Fix player movement and rotation

Signed-off-by: Hans Kokx <hans.d.kokx@gmail.com>

lib/main.dart

@@ -1,6 +1,7 @@
 import "dart:math" as math;
 
 import "package:flutter/material.dart";
+import "package:flutter/services.dart";
 
 // dart format off
 const List<int> map = [
@@ -65,6 +66,8 @@ class Player extends StatefulWidget {
 }
 
 class _PlayerState extends State<Player> {
+  late final FocusNode _focusNode;
+
   double playerAngle = 0;
   double get playerDeltaX => math.cos(playerAngle) * 5;
   double get playerDeltaY => math.sin(playerAngle) * 5;
@@ -73,10 +76,56 @@ class _PlayerState extends State<Player> {
 
   Offset playerPosition = const Offset(1.5 * mapSize, 1.5 * mapSize);
 
+  @override
+  void initState() {
+    super.initState();
+    _focusNode = FocusNode()..requestFocus();
+  }
+
+  @override
+  void dispose() {
+    _focusNode.dispose();
+    super.dispose();
+  }
+
   @override
   Widget build(BuildContext context) {
-    return CustomPaint(
-      painter: PlayerPainter(offset: playerPosition, delta: playerDelta),
+    return KeyboardListener(
+      focusNode: _focusNode,
+      onKeyEvent: (value) {
+        if (value is! KeyDownEvent && value is! KeyRepeatEvent) return;
+
+        final LogicalKeyboardKey key = value.logicalKey;
+
+        if (key == LogicalKeyboardKey.keyA) {
+          // Move left
+          playerAngle -= 0.1;
+          if (playerAngle < 0) {
+            playerAngle += 2 * math.pi;
+          }
+        } else if (key == LogicalKeyboardKey.keyD) {
+          // Move right
+          playerAngle += 0.1;
+
+          if (playerAngle > 2 * math.pi) {
+            playerAngle -= 2 * math.pi;
+          }
+        } else if (key == LogicalKeyboardKey.keyW) {
+          // Move forward
+          playerPosition += playerDelta;
+        } else if (key == LogicalKeyboardKey.keyS) {
+          // Move backwwards
+          playerPosition -= playerDelta;
+        }
+
+        setState(() {});
+      },
+      child: CustomPaint(
+        painter: PlayerPainter(
+          offset: playerPosition,
+          delta: playerDelta,
+        ),
+      ),
     );
   }
 }
@@ -101,7 +150,7 @@ class PlayerPainter extends CustomPainter {
     // Player direction line
     canvas.drawLine(
       offset + const Offset(4, 4),
-      delta * 5,
+      offset + const Offset(4, 4) + (delta * 5),
       Paint()
         ..color = Colors.yellow
         ..strokeWidth = 2,