From c4d707d64a208d177a8b6b32b8cd2b77f8a7249f Mon Sep 17 00:00:00 2001
From: Manuel Friedli <manuel@fritteli.ch>
Date: Sat, 14 Dec 2024 04:50:30 +0100
Subject: [PATCH] Very simple way to specify the algorithm to use to generate
 mazes.

---
 docker/Dockerfile                             |  7 ++-
 pom.xml                                       |  2 +-
 .../ch/fritteli/maze/server/Algorithm.java    | 45 +++++++++++++++++++
 .../handler/ParametersToMazeExtractor.java    |  7 ++-
 .../maze/server/handler/RequestParameter.java |  5 ++-
 5 files changed, 62 insertions(+), 4 deletions(-)
 create mode 100644 src/main/java/ch/fritteli/maze/server/Algorithm.java

diff --git a/docker/Dockerfile b/docker/Dockerfile
index 9680592..74a2661 100644
--- a/docker/Dockerfile
+++ b/docker/Dockerfile
@@ -4,4 +4,9 @@ COPY target/maze-server-*.jar /app/
 RUN rm /app/*-sources.jar
 RUN mv /app/*.jar /app/app.jar
 
-CMD java -Dfritteli.maze.server.host=0.0.0.0 -Dfritteli.maze.server.port=80 -jar /app/app.jar
+CMD java \
+    -Dfritteli.maze.server.host=0.0.0.0 \
+    -Dfritteli.maze.server.port=80 \
+    -Dfritteli.maze.maxheight=256 \
+    -Dfritteli.maze.maxwidth=256 \
+    -jar /app/app.jar
diff --git a/pom.xml b/pom.xml
index aed0ac3..6693fcf 100644
--- a/pom.xml
+++ b/pom.xml
@@ -56,7 +56,7 @@
     </distributionManagement>
 
     <properties>
-        <maze-generator.version>0.2.1</maze-generator.version>
+        <maze-generator.version>0.2.2-SNAPSHOT</maze-generator.version>
         <maven-site-plugin.version>4.0.0-M8</maven-site-plugin.version>
         <undertow.version>2.3.18.Final</undertow.version>
     </properties>
diff --git a/src/main/java/ch/fritteli/maze/server/Algorithm.java b/src/main/java/ch/fritteli/maze/server/Algorithm.java
new file mode 100644
index 0000000..3b0dcf7
--- /dev/null
+++ b/src/main/java/ch/fritteli/maze/server/Algorithm.java
@@ -0,0 +1,45 @@
+package ch.fritteli.maze.server;
+
+import ch.fritteli.maze.generator.algorithm.MazeGeneratorAlgorithm;
+import ch.fritteli.maze.generator.algorithm.RandomDepthFirst;
+import ch.fritteli.maze.generator.algorithm.Wilson;
+import ch.fritteli.maze.generator.model.Maze;
+import io.vavr.collection.List;
+import io.vavr.collection.Stream;
+import io.vavr.control.Option;
+import lombok.Getter;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+
+import java.util.function.Function;
+
+public enum Algorithm {
+    RANDOM_DEPTH_FIRST(RandomDepthFirst::new, "random", "random-depth-first"),
+    WILSON(Wilson::new, "wilson");
+
+    @NotNull
+    private final Function<Maze, MazeGeneratorAlgorithm> creator;
+
+    @Getter
+    @NotNull
+    private final List<String> names;
+
+    Algorithm(@NotNull final Function<Maze, MazeGeneratorAlgorithm> creator,
+              @NotNull final String... names) {
+        this.creator = creator;
+        this.names = List.of(names);
+    }
+
+    @NotNull
+    public static Option<Algorithm> ofString(@Nullable final String name) {
+        return Option.of(name)
+                .map(String::toLowerCase)
+                .flatMap(nameLC -> Stream.of(values())
+                        .find(algorithm -> algorithm.getNames().contains(nameLC)));
+    }
+
+    @NotNull
+    public MazeGeneratorAlgorithm createAlgorithm(@NotNull final Maze maze) {
+        return this.creator.apply(maze);
+    }
+}
diff --git a/src/main/java/ch/fritteli/maze/server/handler/ParametersToMazeExtractor.java b/src/main/java/ch/fritteli/maze/server/handler/ParametersToMazeExtractor.java
index 6c747e5..8ff14aa 100644
--- a/src/main/java/ch/fritteli/maze/server/handler/ParametersToMazeExtractor.java
+++ b/src/main/java/ch/fritteli/maze/server/handler/ParametersToMazeExtractor.java
@@ -3,6 +3,7 @@ package ch.fritteli.maze.server.handler;
 import ch.fritteli.maze.generator.algorithm.RandomDepthFirst;
 import ch.fritteli.maze.generator.model.Maze;
 import ch.fritteli.maze.generator.model.Position;
+import ch.fritteli.maze.server.Algorithm;
 import ch.fritteli.maze.server.InvalidRequestParameterException;
 import ch.fritteli.maze.server.OutputType;
 import io.vavr.collection.Stream;
@@ -33,6 +34,7 @@ class ParametersToMazeExtractor {
         final Option<Long> id = getParameterValue(RequestParameter.ID);
         final Option<Position> start = getParameterValue(RequestParameter.START);
         final Option<Position> end = getParameterValue(RequestParameter.END);
+        final Option<Algorithm> algorithm = getParameterValue(RequestParameter.ALGORITHM);
 
         if (output.isEmpty()) {
             return Try.failure(new InvalidRequestParameterException("Path parameter %s is required and must be one of: %s".formatted(
@@ -77,7 +79,10 @@ class ParametersToMazeExtractor {
             } else {
                 maze = new Maze(desiredWidth, desiredHeight, id.getOrElse(() -> new Random().nextLong()));
             }
-            new RandomDepthFirst(maze).run();
+
+            algorithm.getOrElse(Algorithm.RANDOM_DEPTH_FIRST)
+                    .createAlgorithm(maze)
+                    .run();
             return new GeneratedMaze(maze, output.get(), RandomDepthFirst.class.getSimpleName());
         });
     }
diff --git a/src/main/java/ch/fritteli/maze/server/handler/RequestParameter.java b/src/main/java/ch/fritteli/maze/server/handler/RequestParameter.java
index 3808313..5cdd893 100644
--- a/src/main/java/ch/fritteli/maze/server/handler/RequestParameter.java
+++ b/src/main/java/ch/fritteli/maze/server/handler/RequestParameter.java
@@ -1,6 +1,7 @@
 package ch.fritteli.maze.server.handler;
 
 import ch.fritteli.maze.generator.model.Position;
+import ch.fritteli.maze.server.Algorithm;
 import ch.fritteli.maze.server.OutputType;
 import io.vavr.Tuple2;
 import io.vavr.collection.HashMap;
@@ -44,7 +45,9 @@ enum RequestParameter {
                 return new Position(x, y);
             })
             .toOption()
-            .onEmpty(() -> log.debug("Unparseable value for parameter 'end': '{}'", p)), "e", "end");
+            .onEmpty(() -> log.debug("Unparseable value for parameter 'end': '{}'", p)), "e", "end"),
+    ALGORITHM(p -> Algorithm.ofString(p)
+            .onEmpty(() -> log.debug("Unparseable value for parameter 'algorithm': '{}'", p)), "a", "algorithm");
     @NotNull
     private final Function<String, Option<?>> extractor;
     @Getter