#8: Implement Login Logic

Signed-off-by: Dominik Säume <Dominik.Saeume@hmmh.de>

src/main/java/de/hitec/nhplus/Main.java

@@ -1,6 +1,7 @@
 package de.hitec.nhplus;
 
 import de.hitec.nhplus.datastorage.ConnectionBuilder;
+import de.hitec.nhplus.login.LoginController;
 import javafx.application.Application;
 import javafx.application.Platform;
 import javafx.fxml.FXMLLoader;
@@ -34,8 +35,8 @@ public class Main extends Application {
     @Override
     public void start(Stage primaryStage) {
         this.primaryStage = primaryStage;
-        //executePassword();
-        executeMainApplication();
+        executePassword();
+        //executeMainApplication();
     }
 
     private void executePassword() {
@@ -44,10 +45,19 @@ public class Main extends Application {
             FXMLLoader loader = new FXMLLoader(Main.class.getResource("/de/hitec/nhplus/login/LoginView.fxml"));
             BorderPane pane = loader.load();
             Scene scene = new Scene(pane);
-            this.primaryStage.setTitle("NHPlus");
-            this.primaryStage.setScene(scene);
-            this.primaryStage.setResizable(true);
-            this.primaryStage.show();
+            Stage loginStage = new Stage();
+            loginStage.setTitle("NHPlus");
+            loginStage.setScene(scene);
+            loginStage.setResizable(false);
+
+            LoginController controller = loader.getController();
+            controller.initialize(loginStage);
+
+            loginStage.showAndWait();
+
+            if(controller.loginSucessfull){
+                executeMainApplication();
+            }
         } catch (IOException exception) {
             exception.printStackTrace();
         }

src/main/java/de/hitec/nhplus/login/LoginController.java

@@ -1,8 +1,63 @@
 package de.hitec.nhplus.login;
 
+import de.hitec.nhplus.datastorage.DaoFactory;
+import de.hitec.nhplus.login.database.UserDao;
+import javafx.event.ActionEvent;
+import javafx.fxml.FXML;
+import javafx.scene.control.PasswordField;
+import javafx.scene.control.TextField;
+import javafx.stage.Stage;
+
+import java.nio.charset.StandardCharsets;
+import java.security.MessageDigest;
+import java.security.NoSuchAlgorithmException;
+import java.sql.SQLException;
+import java.util.Arrays;
+
 public class LoginController {
 
-    public void initialize() {
+    @FXML
+    public TextField textFieldUsername;
+    @FXML
+    public PasswordField passwordField;
+    private Stage stage;
+    public boolean loginSucessfull = false;
+    private int loginTries = 0;
+
+    public void initialize(Stage stage) {
+        this.stage = stage;
+    }
+
+    private void handleWrongPasswordOrUsername(){
+        loginTries++;
+        if(loginTries == 3){
+            stage.close();
+        }
+    }
+
+    @FXML
+    public void handleSubmit() {
+        UserDao dao = DaoFactory.getInstance().createUserDAO();
+        try {
+            int id = dao.readUserId(textFieldUsername.getText());
+            if (id == 0) {
+                handleWrongPasswordOrUsername();
+                return;
+            }
+            byte[] salt = dao.readPasswordSalt(id);
+            MessageDigest md = MessageDigest.getInstance("SHA-512");
+            md.update(salt);
+            byte[] hash = md.digest(passwordField.getText().getBytes(StandardCharsets.UTF_8));
+            byte[] requiredHash = dao.readPasswordHash(id);
+            if (!Arrays.equals(hash, requiredHash)) {
+                handleWrongPasswordOrUsername();
+                return;
+            }
+            loginSucessfull = true;
+            stage.close();
+        } catch (SQLException | NoSuchAlgorithmException exception) {
+            exception.printStackTrace();
+        }
 
     }
 }

src/main/resources/de/hitec/nhplus/login/LoginView.fxml

@@ -1,9 +1,11 @@
 <?xml version="1.0" encoding="UTF-8"?>
 
-<?import javafx.geometry.*?>
-<?import javafx.scene.control.*?>
+<?import javafx.geometry.Insets?>
+<?import javafx.scene.control.Button?>
+<?import javafx.scene.control.Label?>
+<?import javafx.scene.control.PasswordField?>
+<?import javafx.scene.control.TextField?>
 <?import javafx.scene.layout.*?>
-
 <BorderPane
         xmlns="http://javafx.com/javafx/17.0.2-ea"
         xmlns:fx="http://javafx.com/fxml/1"
@@ -15,18 +17,30 @@
         <Insets bottom="8" left="8" right="8" top="8"/>
     </padding>
     <top>
-        <Label text="Anmeldung" BorderPane.alignment="CENTER" />
+        <Label text="Anmeldung" BorderPane.alignment="CENTER"/>
     </top>
     <center>
         <VBox spacing="8">
             <BorderPane.margin>
                 <Insets bottom="8.0" top="8.0"/>
             </BorderPane.margin>
-            <TextField promptText="nutzername" VBox.vgrow="ALWAYS"/>
-            <PasswordField promptText="password" VBox.vgrow="ALWAYS"/>
+            <TextField
+                    fx:id="textFieldUsername"
+                    promptText="nutzername"
+                    VBox.vgrow="ALWAYS"
+            />
+            <PasswordField
+                    fx:id="passwordField"
+                    promptText="password"
+                    VBox.vgrow="ALWAYS"
+            />
         </VBox>
     </center>
     <bottom>
-        <Button text="Bestätigen" BorderPane.alignment="CENTER" />
+        <Button
+                text="Bestätigen"
+                BorderPane.alignment="CENTER"
+                onAction="#handleSubmit"
+        />
     </bottom>
 </BorderPane>