Day 24: The celebration night.

README.md

@@ -69,6 +69,7 @@ Here are the different challenges :
 - [Day 21: Refactor the tests and production code to Output-Based tests.](exercise/day21/docs/challenge.md)
 - [Day 22: Design a diamond program using T.D.D and Property-Based Testing.](exercise/day22/docs/challenge.md)
 - [Day 23: Refactor the code after putting it under test.](exercise/day23/docs/challenge.md)
+- [Day 24: Write the most complicated code you can.](exercise/day24/docs/challenge.md)
 
 ### Solutions
 A solution proposal will be published here every day during the `Advent Of Craft` containing `the code` and a `step by step` guide.

exercise/day24/docs/challenge.md

@@ -0,0 +1,23 @@
+## Day 24: The celebration night.
+
+Your last battle was a full victory, and you are ready to celebrate with
+your kingdom. A big celebration is being prepared.
+
+Today is about indulgence, excess and feast.
+
+On today's challenge, the last thing you want is to think about your craft and
+as such, the point of the exercise is to increase complexity of the code.
+
+Yes, you heard right.
+
+Using the [`Crappy-Driven Development`](https://github.com/ythirion/crappy-driven-development) technique, you have to make your
+code the crappiest possible.
+
+> "The secret art of making yourself indispensable by writing crappy code !!!"
+
+> **Challenge of day 24: Write the most complicated code you can.**
+
+- <u>💡HINT:</u> Your IDE can also help you write difficult code.
+
+![Crappy Driven Development](cdd.png)
+![Snippet](snippet.png)

exercise/day24/pom.xml

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+<?xml version="1.0" encoding="UTF-8"?>
+<project xmlns="http://maven.apache.org/POM/4.0.0"
+         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+    <modelVersion>4.0.0</modelVersion>
+
+    <parent>
+        <groupId>com.advent-of-craft</groupId>
+        <artifactId>advent-of-craft2023</artifactId>
+        <version>1.0-SNAPSHOT</version>
+    </parent>
+
+    <artifactId>dive</artifactId>
+    <version>1.0-SNAPSHOT</version>
+</project>

exercise/day24/src/main/java/M/Instruction.java

@@ -0,0 +1,8 @@
+package M;
+
+public record Instruction(String text, int x) {
+    public static Instruction fromText(String text) {
+        var split = text.split(" ");
+        return new Instruction(split[0], Integer.parseInt(split[1]));
+    }
+}

exercise/day24/src/main/java/M/Position.java

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+package M;
+
+public record Position(int horizontal, int depth) {
+    public Position changeDepth(int newDepth) {
+        return new Position(horizontal, newDepth);
+    }
+
+    public Position moveHorizontally(int newHorizontal) {
+        return new Position(newHorizontal, depth);
+    }
+}

exercise/day24/src/main/java/M/Submarine.java

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+package M;
+
+import java.util.List;
+
+public class Submarine {
+    private final Position position;
+
+    private Submarine(Position position) {
+        this.position = position;
+    }
+
+    public Submarine(int horizontal, int depth) {
+        this(new Position(horizontal, depth));
+    }
+
+    public Submarine move(List<Instruction> instructions) {
+        return instructions
+                .stream()
+                .reduce(this, Submarine::move, (p, n) -> p);
+    }
+
+    private Submarine move(Instruction instruction) {
+        return new Submarine(switch (instruction.text()) {
+            case "down" -> position.changeDepth(position.depth() + instruction.x());
+            case "up" -> position.changeDepth(position.depth() - instruction.x());
+            default -> position.moveHorizontally(position.horizontal() + instruction.x());
+        });
+    }
+
+    public Position getPosition() {
+        return position;
+    }
+}

exercise/day24/src/test/java/M/FileUtils.java

@@ -0,0 +1,19 @@
+package M;
+
+import java.io.IOException;
+import java.net.URISyntaxException;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.util.Objects;
+
+import static java.lang.System.lineSeparator;
+
+public class FileUtils {
+    public static String getInputAsString(String input) throws URISyntaxException, IOException {
+        return Files.readString(Path.of(Objects.requireNonNull(FileUtils.class.getClassLoader().getResource(input)).toURI()));
+    }
+
+    public static String[] getInputAsSeparatedLines(String input) throws URISyntaxException, IOException {
+        return getInputAsString(input).split(lineSeparator());
+    }
+}

exercise/day24/src/test/java/M/SubmarineTests.java

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+package M;
+
+import org.junit.jupiter.api.Test;
+
+import java.io.IOException;
+import java.net.URISyntaxException;
+import java.util.Arrays;
+import java.util.List;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+// Original specifications available here : https://adventofcode.com/2021/day/2
+class SubmarineTests {
+    @Test
+    void should_move_on_given_instructions() throws URISyntaxException, IOException {
+        var instructions = loadInstructions();
+        var submarine = new Submarine(0, 0)
+                .move(instructions);
+
+        assertThat(calculateResult(submarine))
+                .isEqualTo(1_690_020);
+    }
+
+    private int calculateResult(Submarine submarine) {
+        return submarine.getPosition().depth() * submarine.getPosition().horizontal();
+    }
+
+    private List<Instruction> loadInstructions() throws URISyntaxException, IOException {
+        return Arrays.stream(FileUtils.getInputAsSeparatedLines("submarine.txt"))
+                .map(Instruction::fromText)
+                .toList();
+    }
+}