Dev (#28)

* Feature/ci (#18)

* test ci

* try to release on github

* deploy only in master

* beautify readme

* try to fix deploy in master only

* Feature/ci (#20)

* test

* test

* fix

* fix

* dont deploy in pr

* fix base url

* fix warnings

* update packages

* Bug/23 (#27)

* #23 add tests

* add matcher

* ignore rider files

* add more tests

* fix one case, break another

* fix #23

.gitignore

@@ -1,2 +1,3 @@
 # User files
 *.user
+.idea

Izzy.Web.Tests/Izzy.Web.Tests.csproj

@@ -1,4 +1,4 @@
-<Project Sdk="Microsoft.NET.Sdk">
+<Project Sdk="Microsoft.NET.Sdk">
 
   <PropertyGroup>
     <TargetFramework>netcoreapp2.2</TargetFramework>
@@ -7,13 +7,16 @@
   </PropertyGroup>
 
   <ItemGroup>
-    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="15.9.0" />
-    <PackageReference Include="xunit" Version="2.4.0" />
-    <PackageReference Include="xunit.runner.visualstudio" Version="2.4.0" />
+    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="16.0.1" />
+    <PackageReference Include="NHamcrest" Version="2.0.1" />
+    <PackageReference Include="NHamcrest.XUnit" Version="2.0.1" />
+    <PackageReference Include="xunit" Version="2.4.1" />
+    <PackageReference Include="xunit.runner.visualstudio" Version="2.4.1" />
+    <PackageReference Include="Microsoft.AspNetCore.App" />
   </ItemGroup>
 
-  <ItemGroup>
-    <ProjectReference Include="..\Izzy.Web\Izzy.Web.csproj" />
+  <ItemGroup>
+    <ProjectReference Include="..\Izzy.Web\Izzy.Web.csproj" />
   </ItemGroup>
 
 </Project>

Izzy.Web.Tests/Matchers/HasTransfer.cs

@@ -0,0 +1,40 @@
+using System.Collections.Generic;
+using System.Linq;
+using Izzy.Web.Model;
+using Newtonsoft.Json;
+using NHamcrest;
+using Xunit;
+
+namespace Izzy.Web.Tests.Matchers
+{
+    public class HasTransfer : IMatcher<List<Transfer>>
+    {
+        private Transfer _expected;
+
+        public HasTransfer(Transfer expected)
+        {
+            _expected = expected;
+        }
+
+        public void DescribeTo(IDescription description)
+        {
+            description.AppendText("From DescribeTo");
+        }
+
+        public bool Matches(List<Transfer> actual)
+        {
+            return actual
+                .Any(
+                    t =>
+                        t.From == _expected.From
+                        && t.To == _expected.To
+                        && t.Roubles == _expected.Roubles
+                );
+        }
+
+        public void DescribeMismatch(List<Transfer> item, IDescription description)
+        {
+            description.AppendText("From DescribeMismatch").AppendText(JsonConvert.SerializeObject(item));
+        }
+    }
+}

Izzy.Web.Tests/Receipts/OneMoreThanMiddle/ThreePersons.cs

@@ -0,0 +1,31 @@
+using System.Collections.Generic;
+using Izzy.Web.Model;
+using Izzy.Web.Tests.Matchers;
+using NHamcrest;
+using Xunit;
+
+namespace Izzy.Web.Tests.Receipts.OneMoreThanMiddle
+{
+    public class ThreePersons
+    {
+        [Fact]
+        public void Test()
+        {
+            // Act
+            var receipt = new Receipt(
+                new List<Person>{
+                    new Person("Alice", 100),
+                    new Person("Bob", 30),
+                    new Person("Carol", 20)
+                }
+            );
+
+            var transfers = receipt.Transfers();
+
+            // Assert
+            NHamcrest.XUnit.Assert.That(transfers, Is.OfLength(2));
+            NHamcrest.XUnit.Assert.That(transfers, new HasTransfer(new Transfer("Bob", "Alice", 20m)));
+            NHamcrest.XUnit.Assert.That(transfers, new HasTransfer(new Transfer("Carol", "Alice", 30m)));
+        }
+    }
+}

Izzy.Web.Tests/Receipts/OneMoreThanMiddle/TwoPersons.cs

@@ -0,0 +1,29 @@
+using System.Collections.Generic;
+using Izzy.Web.Model;
+using Izzy.Web.Tests.Matchers;
+using NHamcrest;
+using Xunit;
+
+namespace Izzy.Web.Tests.Receipts.OneMoreThanMiddle
+{
+    public class TwoPersons
+    {
+        [Fact]
+        public void Test1()
+        {
+            // Act
+            var receipt = new Receipt(
+                new List<Person>{
+                    new Person("Alice", 100),
+                    new Person("Bob", 0)
+                }
+            );
+
+            var transfers = receipt.Transfers();
+
+            // Assert
+            NHamcrest.XUnit.Assert.That(transfers, Is.OfLength(1));
+            NHamcrest.XUnit.Assert.That(transfers, new HasTransfer(new Transfer("Bob", "Alice", 50m)));
+        }
+    }
+}

Izzy.Web.Tests/Receipts/TwoMoreThanMiddle/FivePersons.cs

@@ -0,0 +1,35 @@
+using System.Collections.Generic;
+using Izzy.Web.Model;
+using Izzy.Web.Tests.Matchers;
+using NHamcrest;
+using Xunit;
+
+namespace Izzy.Web.Tests.Receipts.TwoMoreThanMiddle
+{
+    public class FivePerson
+    {
+        [Fact]
+        public void TwoMoreThanMiddle_Calculate_ValidTransfers()
+        {
+            // Act
+            var receipt = new Receipt(
+                new List<Person>{
+                    new Person("Alice", 6800),
+                    new Person("Bob", 2900),
+                    new Person("Carol", 1500),
+                    new Person("Dave", 6400),
+                    new Person("Eve", 100)
+                }
+            );
+
+            var transfers = receipt.Transfers();
+
+            // Assert
+            NHamcrest.XUnit.Assert.That(transfers, Is.OfLength(4));
+            NHamcrest.XUnit.Assert.That(transfers, new HasTransfer(new Transfer("Bob", "Dave", 640m)));
+            NHamcrest.XUnit.Assert.That(transfers, new HasTransfer(new Transfer("Eve", "Dave", 180m)));
+            NHamcrest.XUnit.Assert.That(transfers, new HasTransfer(new Transfer("Eve", "Alice", 3260m)));
+            NHamcrest.XUnit.Assert.That(transfers, new HasTransfer(new Transfer("Carol", "Dave", 2040m)));
+        }
+    }
+}

Izzy.Web.Tests/Receipts/TwoMoreThanMiddle/ThreePersons.cs

@@ -0,0 +1,32 @@
+using System.Collections.Generic;
+using Izzy.Web.Model;
+using Izzy.Web.Tests.Matchers;
+using NHamcrest;
+using Xunit;
+
+
+namespace Izzy.Web.Tests.Receipts.TwoMoreThanMiddle
+{
+    public class TwoMoreThanMiddleTests
+    {
+        [Fact]
+        public void TwoMoreThanMiddle_Calculate_ValidTransfers()
+        {
+            // Act
+            var receipt = new Receipt(
+                new List<Person>{
+                    new Person("Alice", 600),
+                    new Person("Bob", 1100),
+                    new Person("Carol", 0)
+                }
+            );
+
+            var transfers = receipt.Transfers();
+
+            // Assert
+            NHamcrest.XUnit.Assert.That(transfers, Is.OfLength(2));
+            NHamcrest.XUnit.Assert.That(transfers, new HasTransfer(new Transfer("Carol", "Alice", 33.33m)));
+            NHamcrest.XUnit.Assert.That(transfers, new HasTransfer(new Transfer("Carol", "Bob", 533.33m)));
+        }
+    }
+}

Izzy.Web/Model/Receipt.cs

@@ -17,22 +17,49 @@ public List<Transfer> Transfers()
         {
             var transfers = new List<Transfer>();
             var total = this._persons.Sum(p => p.Roubles);
-            var roublesPerOne = Decimal.Round(total / this._persons.Count(), 2);
-            var personsTop = this._persons
-                .OrderByDescending(p => p.Roubles);
-            var spender = personsTop.First();
-            var personsExceptSpender = personsTop.Skip(1);
-            foreach (var person in personsExceptSpender)
+            var middle = Decimal.Round(total / this._persons.Count(), 2);
+            var personsTop = this._persons.OrderByDescending(p => p.Roubles).ToList();
+            var moreThanMiddle = personsTop.Where(p => p.Roubles >= middle).ToList();
+            var lessThanMiddle = personsTop.Except(moreThanMiddle).ToList();
+            for (int i = 0; i < moreThanMiddle.Count; i++)
             {
-                transfers.Add(
-                    new DifferenceTransfer(
-                        person,
-                        spender,
-                        roublesPerOne - person.Roubles
-                    )
-                );
+                var spender = moreThanMiddle[i];
+                for (int j = lessThanMiddle.Count - 1; j >= 0; j--)
+                {
+                    if (spender.Roubles - middle != 0)
+                    {
+                        var debtor = lessThanMiddle[j];
+                        var debtorDiff = middle - debtor.Roubles;
+                        var spenderDiff = spender.Roubles - middle;
+                        if (debtorDiff > spenderDiff)
+                        {
+                            transfers.Add(new Transfer(debtor, spender, spenderDiff));
+                            debtor.Roubles += spenderDiff;
+                            spender.Roubles -= spenderDiff;
+                        }
+                        else
+                        {
+                            transfers.Add(new Transfer(debtor, spender, debtorDiff));
+                            debtor.Roubles += debtorDiff;
+                            spender.Roubles -= debtorDiff;
+                        }
+                    }
+                }
             }
+
             return transfers;
         }
+
+        private Decimal diff(Person debtor, Person spender, Decimal middle)
+        {
+            if (debtor.Roubles > spender.Roubles - middle)
+            {
+                return spender.Roubles - middle;
+            }
+            else
+            {
+                return debtor.Roubles;
+            }
+        }
     }
 }