Program.cs

using Microsoft.Data.Sqlite;
using Spectre.Console;
using System.Globalization;

string connectionString = @"Data Source=habit-Tracker.db";

CreateDatabase();

MainMenu();

void MainMenu()
    {
    var isMenuRunning = true;

    while (isMenuRunning)
        {
        Console.Clear();
        var usersChoice = AnsiConsole.Prompt(
            new SelectionPrompt<string>()
                .Title("What would you like to do?")
                .AddChoices(
                    "Add Habit",
                    "Delete Habit",
                    "Update Habit",
                    "Add Record",
                    "Delete Record",
                    "View Records",
                    "Update Record",
                    "Quit"
                )
        );

        switch (usersChoice)
            {
            case "Add Habit":
            AddHabit();
            break;
            case "Delete Habit":
            DeleteHabit();
            break;
            case "Update Habit":
            UpdateHabit();
            break;
            case "Add Record":
            AddRecord();
            break;
            case "Delete Record":
            DeleteRecord();
            break;
            case "View Records":
            GetRecords();
            break;
            case "Update Record":
            UpdateRecord();
            break;
            case "Quit":
            Console.WriteLine("Goodbye");
            isMenuRunning = false;
            break;
            default:
            Console.WriteLine("Invalid choice. Please choose one of the above");
            break;
            }
        }
    }

bool IsTableEmpty(string tableName)
    {
    using (var connection = new SqliteConnection(connectionString))
        {
        connection.Open();

        using (var command = connection.CreateCommand())
            {
            command.CommandText = $"SELECT COUNT(*) FROM {tableName}";
            long count = (long)command.ExecuteScalar();

            return count == 0;
            }
        }
    }

void SeedData()
    {
    bool recordsTableEmpty = IsTableEmpty("records");
    bool habitsTableEmpty = IsTableEmpty("habits");

    if (!recordsTableEmpty || !habitsTableEmpty)
        return;

    string[] habitNames =
    {
        "Reading",
        "Running",
        "Chocolate",
        "Drinking Water",
        "Glasses of Wine",
    };
    string[] habitUnits = { "Pages", "Meters", "Grams", "Mililiters", "Mililiters" };

    string[] dates = GenerateRandomDates(100);
    int[] quantities = GenerateRandomQuantities(100, 0, 2000);

    using (var connection = new SqliteConnection(connectionString))
        {
        connection.Open();

        for (int i = 0; i < habitNames.Length; i++)
            {
            var insertSql =
                $"INSERT INTO habits (Name, MeasurementUnit) VALUES ('{habitNames[i]}', '{habitUnits[i]}');";
            var command = new SqliteCommand(insertSql, connection);

            command.ExecuteNonQuery();
            }

        for (int i = 0; i < 100; i++)
            {
            var insertSql =
                $"INSERT INTO records (Date, Quantity, HabitId) VALUES ('{dates[i]}', {quantities[i]}, {GetRandomHabitId()});";
            var command = new SqliteCommand(insertSql, connection);

            command.ExecuteNonQuery();
            }
        }
    }

int[] GenerateRandomQuantities(int count, int min, int max)
    {
    Random random = new Random();
    int[] quantities = new int[count];

    for (int i = 0; i < count; i++)
        {
        // max + 1 because the top range is excluded
        quantities[i] = random.Next(min, max + 1);
        }

    return quantities;
    }

string[] GenerateRandomDates(int count)
    {
    DateTime startDate = new DateTime(2023, 1, 1);
    DateTime endDate = new DateTime(2024, 12, 31);
    TimeSpan range = endDate - startDate;

    string[] randomDateStrings = new string[count];
    Random random = new Random();

    for (int i = 0; i < count; i++)
        {
        int daysToAdd = random.Next(0, (int)range.TotalDays);
        DateTime randomDate = startDate.AddDays(daysToAdd);
        randomDateStrings[i] = randomDate.ToString("dd-MM-yy");
        }

    return randomDateStrings;
    }

int GetRandomHabitId()
    {
    Random random = new Random();
    return random.Next(1, 6);
    }
void CreateDatabase()
    {
    using (var connection = new SqliteConnection(connectionString))
        {
        using (var tableCmd = connection.CreateCommand())
            {
            connection.Open();

            tableCmd.CommandText =
                @"CREATE TABLE IF NOT EXISTS records (
                    Id INTEGER PRIMARY KEY AUTOINCREMENT,
                    Date TEXT,
                    Quantity INTEGER,
                    HabitId INTEGER,
                    FOREIGN KEY(habitId) REFERENCES habits(Id) ON DELETE CASCADE
                )";
            tableCmd.ExecuteNonQuery();

            tableCmd.CommandText =
                @"CREATE TABLE IF NOT EXISTS habits (
                    Id INTEGER PRIMARY KEY AUTOINCREMENT,
                    Name TEXT,
                    MeasurementUnit Text
                )";
            tableCmd.ExecuteNonQuery();
            }
        }
    //new code
    SeedData();
    }

void AddHabit()
    {
    Console.Clear();
    Console.WriteLine("Adding a new Habit:\n");
    var name = AnsiConsole.Ask<string>("Habit's name:");
    while (string.IsNullOrEmpty(name))
        {
        name = AnsiConsole.Ask<string>("Habit's name can't be empty. Try again:");
        }

    var unit = AnsiConsole.Ask<string>("What's the habit's unit of measurement?");
    while (string.IsNullOrEmpty(unit))
        {
        unit = AnsiConsole.Ask<string>("Unit of measurement can't be empty. Try again:");
        }
    using (var connection = new SqliteConnection(connectionString))
        {
        connection.Open();
        var tableCmd = connection.CreateCommand();

        tableCmd.CommandText =
            $"INSERT INTO habits(Name, MeasurementUnit) VALUES('{name}', '{unit}')";

        tableCmd.ExecuteNonQuery();
        }
    }

void DeleteHabit()
    {
    Console.Clear();
    Console.WriteLine("Deleting Habit:\n");
    GetHabits();

    var id = GetNumber("\nPlease type the id of the habit you want to delete.");

    using (var connection = new SqliteConnection(connectionString))
        {
        using (var command = connection.CreateCommand())
            {
            connection.Open();

            command.CommandText = @$"DELETE FROM habits WHERE Id = {id}";
            command.ExecuteNonQuery();
            }
        }
    Console.Clear();
    Console.WriteLine("Habit Deleted (Press any Key to continue)");
    GetHabits();
    Console.ReadKey();
    }

void UpdateHabit()
    {
    Console.Clear();
    Console.WriteLine("Updating Habit:\n");
    GetHabits();
    int id = GetNumber("\nPlease type the id of the habit you want to update.");

    string name = "";
    bool updateName = AnsiConsole.Confirm("\nUpdate name?");
    if (updateName)
        {
        name = AnsiConsole.Ask<string>("Habit's new name:");
        while (string.IsNullOrEmpty(name))
            {
            name = AnsiConsole.Ask<string>("Habit's name can't be empty. Try again:");
            }
        }

    string unit = "";
    bool updateUnit = AnsiConsole.Confirm("Update Unit of Measurement?");
    if (updateUnit)
        {
        unit = AnsiConsole.Ask<string>("Habit's Unit of Measurement:");
        while (string.IsNullOrEmpty(unit))
            {
            unit = AnsiConsole.Ask<string>("Habit's unit can't be empty. Try again:");
            }
        }

    string query =
        updateName && updateUnit
            ? $"UPDATE habits SET Name = '{name}', MeasurementUnit = '{unit}' WHERE Id = {id}"
        : updateName && !updateUnit ? $"UPDATE habits SET Name = '{name}' WHERE Id = {id}"
        : $"UPDATE habits SET MeasurementUnit = '{unit}' WHERE Id = {id}";

    using (var connection = new SqliteConnection(connectionString))
        {
        connection.Open();
        var tableCmd = connection.CreateCommand();

        tableCmd.CommandText = query;

        tableCmd.ExecuteNonQuery();
        }
    Console.WriteLine("\n Record updated (Press anu key to continue)");
    QueryAndDisplaySingleRecord(id);
    }

void GetHabits()
    {
    List<Habit> habits = new();

    using (var connection = new SqliteConnection(connectionString))
        {
        connection.Open();
        var tableCmd = connection.CreateCommand();
        tableCmd.CommandText = "SELECT * FROM Habits";

        using (SqliteDataReader reader = tableCmd.ExecuteReader())
            {
            if (reader.HasRows)
                {
                while (reader.Read())
                    try
                        {
                        habits.Add(
                            new Habit(reader.GetInt32(0), reader.GetString(1), reader.GetString(2))
                        );
                        }
                    catch (Exception ex)
                        {
                        Console.WriteLine($"Error getting record: {ex.Message}. ");
                        }
                }
            else
                {
                Console.WriteLine("No rows found");
                }
            }
        }

    ViewHabits(habits);
    }

void ViewHabits(List<Habit> habits)
    {
    var table = new Table();
    table.AddColumn("Id");
    table.AddColumn("Name");
    table.AddColumn("Unit of Measurement");

    foreach (var habit in habits)
        {
        table.AddRow(habit.Id.ToString(), habit.Name, habit.UnitOfMeasurement);
        }

    AnsiConsole.Write(table);
    }

void AddRecord()
    {
    Console.Clear();
    Console.WriteLine("Adding a new Record\n");
    string date = GetDate(
        "\nEnter the date (format : dd-mm-yy) or insert 0 to Go Back to Main Menu:\n"
    );

    GetHabits();
    int habitId = GetNumber("\nPlease enter the id of the habit for this record");

    int quantity = GetNumber(
        "\nPlease enter quantity (no decimals or negatives allowed) or enter 0 to go back to Main Menu."
    );

    Console.Clear();
    using (var connection = new SqliteConnection(connectionString))
        {
        connection.Open();
        var tableCmd = connection.CreateCommand();

        tableCmd.CommandText =
            $"INSERT INTO records(date, quantity, habitId) VALUES('{date}', {quantity}, {habitId})";

        tableCmd.ExecuteNonQuery();
        }
    }

string GetDate(string message)
    {
    Console.WriteLine(message);
    string dateInput = Console.ReadLine();

    if (dateInput == "0")
        MainMenu();

    while (
        !DateTime.TryParseExact(
            dateInput,
            "dd-MM-yy",
            CultureInfo.InvariantCulture,
            DateTimeStyles.None,
            out _
        )
    )
        {
        Console.WriteLine("\n\nInvalid date. (Format: dd-mm-yy). PLease try again\n\n");
        dateInput = Console.ReadLine();
        }

    return dateInput;
    }

int GetNumber(string message)
    {
    Console.WriteLine(message);
    string numberInput = Console.ReadLine();

    if (numberInput == "0")
        MainMenu();

    int output = 0;
    while (!int.TryParse(numberInput, out output) || Convert.ToInt32(numberInput) < 0)
        {
        Console.WriteLine("\n\nInvalid number. Try again. \n\n");
        numberInput = Console.ReadLine();
        }

    return output;
    }

void GetRecords()
    {
    List<RecordWithHabit> records = new();

    using (var connection = new SqliteConnection(connectionString))
        {
        connection.Open();
        var tableCmd = connection.CreateCommand();
        tableCmd.CommandText =
            @"
    SELECT records.Id, records.Date, records.Quantity, records.HabitId, habits.Name AS HabitName, habits.MeasurementUnit
    FROM records
    INNER JOIN habits ON records.HabitId = habits.Id";

        using (SqliteDataReader reader = tableCmd.ExecuteReader())
            {
            if (reader.HasRows)
                {
                while (reader.Read())
                    try
                        {
                        records.Add(
                            new RecordWithHabit(
                                reader.GetInt32(0),
                                DateTime.ParseExact(
                                    reader.GetString(1),
                                    "dd-MM-yy",
                                    CultureInfo.InvariantCulture
                                ),
                                reader.GetInt32(2),
                                reader.GetString(4),
                                reader.GetString(5)
                            )
                        );
                        }
                    catch (FormatException ex)
                        {
                        Console.WriteLine(
                            $"Error parsing date: {ex.Message}. Skipping this record."
                        );
                        }
                }
            else
                {
                Console.WriteLine("No rows found");
                }
            }
        }

    ViewRecords(records);
    Console.WriteLine("Press any key to continue:");
    Console.ReadKey();
    }

void ViewRecords(List<RecordWithHabit> records)
    {
    var table = new Table();
    table.AddColumn("Id");
    table.AddColumn("Date");
    table.AddColumn("Amount");
    table.AddColumn("Habit");

    foreach (var record in records)
        {
        table.AddRow(
            record.Id.ToString(),
            record.Date.ToString("D"),
            $"{record.Quantity} {record.MeasurementUnit}",
            record.HabitName.ToString()
        );
        }

    AnsiConsole.Write(table);
    }

void DeleteRecord()
    {
    GetRecords();

    var id = GetNumber("Please type the id of the record you want to delete.");

    using (var connection = new SqliteConnection(connectionString))
        {
        using (var command = connection.CreateCommand())
            {
            connection.Open();

            command.CommandText = @$"DELETE FROM walkingHabit WHERE Id = {id}";
            command.ExecuteNonQuery();
            }
        }
    }

void UpdateRecord()
    {
    Console.Clear();
    GetRecords();
    int id = GetNumber("Please type the id of the record you want to select:");
    QueryAndDisplaySingleRecord(id);

    string date = "";
    bool updateDate = AnsiConsole.Confirm("Update date?");
    if (updateDate)
        {
        date = GetDate(
            "\nEnter the date (format : dd-mm-yy) or insert 0 to Go Back to Main Menu:\n"
        );
        }

    int quantity = 0;
    bool updateQuantity = AnsiConsole.Confirm("Update quantity?");
    if (updateQuantity)
        {
        quantity = GetNumber(
            "\nPlease enter quantity (no decimals or negatives allowed) or enter 0 to go back to Main Menu."
        );
        }

    string query =
        updateDate && updateQuantity
            ? $"UPDATE records SET Date = '{date}', Quantity = {quantity} WHERE Id = {id}"
        : updateDate && !updateQuantity ? $"UPDATE records SET Date = '{date}' WHERE Id = {id}"
        : $"UPDATE records SET Quantity = {quantity} WHERE Id = {id}";

    using (var connection = new SqliteConnection(connectionString))
        {
        connection.Open();
        var tableCmd = connection.CreateCommand();
        tableCmd.CommandText = query;
        tableCmd.ExecuteNonQuery();
        Console.WriteLine("\nUpdate completed:\n");
        QueryAndDisplaySingleRecord(id);
        }
    }

void QueryAndDisplaySingleRecord(int id)
    {
    Console.Clear();

    using (var connection = new SqliteConnection(connectionString))
        {
        connection.Open();
        var command = connection.CreateCommand();
        command.CommandText =
            @$"SELECT records.Id, records.Date, records.Quantity, habits.Name AS HabitName, habits.MeasurementUnit
                                     FROM records
                                     INNER JOIN habits ON records.HabitId = habits.Id
                                     WHERE records.Id = {id}";

        using (var reader = command.ExecuteReader())
            {
            if (reader.Read())
                {
                var record = new RecordWithHabit(
                    reader.GetInt32(0),
                    DateTime.ParseExact(
                        reader.GetString(1),
                        "dd-MM-yy",
                        CultureInfo.InvariantCulture
                    ),
                    reader.GetInt32(2),
                    reader.GetString(3),
                    reader.GetString(4)
                );

                var table = new Table();
                table.AddColumn("Id");
                table.AddColumn("Date");
                table.AddColumn("Quantity");
                table.AddColumn("Habit");
                table.AddColumn("Unit");

                table.AddRow(
                    record.Id.ToString(),
                    record.Date.ToString("dd-MM-yy"),
                    record.Quantity.ToString(),
                    record.HabitName,
                    record.MeasurementUnit
                );

                AnsiConsole.Write(table);
                }
            else
                {
                Console.WriteLine("No record found with the given ID.");
                }
            }
        }
    return;
    }

record RecordWithHabit(
    int Id,
    DateTime Date,
    int Quantity,
    string HabitName,
    string MeasurementUnit
);

record Habit(int Id, string Name, string UnitOfMeasurement);