Starting with password caching.

src/main/java/org/samo_lego/simpleauth/SimpleAuth.java

@@ -5,21 +5,21 @@ import net.fabricmc.fabric.api.event.player.*;
 import net.fabricmc.fabric.api.event.server.ServerStopCallback;
 import net.fabricmc.fabric.api.registry.CommandRegistry;
 import net.fabricmc.loader.api.FabricLoader;
-import net.minecraft.entity.player.PlayerEntity;
 import net.minecraft.server.network.ServerPlayerEntity;
 import net.minecraft.text.LiteralText;
 import net.minecraft.text.Text;
 import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
 import org.samo_lego.simpleauth.commands.*;
-import org.samo_lego.simpleauth.database.SimpleAuthDatabase;
 import org.samo_lego.simpleauth.event.AuthEventHandler;
 import org.samo_lego.simpleauth.event.entity.player.ChatCallback;
 import org.samo_lego.simpleauth.event.entity.player.PlayerJoinServerCallback;
 import org.samo_lego.simpleauth.event.entity.player.PlayerMoveCallback;
 import org.samo_lego.simpleauth.event.item.DropItemCallback;
 import org.samo_lego.simpleauth.event.item.TakeItemCallback;
-import org.samo_lego.simpleauth.utils.AuthConfig;
+import org.samo_lego.simpleauth.storage.AuthConfig;
+import org.samo_lego.simpleauth.storage.PlayerCache;
+import org.samo_lego.simpleauth.storage.SimpleAuthDatabase;
 
 import java.io.File;
 import java.util.HashMap;
@@ -33,11 +33,12 @@ public class SimpleAuth implements DedicatedServerModInitializer {
 
     // HashMap of players that are not authenticated
 	// Rather than storing all the authenticated players, we just store ones that are not authenticated
-	public static HashMap<PlayerEntity, Integer> deauthenticatedUsers = new HashMap<>();
+	// It stores some data as well, e.g. login tries and user password
+	public static HashMap<String, PlayerCache> deauthenticatedUsers = new HashMap<>();
 
 	// Boolean for easier checking if player is authenticated
 	public static boolean isAuthenticated(ServerPlayerEntity player) {
-		return !deauthenticatedUsers.containsKey(player);
+		return !deauthenticatedUsers.containsKey(player.getUuidAsString());
 	}
 
 	// Getting game directory
@@ -94,7 +95,7 @@ public class SimpleAuth implements DedicatedServerModInitializer {
 
 	// Authenticates player and sends the message
 	public static void authenticatePlayer(ServerPlayerEntity player, Text msg) {
-		deauthenticatedUsers.remove(player);
+		deauthenticatedUsers.remove(player.getUuidAsString());
 		// Player no longer needs to be invisible and invulnerable
 		player.setInvulnerable(false);
 		player.setInvisible(false);
@@ -112,7 +113,8 @@ public class SimpleAuth implements DedicatedServerModInitializer {
 	// De-authenticates player
 	public static void deauthenticatePlayer(ServerPlayerEntity player) {
 		// Marking player as not authenticated, (re)setting login tries to zero
-		SimpleAuth.deauthenticatedUsers.put(player, 0);
+		String uuid = player.getUuidAsString();
+		SimpleAuth.deauthenticatedUsers.put(uuid, new PlayerCache(uuid));
 
 		// Player is now not authenticated
 		player.sendMessage(notAuthenticated());

src/main/java/org/samo_lego/simpleauth/commands/AuthCommand.java

@@ -8,7 +8,7 @@ import net.minecraft.text.Text;
 import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
 import org.samo_lego.simpleauth.SimpleAuth;
-import org.samo_lego.simpleauth.utils.AuthConfig;
+import org.samo_lego.simpleauth.storage.AuthConfig;
 import org.samo_lego.simpleauth.utils.AuthHelper;
 
 import java.io.File;

src/main/java/org/samo_lego/simpleauth/commands/ChangepwCommand.java

@@ -67,7 +67,7 @@ public class ChangepwCommand {
                 ));
                 return 0;
             }
-            SimpleAuth.db.update(
+            SimpleAuth.db.updateUserData(
                     player.getUuidAsString(),
                     AuthHelper.hashPass(newPass.toCharArray())
             );

src/main/java/org/samo_lego/simpleauth/commands/LoginCommand.java

@@ -7,6 +7,7 @@ import net.minecraft.server.network.ServerPlayerEntity;
 import net.minecraft.text.LiteralText;
 import net.minecraft.text.Text;
 import org.samo_lego.simpleauth.SimpleAuth;
+import org.samo_lego.simpleauth.storage.PlayerCache;
 import org.samo_lego.simpleauth.utils.AuthHelper;
 
 import static com.mojang.brigadier.arguments.StringArgumentType.getString;
@@ -39,20 +40,21 @@ public class LoginCommand {
     private static int login(ServerCommandSource source, String pass) throws CommandSyntaxException {
         // Getting the player who send the command
         ServerPlayerEntity player = source.getPlayer();
+        String uuid = player.getUuidAsString();
 
         if(SimpleAuth.isAuthenticated(player)) {
             player.sendMessage(alreadyAuthenticated);
             return 0;
         }
-        else if(SimpleAuth.deauthenticatedUsers.get(player) >= maxLoginTries && maxLoginTries != -1) {
+        else if(SimpleAuth.deauthenticatedUsers.get(uuid).loginTries >= maxLoginTries && maxLoginTries != -1) {
             player.networkHandler.disconnect(loginTriesExceeded);
             return 0;
         }
-        else if (AuthHelper.checkPass(player.getUuidAsString(), pass.toCharArray()) == 1) {
+        else if (AuthHelper.checkPass(uuid, pass.toCharArray()) == 1) {
             SimpleAuth.authenticatePlayer(player, successfullyAuthenticated);
             return 1;
         }
-        else if(AuthHelper.checkPass(player.getUuidAsString(), pass.toCharArray()) == -1) {
+        else if(AuthHelper.checkPass(uuid, pass.toCharArray()) == -1) {
             player.sendMessage(notRegistered);
             return 0;
         }
@@ -64,10 +66,7 @@ public class LoginCommand {
         // Sending wrong pass message
         player.sendMessage(wrongPassword);
         // ++ the login tries
-        SimpleAuth.deauthenticatedUsers.replace(
+        SimpleAuth.deauthenticatedUsers.getOrDefault(uuid, new PlayerCache(uuid)).loginTries += 1;
-                player,
-                SimpleAuth.deauthenticatedUsers.getOrDefault(player, 0) + 1
-        );
         return 0;
     }
 }

src/main/java/org/samo_lego/simpleauth/commands/UnregisterCommand.java

@@ -47,7 +47,7 @@ public class UnregisterCommand {
         }
         else if (AuthHelper.checkPass(player.getUuidAsString(), pass.toCharArray()) == 1) {
             SimpleAuth.deauthenticatePlayer(player);
-            SimpleAuth.db.delete(player.getUuidAsString());
+            SimpleAuth.db.deleteUserData(player.getUuidAsString());
             player.sendMessage(accountDeleted);
             return 1;
         }

src/main/java/org/samo_lego/simpleauth/storage/AuthConfig.java

@@ -15,7 +15,7 @@
     You should have received a copy of the GNU General Public License
     along with this program.  If not, see <https://www.gnu.org/licenses/>.
 */
-package org.samo_lego.simpleauth.utils;
+package org.samo_lego.simpleauth.storage;
 
 import com.google.gson.Gson;
 import com.google.gson.GsonBuilder;

src/main/java/org/samo_lego/simpleauth/storage/PlayerCache.java

@@ -0,0 +1,25 @@
+package org.samo_lego.simpleauth.storage;
+
+import org.samo_lego.simpleauth.SimpleAuth;
+
+public class PlayerCache {
+    public boolean isRegistered;
+    public boolean isAuthenticated;
+    public String password;
+    public int loginTries;
+
+    public PlayerCache(String uuid) {
+        SimpleAuthDatabase db = SimpleAuth.db;
+
+        this.isAuthenticated = false;
+        this.loginTries = 0;
+        if(db.isUserRegistered(uuid)) {
+            this.isRegistered = true;
+            this.password = db.getPassword(uuid);
+        }
+        else {
+            this.isRegistered = false;
+            this.password = "";
+        }
+    }
+}

src/main/java/org/samo_lego/simpleauth/storage/SimpleAuthDatabase.java

@@ -1,4 +1,4 @@
-package org.samo_lego.simpleauth.database;
+package org.samo_lego.simpleauth.storage;
 
 import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
@@ -54,7 +54,7 @@ public class SimpleAuthDatabase {
     }
 
     // Checks if user is registered
-    private boolean isUserRegistered(String uuid) {
+    public boolean isUserRegistered(String uuid) {
         try {
             return levelDBStore.get(bytes("UUID:" + uuid)) != null;
         } catch (DBException e) {

src/main/java/org/samo_lego/simpleauth/utils/AuthHelper.java

@@ -10,7 +10,7 @@ public class AuthHelper {
     private static final Logger LOGGER = LogManager.getLogger();
 
     // Creating the instance
-    private static Argon2 argon2 = Argon2Factory.create();
+    private static final Argon2 argon2 = Argon2Factory.create();
 
     // Returns 1 if password is correct, 0 if not
     // and -1 if user is not registered yet
@@ -30,8 +30,13 @@ public class AuthHelper {
         }
         else {
             try {
+                String hashed;
+                // Password from cache
+                if(SimpleAuth.deauthenticatedUsers.containsKey(uuid))
+                    hashed = SimpleAuth.deauthenticatedUsers.get(uuid).password;
                 // Hashed password from DB
-                String hashed = SimpleAuth.db.getPassword(uuid);
+                else
+                    hashed = SimpleAuth.db.getPassword(uuid);
                 if(hashed.equals(""))
                     return -1;  // User is not yet registered
                 // Verify password