Day 1 part 1 complete

lib/day1/command.dart

@@ -3,6 +3,37 @@ import "dart:io";
 
 import "package:args/command_runner.dart";
 
+enum Direction { left, right }
+
+class Rotation {
+  Direction direction;
+  int amount;
+  Rotation(this.direction, this.amount);
+
+  @override
+  String toString() {
+    return '{ direction: ${direction.name}, amount: $amount }';
+  }
+}
+
+Future<List<Rotation>> parseInputFile(String filePath) async {
+  var inputFile = File(filePath);
+  var openFile = inputFile.openRead();
+
+  var lines = openFile.transform(utf8.decoder).transform(LineSplitter());
+
+  List<Rotation> inputList = [];
+  await for (var line in lines) {
+    var dir = line.substring(0, 1);
+    var amount = int.parse(line.substring(1, line.length));
+    inputList.add(
+      Rotation(dir == 'L' ? Direction.left : Direction.right, amount),
+    );
+  }
+
+  return inputList;
+}
+
 class Day1Command extends Command {
   // The [name] and [description] properties must be defined by every
   // subclass.
@@ -19,10 +50,9 @@ class Day1Command extends Command {
 
   // [run] may also return a Future.
   @override
-  void run() {
+  Future<void> run() async {
     // [argResults] is set before [run()] is called and contains the flags/options
     // passed to this command.
-    print(argResults!.rest);
 
     if (argResults!.rest.length != 1) {
       print(
@@ -31,22 +61,29 @@ class Day1Command extends Command {
     }
     var fileName = argResults!.rest[0];
 
-    var inputFile = File(fileName);
-    var openFile = inputFile.openRead();
+    print("Parsing file: $fileName");
 
-    openFile
-        .transform(utf8.decoder)
-        .transform(LineSplitter())
-        .listen(
-          (String line) {
-            print('$line: ${line.length} bytes');
-          },
-          onDone: () {
-            print('File is now closed.');
-          },
-          onError: (e) {
-            print(e.toString());
-          },
-        );
+    var list = await parseInputFile(fileName);
+
+    int dialValue = 50;
+    int combination = 0;
+
+    for (var instruction in list) {
+      switch (instruction.direction) {
+        case Direction.left:
+          // Dial counter-clockwise by amount
+          dialValue -= instruction.amount;
+        case Direction.right:
+          // Dial clockwise by amount
+          dialValue += instruction.amount;
+      }
+
+      dialValue = dialValue % 100;
+      if (dialValue == 0) {
+        combination++;
+      }
+    }
+
+    print("Combination: $combination");
   }
 }