diff --git a/README.md b/README.md
index d20aaf9..7071577 100644
--- a/README.md
+++ b/README.md
@@ -1,3 +1,4 @@
+[![Review Assignment Due Date](https://classroom.github.com/assets/deadline-readme-button-22041afd0340ce965d47ae6ef1cefeee28c7c493a6346c4f15d667ab976d596c.svg)](https://classroom.github.com/a/339Lr3BJ)
 ### How the tests work (and Docker requirement)
 
 This project ships with an end‑to‑end CLI integration test suite that uses Testcontainers to spin up a temporary MySQL database. 
diff --git a/src/main/java/com/example/AccountRepository.java b/src/main/java/com/example/AccountRepository.java
new file mode 100644
index 0000000..5da19a5
--- /dev/null
+++ b/src/main/java/com/example/AccountRepository.java
@@ -0,0 +1,12 @@
+package com.example;
+
+public interface AccountRepository {
+
+    boolean isValidLogin(String username, String password);
+
+    boolean createAccount(String firstName, String lastName, String ssn, String password);
+
+    boolean updatePassword(long userId, String newPassword);
+
+    boolean deleteAccount(long userId);
+}
diff --git a/src/main/java/com/example/DataSource.java b/src/main/java/com/example/DataSource.java
new file mode 100644
index 0000000..b96b0c9
--- /dev/null
+++ b/src/main/java/com/example/DataSource.java
@@ -0,0 +1,11 @@
+package com.example;
+
+import java.sql.Connection;
+import java.sql.SQLException;
+
+// define a new standard method for connection
+public interface DataSource {
+
+    Connection getConnection() throws SQLException;
+
+}
\ No newline at end of file
diff --git a/src/main/java/com/example/JdbcAccountRepository.java b/src/main/java/com/example/JdbcAccountRepository.java
new file mode 100644
index 0000000..0b4963b
--- /dev/null
+++ b/src/main/java/com/example/JdbcAccountRepository.java
@@ -0,0 +1,107 @@
+package com.example;
+
+import java.sql.*;
+
+public class JdbcAccountRepository implements AccountRepository{
+
+    //Fetching Datasource object
+    private final DataSource dataSource;
+
+
+    //injection the datasource object into the constructor:
+    public JdbcAccountRepository(DataSource dataSource){
+        this.dataSource=dataSource;
+    }
+
+
+    @Override
+    public boolean isValidLogin(String username, String password) {
+        String sql = "SELECT COUNT(*) FROM account WHERE name = ? AND password = ?";
+
+        try(
+                Connection connection= dataSource.getConnection();
+                PreparedStatement ps= connection.prepareStatement(sql)
+                ) {
+                ps.setString(1, username);
+                ps.setString(2, password);
+
+                try(ResultSet rs = ps.executeQuery()) {
+                    if (rs.next()){
+                        return rs.getInt(1)>0;
+                    }
+                }
+
+        } catch (SQLException e){
+            System.err.println("Database error during login validation: " + e.getMessage());
+            return false;
+        }
+
+        return false;
+
+    }
+
+    @Override
+    public boolean createAccount(String firstName, String lastName, String ssn, String password) {
+
+        // concatenation of firstname and lastname to create username (name column in sql) for proper usage of the app.
+        String username = firstName.substring(0, Math.min(firstName.length(), 3)) +
+                lastName.substring(0, Math.min(lastName.length(), 3));
+
+        String sql= "INSERT INTO account (first_name, last_name, ssn, password, name) VALUES (?, ?, ?, ?, ?)";
+
+        try(Connection connection= dataSource.getConnection();
+            PreparedStatement ps= connection.prepareStatement(sql)){
+
+            ps.setString(1, firstName);
+            ps.setString(2, lastName);
+            ps.setString(3, ssn);
+            ps.setString(4, password);
+            ps.setString(5, username);
+
+            int rowsAffected= ps.executeUpdate();
+            return rowsAffected>0;
+        } catch (SQLException e){
+            System.err.println("Could not create account: " + e.getMessage());
+            return false;
+        }
+    }
+
+    @Override
+    public boolean updatePassword(long userId, String newPassword) {
+        String sql= "UPDATE account SET password = ? WHERE user_id = ?";
+
+        try(Connection connection= dataSource.getConnection();
+            PreparedStatement ps=connection.prepareStatement(sql)){
+
+            ps.setString(1, newPassword);
+            ps.setLong(2, userId);
+
+            int rowsAffected=ps.executeUpdate();
+            return rowsAffected>0;
+
+        }catch (SQLException e){
+            System.err.println(" Could not update password: " + e.getMessage());
+            return false;
+        }
+    }
+
+    @Override
+    public boolean deleteAccount(long userId) {
+        String sql= " DELETE FROM account WHERE user_id = ?";
+
+        try(Connection connection= dataSource.getConnection();
+            PreparedStatement ps=connection.prepareStatement(sql)){
+
+            ps.setLong(1, userId);
+
+            int rowsAffected=ps.executeUpdate();
+            return rowsAffected>0;
+
+        }catch (SQLException e){
+            System.err.println(" Could not delete account: " + e.getMessage());
+            return false;
+        }
+
+
+    }
+}
diff --git a/src/main/java/com/example/JdbcMoonMissionRepository.java b/src/main/java/com/example/JdbcMoonMissionRepository.java
new file mode 100644
index 0000000..fd91279
--- /dev/null
+++ b/src/main/java/com/example/JdbcMoonMissionRepository.java
@@ -0,0 +1,94 @@
+package com.example;
+
+import java.sql.*;
+import java.time.LocalDate;
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Optional;
+
+public class JdbcMoonMissionRepository implements MoonMissionRepository{
+
+    //declare datasource object
+    private final DataSource dataSource;
+
+
+// inject into contructor:
+    public JdbcMoonMissionRepository(DataSource dataSource){
+        this.dataSource=dataSource;
+    }
+
+    @Override
+    public List<String> findAllSpacecraftNames() {
+        List<String> names = new ArrayList<>();
+
+        String sql= "SELECT spacecraft FROM moon_mission ORDER BY launch_date";
+
+        try( Connection connection= dataSource.getConnection();
+        Statement statement= connection.createStatement();
+        ResultSet rs= statement.executeQuery(sql)) {
+
+            while (rs.next()){
+                names.add(rs.getString("spacecraft"));
+
+            }
+        } catch (SQLException e){
+            System.err.println(" Failure to find names: " +e.getMessage());
+
+        }
+
+        return names;
+    }
+
+    @Override
+    public Optional<MoonMission> findById(long missionId) {
+        String sql = "SELECT mission_id, spacecraft, launch_date, carrier_rocket, operator, mission_type, outcome FROM moon_mission WHERE mission_id = ?";
+
+        try( Connection connection= dataSource.getConnection();
+             PreparedStatement ps= connection.prepareStatement(sql)){
+
+            ps.setLong(1, missionId);
+
+            try(ResultSet rs = ps.executeQuery()){
+                if(rs.next()){
+                    //Map to MoonMission object:
+                    MoonMission mission= new MoonMission(
+                            rs.getLong("mission_id"),
+                            rs.getString("spacecraft"),
+                            rs.getObject("launch_date", LocalDate.class),
+                            rs.getString("carrier_rocket"),
+                            rs.getString("operator"),
+                            rs.getString("mission_type"),
+                            rs.getString("outcome")
+                    );
+
+                    return Optional.of(mission);
+                }
+            }
+        }catch (SQLException e){
+            System.err.println(" Failure in receiving mission per ID: " + e.getMessage());
+        }
+        return Optional.empty();
+    }
+
+    @Override
+    public int countByYear(int year) {
+        String sql = "SELECT COUNT(*) FROM moon_mission WHERE YEAR(launch_date) = ?";
+
+        try( Connection connection=dataSource.getConnection();
+        PreparedStatement ps=connection.prepareStatement(sql)){
+
+            ps.setInt(1, year);
+
+            try(ResultSet rs=ps.executeQuery()){
+                if(rs.next()){
+                    //Result is COUNT(*) column 1:
+                    return rs.getInt(1);
+                }
+            }
+        } catch (SQLException e ){
+            System.err.println(" Failure in counting missions per year: " + e.getMessage());
+        }
+        //return 0 if no results are found:
+        return 0;
+    }
+}
diff --git a/src/main/java/com/example/Main.java b/src/main/java/com/example/Main.java
index 6dc6fbd..5047f94 100644
--- a/src/main/java/com/example/Main.java
+++ b/src/main/java/com/example/Main.java
@@ -4,9 +4,17 @@
 import java.sql.DriverManager;
 import java.sql.SQLException;
 import java.util.Arrays;
+import java.util.List;
+import java.util.Optional;
+import java.util.Scanner;
 
 public class Main {
 
+    private AccountRepository accountRepository;
+    private MoonMissionRepository missionRepository;
+    private Scanner scanner;
+
+
     static void main(String[] args) {
         if (isDevMode(args)) {
             DevDatabaseInitializer.start();
@@ -31,6 +39,184 @@ public void run() {
             throw new RuntimeException(e);
         }
         //Todo: Starting point for your code
+
+        //create datasource:
+        DataSource dataSource=new SimpleDriverManagerDataSource(jdbcUrl,dbUser,dbPass);
+
+        //create Repositories by injecting datasource instead of  jdbcUrl, dbUser, dbPass.
+        this.accountRepository=new JdbcAccountRepository(dataSource);
+        this.missionRepository=new JdbcMoonMissionRepository(dataSource);
+        this.scanner=new Scanner(System.in);
+
+        if(handleLogin()){
+            showMainMenu();
+        }
+
+        scanner.close();
+    }
+
+
+
+    private boolean handleLogin() {
+        boolean loggedIn=false;
+        while(!loggedIn){
+            System.out.println("Username: ");
+            String username=scanner.nextLine();
+            System.out.println("Password: ");
+            String password= scanner.nextLine();
+
+            if (accountRepository.isValidLogin(username, password)){
+                System.out.println("Login successful! ");
+                loggedIn=true;
+            } else{
+                System.out.println(" Invalid username or password. Press 0 to exit or any other key to keep trying. ");
+                String choice= scanner.nextLine().trim();
+                if (choice.equals("0")){
+                    return false;
+                }
+            }
+        }
+        return true;
+    }
+
+    private void showMainMenu() {
+        boolean running= true;
+        while (running){
+            System.out.println("\n--- Main Menu ---");
+            System.out.println("1) List moon missions");
+            System.out.println("2) Get a moon mission by mission_id");
+            System.out.println("3) Count missions for a given year");
+            System.out.println("4) Create an account");
+            System.out.println("5) Update an account password");
+            System.out.println("6) Delete an account");
+            System.out.println("0) Exit");
+            System.out.print("Choose an option: ");
+
+            String choice=scanner.nextLine();
+
+            try{
+                switch(choice){
+                    case "1": listMoonMissions(); break;
+                    case "2": getMissionById(); break;
+                    case "3": countMissionsByYear(); break;
+                    case "4": createAccount(); break;
+                    case "5": updateAccountPassword(); break;
+                    case "6": deleteAccount(); break;
+                    case "0": running = false; break;
+                    default: System.out.println("Invalid option. Please try again."); break;
+
+                }
+            } catch (Exception e){
+                //to avoid numberFormat exceptions.
+                System.err.println(" An error occurred: " + e.getMessage());
+
+            }
+
+        }
+    }
+
+
+    private void listMoonMissions() {
+
+        List<String> names = missionRepository.findAllSpacecraftNames();
+        names.forEach(name-> System.out.println("- " + name));
+    }
+
+    private void getMissionById() {
+        System.out.println("Enter Mission ID: ");
+        try{
+            long id = Long.parseLong(scanner.nextLine());
+            Optional<MoonMission> mission = missionRepository.findById(id);
+
+            if (mission.isPresent()){
+                MoonMission m=mission.get();
+
+                System.out.println("\nMission details for ID " + m.missionId() + ":");
+                System.out.println("  Name: " + m.spacecraft());
+                System.out.println("  Date: " + m.launch_date());
+                System.out.println("  Outcome: " + m.outcome());
+                System.out.println("  Carrier: " + m.carrier_rocket());
+                System.out.println("  Operator: " + m.operator());
+                System.out.println("  Mission type: " + m.mission_type());
+            } else{
+                System.out.println("Mission not found.");
+            }
+
+
+        } catch(NumberFormatException e){
+            System.out.println("Invalid ID format.");
+        }
+    }
+
+    private void countMissionsByYear() {
+        System.out.println(" Enter launch year: ");
+
+        try{
+            int year= Integer.parseInt(scanner.nextLine());
+            int count= missionRepository.countByYear(year);
+
+            System.out.println(" There were " + count + " missions launched in " + year + ".");
+        } catch(NumberFormatException e){
+            System.out.println(" Invalid year format.");
+        }
+    }
+
+    private void createAccount(){
+        System.out.println("\n--- Create Account ---");
+        System.out.print("Enter first name: ");
+        String firstName = scanner.nextLine();
+        System.out.print("Enter last name: ");
+        String lastName = scanner.nextLine();
+        System.out.print("Enter SSN: ");
+        String ssn = scanner.nextLine();
+        System.out.print("Enter password: ");
+        String password = scanner.nextLine();
+
+        if(accountRepository.createAccount(firstName,lastName,ssn,password)){
+            System.out.println(" Account created successfully!");
+        } else{
+            System.out.println("failed to create account.");
+        }
+
+    }
+
+    private void updateAccountPassword(){
+        System.out.println("Enter user ID to update: ");
+
+        try{
+            long userId=Long.parseLong(scanner.nextLine());
+            System.out.println("Enter password: ");
+            String newPassword= scanner.nextLine();
+
+
+            if (accountRepository.updatePassword(userId,newPassword)){
+                System.out.println("Password updated successfully!");
+            } else{
+                System.out.println("failed to update password.");
+            }
+        } catch(NumberFormatException e ){
+            System.out.println("Invalid User ID format.");
+        }
+
+    }
+
+    private void deleteAccount(){
+        System.out.println(" Enter User ID to delete: ");
+
+        try{
+            long userId=Long.parseLong(scanner.nextLine());
+
+            if (accountRepository.deleteAccount(userId)){
+                System.out.println("Account deleted successfully!");
+            }else{
+                System.out.println("failed to delete account. User id not found.");
+            }
+
+        } catch (NumberFormatException e){
+            System.out.println("Invalid User ID format.");
+        }
+
+
     }
 
     /**
diff --git a/src/main/java/com/example/MoonMission.java b/src/main/java/com/example/MoonMission.java
new file mode 100644
index 0000000..4fbec23
--- /dev/null
+++ b/src/main/java/com/example/MoonMission.java
@@ -0,0 +1,13 @@
+package com.example;
+
+import java.time.LocalDate;
+
+public record MoonMission(
+        long missionId,
+        String spacecraft,
+       LocalDate launch_date,
+        String carrier_rocket,
+        String operator,
+        String mission_type,
+        String outcome
+) { }
diff --git a/src/main/java/com/example/MoonMissionRepository.java b/src/main/java/com/example/MoonMissionRepository.java
new file mode 100644
index 0000000..37a5045
--- /dev/null
+++ b/src/main/java/com/example/MoonMissionRepository.java
@@ -0,0 +1,18 @@
+package com.example;
+
+import java.util.List;
+import java.util.Optional;
+
+public interface MoonMissionRepository {
+
+    // List of all names:
+    List<String> findAllSpacecraftNames();
+
+    //Fetch assignment from ID:
+    Optional<MoonMission> findById(long missionId);
+
+    //Number of assignments per year:
+    int countByYear(int year);
+
+
+}
diff --git a/src/main/java/com/example/SimpleDriverManagerDataSource.java b/src/main/java/com/example/SimpleDriverManagerDataSource.java
new file mode 100644
index 0000000..c61d544
--- /dev/null
+++ b/src/main/java/com/example/SimpleDriverManagerDataSource.java
@@ -0,0 +1,30 @@
+package com.example;
+
+
+
+import java.sql.Connection;
+import java.sql.DriverManager;
+import java.sql.SQLException;
+
+public class SimpleDriverManagerDataSource implements DataSource {
+
+    private final String url;
+    private final String user;
+    private final String password;
+
+
+    public SimpleDriverManagerDataSource(String url, String user, String password) {
+        this.url = url;
+        this.user = user;
+        this.password = password;
+    }
+
+
+    @Override
+    public Connection getConnection() throws SQLException {
+
+        //We want the connection inside Datasource and not the Repository
+        return DriverManager.getConnection(url, user, password);
+
+    }
+}