// Copyright (C) 2003-2010 Xtensive LLC.

// All rights reserved.

// For conditions of distribution and use, see license.

// Created by: Alexander Nikolaev

// Created:    2009.10.10



using System;

using System.Linq;

using Xtensive.Core.Tuples;

using Xtensive.Storage.Internals;

using Xtensive.Storage.Internals.Prefetch;

using Xtensive.Storage.Model;

using NUnit.Framework;

using Xtensive.Storage.Providers;

using Xtensive.Storage.Tests.Storage.Prefetch.Model;



namespace Xtensive.Storage.Tests.Storage.Prefetch

{

  public static class PrefetchTestHelper

  {

    public static void AssertOnlyDefaultColumnsAreLoaded(Key key, TypeInfo type, Session session)

    {

      AssertOnlySpecifiedColumnsAreLoaded(key, type, session, IsFieldToBeLoadedByDefault);

    }



    public static void AssertOnlySpecifiedColumnsAreLoaded(Key key, TypeInfo type, Session session,

      Func<FieldInfo, bool> fieldSelector)

    {

      var state = session.EntityStateCache[key, true];

      var realType = state.Key.Type;

      Assert.IsTrue(realType.Equals(type) 

        || realType.GetAncestors().Contains(type) 

        || (type.IsInterface && realType.GetInterfaces(true).Contains(type)));

      var tuple = state.Tuple;

      Assert.IsNotNull(tuple);

      foreach (var field in type.Fields) {

        var isFieldSelected = false;

        if (!field.IsStructure)

          isFieldSelected = fieldSelector.Invoke(field);

        foreach (var column in field.Columns) {

          if (field.IsStructure)

            isFieldSelected = fieldSelector.Invoke(column.Field);

          var isAvailable = tuple.GetFieldState(type.Columns.IndexOf(column)).IsAvailable();

          if (isFieldSelected)

            Assert.IsTrue(isAvailable);

          else

            Assert.IsFalse(isAvailable);

        }

      }

    }



    public static bool IsFieldToBeLoadedByDefault(FieldInfo field)

    {

      return field.IsPrimaryKey || field.IsSystem || !field.IsLazyLoad && !field.IsEntitySet;

    }



    public static void AssertReferencedEntityIsLoaded(Key key, Session session, FieldInfo referencingField)

    {

      var state = session.EntityStateCache[key, true];

      var foreignKeyValue = referencingField.Association.ExtractForeignKey(state.Type, state.Tuple);

      var foreignKey = Key.Create(session.Domain, referencingField.Association.TargetType,

        TypeReferenceAccuracy.BaseType, foreignKeyValue);

      AssertOnlySpecifiedColumnsAreLoaded(foreignKey, referencingField.Association.TargetType,

        session, IsFieldToBeLoadedByDefault);

    }



    public static void AssertEntitySetIsFullyLoaded(Key ownerKey, FieldInfo referencingField,

      int expectedCount, Session session)

    {

      EntitySetState setState;

      session.Handler.TryGetEntitySetState(ownerKey, referencingField, out setState);

      Assert.IsTrue(setState.IsFullyLoaded);

      Assert.AreEqual(expectedCount, setState.TotalItemCount);

    }



    public static void FillDataBase(Domain domain)

    {

      using (var session = Session.Open(domain))

      using (var transactionScope = Transaction.Open()) {

        FillDataBase(session);

        transactionScope.Complete();

      }

    }



    internal static void InvokePrefetch(this PrefetchManager prefetchManager, Key key, TypeInfo type,

      params PrefetchFieldDescriptor[] descriptors)

    {

      prefetchManager.Prefetch(key, type, new FieldDescriptorCollection(descriptors));

    }



    public static void InvokePrefetch(this SessionHandler sessionHandler, Key key, TypeInfo type,

      params PrefetchFieldDescriptor[] descriptors)

    {

      sessionHandler.Prefetch(key, type, new FieldDescriptorCollection(descriptors));

    }



    public static void FillDataBase(Session session)

    {

      var customer1 = new Customer {Name = "Customer1", Age = 25, City = "A"};

      var customer2 = new Customer {Name = "Customer2", Age = 30, City = "B"};

      var supplier1 = new Supplier {Name = "Supplier1", Age = 27};

      var supplier2 = new Supplier {Name = "Supplier2", Age = 35};

      var employee1 = new Employee {Name = "Employee1"};

      var employee2 = new Employee {Name = "Employee2"};

      var product1 = new Product {Name = "Product1", Supplier = supplier1};

      var product2 = new Product {Name = "Product2", Supplier = supplier1};

      var product3 = new Product {Name = "Product3", Supplier = supplier2};

      var product4 = new Product {Name = "Product4", Supplier = supplier2};

      var order1 = new Order {Number = 1, Customer = customer1, Employee = employee1};

      var order1Detail1 = new OrderDetail {Order = order1, Product = product1, Count = 100};

      var order1Detail2 = new OrderDetail {Order = order1, Product = product2, Count = 200};

      var order1Detail3 = new OrderDetail {Order = order1, Product = product3, Count = 300};

      var order1Detail4 = new OrderDetail {Order = order1, Product = product4, Count = 400};

      var order2 = new Order {Number = 2, Customer = customer2, Employee = employee2};

      var order2Detail1 = new OrderDetail {Order = order2, Product = product3, Count = 300};

      var order2Detail2 = new OrderDetail {Order = order2, Product = product4, Count = 400};

      var order3 = new Order {Number = 3, Customer = customer1, Employee = employee1};

      var order3Detail1 = new OrderDetail {Order = order3, Product = product1, Count = 50};

      var order3Detail2 = new OrderDetail {Order = order3, Product = product4, Count = 200};

    }



    public static void CreateOfferContainer(Domain domain, out Key contaierKey, out Key book0Key,

      out Key bookShop0Key, out Key book1Key, out Key bookShop1Key)

    {

      using (Session.Open(domain))

      using (var tx = Transaction.Open()) {

        var book0 = new Book {Category = "abc", Title = new Title {Text = "title"}};

        book0Key = book0.Key;

        var bookShop0 = new BookShop {Name = "a"};

        bookShop0Key = bookShop0.Key;

        var offer0 = new Offer {Book = book0, BookShop = bookShop0, Number = 3};

        var book1 = new Book {Category = "abc", Title = new Title {Text = "title"}};

        book1Key = book1.Key;

        var bookShop1 = new BookShop {Name = "a"};

        bookShop1Key = bookShop1.Key;

        var offer1 = new Offer {Book = book1, BookShop = bookShop1, Number = 5};

        var intermediateOffer = new IntermediateOffer {RealOffer = offer1, Number = 15};

        contaierKey = new OfferContainer {

          RealOffer = offer0, IntermediateOffer = intermediateOffer, AuxField = "test"

        }.Key;

        tx.Complete();

      }

    }

  }

}