+                CustomerID = customer,
+                CustomerFullName = _clientLogic._clients.First(x => x.ID == customer).FullName,
+                ReturnDate = DateTime.Parse(returnDate),
+                Price = Calc(car, returnDate)
+            };
+
+            _contractLogic.PostContract(contract);
+            Response.Redirect("Index");
+        }
+
+        [HttpGet]
+        public IActionResult Customer()
+        {
+            ViewBag.Clients = _clientLogic._clients;
             return View();
         }
 
+        [HttpPost]
+        public void Customer(int customer, string? fname, string? lname, string? mname, string? idcard, string funcbutton)
+        {
+            ClientViewModel client = new()
+            {
+                ID = customer,
+                FullName = new string(fname + " " + lname + " " + mname),
+                IDCard = new string(idcard)
+            };
+
+            if (funcbutton.Equals("Add"))
+            {
+                _clientLogic.PostClient(client);
+            }
+            else
+            {
+                _clientLogic.UpdateClient(client);
+            }
+            Response.Redirect("Index");
+        }
+
+        [HttpGet]
+        public IActionResult Car()
+        {
+            ViewBag.Models = _modelLogic._model;
+            ViewBag.Brands = _brandLogic._brand;
+            return View();
+        }
+
+        [HttpPost]
+        public void Car(string? brandname, int? brandratio, string? modelname, int? modelratio, int? brand, int? model )
+        {
+            if(!string.IsNullOrEmpty(brandname) && !string.IsNullOrEmpty(brandratio.ToString()))
+            {
+                BrandViewModel brandModel = new()
+                {
+                    BrandName = brandname,
+                    BrandRatio = brandratio
+                };
+
+                _brandLogic.PostBrand(brandModel);
+            }
+
+            if (!string.IsNullOrEmpty(modelname) && !string.IsNullOrEmpty(modelratio.ToString()))
+            {
+                ModelViewModel modelModel = new()
+                {
+                    ModelSpec = modelname,
+                    ModelRatio = modelratio
+                };
+
+                _modelLogic.PostModel(modelModel);
+                
+            }
+
+            if(brand != null && model != null)
+            {
+                StorageViewModel storageModel = new()
+                {
+                    Brand_ID = brand,
+                    Model_ID = model,
+                    CarRatio = _modelLogic._model.First(x => x.ID == model).ModelRatio + _brandLogic._brand.First(x => x.ID == brand).BrandRatio  
+                };
+
+                _storageLogic.PostCar(storageModel);
+            }           
+            Response.Redirect("Index");
+        }
+
+        [HttpGet]
+        public IActionResult Storage()
+        {
+            return View(_storageLogic._storageFull);
+        }
+
+        [HttpGet]
+        public IActionResult Contracts()
+        {
+            ViewBag.Contracts = _contractLogic._contracts.Where(contract => contract.Status != ContractStatus.finished).ToList();
+            return View(_contractLogic._contracts);
+        }
+
+        [HttpPost]
+        public void Contracts(int contract)
+        {
+            ContractViewModel model = new()
+            {
+                ID = contract,
+                CarID = _contractLogic._contracts.First(x => x.ID == contract).CarID,
+            };
+            _contractLogic.ChangeContractStatus(model, false);
+            Response.Redirect("Index");
+        }
+
+        [HttpGet]
+        public IActionResult TopCars() 
+        {
+            return View(_complicatedQueriesLogic._topCars);
+        }
+
         [ResponseCache(Duration = 0, Location = ResponseCacheLocation.None, NoStore = true)]
         public IActionResult Error()
         {
             return View(new ErrorViewModel { RequestId = Activity.Current?.Id ?? HttpContext.TraceIdentifier });
         }
+
+        [HttpPost]
+        public decimal Calc(int id, string date)
+        {
+            return (decimal)(_storageLogic._storageFull.First(x => x.ID == id).CarRatio * (Convert.ToInt32((DateTime.Parse(date) - DateTime.Now).TotalHours) * 5));
+        }
+
+        public void UpdateData()
+        {
+            _contractLogic._contracts = _contractLogic.ReadContracts().Result;
+            _storageLogic._storageFree = _storageLogic.ReadStorage(true).Result;
+            _storageLogic._storageFull = _storageLogic.ReadStorage(false).Result;
+            _clientLogic._clients = _clientLogic.ReadClients().Result;
+        }
     }
 }

RentalBusiness/Enums/CarStatus.cs

@@ -0,0 +1,9 @@
+
+namespace RentalBusiness.Enums
+{
+    public enum CarStatus
+    {
+        available, 
+        is_taken
+    }
+}

RentalBusiness/Enums/ContractStatus.cs

@@ -0,0 +1,9 @@
+namespace RentalBusiness.Enums
+{
+    public enum ContractStatus
+    {
+        in_process, 
+        finished, 
+        expired
+    }
+}

RentalBusiness/Migrations/20230402145704_EnumsCreation.Designer.cs

@@ -0,0 +1,316 @@
+// <auto-generated />
+using System;
+using Microsoft.EntityFrameworkCore;
+using Microsoft.EntityFrameworkCore.Infrastructure;
+using Microsoft.EntityFrameworkCore.Migrations;
+using Microsoft.EntityFrameworkCore.Storage.ValueConversion;
+using Npgsql.EntityFrameworkCore.PostgreSQL.Metadata;
+using RentalBusiness.Enums;
+using RentalBusiness.Models;
+
+#nullable disable
+
+namespace RentalBusiness.Migrations
+{
+    [DbContext(typeof(RentalbusinessContext))]
+    [Migration("20230402145704_EnumsCreation")]
+    partial class EnumsCreation
+    {
+        /// <inheritdoc />
+        protected override void BuildTargetModel(ModelBuilder modelBuilder)
+        {
+#pragma warning disable 612, 618
+            modelBuilder
+                .HasAnnotation("ProductVersion", "7.0.4")
+                .HasAnnotation("Relational:MaxIdentifierLength", 63);
+
+            NpgsqlModelBuilderExtensions.HasPostgresEnum(modelBuilder, "car_status", new[] { "available", "is_taken" });
+            NpgsqlModelBuilderExtensions.HasPostgresEnum(modelBuilder, "contract_status", new[] { "in_process", "finished", "expired" });
+            NpgsqlModelBuilderExtensions.UseIdentityByDefaultColumns(modelBuilder);
+
+            modelBuilder.Entity("RentalBusiness.Models.Brand", b =>
+                {
+                    b.Property<int>("BrandId")
+                        .ValueGeneratedOnAdd()
+                        .HasColumnType("integer")
+                        .HasColumnName("brand_id")
+                        .HasComment("Contains serial variable to identify each car brand.");
+
+                    NpgsqlPropertyBuilderExtensions.UseIdentityByDefaultColumn(b.Property<int>("BrandId"));
+
+                    b.Property<string>("BrandName")
+                        .IsRequired()
+                        .ValueGeneratedOnAdd()
+                        .HasMaxLength(255)
+                        .HasColumnType("character varying(255)")
+                        .HasColumnName("brand_name")
+                        .HasDefaultValueSql("'unknown'::character varying")
+                        .HasComment("Contains brand name  of car.");
+
+                    b.Property<int>("BrandRatio")
+                        .ValueGeneratedOnAdd()
+                        .HasColumnType("integer")
+                        .HasColumnName("brand_ratio")
+                        .HasDefaultValueSql("1")
+                        .HasComment("Contains ratio to calculate renting price.");
+
+                    b.HasKey("BrandId")
+                        .HasName("brand_pkey");
+
+                    b.ToTable("brand", null, t =>
+                        {
+                            t.HasComment("Contains info about existing brand names and their ratio for future renting price.");
+                        });
+                });
+
+            modelBuilder.Entity("RentalBusiness.Models.Contract", b =>
+                {
+                    b.Property<int>("ContractId")
+                        .ValueGeneratedOnAdd()
+                        .HasColumnType("integer")
+                        .HasColumnName("contract_id")
+                        .HasComment("Contains serial variable to identify each contract.");
+
+                    NpgsqlPropertyBuilderExtensions.UseIdentityByDefaultColumn(b.Property<int>("ContractId"));
+
+                    b.Property<int>("CarId")
+                        .HasColumnType("integer")
+                        .HasColumnName("car_id")
+                        .HasComment("Contains key which depicts a specific car from foreign table.");
+
+                    b.Property<int>("CustomerId")
+                        .HasColumnType("integer")
+                        .HasColumnName("customer_id")
+                        .HasComment("Contains key which depicts a specific customer from foreign table.");
+
+                    b.Property<decimal>("Price")
+                        .HasPrecision(10)
+                        .HasColumnType("numeric(10)")
+                        .HasColumnName("price")
+                        .HasComment("Contains a total cost of a contract from brand and model ration multiplying the length of rental date.");
+
+                    b.Property<DateTime>("RentalDate")
+                        .ValueGeneratedOnAdd()
+                        .HasColumnType("timestamp without time zone")
+                        .HasColumnName("rental_date")
+                        .HasDefaultValueSql("'1111-01-01 00:00:00'::timestamp without time zone")
+                        .HasComment("Contains info about start rental date.");
+
+                    b.Property<DateTime>("ReturnDate")
+                        .ValueGeneratedOnAdd()
+                        .HasColumnType("timestamp without time zone")
+                        .HasColumnName("return_date")
+                        .HasDefaultValueSql("'1111-01-01 00:00:00'::timestamp without time zone")
+                        .HasComment("Contains info about ending rental date.");
+
+                    b.Property<ContractStatus>("Status")
+                        .HasColumnType("contract_status");
+
+                    b.HasKey("ContractId")
+                        .HasName("contract_pkey");
+
+                    b.HasIndex("CarId");
+
+                    b.HasIndex("CustomerId");
+
+                    b.ToTable("contract", null, t =>
+                        {
+                            t.HasComment("Contains info about contracts which have ever been made.");
+                        });
+                });
+
+            modelBuilder.Entity("RentalBusiness.Models.Customer", b =>
+                {
+                    b.Property<int>("CustomerId")
+                        .ValueGeneratedOnAdd()
+                        .HasColumnType("integer")
+                        .HasColumnName("customer_id")
+                        .HasComment("Contains serial variable to identify each customer.");
+
+                    NpgsqlPropertyBuilderExtensions.UseIdentityByDefaultColumn(b.Property<int>("CustomerId"));
+
+                    b.Property<string>("FirstName")
+                        .IsRequired()
+                        .ValueGeneratedOnAdd()
+                        .HasMaxLength(255)
+                        .HasColumnType("character varying(255)")
+                        .HasColumnName("first_name")
+                        .HasDefaultValueSql("'unknown'::character varying")
+                        .HasComment("Contains first name of a customer.");
+
+                    b.Property<string>("IdCard")
+                        .IsRequired()
+                        .ValueGeneratedOnAdd()
+                        .HasMaxLength(255)
+                        .HasColumnType("character varying(255)")
+                        .HasColumnName("id_card")
+                        .HasDefaultValueSql("0")
+                        .HasComment("Contains id card digits.");
+
+                    b.Property<string>("LastName")
+                        .IsRequired()
+                        .ValueGeneratedOnAdd()
+                        .HasMaxLength(255)
+                        .HasColumnType("character varying(255)")
+                        .HasColumnName("last_name")
+                        .HasDefaultValueSql("'unknown'::character varying")
+                        .HasComment("Contains last name of a customer.");
+
+                    b.Property<string>("MiddleName")
+                        .ValueGeneratedOnAdd()
+                        .HasMaxLength(255)
+                        .HasColumnType("character varying(255)")
+                        .HasColumnName("middle_name")
+                        .HasDefaultValueSql("'unknown'::character varying")
+                        .HasComment("Contains(if exists) middle name of a customer.");
+
+                    b.HasKey("CustomerId")
+                        .HasName("customer_pkey");
+
+                    b.ToTable("customer", null, t =>
+                        {
+                            t.HasComment("Contains info about customer who have ever rented cars.");
+                        });
+                });
+
+            modelBuilder.Entity("RentalBusiness.Models.Model", b =>
+                {
+                    b.Property<int>("ModelId")
+                        .ValueGeneratedOnAdd()
+                        .HasColumnType("integer")
+                        .HasColumnName("model_id")
+                        .HasComment("Contains serial variable to identify each model specification.");
+
+                    NpgsqlPropertyBuilderExtensions.UseIdentityByDefaultColumn(b.Property<int>("ModelId"));
+
+                    b.Property<int>("ModelRatio")
+                        .ValueGeneratedOnAdd()
+                        .HasColumnType("integer")
+                        .HasColumnName("model_ratio")
+                        .HasDefaultValueSql("1")
+                        .HasComment("Contains ratio of model specification to calculate price of renting.");
+
+                    b.Property<string>("ModelSpec")
+                        .IsRequired()
+                        .ValueGeneratedOnAdd()
+                        .HasMaxLength(255)
+                        .HasColumnType("character varying(255)")
+                        .HasColumnName("model_spec")
+                        .HasDefaultValueSql("'unknown'::character varying")
+                        .HasComment("Contains name of model specification.");
+
+                    b.HasKey("ModelId")
+                        .HasName("model_pkey");
+
+                    b.ToTable("model", null, t =>
+                        {
+                            t.HasComment("Contains info about existing model specifications and ration for future calculation of renting price.");
+                        });
+                });
+
+            modelBuilder.Entity("RentalBusiness.Models.Storage", b =>
+                {
+                    b.Property<int>("CarId")
+                        .ValueGeneratedOnAdd()
+                        .HasColumnType("integer")
+                        .HasColumnName("car_id")
+                        .HasComment("Contains serial variable to identify each car.");
+
+                    NpgsqlPropertyBuilderExtensions.UseIdentityByDefaultColumn(b.Property<int>("CarId"));
+
+                    b.Property<int>("BrandId")
+                        .HasColumnType("integer")
+                        .HasColumnName("brand_id")
+                        .HasComment("Contains key from brand table which depicts brand.");
+
+                    b.Property<int>("CarRatioPerHour")
+                        .HasColumnType("integer")
+                        .HasColumnName("car_ratio_per_hour")
+                        .HasComment("Contains variable which consists of ratio from model and brand columns in foreign tables.");
+
+                    b.Property<int>("ModelId")
+                        .HasColumnType("integer")
+                        .HasColumnName("model_id")
+                        .HasComment("Contains key from model table which depicts model.");
+
+                    b.Property<CarStatus>("Status")
+                        .HasColumnType("car_status");
+
+                    b.HasKey("CarId")
+                        .HasName("storage_pkey");
+
+                    b.HasIndex("BrandId");
+
+                    b.HasIndex("ModelId");
+
+                    b.ToTable("storage", null, t =>
+                        {
+                            t.HasComment("Contains info about available cars for renting.");
+                        });
+                });
+
+            modelBuilder.Entity("RentalBusiness.Models.Contract", b =>
+                {
+                    b.HasOne("RentalBusiness.Models.Storage", "Car")
+                        .WithMany("Contracts")
+                        .HasForeignKey("CarId")
+                        .OnDelete(DeleteBehavior.Cascade)
+                        .IsRequired()
+                        .HasConstraintName("contract_storage_id_fkey");
+
+                    b.HasOne("RentalBusiness.Models.Customer", "Customer")
+                        .WithMany("Contracts")
+                        .HasForeignKey("CustomerId")
+                        .OnDelete(DeleteBehavior.Cascade)
+                        .IsRequired()
+                        .HasConstraintName("contract_customer_id_fkey");
+
+                    b.Navigation("Car");
+
+                    b.Navigation("Customer");
+                });
+
+            modelBuilder.Entity("RentalBusiness.Models.Storage", b =>
+                {
+                    b.HasOne("RentalBusiness.Models.Brand", "Brand")
+                        .WithMany("Storages")
+                        .HasForeignKey("BrandId")
+                        .OnDelete(DeleteBehavior.Cascade)
+                        .IsRequired()
+                        .HasConstraintName("storage_brand_id_fkey");
+
+                    b.HasOne("RentalBusiness.Models.Model", "Model")
+                        .WithMany("Storages")
+                        .HasForeignKey("ModelId")
+                        .OnDelete(DeleteBehavior.Cascade)
+                        .IsRequired()
+                        .HasConstraintName("storage_model_id_fkey");
+
+                    b.Navigation("Brand");
+
+                    b.Navigation("Model");
+                });
+
+            modelBuilder.Entity("RentalBusiness.Models.Brand", b =>
+                {
+                    b.Navigation("Storages");
+                });
+
+            modelBuilder.Entity("RentalBusiness.Models.Customer", b =>
+                {
+                    b.Navigation("Contracts");
+                });
+
+            modelBuilder.Entity("RentalBusiness.Models.Model", b =>
+                {
+                    b.Navigation("Storages");
+                });
+
+            modelBuilder.Entity("RentalBusiness.Models.Storage", b =>
+                {
+                    b.Navigation("Contracts");
+                });
+#pragma warning restore 612, 618
+        }
+    }
+}

RentalBusiness/Migrations/20230402145704_EnumsCreation.cs

@@ -0,0 +1,167 @@
+using System;
+using Microsoft.EntityFrameworkCore.Migrations;
+using Npgsql.EntityFrameworkCore.PostgreSQL.Metadata;
+using RentalBusiness.Enums;
+
+#nullable disable
+
+namespace RentalBusiness.Migrations
+{
+    /// <inheritdoc />
+    public partial class EnumsCreation : Migration
+    {
+        /// <inheritdoc />
+        protected override void Up(MigrationBuilder migrationBuilder)
+        {
+            migrationBuilder.AlterDatabase()
+                .Annotation("Npgsql:Enum:car_status", "available,is_taken")
+                .Annotation("Npgsql:Enum:contract_status", "in_process,finished,expired");
+
+            migrationBuilder.CreateTable(
+                name: "brand",
+                columns: table => new
+                {
+                    brand_id = table.Column<int>(type: "integer", nullable: false, comment: "Contains serial variable to identify each car brand.")
+                        .Annotation("Npgsql:ValueGenerationStrategy", NpgsqlValueGenerationStrategy.IdentityByDefaultColumn),
+                    brand_name = table.Column<string>(type: "character varying(255)", maxLength: 255, nullable: false, defaultValueSql: "'unknown'::character varying", comment: "Contains brand name  of car."),
+                    brand_ratio = table.Column<int>(type: "integer", nullable: false, defaultValueSql: "1", comment: "Contains ratio to calculate renting price.")
+                },
+                constraints: table =>
+                {
+                    table.PrimaryKey("brand_pkey", x => x.brand_id);
+                },
+                comment: "Contains info about existing brand names and their ratio for future renting price.");
+
+            migrationBuilder.CreateTable(
+                name: "customer",
+                columns: table => new
+                {
+                    customer_id = table.Column<int>(type: "integer", nullable: false, comment: "Contains serial variable to identify each customer.")
+                        .Annotation("Npgsql:ValueGenerationStrategy", NpgsqlValueGenerationStrategy.IdentityByDefaultColumn),
+                    last_name = table.Column<string>(type: "character varying(255)", maxLength: 255, nullable: false, defaultValueSql: "'unknown'::character varying", comment: "Contains last name of a customer."),
+                    first_name = table.Column<string>(type: "character varying(255)", maxLength: 255, nullable: false, defaultValueSql: "'unknown'::character varying", comment: "Contains first name of a customer."),
+                    middle_name = table.Column<string>(type: "character varying(255)", maxLength: 255, nullable: true, defaultValueSql: "'unknown'::character varying", comment: "Contains(if exists) middle name of a customer."),
+                    id_card = table.Column<string>(type: "character varying(255)", maxLength: 255, nullable: false, defaultValueSql: "0", comment: "Contains id card digits.")
+                },
+                constraints: table =>
+                {
+                    table.PrimaryKey("customer_pkey", x => x.customer_id);
+                },
+                comment: "Contains info about customer who have ever rented cars.");
+
+            migrationBuilder.CreateTable(
+                name: "model",
+                columns: table => new
+                {
+                    model_id = table.Column<int>(type: "integer", nullable: false, comment: "Contains serial variable to identify each model specification.")
+                        .Annotation("Npgsql:ValueGenerationStrategy", NpgsqlValueGenerationStrategy.IdentityByDefaultColumn),
+                    model_spec = table.Column<string>(type: "character varying(255)", maxLength: 255, nullable: false, defaultValueSql: "'unknown'::character varying", comment: "Contains name of model specification."),
+                    model_ratio = table.Column<int>(type: "integer", nullable: false, defaultValueSql: "1", comment: "Contains ratio of model specification to calculate price of renting.")
+                },
+                constraints: table =>
+                {
+                    table.PrimaryKey("model_pkey", x => x.model_id);
+                },
+                comment: "Contains info about existing model specifications and ration for future calculation of renting price.");
+
+            migrationBuilder.CreateTable(
+                name: "storage",
+                columns: table => new
+                {
+                    car_id = table.Column<int>(type: "integer", nullable: false, comment: "Contains serial variable to identify each car.")
+                        .Annotation("Npgsql:ValueGenerationStrategy", NpgsqlValueGenerationStrategy.IdentityByDefaultColumn),
+                    brand_id = table.Column<int>(type: "integer", nullable: false, comment: "Contains key from brand table which depicts brand."),
+                    model_id = table.Column<int>(type: "integer", nullable: false, comment: "Contains key from model table which depicts model."),
+                    car_ratio_per_hour = table.Column<int>(type: "integer", nullable: false, comment: "Contains variable which consists of ratio from model and brand columns in foreign tables."),
+                    car_status = table.Column<CarStatus>(type: "car_status", nullable: false, comment: "Contains the current state of car, whether it's available for rent or not.")
+                },
+                constraints: table =>
+                {
+                    table.PrimaryKey("storage_pkey", x => x.car_id);
+                    table.ForeignKey(
+                        name: "storage_brand_id_fkey",
+                        column: x => x.brand_id,
+                        principalTable: "brand",
+                        principalColumn: "brand_id",
+                        onDelete: ReferentialAction.Cascade);
+                    table.ForeignKey(
+                        name: "storage_model_id_fkey",
+                        column: x => x.model_id,
+                        principalTable: "model",
+                        principalColumn: "model_id",
+                        onDelete: ReferentialAction.Cascade);
+                },
+                comment: "Contains info about available cars for renting.");
+
+            migrationBuilder.CreateTable(
+                name: "contract",
+                columns: table => new
+                {
+                    contract_id = table.Column<int>(type: "integer", nullable: false, comment: "Contains serial variable to identify each contract.")
+                        .Annotation("Npgsql:ValueGenerationStrategy", NpgsqlValueGenerationStrategy.IdentityByDefaultColumn),
+                    car_id = table.Column<int>(type: "integer", nullable: false, comment: "Contains key which depicts a specific car from foreign table."),
+                    customer_id = table.Column<int>(type: "integer", nullable: false, comment: "Contains key which depicts a specific customer from foreign table."),
+                    rental_date = table.Column<DateTime>(type: "timestamp without time zone", nullable: false, defaultValueSql: "'1111-01-01 00:00:00'::timestamp without time zone", comment: "Contains info about start rental date."),
+                    return_date = table.Column<DateTime>(type: "timestamp without time zone", nullable: false, defaultValueSql: "'1111-01-01 00:00:00'::timestamp without time zone", comment: "Contains info about ending rental date."),
+                    price = table.Column<decimal>(type: "numeric(10)", precision: 10, nullable: false, comment: "Contains a total cost of a contract from brand and model ration multiplying the length of rental date."),
+                    contract_status = table.Column<ContractStatus>(type: "contract_status", nullable: false, comment: "Contains the current state of contract.")
+                },
+                constraints: table =>
+                {
+                    table.PrimaryKey("contract_pkey", x => x.contract_id);
+                    table.ForeignKey(
+                        name: "contract_customer_id_fkey",
+                        column: x => x.customer_id,
+                        principalTable: "customer",
+                        principalColumn: "customer_id",
+                        onDelete: ReferentialAction.Cascade);
+                    table.ForeignKey(
+                        name: "contract_storage_id_fkey",
+                        column: x => x.car_id,
+                        principalTable: "storage",
+                        principalColumn: "car_id",
+                        onDelete: ReferentialAction.Cascade);
+                },
+                comment: "Contains info about contracts which have ever been made.");
+
+            migrationBuilder.CreateIndex(
+                name: "IX_contract_car_id",
+                table: "contract",
+                column: "car_id");
+
+            migrationBuilder.CreateIndex(
+                name: "IX_contract_customer_id",
+                table: "contract",
+                column: "customer_id");
+
+            migrationBuilder.CreateIndex(
+                name: "IX_storage_brand_id",
+                table: "storage",
+                column: "brand_id");
+
+            migrationBuilder.CreateIndex(
+                name: "IX_storage_model_id",
+                table: "storage",
+                column: "model_id");
+        }
+
+        /// <inheritdoc />
+        protected override void Down(MigrationBuilder migrationBuilder)
+        {
+            migrationBuilder.DropTable(
+                name: "contract");
+
+            migrationBuilder.DropTable(
+                name: "customer");
+
+            migrationBuilder.DropTable(
+                name: "storage");
+
+            migrationBuilder.DropTable(
+                name: "brand");
+
+            migrationBuilder.DropTable(
+                name: "model");
+        }
+    }
+}

RentalBusiness/Migrations/RentalbusinessContextModelSnapshot.cs

@@ -0,0 +1,313 @@
+// <auto-generated />
+using System;
+using Microsoft.EntityFrameworkCore;
+using Microsoft.EntityFrameworkCore.Infrastructure;
+using Microsoft.EntityFrameworkCore.Storage.ValueConversion;
+using Npgsql.EntityFrameworkCore.PostgreSQL.Metadata;
+using RentalBusiness.Enums;
+using RentalBusiness.Models;
+
+#nullable disable
+
+namespace RentalBusiness.Migrations
+{
+    [DbContext(typeof(RentalbusinessContext))]
+    partial class RentalbusinessContextModelSnapshot : ModelSnapshot
+    {
+        protected override void BuildModel(ModelBuilder modelBuilder)
+        {
+#pragma warning disable 612, 618
+            modelBuilder
+                .HasAnnotation("ProductVersion", "7.0.4")
+                .HasAnnotation("Relational:MaxIdentifierLength", 63);
+
+            NpgsqlModelBuilderExtensions.HasPostgresEnum(modelBuilder, "car_status", new[] { "available", "is_taken" });
+            NpgsqlModelBuilderExtensions.HasPostgresEnum(modelBuilder, "contract_status", new[] { "in_process", "finished", "expired" });
+            NpgsqlModelBuilderExtensions.UseIdentityByDefaultColumns(modelBuilder);
+
+            modelBuilder.Entity("RentalBusiness.Models.Brand", b =>
+                {
+                    b.Property<int>("BrandId")
+                        .ValueGeneratedOnAdd()
+                        .HasColumnType("integer")
+                        .HasColumnName("brand_id")
+                        .HasComment("Contains serial variable to identify each car brand.");
+
+                    NpgsqlPropertyBuilderExtensions.UseIdentityByDefaultColumn(b.Property<int>("BrandId"));
+
+                    b.Property<string>("BrandName")
+                        .IsRequired()
+                        .ValueGeneratedOnAdd()
+                        .HasMaxLength(255)
+                        .HasColumnType("character varying(255)")
+                        .HasColumnName("brand_name")
+                        .HasDefaultValueSql("'unknown'::character varying")
+                        .HasComment("Contains brand name  of car.");
+
+                    b.Property<int>("BrandRatio")
+                        .ValueGeneratedOnAdd()
+                        .HasColumnType("integer")
+                        .HasColumnName("brand_ratio")
+                        .HasDefaultValueSql("1")
+                        .HasComment("Contains ratio to calculate renting price.");
+
+                    b.HasKey("BrandId")
+                        .HasName("brand_pkey");
+
+                    b.ToTable("brand", null, t =>
+                        {
+                            t.HasComment("Contains info about existing brand names and their ratio for future renting price.");
+                        });
+                });
+
+            modelBuilder.Entity("RentalBusiness.Models.Contract", b =>
+                {
+                    b.Property<int>("ContractId")
+                        .ValueGeneratedOnAdd()
+                        .HasColumnType("integer")
+                        .HasColumnName("contract_id")
+                        .HasComment("Contains serial variable to identify each contract.");
+
+                    NpgsqlPropertyBuilderExtensions.UseIdentityByDefaultColumn(b.Property<int>("ContractId"));
+
+                    b.Property<int>("CarId")
+                        .HasColumnType("integer")
+                        .HasColumnName("car_id")
+                        .HasComment("Contains key which depicts a specific car from foreign table.");
+
+                    b.Property<int>("CustomerId")
+                        .HasColumnType("integer")
+                        .HasColumnName("customer_id")
+                        .HasComment("Contains key which depicts a specific customer from foreign table.");
+
+                    b.Property<decimal>("Price")
+                        .HasPrecision(10)
+                        .HasColumnType("numeric(10)")
+                        .HasColumnName("price")
+                        .HasComment("Contains a total cost of a contract from brand and model ration multiplying the length of rental date.");
+
+                    b.Property<DateTime>("RentalDate")
+                        .ValueGeneratedOnAdd()
+                        .HasColumnType("timestamp without time zone")
+                        .HasColumnName("rental_date")
+                        .HasDefaultValueSql("'1111-01-01 00:00:00'::timestamp without time zone")
+                        .HasComment("Contains info about start rental date.");
+
+                    b.Property<DateTime>("ReturnDate")
+                        .ValueGeneratedOnAdd()
+                        .HasColumnType("timestamp without time zone")
+                        .HasColumnName("return_date")
+                        .HasDefaultValueSql("'1111-01-01 00:00:00'::timestamp without time zone")
+                        .HasComment("Contains info about ending rental date.");
+
+                    b.Property<ContractStatus>("Status")
+                        .HasColumnType("contract_status");
+
+                    b.HasKey("ContractId")
+                        .HasName("contract_pkey");
+
+                    b.HasIndex("CarId");
+
+                    b.HasIndex("CustomerId");
+
+                    b.ToTable("contract", null, t =>
+                        {
+                            t.HasComment("Contains info about contracts which have ever been made.");
+                        });
+                });
+
+            modelBuilder.Entity("RentalBusiness.Models.Customer", b =>
+                {
+                    b.Property<int>("CustomerId")
+                        .ValueGeneratedOnAdd()
+                        .HasColumnType("integer")
+                        .HasColumnName("customer_id")
+                        .HasComment("Contains serial variable to identify each customer.");
+
+                    NpgsqlPropertyBuilderExtensions.UseIdentityByDefaultColumn(b.Property<int>("CustomerId"));
+
+                    b.Property<string>("FirstName")
+                        .IsRequired()
+                        .ValueGeneratedOnAdd()
+                        .HasMaxLength(255)
+                        .HasColumnType("character varying(255)")
+                        .HasColumnName("first_name")
+                        .HasDefaultValueSql("'unknown'::character varying")
+                        .HasComment("Contains first name of a customer.");
+
+                    b.Property<string>("IdCard")
+                        .IsRequired()
+                        .ValueGeneratedOnAdd()
+                        .HasMaxLength(255)
+                        .HasColumnType("character varying(255)")
+                        .HasColumnName("id_card")
+                        .HasDefaultValueSql("0")
+                        .HasComment("Contains id card digits.");
+
+                    b.Property<string>("LastName")
+                        .IsRequired()
+                        .ValueGeneratedOnAdd()
+                        .HasMaxLength(255)
+                        .HasColumnType("character varying(255)")
+                        .HasColumnName("last_name")
+                        .HasDefaultValueSql("'unknown'::character varying")
+                        .HasComment("Contains last name of a customer.");
+
+                    b.Property<string>("MiddleName")
+                        .ValueGeneratedOnAdd()
+                        .HasMaxLength(255)
+                        .HasColumnType("character varying(255)")
+                        .HasColumnName("middle_name")
+                        .HasDefaultValueSql("'unknown'::character varying")
+                        .HasComment("Contains(if exists) middle name of a customer.");
+
+                    b.HasKey("CustomerId")
+                        .HasName("customer_pkey");
+
+                    b.ToTable("customer", null, t =>
+                        {
+                            t.HasComment("Contains info about customer who have ever rented cars.");
+                        });
+                });
+
+            modelBuilder.Entity("RentalBusiness.Models.Model", b =>
+                {
+                    b.Property<int>("ModelId")
+                        .ValueGeneratedOnAdd()
+                        .HasColumnType("integer")
+                        .HasColumnName("model_id")
+                        .HasComment("Contains serial variable to identify each model specification.");
+
+                    NpgsqlPropertyBuilderExtensions.UseIdentityByDefaultColumn(b.Property<int>("ModelId"));
+
+                    b.Property<int>("ModelRatio")
+                        .ValueGeneratedOnAdd()
+                        .HasColumnType("integer")
+                        .HasColumnName("model_ratio")
+                        .HasDefaultValueSql("1")
+                        .HasComment("Contains ratio of model specification to calculate price of renting.");
+
+                    b.Property<string>("ModelSpec")
+                        .IsRequired()
+                        .ValueGeneratedOnAdd()
+                        .HasMaxLength(255)
+                        .HasColumnType("character varying(255)")
+                        .HasColumnName("model_spec")
+                        .HasDefaultValueSql("'unknown'::character varying")
+                        .HasComment("Contains name of model specification.");
+
+                    b.HasKey("ModelId")
+                        .HasName("model_pkey");
+
+                    b.ToTable("model", null, t =>
+                        {
+                            t.HasComment("Contains info about existing model specifications and ration for future calculation of renting price.");
+                        });
+                });
+
+            modelBuilder.Entity("RentalBusiness.Models.Storage", b =>
+                {
+                    b.Property<int>("CarId")
+                        .ValueGeneratedOnAdd()
+                        .HasColumnType("integer")
+                        .HasColumnName("car_id")
+                        .HasComment("Contains serial variable to identify each car.");
+
+                    NpgsqlPropertyBuilderExtensions.UseIdentityByDefaultColumn(b.Property<int>("CarId"));
+
+                    b.Property<int>("BrandId")
+                        .HasColumnType("integer")
+                        .HasColumnName("brand_id")
+                        .HasComment("Contains key from brand table which depicts brand.");
+
+                    b.Property<int>("CarRatioPerHour")
+                        .HasColumnType("integer")
+                        .HasColumnName("car_ratio_per_hour")
+                        .HasComment("Contains variable which consists of ratio from model and brand columns in foreign tables.");
+
+                    b.Property<int>("ModelId")
+                        .HasColumnType("integer")
+                        .HasColumnName("model_id")
+                        .HasComment("Contains key from model table which depicts model.");
+
+                    b.Property<CarStatus>("Status")
+                        .HasColumnType("car_status");
+
+                    b.HasKey("CarId")
+                        .HasName("storage_pkey");
+
+                    b.HasIndex("BrandId");
+
+                    b.HasIndex("ModelId");
+
+                    b.ToTable("storage", null, t =>
+                        {
+                            t.HasComment("Contains info about available cars for renting.");
+                        });
+                });
+
+            modelBuilder.Entity("RentalBusiness.Models.Contract", b =>
+                {
+                    b.HasOne("RentalBusiness.Models.Storage", "Car")
+                        .WithMany("Contracts")
+                        .HasForeignKey("CarId")
+                        .OnDelete(DeleteBehavior.Cascade)
+                        .IsRequired()
+                        .HasConstraintName("contract_storage_id_fkey");
+
+                    b.HasOne("RentalBusiness.Models.Customer", "Customer")
+                        .WithMany("Contracts")
+                        .HasForeignKey("CustomerId")
+                        .OnDelete(DeleteBehavior.Cascade)
+                        .IsRequired()
+                        .HasConstraintName("contract_customer_id_fkey");
+
+                    b.Navigation("Car");
+
+                    b.Navigation("Customer");
+                });
+
+            modelBuilder.Entity("RentalBusiness.Models.Storage", b =>
+                {
+                    b.HasOne("RentalBusiness.Models.Brand", "Brand")
+                        .WithMany("Storages")
+                        .HasForeignKey("BrandId")
+                        .OnDelete(DeleteBehavior.Cascade)
+                        .IsRequired()
+                        .HasConstraintName("storage_brand_id_fkey");
+
+                    b.HasOne("RentalBusiness.Models.Model", "Model")
+                        .WithMany("Storages")
+                        .HasForeignKey("ModelId")
+                        .OnDelete(DeleteBehavior.Cascade)
+                        .IsRequired()
+                        .HasConstraintName("storage_model_id_fkey");
+
+                    b.Navigation("Brand");
+
+                    b.Navigation("Model");
+                });
+
+            modelBuilder.Entity("RentalBusiness.Models.Brand", b =>
+                {
+                    b.Navigation("Storages");
+                });
+
+            modelBuilder.Entity("RentalBusiness.Models.Customer", b =>
+                {
+                    b.Navigation("Contracts");
+                });
+
+            modelBuilder.Entity("RentalBusiness.Models.Model", b =>
+                {
+                    b.Navigation("Storages");
+                });
+
+            modelBuilder.Entity("RentalBusiness.Models.Storage", b =>
+                {
+                    b.Navigation("Contracts");
+                });
+#pragma warning restore 612, 618
+        }
+    }
+}

RentalBusiness/Models/Brand.cs

@@ -0,0 +1,27 @@
+using System;
+using System.Collections.Generic;
+
+namespace RentalBusiness.Models;
+
+/// <summary>
+/// Contains info about existing brand names and their ratio for future renting price.
+/// </summary>
+public partial class Brand
+{
+    /// <summary>
+    /// Contains serial variable to identify each car brand.
+    /// </summary>
+    public int BrandId { get; set; }
+
+    /// <summary>
+    /// Contains brand name  of car.
+    /// </summary>
+    public string BrandName { get; set; } = null!;
+
+    /// <summary>
+    /// Contains ratio to calculate renting price.
+    /// </summary>
+    public int BrandRatio { get; set; }
+
+    public virtual ICollection<Storage> Storages { get; } = new List<Storage>();
+}

RentalBusiness/Models/Contract.cs

@@ -0,0 +1,49 @@
+using RentalBusiness.Enums;
+using System;
+using System.Collections.Generic;
+
+namespace RentalBusiness.Models;
+
+/// <summary>
+/// Contains info about contracts which have ever been made.
+/// </summary>
+public partial class Contract
+{
+    /// <summary>
+    /// Contains serial variable to identify each contract.
+    /// </summary>
+    public int ContractId { get; set; }
+
+    /// <summary>
+    /// Contains key which depicts a specific car from foreign table.
+    /// </summary>
+    public int CarId { get; set; }
+
+    /// <summary>
+    /// Contains key which depicts a specific customer from foreign table.
+    /// </summary>
+    public int CustomerId { get; set; }
+
+    /// <summary>
+    /// Contains info about start rental date.
+    /// </summary>
+    public DateTime RentalDate { get; set; }
+
+    /// <summary>
+    /// Contains info about ending rental date.
+    /// </summary>
+    public DateTime ReturnDate { get; set; }
+
+    /// <summary>
+    /// Contains a total cost of a contract from brand and model ration multiplying the length of rental date.
+    /// </summary>
+    public decimal Price { get; set; }
+    /// <summary>
+    /// Contains a current state of contract.
+    /// </summary>
+    public ContractStatus Status { get; set; }
+
+    public virtual Storage Car { get; set; } = null!;
+
+    public virtual Customer Customer { get; set; } = null!;
+}

RentalBusiness/Models/Customer.cs

@@ -0,0 +1,37 @@
+using System;
+using System.Collections.Generic;
+
+namespace RentalBusiness.Models;
+
+/// <summary>
+/// Contains info about customer who have ever rented cars.
+/// </summary>
+public partial class Customer
+{
+    /// <summary>
+    /// Contains serial variable to identify each customer.
+    /// </summary>
+    public int CustomerId { get; set; }
+
+    /// <summary>
+    /// Contains last name of a customer.
+    /// </summary>
+    public string LastName { get; set; } = null!;
+
+    /// <summary>
+    /// Contains first name of a customer.
+    /// </summary>
+    public string FirstName { get; set; } = null!;
+
+    /// <summary>
+    /// Contains(if exists) middle name of a customer.
+    /// </summary>
+    public string? MiddleName { get; set; }
+
+    /// <summary>
+    /// Contains id card digits.
+    /// </summary>
+    public string IdCard { get; set; } = null!;
+
+    public virtual ICollection<Contract> Contracts { get; } = new List<Contract>();
+}

RentalBusiness/Models/Model.cs

@@ -0,0 +1,27 @@
+using System;
+using System.Collections.Generic;
+
+namespace RentalBusiness.Models;
+
+/// <summary>
+/// Contains info about existing model specifications and ration for future calculation of renting price.
+/// </summary>
+public partial class Model
+{
+    /// <summary>
+    /// Contains serial variable to identify each model specification.
+    /// </summary>
+    public int ModelId { get; set; }
+
+    /// <summary>
+    /// Contains name of model specification.
+    /// </summary>
+    public string ModelSpec { get; set; } = null!;
+
+    /// <summary>
+    /// Contains ratio of model specification to calculate price of renting.
+    /// </summary>
+    public int ModelRatio { get; set; }
+
+    public virtual ICollection<Storage> Storages { get; } = new List<Storage>();
+}

RentalBusiness/Models/RentalbusinessContext.cs

@@ -0,0 +1,184 @@
+using System;
+using System.Collections.Generic;
+using Microsoft.EntityFrameworkCore;
+using Npgsql;
+using RentalBusiness.Enums;
+
+namespace RentalBusiness.Models;
+
+public partial class RentalbusinessContext : DbContext
+{
+    public RentalbusinessContext()
+    {
+    }
+
+    public RentalbusinessContext(DbContextOptions<RentalbusinessContext> options)
+        : base(options)
+    {
+    }
+
+    public virtual DbSet<Brand> Brands { get; set; }
+
+    public virtual DbSet<Contract> Contracts { get; set; }
+
+    public virtual DbSet<Customer> Customers { get; set; }
+
+    public virtual DbSet<Model> Models { get; set; }
+
+    public virtual DbSet<Storage> Storages { get; set; }
+
+    static RentalbusinessContext()
+    {
+        
+    }
+    protected override void OnConfiguring(DbContextOptionsBuilder optionsBuilder) => optionsBuilder.UseNpgsql("Host=localhost;Port=5432;Database=local;Username=postgres;Password=postgres");
+
+    protected override void OnModelCreating(ModelBuilder modelBuilder)
+    {
+        modelBuilder
+            .HasPostgresEnum<CarStatus>()
+            .HasPostgresEnum<ContractStatus>();
+
+        modelBuilder.Entity<Brand>(entity =>
+        {
+            entity.HasKey(e => e.BrandId).HasName("brand_pkey");
+
+            entity.ToTable("brand", tb => tb.HasComment("Contains info about existing brand names and their ratio for future renting price."));
+
+            entity.Property(e => e.BrandId)
+                .HasComment("Contains serial variable to identify each car brand.")
+                .HasColumnName("brand_id");
+            entity.Property(e => e.BrandName)
+                .HasMaxLength(255)
+                .HasDefaultValueSql("'unknown'::character varying")
+                .HasComment("Contains brand name  of car.")
+                .HasColumnName("brand_name");
+            entity.Property(e => e.BrandRatio)
+                .HasDefaultValueSql("1")
+                .HasComment("Contains ratio to calculate renting price.")
+                .HasColumnName("brand_ratio");
+        });
+
+        modelBuilder.Entity<Contract>(entity =>
+        {
+            entity.HasKey(e => e.ContractId).HasName("contract_pkey");
+
+            entity.ToTable("contract", tb => tb.HasComment("Contains info about contracts which have ever been made."));
+
+            entity.Property(e => e.ContractId)
+                .HasComment("Contains serial variable to identify each contract.")
+                .HasColumnName("contract_id");
+            entity.Property(e => e.CarId)
+                .HasComment("Contains key which depicts a specific car from foreign table.")
+                .HasColumnName("car_id");
+            entity.Property(e => e.CustomerId)
+                .HasComment("Contains key which depicts a specific customer from foreign table.")
+                .HasColumnName("customer_id");
+            entity.Property(e => e.Price)
+                .HasPrecision(10)
+                .HasComment("Contains a total cost of a contract from brand and model ration multiplying the length of rental date.")
+                .HasColumnName("price");
+            entity.Property(e => e.RentalDate)
+                .HasDefaultValueSql("'1111-01-01 00:00:00'::timestamp without time zone")
+                .HasComment("Contains info about start rental date.")
+                .HasColumnType("timestamp without time zone")
+                .HasColumnName("rental_date");
+            entity.Property(e => e.ReturnDate)
+                .HasDefaultValueSql("'1111-01-01 00:00:00'::timestamp without time zone")
+                .HasComment("Contains info about ending rental date.")
+                .HasColumnType("timestamp without time zone")
+                .HasColumnName("return_date");
+
+            entity.HasOne(d => d.Car).WithMany(p => p.Contracts)
+                .HasForeignKey(d => d.CarId)
+                .HasConstraintName("contract_storage_id_fkey");
+
+            entity.HasOne(d => d.Customer).WithMany(p => p.Contracts)
+                .HasForeignKey(d => d.CustomerId)
+                .HasConstraintName("contract_customer_id_fkey");
+        });
+
+        modelBuilder.Entity<Customer>(entity =>
+        {
+            entity.HasKey(e => e.CustomerId).HasName("customer_pkey");
+
+            entity.ToTable("customer", tb => tb.HasComment("Contains info about customer who have ever rented cars."));
+
+            entity.Property(e => e.CustomerId)
+                .HasComment("Contains serial variable to identify each customer.")
+                .HasColumnName("customer_id");
+            entity.Property(e => e.FirstName)
+                .HasMaxLength(255)
+                .HasDefaultValueSql("'unknown'::character varying")
+                .HasComment("Contains first name of a customer.")
+                .HasColumnName("first_name");
+            entity.Property(e => e.IdCard)
+                .HasMaxLength(255)
+                .HasDefaultValueSql("0")
+                .HasComment("Contains id card digits.")
+                .HasColumnName("id_card");
+            entity.Property(e => e.LastName)
+                .HasMaxLength(255)
+                .HasDefaultValueSql("'unknown'::character varying")
+                .HasComment("Contains last name of a customer.")
+                .HasColumnName("last_name");
+            entity.Property(e => e.MiddleName)
+                .HasMaxLength(255)
+                .HasDefaultValueSql("'unknown'::character varying")
+                .HasComment("Contains(if exists) middle name of a customer.")
+                .HasColumnName("middle_name");
+        });
+
+        modelBuilder.Entity<Model>(entity =>
+        {
+            entity.HasKey(e => e.ModelId).HasName("model_pkey");
+
+            entity.ToTable("model", tb => tb.HasComment("Contains info about existing model specifications and ration for future calculation of renting price."));
+
+            entity.Property(e => e.ModelId)
+                .HasComment("Contains serial variable to identify each model specification.")
+                .HasColumnName("model_id");
+            entity.Property(e => e.ModelRatio)
+                .HasDefaultValueSql("1")
+                .HasComment("Contains ratio of model specification to calculate price of renting.")
+                .HasColumnName("model_ratio");
+            entity.Property(e => e.ModelSpec)
+                .HasMaxLength(255)
+                .HasDefaultValueSql("'unknown'::character varying")
+                .HasComment("Contains name of model specification.")
+                .HasColumnName("model_spec");
+        });
+
+        modelBuilder.Entity<Storage>(entity =>
+        {
+            entity.HasKey(e => e.CarId).HasName("storage_pkey");
+
+            entity.ToTable("storage", tb => tb.HasComment("Contains info about available cars for renting."));
+
+            entity.Property(e => e.CarId)
+                .HasComment("Contains serial variable to identify each car.")
+                .HasColumnName("car_id");
+            entity.Property(e => e.BrandId)
+                .HasComment("Contains key from brand table which depicts brand.")
+                .HasColumnName("brand_id");
+            entity.Property(e => e.CarRatioPerHour)
+                .HasComment("Contains variable which consists of ratio from model and brand columns in foreign tables.")
+                .HasColumnName("car_ratio_per_hour");
+            entity.Property(e => e.ModelId)
+                .HasComment("Contains key from model table which depicts model.")
+                .HasColumnName("model_id");
+
+            entity.HasOne(d => d.Brand).WithMany(p => p.Storages)
+                .HasForeignKey(d => d.BrandId)
+                .HasConstraintName("storage_brand_id_fkey");
+
+            entity.HasOne(d => d.Model).WithMany(p => p.Storages)
+                .HasForeignKey(d => d.ModelId)
+                .HasConstraintName("storage_model_id_fkey");
+        });
+
+        OnModelCreatingPartial(modelBuilder);
+    }
+
+    partial void OnModelCreatingPartial(ModelBuilder modelBuilder);
+}

RentalBusiness/Models/Storage.cs

@@ -0,0 +1,41 @@
+using RentalBusiness.Enums;
+using System;
+using System.Collections.Generic;
+
+namespace RentalBusiness.Models;
+
+/// <summary>
+/// Contains info about available cars for renting.
+/// </summary>
+public partial class Storage
+{
+    /// <summary>
+    /// Contains serial variable to identify each car.
+    /// </summary>
+    public int CarId { get; set; }
+
+    /// <summary>
+    /// Contains key from brand table which depicts brand.
+    /// </summary>
+    public int BrandId { get; set; }
+
+    /// <summary>
+    /// Contains key from model table which depicts model.
+    /// </summary>
+    public int ModelId { get; set; }
+
+    /// <summary>
+    /// Contains variable which consists of ratio from model and brand columns in foreign tables.
+    /// </summary>
+    public int CarRatioPerHour { get; set; }
+    /// <summary>
+    /// Contains a current state of car.
+    /// </summary>
+    public CarStatus Status { get; set; }
+
+    public virtual Brand Brand { get; set; } = null!;
+
+    public virtual ICollection<Contract> Contracts { get; } = new List<Contract>();
+
+    public virtual Model Model { get; set; } = null!;
+}

RentalBusiness/Models/ViewModels/BrandViewModel.cs

@@ -0,0 +1,9 @@
+namespace RentalBusiness.Models.ViewModels
+{
+    public class BrandViewModel
+    {
+        public int? ID { get; set; }
+        public string BrandName { get; set; } = string.Empty;
+        public int? BrandRatio { get; set; }
+    }
+}

RentalBusiness/Models/ViewModels/ClientViewModel.cs

@@ -0,0 +1,9 @@
+namespace RentalBusiness.Models.ViewModels
+{
+    public class ClientViewModel
+    {
+        public int ID { get; set; }
+        public string FullName { get; set; } = string.Empty;
+        public string IDCard { get; set; } = string.Empty;
+    }
+}

RentalBusiness/Models/ViewModels/ContractViewModel.cs

@@ -0,0 +1,18 @@
+using RentalBusiness.Enums;
+
+namespace RentalBusiness.Models.ViewModels
+{
+    public class ContractViewModel
+    {
+        public int? ID { get; set; }
+        public int CarID { get; set; }
+        public string CarInfo { get; set; } = string.Empty;
+        public int CustomerID { get; set; }
+        public string CustomerFullName { get; set; } = string.Empty;
+        public string CustomerIDCard { get; set; } = string.Empty;
+        public DateTime CurDate { get; set; } = DateTime.Now;
+        public DateTime? ReturnDate { get; set; }
+        public decimal Price { get; set; }
+        public ContractStatus Status { get; set; } = ContractStatus.in_process;
+    }
+}

RentalBusiness/Models/ViewModels/ModelViewModel.cs

@@ -0,0 +1,10 @@
+namespace RentalBusiness.Models.ViewModels
+{
+    public class ModelViewModel
+    {
+        public int? ID { get; set; }
+        public string ModelSpec { get; set; } = string.Empty;
+
+        public int? ModelRatio { get; set; }
+    }
+}

RentalBusiness/Models/ViewModels/StorageViewModel.cs

@@ -0,0 +1,17 @@
+using RentalBusiness.Enums;
+
+namespace RentalBusiness.Models.ViewModels
+{
+    public class StorageViewModel
+    {
+        public int ID { get; set; }
+        public string CarInfo { get; set; } = string.Empty;
+
+        public int? CarRatio { get; set; }
+
+        public CarStatus CarStatus { get; set; } = CarStatus.available;
+
+        public int? Brand_ID { get; set; }
+        public int? Model_ID { get; set; }
+    }
+}

RentalBusiness/Models/ViewModels/TopCarViewModel.cs

@@ -0,0 +1,10 @@
+namespace RentalBusiness.Models.ViewModels
+{
+    public class TopCarViewModel
+    {
+        public int ID { get; set; }
+        public string CarInfo { get; set; } = string.Empty;
+        public int Quantity { get; set; }
+        public decimal TotalIncome { get; set; }
+    }
+}

RentalBusiness/Program.cs

@@ -1,10 +1,37 @@
-var builder = WebApplication.CreateBuilder(args);
+using Microsoft.EntityFrameworkCore;
+using Npgsql;
+using RentalBusiness.AuxilaryElements.BusinessLogic;
+using RentalBusiness.Enums;
+using RentalBusiness.Models;
 
+var builder = WebApplication.CreateBuilder(args);
+var dataSourceBuilder = new NpgsqlDataSourceBuilder("Host=localhost;Database=local;Username=postgres;Password=postgres");
+dataSourceBuilder.MapEnum<CarStatus>();
+dataSourceBuilder.MapEnum<ContractStatus>();
+await using var dataSource = dataSourceBuilder.Build();
+await using var connection = await dataSource.OpenConnectionAsync();
 // Add services to the container.
 builder.Services.AddControllersWithViews();
+builder.Services.AddDbContext<RentalbusinessContext>(options => options.UseNpgsql(builder.Configuration.GetConnectionString("ASPDB")));
 
 var app = builder.Build();
 
+using (var scope = app.Services.CreateScope())
+{
+    var services = scope.ServiceProvider;
+    using (var context = new RentalbusinessContext(services.GetRequiredService<DbContextOptions<RentalbusinessContext>>()))
+    {
+        if(!context.Models.Any() && !context.Brands.Any() && !context.Customers.Any() && !context.Storages.Any())
+        {
+            await SeedData.InitializeBrands(connection);
+            await SeedData.InitializeModels(connection);
+            await SeedData.InitializeCustomers(connection);
+            await SeedData.InitializeCars(connection); 
+        }
+    }
+}
+
+
 // Configure the HTTP request pipeline.
 if (!app.Environment.IsDevelopment())
 {

RentalBusiness/RentalBusiness.csproj

@@ -6,4 +6,12 @@
     <ImplicitUsings>enable</ImplicitUsings>
   </PropertyGroup>
 
+  <ItemGroup>
+    <PackageReference Include="Microsoft.EntityFrameworkCore.Tools" Version="7.0.4">
+      <PrivateAssets>all</PrivateAssets>
+      <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
+    </PackageReference>
+    <PackageReference Include="Npgsql.EntityFrameworkCore.PostgreSQL" Version="7.0.3" />
+  </ItemGroup>
+
 </Project>

RentalBusiness/Views/Home/Car.cshtml

@@ -0,0 +1,51 @@
+@{
+    ViewData["Title"] = "Car";
+}
+<div class="text-center">
+    <h2 class="display-4">Add a car</h2>
+</div>
+<form method="post">
+    <div class="flex-container" style="flex-direction: row;  justify-content: space-between; display: flex; height: 100vh;">
+        <aside style="flex: 1"></aside>
+        <div class="flex-containerB1" style="flex-direction: column;  flex: 4; gap: 20px; display: flex; align-items: center; justify-content: center;">
+            <div class="brandtitle" style="text-align: center; font-size: 25px;">ADD A BRAND</div>
+            <div class="brandname" style="text-align: left; font-size: 15px;">Brand name:</div>
+            <input type="text" id="brandname" name="brandname" />
+            <div class="brandratio" style="text-align: left; font-size: 15px;">Brand ratio:</div>
+            <input type="text" id="brandratio" name="brandratio" />
+            <input type="submit" id="brandbtn" value="Brand" class="btn btn-primary" />
+        </div>
+        <aside style="flex: 1"></aside>
+        <div class="flex-containerB2" style="flex-direction: column;  flex: 4; gap: 20px;display: flex; align-items: center; justify-content: center;">
+            <div class="modeltitle" style="text-align: center; font-size: 25px;">ADD A MODEL</div>
+            <div class="modelname" style="text-align: left; font-size: 15px;">Model name:</div>
+            <input type="text" id="modelname" name="modelname" />
+            <div class="modelratio" style="text-align: left; font-size: 15px;">Model ratio:</div>
+            <input type="text" id="modelratio" name="modelratio" />
+            <input type="submit" id="modelbtn" value="Model" class="btn btn-primary" />
+        </div>
+        <aside style="flex: 1"></aside>
+        <div class="flex-containerB3" style="flex-direction: column; flex: 4; gap: 20px;display: flex; align-items: center; justify-content: center;">
+            <div class="brandtitle" style="text-align: center; font-size: 25px;">ADD A CAR</div>
+            <select id="brand" name="brand" class="form-control" asp-items="@(new SelectList(@ViewBag.Brands,"ID","BrandName"))"></select>
+            <select id="model" name="model" class="form-control" asp-items="@(new SelectList(@ViewBag.Models,"ID","ModelSpec"))"></select>
+            <input type="submit" id="carbtn" value="Car" class="btn btn-primary" />
+        </div>
+        <aside style="flex: 1"></aside>
+    </div>
+</form>
+<script>
+    $('#update').on('change', function () {
+        buttonchange();
+    });
+
+    function buttonchange() {
+        if (document.getElementById('update').checked) {
+            document.getElementById('funcbutton').value = "Update";
+        }
+        else
+        {
+            document.getElementById('funcbutton').value = "Add";
+        };
+    }
+</script>

RentalBusiness/Views/Home/Contracts.cshtml

@@ -0,0 +1,80 @@
+@using RentalBusiness.Models.ViewModels
+@model List<ContractViewModel>
+@{
+    ViewData["Title"] = "Contracts";
+}
+<div class="text-center">
+    <h1 class="display-4">Contracts</h1>
+</div>
+
+<div class="text-center">
+    @{
+        <table class="table">
+            <thead>
+                <tr>
+                    <th>
+                        ID
+                    </th>
+                    <th>
+                        Car
+                    </th>
+                    <th>
+                        Customer
+                    </th>
+                    <th>
+                        IDCard
+                    </th>
+                    <th>
+                        Creation date
+                    </th>
+                    <th>
+                        Return date
+                    </th>
+                    <th>
+                        Total
+                    </th>
+                    <th>
+                        Status
+                    </th>
+                </tr>
+            </thead>
+            <tbody>
+                @foreach (var item in Model)
+                {
+                    <tr>
+                        <td>
+                        @Html.DisplayFor(modelItem => item.ID)
+                        </td>
+                        <td>
+                            @Html.DisplayFor(modelItem => item.CarInfo)
+                        </td>
+                        <td>
+                            @Html.DisplayFor(modelItem => item.CustomerFullName)
+                        </td>
+                        <td>
+                            @Html.DisplayFor(modelItem => item.CustomerIDCard)
+                        </td>
+                        <td>
+                            @Html.DisplayFor(modelItem => item.CurDate)
+                        </td>
+                        <td>
+                            @Html.DisplayFor(modelItem => item.ReturnDate)
+                        </td>
+                        <td>
+                            @Html.DisplayFor(modelItem => item.Price)
+                        </td>
+                        <td>
+                            @Html.DisplayFor(modelItem => item.Status)
+                        </td>
+                    </tr>
+                }
+            </tbody>
+        </table>       
+    }
+    <form method="post">
+        <select id="contract" name="contract" class="form-control" asp-items="@(new SelectList(@ViewBag.Contracts,"ID","ID"))"></select>
+        <input type="submit" value="Finished" class="btn btn-primary" />
+    </form>
+    
+    
+</div>

RentalBusiness/Views/Home/Customer.cshtml

@@ -0,0 +1,47 @@
+@{
+    ViewData["Title"] = "Customer";
+}
+<div class="text-center">
+    <h2 class="display-4">Add/Update a customer</h2>
+</div>
+<form method="post">
+    <div class="row">
+        <div class="col-6">Customer:</div>
+        <div class="col-8"><select id="customer" name="customer" class="form-control" asp-items="@(new SelectList(@ViewBag.Clients,"ID","FullName"))"></select></div>
+    </div>
+    <div class="row">
+        <div class="col-6">FirstName:</div>
+        <div class="col-8"><input type="text" id="firstname" name="fname" /></div>
+    </div>
+    <div class="row">
+        <div class="col-6">LastName:</div>
+        <div class="col-8"><input type="text" id="lastname" name="lname" /></div>
+    </div>
+    <div class="row">
+        <div class="col-6">MiddleName:</div>
+        <div class="col-8"><input type="text" id="middlename" name="mname" /></div>
+    </div>
+    <div class="row">
+        <div class="col-6">IDCard:</div>
+        <div class="col-8"><input type="text" id="customercard" name="idcard" /></div>
+    </div>
+    <div class="row">
+        <div class="col-3"><input type="checkbox" id="update" name="update">
+            <label for="update">Update</label>
+        </div>
+        <div class="col-8"><input type="submit" id="funcbutton" name="funcbutton" value="Add" class="btn btn-primary" /></div>
+    </div>
+</form>
+<script>
+    $('#update').on('change', function () {
+        buttonchange();
+    });
+    function buttonchange() {
+        if (document.getElementById('update').checked) {
+            document.getElementById('funcbutton').value = "Update";
+        }
+        else {
+            document.getElementById('funcbutton').value = "Add";
+        };
+    }
+</script>

RentalBusiness/Views/Home/Index.cshtml

@@ -1,8 +1,60 @@
 @{
-    ViewData["Title"] = "Home Page";
+    ViewData["Title"] = "Rent";
 }
-
 <div class="text-center">
-    <h1 class="display-4">Welcome</h1>
-    <p>Learn about <a href="https://docs.microsoft.com/aspnet/core">building Web apps with ASP.NET Core</a>.</p>
+    <h2 class="display-4">Rent page</h2>
 </div>
+<form method="post">
+    <div class="row">
+        <div class="col-4">Car:</div>
+        <div class="col-8">
+            <select id="car" name="car" class="form-control" asp-items="@(new SelectList(@ViewBag.Cars,"ID","CarInfo"))"></select>
+        </div>
+    </div>
+    <div class="row">
+        <div class="col-4">Customer:</div>
+        <div class="col-8">
+            <select id="customer" name="customer" class="form-control" asp-items="@(new SelectList(@ViewBag.Clients,"ID","FullName"))"></select>
+        </div>
+    </div>
+    <div class="row">
+        <div class="col-4">ReturnDate:</div>
+        <div class="col-8">
+            <input type="date" id="returndate" name="returndate">
+        </div>
+    </div>
+    <div class="row">
+        <div class="col-4">Total:</div>
+        <div class="col-8"><input type="text" id="sum" name="sum" readonly /></div>
+    </div>
+    <div class="row">
+        <div class="col-8"></div>
+        <div class="col-4"><input type="submit" value="Create" class="btn btn-primary" /></div>
+    </div>
+</form>
+<script>
+    $('#car').on('change', function ()
+    {
+        check();
+    });
+    $('#returndate').on('change', function () {
+        check();
+    });
+
+    function check()
+    {
+        var car = $('#car').val();
+        var date = $('#returndate').val();
+        if (car && date) {
+            $.ajax({
+                method: "POST",
+                url: "/Home/Calc",
+                data: { id: car, date: date },
+                success: function (result)
+                {
+                    $("#sum").val(result);
+                }
+            });
+        };
+    }
+</script>

RentalBusiness/Views/Home/Storage.cshtml

@@ -0,0 +1,44 @@
+@using RentalBusiness.Models.ViewModels
+@model List<StorageViewModel>
+@{
+    ViewData["Title"] = "Storage";
+}
+<div class="text-center">
+    <h1 class="display-4">Storage</h1>
+</div>
+
+<div class="text-center">
+    @{
+        <table class="table">
+            <thead>
+                <tr>
+                    <th>
+                        Car
+                    </th>
+                    <th>
+                        Ratio
+                    </th>
+                    <th>
+                        Status
+                    </th>
+                </tr>
+            </thead>
+            <tbody>
+                @foreach (var item in Model)
+                {
+                    <tr>
+                        <td>
+                            @Html.DisplayFor(modelItem => item.CarInfo)
+                        </td>
+                        <td>
+                            @Html.DisplayFor(modelItem => item.CarRatio)
+                        </td>
+                        <td>
+                            @Html.DisplayFor(modelItem => item.CarStatus)
+                        </td>
+                    </tr>
+                }
+            </tbody>
+        </table>
+    }
+</div>

RentalBusiness/Views/Home/TopCars.cshtml

@@ -0,0 +1,43 @@
+@using RentalBusiness.Models.ViewModels
+@model List<TopCarViewModel>
+@{
+    ViewData["Title"] = "TopCars";
+}
+<div class="text-center">
+    <h2 class="display-4">The most profitable cars</h2>
+</div>
+<div class="text-center">
+    @{
+        <table class="table">
+            <thead>
+                <tr>
+                    <th>
+                        Car
+                    </th>
+                    <th>
+                        TotalIncome
+                    </th>
+                    <th>
+                        ContractsQuantity
+                    </th>                  
+                </tr>
+            </thead>
+            <tbody>
+                @foreach (var item in Model)
+                {
+                    <tr>
+                        <td>
+                            @Html.DisplayFor(modelItem => item.CarInfo)
+                        </td>
+                        <td>
+                            @Html.DisplayFor(modelItem => item.TotalIncome)
+                        </td>
+                        <td>
+                            @Html.DisplayFor(modelItem => item.Quantity)
+                        </td>                      
+                    </tr>
+                }
+            </tbody>
+        </table>
+    }  
+</div>

RentalBusiness/Views/Shared/_Layout.cshtml

@@ -3,27 +3,39 @@
 <head>
     <meta charset="utf-8" />
     <meta name="viewport" content="width=device-width, initial-scale=1.0" />
-    <title>@ViewData["Title"] - RentalBusiness</title>
+    <title>@ViewData["Title"] - EmployeeApp</title>
     <link rel="stylesheet" href="~/lib/bootstrap/dist/css/bootstrap.min.css" />
-    <link rel="stylesheet" href="~/css/site.css" asp-append-version="true" />
-    <link rel="stylesheet" href="~/RentalBusiness.styles.css" asp-append-version="true" />
+    <link rel="stylesheet" href="~/css/site.css" />
+    <script src="~/lib/jquery/dist/jquery.min.js"></script>
+    <script src="~/lib/bootstrap/dist/js/bootstrap.bundle.min.js"></script>
 </head>
 <body>
     <header>
-        <nav class="navbar navbar-expand-sm navbar-toggleable-sm navbar-light bg-white border-bottom box-shadow mb-3">
-            <div class="container-fluid">
-                <a class="navbar-brand" asp-area="" asp-controller="Home" asp-action="Index">RentalBusiness</a>
-                <button class="navbar-toggler" type="button" data-bs-toggle="collapse" data-bs-target=".navbar-collapse" aria-controls="navbarSupportedContent"
-                        aria-expanded="false" aria-label="Toggle navigation">
+        <nav class="navbar navbar-expand-sm navbar-toggleable-sm navbar-light bgwhite border-bottom box-shadow mb-3">
+            <div class="container">
+                <a class="navbar-brand" asp-area="" asp-controller="Home" aspaction="Index">Rental business</a>
+                <button class="navbar-toggler" type="button" datatoggle="collapse" data-target=".navbar-collapse" ariacontrols="navbarSupportedContent" aria-expanded="false" aria-label="Toggle navigation">
                     <span class="navbar-toggler-icon"></span>
                 </button>
-                <div class="navbar-collapse collapse d-sm-inline-flex justify-content-between">
+                <div class="navbar-collapse collapse d-sm-inline-flex flex-smrow-reverse">
                     <ul class="navbar-nav flex-grow-1">
                         <li class="nav-item">
-                            <a class="nav-link text-dark" asp-area="" asp-controller="Home" asp-action="Index">Home</a>
+                            <a class="nav-link text-dark" asparea="" asp-controller="Home" asp-action="TopCars">TOP CARS</a>
                         </li>
                         <li class="nav-item">
-                            <a class="nav-link text-dark" asp-area="" asp-controller="Home" asp-action="Privacy">Privacy</a>
+                            <a class="nav-link text-dark" asparea="" asp-controller="Home" asp-action="Storage">STORAGE</a>
+                        </li>
+                        <li class="nav-item">
+                            <a class="nav-link text-dark" asparea="" asp-controller="Home" asp-action="Contracts">CONTRACTS</a>
+                        </li>
+                        <li class="nav-item">
+                            <a class="nav-link text-dark" asparea="" asp-controller="Home" asp-action="Index">ADD CONTRACT</a>
+                        </li>
+                        <li class="nav-item">
+                            <a class="nav-link text-dark" asparea="" asp-controller="Home" asp-action="Car">ADD BRAND/MODEL/CAR</a>
+                        </li>
+                        <li class="nav-item">
+                            <a class="nav-link text-dark" asparea="" asp-controller="Home" asp-action="Customer">ADD CUSTOMER</a>
                         </li>
                     </ul>
                 </div>
@@ -35,15 +47,6 @@
             @RenderBody()
         </main>
     </div>
-
-    <footer class="border-top footer text-muted">
-        <div class="container">
-            &copy; 2023 - RentalBusiness - <a asp-area="" asp-controller="Home" asp-action="Privacy">Privacy</a>
-        </div>
-    </footer>
-    <script src="~/lib/jquery/dist/jquery.min.js"></script>
-    <script src="~/lib/bootstrap/dist/js/bootstrap.bundle.min.js"></script>
-    <script src="~/js/site.js" asp-append-version="true"></script>
-    @await RenderSectionAsync("Scripts", required: false)
+    <script src="~/js/site.js" asp-append-version="true"></script>     @RenderSection("Scripts", required: false)
 </body>
 </html> 

RentalBusiness/appsettings.json

@@ -5,5 +5,8 @@
       "Microsoft.AspNetCore": "Warning"
     }
   },
-  "AllowedHosts": "*"
+  "AllowedHosts": "*",
+  "ConnectionStrings": {
+    "ASPDB": "Host=localhost;Database=local;Username=postgres;Password=postgres"
+  }
 }