finish mvp

src/main/java/nouritsu/Dao.java

@@ -1,7 +1,9 @@
 package nouritsu;
 
 import io.vavr.collection.HashSet;
+import io.vavr.collection.List;
 import io.vavr.control.Either;
+import io.vavr.control.Option;
 import nouritsu.types.Resp;
 import nouritsu.types.Section;
 import nouritsu.types.ShoppingItem;
@@ -13,6 +15,11 @@ import java.util.function.Function;
 
 public class Dao {
   private final JedisPool pool;
+  // Prefixes for the redis keys because other applications might also be using the redis
+  private static final String PREFIX = "nouritsu_";
+  private static final String USER_PREFIX = PREFIX + "user_";
+  private static final String STORE_PREFIX = PREFIX + "store_";
+  private static final String ITEM_PREFIX = PREFIX + "item_";
 
   Dao() {
     pool = new JedisPool();
@@ -24,31 +31,72 @@ public class Dao {
     }
   }
 
+  private Option<ShoppingItem> getItem(String name) {
+    return Option.of(withRedis(redis -> redis.get(ITEM_PREFIX + name)))
+      .flatMap(section -> Section.tryParse(section).toOption())
+      .map(section -> new ShoppingItem(name, section));
+  }
+
   public String clearList(String id) {
-    withRedis(redis -> redis.del(id));
+    withRedis(redis -> redis.del(USER_PREFIX + id));
     // Just always return okay, even if we didn’t have data to begin with.
     // Idempotency yay \o/
     return "Cleared list of user “%s“".formatted(id);
   }
 
-  public Either<Resp, HashSet<ShoppingItem>> getList(String id) {
+  private Option<HashSet<String>> getSet(String key) {
     return withRedis(redis ->
-      redis.exists(id)
-        ? Either.right(HashSet.ofAll(redis.smembers(id)).map(s -> new ShoppingItem(s, Section.CANS)))
-        : Either.left(Resp.NOT_FOUND.apply("No list found for user “%s”".formatted(id)))
+      redis.exists(key)
+        ? Option.some(HashSet.ofAll(redis.smembers(key)))
+        : Option.none()
     );
   }
 
+  public Either<Resp, HashSet<ShoppingItem>> getList(String id) {
+    return getSet(USER_PREFIX + id)
+      .map(items -> items.map(this::getItem).map(Option::get))
+      .toEither(Resp.NOT_FOUND.apply("No list found for user “%s”".formatted(id)));
+  }
+
+  public Either<Resp, Store> getStore(String name) {
+    return withRedis(redis -> Option.of(redis.lrange(STORE_PREFIX + name, 0, 1000L))
+      .toEither(Resp.BAD_REQUEST.apply("Store %s not found".formatted(name)))
+      .map(sections -> sections.stream()
+        .map(Section::tryParse)
+        // Safe; elements in persistence must have a valid section
+        .map(Either::get)
+        .collect(List.collector()))
+      .map(sections -> new Store(name, sections))
+    );
+  }
+
+  // Check if an item is known and add it to the list if it is.
   public Either<Resp, String> addToList(String id, String item) {
-    return Either.right("Added “%s“ to list of user “%s”".formatted(item, id));
+    return getItem(item).map(it -> {
+      withRedis(redis -> redis.sadd(USER_PREFIX + id, item));
+      return "Added “%s“ to list of user “%s”".formatted(it, id);
+    }).toEither(Resp.BAD_REQUEST.apply("Item %s not found".formatted(item)));
   }
 
   public String addItem(ShoppingItem item) {
+    withRedis(redis -> redis.set(ITEM_PREFIX + item.name(), item.section().name()));
     return "Registered new item “%s” under the section “%s”"
       .formatted(item.name(), item.section().name().toLowerCase());
   }
 
-  public Either<Resp, String> addStore(Store store) {
-    return Either.right("Registered new store “%s” with the sections [%s]".formatted(store.name(), store.sections()));
+  public String addStore(Store store) {
+    // just overwrite it if we already know that store
+    withRedis(redis -> {
+        redis.del(STORE_PREFIX + store.name());
+        redis.rpush(
+          STORE_PREFIX + store.name(),
+          store.sections().map(Section::name).toJavaArray(String[]::new)
+        );
+        // There needs to be some kind of return type unless I make a second util function with Consumer<Jedis>.
+        // Why doesn’t Java just have a `Unit` type?
+        return true;
+      }
+    );
+    return "Registered new store “%s” with the sections [%s]".formatted(store.name(), store.sections());
   }
 }

src/main/java/nouritsu/Nouritsu.java

@@ -5,6 +5,7 @@ import fi.iki.elonen.NanoHTTPD.Response.Status;
 import io.vavr.Tuple;
 import io.vavr.Tuple2;
 import io.vavr.collection.HashMap;
+import io.vavr.collection.HashSet;
 import io.vavr.collection.Map;
 import io.vavr.control.Either;
 import io.vavr.control.Try;
@@ -30,7 +31,10 @@ public class Nouritsu extends NanoHTTPD {
     return Try.of(() -> processRequest(session, dao))
       .fold(
         // This won’t be exposed to the outside world, so returning the error message is fine
-        err -> newFixedLengthResponse(Status.INTERNAL_ERROR, MIME_PLAINTEXT, err.getMessage()),
+        err -> {
+          err.printStackTrace();
+          return newFixedLengthResponse(Status.INTERNAL_ERROR, MIME_PLAINTEXT, err.getMessage());
+        },
         response -> newFixedLengthResponse(response.status(), MIME_PLAINTEXT, response.text())
       );
   }
@@ -38,9 +42,10 @@ public class Nouritsu extends NanoHTTPD {
   private static final String HELP = """
     Valid endpoints are (not case sensitive):
     /addStore/?name=storeName&sections=first,second,third
-    /addItem/?name=itemName&category=itemCategory
+    /addItem/?name=itemName&section=itemSection
     /addToList/?user=userId&item=itemName
-    /getList/?user=userId&store=optionalStoreName
+    /getList/?user=userId
+    /getListForStore/?user=userId&store=StoreName
     /clearList/?user=userId
     """;
 
@@ -52,6 +57,7 @@ public class Nouritsu extends NanoHTTPD {
         case "additem" -> Nouritsu::addItem;
         case "addtolist" -> Nouritsu::addToList;
         case "getlist" -> Nouritsu::getList;
+        case "getlistforstore" -> Nouritsu::getListOrdered;
         case "clearlist" -> Nouritsu::clearList;
         default -> (_1, _2) -> Resp.NOT_FOUND.apply(HELP);
       };
@@ -83,6 +89,31 @@ public class Nouritsu extends NanoHTTPD {
       .fold(Function.identity(), Resp.OK);
   }
 
+  private static Resp getListOrdered(Map<String, String> params, Dao dao) {
+    return getAsTuple(params, "user", "store")
+      .flatMap(t -> t.apply((userId, storeName) ->
+        zip(dao.getList(userId), dao.getStore(storeName))
+      ))
+      .map(t -> t.apply(Nouritsu::sortBySection))
+      .fold(Function.identity(), Resp.OK);
+  }
+
+  private static String sortBySection(HashSet<ShoppingItem> items, Store store) {
+    var itemsBySection = items.groupBy(ShoppingItem::section);
+    var sorted = store.sections().flatMap(s -> itemsBySection.get(s).getOrElse(HashSet.empty()));
+    var rest = items.removeAll(sorted);
+    var sortedString = sorted.map(ShoppingItem::name).mkString(", ");
+    if (rest.isEmpty()) {
+      return sortedString;
+    }
+    return sortedString + rest.mkString("\nItems not available or not classified in this store: ", ", ", "");
+  }
+
+  // Return a Tuple2 containing the values of two eithers if both were Either.Right
+  private static <L, R1, R2> Either<L, Tuple2<R1, R2>> zip(Either<L, R1> first, Either<L, R2> second) {
+    return first.flatMap(f -> second.map(s -> Tuple.of(f, s)));
+  }
+
   private static Resp addToList(Map<String, String> params, Dao dao) {
     return getAsTuple(params, "user", "item")
       // This is where Kotlin-like destructuring would be really nice to have:
@@ -92,16 +123,16 @@ public class Nouritsu extends NanoHTTPD {
   }
 
   private static Resp addItem(Map<String, String> params, Dao dao) {
-    return getAsTuple(params, "name", "category")
+    return getAsTuple(params, "name", "section")
       .flatMap(t -> t.apply(ShoppingItem::tryParse))
       .map(dao::addItem)
       .fold(Function.identity(), Resp.CREATED);
   }
 
   private static Resp addStore(Map<String, String> params, Dao dao) {
-    return getAsTuple(params, "name", "categories")
+    return getAsTuple(params, "name", "sections")
       .flatMap(t -> t.apply(Store::tryParse))
-      .flatMap(dao::addStore)
+      .map(dao::addStore)
       .fold(Function.identity(), Resp.CREATED);
   }
 

src/main/java/nouritsu/types/Section.java

@@ -11,6 +11,7 @@ public enum Section {
   RICE,
   MEAT,
   FISH,
+  FROZEN,
   DAIRY,
   HYGIENE,
   BEVERAGES;