From e10776dc0bb6b4edcaca60fefc09b639942628a6 Mon Sep 17 00:00:00 2001
From: overflowerror <mail@overflowerror.com>
Date: Sat, 30 Dec 2023 14:34:54 +0100
Subject: [PATCH] feat: Add kings to game system

---
 src/Game/King.php       | 35 ++++++++++++++++
 tests/Game/KingTest.php | 93 +++++++++++++++++++++++++++++++++++++++++
 2 files changed, 128 insertions(+)
 create mode 100644 src/Game/King.php
 create mode 100644 tests/Game/KingTest.php

diff --git a/src/Game/King.php b/src/Game/King.php
new file mode 100644
index 0000000..4a6f342
--- /dev/null
+++ b/src/Game/King.php
@@ -0,0 +1,35 @@
+<?php
+
+namespace Game;
+
+class King extends Piece {
+
+    public function getName(): string {
+        return "King";
+    }
+
+    public function getShort(): string {
+        return "K";
+    }
+
+    public function getMoveCandidateMap(FieldBitMap $occupied, FieldBitMap $captureable, FieldBitMap $threatened): FieldBitMap {
+        $result = FieldBitMap::empty();
+
+        $checkCandidate = function(Position $position) use (&$result, $occupied, $captureable, $threatened) {
+            if ($position->isValid() && !$occupied->has($position) && !$threatened->has($position)) {
+                $result->add($position);
+            }
+        };
+
+        $checkCandidate(new Position($this->position->file - 1, $this->position->rank - 1));
+        $checkCandidate(new Position($this->position->file - 1, $this->position->rank + 0));
+        $checkCandidate(new Position($this->position->file - 1, $this->position->rank + 1));
+        $checkCandidate(new Position($this->position->file + 0, $this->position->rank - 1));
+        $checkCandidate(new Position($this->position->file + 0, $this->position->rank + 1));
+        $checkCandidate(new Position($this->position->file + 1, $this->position->rank - 1));
+        $checkCandidate(new Position($this->position->file + 1, $this->position->rank + 0));
+        $checkCandidate(new Position($this->position->file + 1, $this->position->rank + 1));
+
+        return $result;
+    }
+}
\ No newline at end of file
diff --git a/tests/Game/KingTest.php b/tests/Game/KingTest.php
new file mode 100644
index 0000000..953bc36
--- /dev/null
+++ b/tests/Game/KingTest.php
@@ -0,0 +1,93 @@
+<?php
+declare(strict_types=1);
+
+namespace Game;
+
+use PHPUnit\Framework\TestCase;
+
+final class KingTest extends TestCase {
+
+    public function testMoves_unobstructed() {
+        $subject = new King(new Position(
+            3, 4
+        ), Side::WHITE);
+
+        $result = $subject->getMoveCandidateMap(FieldBitMap::empty(), FieldBitMap::empty(), FieldBitMap::empty());
+
+        $this->assertTrue(
+            $result->equals(new FieldBitMap([
+                new Position(2, 3),
+                new Position(2, 4),
+                new Position(2, 5),
+                new Position(3, 3),
+                new Position(3, 5),
+                new Position(4, 3),
+                new Position(4, 4),
+                new Position(4, 5),
+            ]))
+        );
+    }
+
+    public function testMoves_obstructed() {
+        $subject = new King(new Position(
+            3, 0
+        ), Side::WHITE);
+
+        $result = $subject->getMoveCandidateMap(
+            new FieldBitMap([
+                new Position(3, 1),
+            ]),
+            new FieldBitMap([
+                new Position(2, 1),
+            ]),
+            new FieldBitMap([
+               new Position(2, 0),
+            ]),
+        );
+
+        $this->assertTrue(
+            $result->equals(new FieldBitMap([
+                new Position(2, 1),
+                new Position(4, 1),
+                new Position(4, 0),
+            ]))
+        );
+    }
+
+    public function testCaptureable() {
+        $subject = new King(
+            new Position(5, 6),
+            Side::WHITE,
+        );
+
+        $this->assertTrue(
+            $subject->getCaptureableMap(true)->equals(new FieldBitMap([
+                new Position(5, 6)
+            ]))
+        );
+    }
+
+    public function testCaptureMap() {
+        $subject = new King(new Position(
+            5, 2
+        ), Side::WHITE);
+
+        $result = $subject->getCaptureMap(
+            new FieldBitMap([
+                new Position(4, 3),
+                new Position(4, 1),
+                new Position(6, 3),
+                new Position(6, 1),
+            ])
+        );
+
+        $this->assertTrue(
+            $result->equals(new FieldBitMap([
+                new Position(5, 1),
+                new Position(5, 3),
+                new Position(4, 2),
+                new Position(6, 2),
+            ]))
+        );
+    }
+}
\ No newline at end of file