Added proprietary user interface.

Added most game logic.

CleanTicTacToe/CleanTicTacToe.csproj

@@ -62,8 +62,6 @@
       <LastGenOutput>Resources.Designer.cs</LastGenOutput>
       <SubType>Designer</SubType>
     </EmbeddedResource>
-    <Compile Include="Properties\Grid.cs" />
-    <Compile Include="Properties\Player.cs" />
     <Compile Include="Properties\Resources.Designer.cs">
       <AutoGen>True</AutoGen>
       <DependentUpon>Resources.resx</DependentUpon>
@@ -81,5 +79,11 @@
   <ItemGroup>
     <None Include="App.config" />
   </ItemGroup>
+  <ItemGroup>
+    <ProjectReference Include="..\TicTacToe\TicTacToe.csproj">
+      <Project>{8EB373A9-D083-4BFE-9396-E9A40E75AAC2}</Project>
+      <Name>TicTacToe</Name>
+    </ProjectReference>
+  </ItemGroup>
   <Import Project="$(MSBuildToolsPath)\Microsoft.CSharp.targets" />
 </Project>

CleanTicTacToe/MainForm.Designer.cs

@@ -23,20 +23,46 @@
         /// Der Inhalt der Methode darf nicht mit dem Code-Editor geändert werden.
         /// </summary>
         private void InitializeComponent() {
+            this.statusStrip1 = new System.Windows.Forms.StatusStrip();
+            this.TslStatus = new System.Windows.Forms.ToolStripStatusLabel();
+            this.statusStrip1.SuspendLayout();
             this.SuspendLayout();
             // 
+            // statusStrip1
+            // 
+            this.statusStrip1.ImageScalingSize = new System.Drawing.Size(32, 32);
+            this.statusStrip1.Items.AddRange(new System.Windows.Forms.ToolStripItem[] {
+            this.TslStatus});
+            this.statusStrip1.Location = new System.Drawing.Point(0, 853);
+            this.statusStrip1.Name = "statusStrip1";
+            this.statusStrip1.Size = new System.Drawing.Size(1010, 38);
+            this.statusStrip1.TabIndex = 0;
+            this.statusStrip1.Text = "statusStrip1";
+            // 
+            // TslStatus
+            // 
+            this.TslStatus.Name = "TslStatus";
+            this.TslStatus.Size = new System.Drawing.Size(0, 28);
+            // 
             // MainForm
             // 
             this.AutoScaleDimensions = new System.Drawing.SizeF(12F, 25F);
             this.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Font;
             this.ClientSize = new System.Drawing.Size(1010, 891);
+            this.Controls.Add(this.statusStrip1);
             this.Name = "MainForm";
             this.Text = "Form1";
+            this.statusStrip1.ResumeLayout(false);
+            this.statusStrip1.PerformLayout();
             this.ResumeLayout(false);
+            this.PerformLayout();
 
         }
 
         #endregion
+
+        private System.Windows.Forms.StatusStrip statusStrip1;
+        private System.Windows.Forms.ToolStripStatusLabel TslStatus;
     }
 }
 

CleanTicTacToe/MainForm.cs

@@ -1,21 +1,59 @@
 using System;
-using System.Collections.Generic;
-using System.ComponentModel;
-using System.Data;
 using System.Drawing;
-using System.Linq;
-using System.Text;
-using System.Threading.Tasks;
 using System.Windows.Forms;
 using TicTacToe;
 
 namespace CleanTicTacToe {
     public partial class MainForm : Form {
+        private const int BUTTONSIZE = 100;
         private readonly Grid _grid;
-
+        private readonly Button[,] _pbxs = new Button[Grid.GRIDSIZE, Grid.GRIDSIZE];
         public MainForm() {
             InitializeComponent();
             _grid = new Grid();
+            _grid.ExpectNextTurn += Grid_ExpectNextTurn;
+            _grid.GameOver += Grid_GameOver;
+            for (var x = 0; x < Grid.GRIDSIZE; x++)
+                for (var y = 0; y < Grid.GRIDSIZE; y++) {
+                    var pictureBox = new Button() {
+                        Location = new Point(x * BUTTONSIZE, y * BUTTONSIZE),
+                        Width = BUTTONSIZE,
+                        Height = BUTTONSIZE,
+                        Tag = (x, y)
+                    };
+                    pictureBox.Click += Grid_Click;
+                    Controls.Add(pictureBox);
+                    _pbxs[x, y] = pictureBox;
+                }
+        }
+
+        private void Grid_GameOver(object sender, Player e) {
+            TslStatus.Text = $"Player {e} has won!";
+            _grid.Reset();
+        }
+
+        private void Grid_ExpectNextTurn(object sender, Player e) {
+            TslStatus.Text = $"Player {e} must now pick a spot!";
+        }
+
+        private void Grid_Click(object sender, EventArgs e) {
+            if (!(sender is Button pictureBox))
+                throw new InvalidProgramException("Expected picturebox as sender!");
+            (var x, var y) = ((int x, int y))pictureBox.Tag;
+            TslStatus.Text = $"Spot {x},{y} clicked!";
+            try {
+                _grid.PickSpot(x, y);
+            } catch (Exception ex) {
+                TslStatus.Text = ex.Message;
+            }
+            RefreshPbxs();
+        }
+
+        private void RefreshPbxs() {
+            for (var x = 0; x < Grid.GRIDSIZE; x++)
+                for (var y = 0; y < Grid.GRIDSIZE; y++) {
+                    _pbxs[x, y].Text = $"{Grid.GetPlayerChar(_grid[x, y])}";
+                }
         }
     }
 }

CleanTicTacToe/MainForm.resx

@@ -117,4 +117,7 @@
   <resheader name="writer">
     <value>System.Resources.ResXResourceWriter, System.Windows.Forms, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089</value>
   </resheader>
+  <metadata name="statusStrip1.TrayLocation" type="System.Drawing.Point, System.Drawing, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a">
+    <value>17, 17</value>
+  </metadata>
 </root>

CleanTicTacToe/Properties/Grid.cs

@@ -1,26 +0,0 @@
-namespace TicTacToe {
-    public class Grid {
-        private readonly Player[,] _field;
-        private const int GRIDSIZE = 3;
-        public bool GameOver => IsGameOver();
-
-        private bool IsGameOver() {
-            for (var x = 0; x < GRIDSIZE; x++)
-                for (var y = 0; y < GRIDSIZE; y++)
-                    if (IsFieldEmpty(x, y))
-                        return false;
-            return true;
-        }
-
-        private bool IsFieldEmpty(int x, int y) {
-            return _field[x, y] == Player.Empty;
-        }
-
-        public Grid() {
-            _field = new Player[GRIDSIZE, GRIDSIZE];
-        }
-
-        public bool PickSpot() {
-        }
-    }
-}

CleanTicTacToe/Properties/Player.cs

@@ -1,7 +0,0 @@
-namespace TicTacToe {
-    enum Player {
-        Empty = 0,
-        Cross = 1,
-        Circle = 2
-    }
-}

TicTacToe/Grid.cs

@@ -1,26 +1,299 @@
-namespace TicTacToe {
-    public class Grid {
-        private readonly Player[,] _field;
-        private const int GRIDSIZE = 3;
-        public bool GameOver => IsGameOver();
+using System;
+using System.Text;
 
-        private bool IsGameOver() {
-            for (var x = 0; x < GRIDSIZE; x++)
+namespace TicTacToe {
+    public class Grid {
+        public const int GRIDSIZE = 3;
+        private const Player GameBeginner = Player.Cross;
+        private Player NextGameBeginner = GameBeginner;
+        private readonly Player[,] _field = new Player[GRIDSIZE, GRIDSIZE];
+        private Player? winner;
+        private ((int x, int y) p1, (int x, int y) p2)? winningLine;
+        public event EventHandler<Player> ExpectNextTurn;
+        public event EventHandler<Player> GameOver;
+        public Player this[int x, int y] { get => _field[x, y]; }
+        public bool IsGameOver { get; private set; } = false;
+        public Player ActivePlayer { get; private set; } = GameBeginner;
+        public Player Winner { get => winner.Value; private set => winner = value; }
+        public ((int x, int y) p1, (int x, int y) p2) WinningLine { get => winningLine.Value; private set => winningLine = value; }
+        public Grid() {
+            Reset();
+        }
+        /// <summary>
+        /// Checks if a given field is empty.
+        /// </summary>
+        /// <param name="x">Column index</param>
+        /// <param name="y">Row index</param>
+        /// <returns>True if the field is empty</returns>
+        public bool IsEmpty(int x, int y) => _field[x, y] == Player.Empty;
+
+        public void Reset() {
+            ActivePlayer = NextGameBeginner;
+            NextGameBeginner = EnemyOf(NextGameBeginner);
+            IsGameOver = false;
+            winner = null;
+            winningLine = null;
             for (var y = 0; y < GRIDSIZE; y++)
-                    if (IsFieldEmpty(x, y))
+                for (var x = 0; x < GRIDSIZE; x++)
+                    _field[x, y] = Player.Empty;
+            ExpectNextTurn?.Invoke(this, ActivePlayer);
+        }
+
+        /// <summary>
+        /// Checks if a given field is not empty.
+        /// </summary>
+        /// <param name="x">Column index</param>
+        /// <param name="y">Row index</param>
+        /// <returns>True if the field is set</returns>
+        public bool IsSet(int x, int y) => _field[x, y] != Player.Empty;
+
+        public void PickSpot(int x, int y) {
+            if (IsGameOver)
+                throw new InvalidOperationException("Cannot pick spot on finished game!");
+            if (!IsEmpty(x, y))
+                throw new InvalidOperationException("Cannot pick already picked spot!");
+            _field[x, y] = ActivePlayer;
+            TurnOver();
+            if (!IsGameOver)
+                ExpectNextTurn?.Invoke(this, ActivePlayer);
+        }
+
+        /// <summary>
+        /// Tests if the game is over and updates the properties.
+        /// </summary>
+        /// <see cref="IsGameOver"/>
+        /// <see cref="Winner"/>
+        private void TurnOver() {
+            if (CheckRows() ||
+                CheckColumns() ||
+                CheckDiagonalPrimary() ||
+                CheckDiagonalSecondary() ||
+                CheckDraw()) { // Important to check after all other cases as there might be a full field with a winner
+                IsGameOver = true;
+                GameOver?.Invoke(this, Winner);
+            } else {
+                IsGameOver = false;
+                ActivePlayer = EnemyOf(ActivePlayer);
+            }
+        }
+
+        private static Player EnemyOf(Player player) {
+            switch (player) {
+            case Player.Cross:
+                return Player.Circle;
+            case Player.Circle:
+                return Player.Cross;
+            default:
+                throw new Exception("Unexpected enumerable state!");
+            }
+        }
+
+        #region GameOverTests
+        /// <summary>
+        /// Checks if a field is full and there is no winner
+        /// </summary>
+        /// <returns></returns>
+        private bool CheckDraw() {
+            for (var y = 0; y < GRIDSIZE; y++) {
+                for (var x = 0; x < GRIDSIZE; x++) {
+                    if (IsEmpty(x, y))
                         return false;
+                }
+            }
+            Winner = Player.Empty;
             return true;
         }
-
-        private bool IsFieldEmpty(int x, int y) {
-            return _field[x, y] == Player.Empty;
+        /// <summary>
+        /// Checks primary diagonal on a win.
+        /// </summary>
+        /// <returns>True if a win was found</returns>
+        private bool CheckDiagonalPrimary() {
+            var circlecount = 0;
+            var crosscount = 0;
+            for (var x = 0; x < GRIDSIZE; x++) {
+                switch (_field[x, x]) {
+                case Player.Circle:
+                    circlecount++;
+                    break;
+                case Player.Cross:
+                    crosscount++;
+                    break;
+                case Player.Empty:
+                    return false;
+                default:
+                    throw new InvalidProgramException("Unexpected enumerable state!");
+                }
+            }
+            if (crosscount == GRIDSIZE) {
+                Winner = Player.Cross;
+                WinningLine = ((0, 0), (GRIDSIZE, GRIDSIZE));
+                return true;
+            }
+            if (circlecount == GRIDSIZE) {
+                Winner = Player.Circle;
+                WinningLine = ((0, 0), (GRIDSIZE, GRIDSIZE));
+                return true;
+            }
+            return false;
+        }
+        /// <summary>
+        /// Checks secondary diagonal on a win.
+        /// </summary>
+        /// <returns>True if a win was found</returns>
+        private bool CheckDiagonalSecondary() {
+            var circlecount = 0;
+            var crosscount = 0;
+            for (var x = 0; x < GRIDSIZE; x++) {
+                switch (_field[x, GRIDSIZE - 1 - x]) {
+                case Player.Circle:
+                    circlecount++;
+                    break;
+                case Player.Cross:
+                    crosscount++;
+                    break;
+                case Player.Empty:
+                    return false;
+                default:
+                    throw new InvalidProgramException("Unexpected enumerable state!");
+                }
+            }
+            if (crosscount == GRIDSIZE) {
+                Winner = Player.Cross;
+                WinningLine = ((0, GRIDSIZE), (GRIDSIZE, 0));
+                return true;
+            }
+            if (circlecount == GRIDSIZE) {
+                Winner = Player.Circle;
+                WinningLine = ((0, GRIDSIZE), (GRIDSIZE, 0));
+                return true;
+            }
+            return false;
         }
 
-        public Grid() {
-            _field = new Player[GRIDSIZE, GRIDSIZE];
+        /// <summary>
+        /// Checks all columns on a win.
+        /// </summary>
+        /// <returns>True if a win was found</returns>
+        private bool CheckColumns() {
+            for (var x = 0; x < GRIDSIZE; x++) {
+                if (CheckColumn(in x)) {
+                    WinningLine = ((x, 0), (x, GRIDSIZE));
+                    return true;
+                }
+            }
+            return false;
         }
 
-        public bool PickSpot() {
+        /// <summary>
+        /// Checks a specific column on a win.
+        /// </summary>
+        /// <param name="y">Column index</param>
+        /// <returns>True if a win was found</returns>
+        private bool CheckColumn(in int y) {
+            var circlecount = 0;
+            var crosscount = 0;
+            for (var x = 0; x < GRIDSIZE; x++) {
+                switch (_field[y, x]) {
+                case Player.Circle:
+                    circlecount++;
+                    break;
+                case Player.Cross:
+                    crosscount++;
+                    break;
+                case Player.Empty:
+                    return false;
+                default:
+                    throw new InvalidProgramException("Unexpected enumerable state!");
+                }
+            }
+            if (crosscount == GRIDSIZE) {
+                Winner = Player.Cross;
+                return true;
+            }
+            if (circlecount == GRIDSIZE) {
+                Winner = Player.Circle;
+                return true;
+            }
+            return false;
+        }
+
+        /// <summary>
+        /// Checks all rows on a win.
+        /// </summary>
+        /// <returns>True if a win was found</returns>
+        private bool CheckRows() {
+            for (var y = 0; y < GRIDSIZE; y++) {
+                if (CheckRow(in y)) {
+                    WinningLine = ((0, y), (GRIDSIZE, y));
+                    return true;
+                }
+            }
+            return false;
+        }
+
+        /// <summary>
+        /// Checks a specific row on a win.
+        /// </summary>
+        /// <param name="y">Row index</param>
+        /// <returns>True if a win was found</returns>
+        private bool CheckRow(in int y) {
+            var circlecount = 0;
+            var crosscount = 0;
+            for (var x = 0; x < GRIDSIZE; x++) {
+                switch (_field[x, y]) {
+                case Player.Circle:
+                    circlecount++;
+                    break;
+                case Player.Cross:
+                    crosscount++;
+                    break;
+                case Player.Empty:
+                    return false;
+                default:
+                    throw new InvalidProgramException("Unexpected enumerable state!");
+                }
+            }
+            if (crosscount == GRIDSIZE) {
+                Winner = Player.Cross;
+                return true;
+            }
+            if (circlecount == GRIDSIZE) {
+                Winner = Player.Circle;
+                return true;
+            }
+            return false;
+        }
+        #endregion
+
+        /// <summary>
+        /// Writes the grid data into a string. All rows are printed pipe ('|') separated and all row items are printed comma (',') separated.
+        /// </summary>
+        /// <returns>A string uniquely identifying the grid</returns>
+        public override string ToString() {
+            var sb = new StringBuilder();
+            for (var y = 0; y < GRIDSIZE; y++) {
+                if (y > 0)
+                    sb.Append("|");
+                for (var x = 0; x < GRIDSIZE; x++) {
+                    if (x > 0)
+                        sb.Append(",");
+                    sb.Append(GetPlayerChar(_field[x, y]));
+                }
+            }
+            return sb.ToString();
+        }
+
+        public static char GetPlayerChar(Player player) {
+            switch (player) {
+            case Player.Empty:
+                return ' ';
+            case Player.Cross:
+                return 'X';
+            case Player.Circle:
+                return 'O';
+            default:
+                throw new Exception("Unexpected enumerable state!");
+            };
         }
     }
 }

TicTacToe/Player.cs

@@ -1,5 +1,5 @@
 namespace TicTacToe {
-    enum Player {
+    public enum Player {
         Empty = 0,
         Cross = 1,
         Circle = 2