TheCSharpAcademy · Frolikss · Jan 12, 2026
diff --git a/Frolikss.HabitTracker/DatabaseLogic/DatabaseLogic.csproj b/Frolikss.HabitTracker/DatabaseLogic/DatabaseLogic.csproj
@@ -0,0 +1,13 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+    <PropertyGroup>
+        <TargetFramework>net10.0</TargetFramework>
+        <ImplicitUsings>enable</ImplicitUsings>
+        <Nullable>enable</Nullable>
+    </PropertyGroup>
+
+    <ItemGroup>
+      <PackageReference Include="Microsoft.Data.Sqlite" Version="10.0.1" />
+    </ItemGroup>
+
+</Project>
diff --git a/Frolikss.HabitTracker/DatabaseLogic/DatabaseManager.cs b/Frolikss.HabitTracker/DatabaseLogic/DatabaseManager.cs
@@ -0,0 +1,328 @@
+using System.Globalization;
+using Microsoft.Data.Sqlite;
+
+namespace DatabaseLogic;
+
+public class Habit
+{
+    public int Id { get; set; }
+    public string Name { get; set; }
+    public string Units { get; set; }
+}
+
+public class Data
+{
+    public int Id { get; set; }
+    public int Quantity { get; set; }
+    public DateTime? Date { get; set; }
+    public Habit Habit { get; set; }
+
+    public Data()
+    {
+        Habit = new Habit();
+    }
+}
+
+public class DatabaseManager
+{
+    private static string dateFormat = "yyyy-MM-dd";
+    private string connectionString;
+    private string habitTypesTableName = "habit_types";
+    private string habitsTableName = "habit_logger";
+
+    public DatabaseManager(string connectionString)
+    {
+        this.connectionString = connectionString;
+
+        ExecuteQuery((command) =>
+        {
+            command.CommandText = (@$"
+                CREATE TABLE IF NOT EXISTS {habitTypesTableName}
+                (
+                    Id INTEGER PRIMARY KEY AUTOINCREMENT,
+                    Name TEXT,
+                    Units TEXT
+                );
+                CREATE TABLE IF NOT EXISTS {habitsTableName}
+                (
+                    Id INTEGER PRIMARY KEY AUTOINCREMENT,
+                    HabitTypeId INTEGER,
+                    Quantity INTEGER,
+                    Date TEXT,
+                    FOREIGN KEY (HabitTypeId) REFERENCES {habitTypesTableName}(Id)
+                );");
+        });
+        SeedHabitsTypes();
+        SeedHabitLogs();
+    }
+
+    void ExecuteQuery(Action<SqliteCommand>? configure = null)
+    {
+        try
+        {
+            using (var connection = new SqliteConnection(connectionString))
+            {
+                connection.Open();
+
+                using var pragma = connection.CreateCommand();
+                pragma.CommandText = @"PRAGMA foreign_keys = ON;";
+                pragma.ExecuteNonQuery();
+
+                var command = connection.CreateCommand();
+                configure?.Invoke(command);
+
+                command.ExecuteNonQuery();
+            }
+        }
+        catch (Exception err)
+        {
+            Console.WriteLine($"Error occured: {err.Message}");
+        }
+    }
+
+    void ExecuteReader(Action<SqliteCommand> configure)
+    {
+        using var connection = new SqliteConnection(connectionString);
+        connection.Open();
+
+        using var pragma = connection.CreateCommand();
+        pragma.CommandText = "PRAGMA foreign_keys = ON;";
+        pragma.ExecuteNonQuery();
+
+        using var command = connection.CreateCommand();
+        configure(command);
+    }
+
+    T ExecuteScalar<T>(Func<SqliteCommand, T> configure)
+    {
+        using var connection = new SqliteConnection(connectionString);
+        connection.Open();
+
+        using var pragma = connection.CreateCommand();
+        pragma.CommandText = "PRAGMA foreign_keys = ON;";
+        pragma.ExecuteNonQuery();
+
+        using var command = connection.CreateCommand();
+        return configure(command);
+    }
+
+    public int? AddHabit(Habit habit)
+    {
+        int? habitId = null;
+        var commandText = $@"
+            INSERT INTO {habitTypesTableName} (Name, Units)
+            VALUES (@name, @units);
+            SELECT last_insert_rowid();
+        ";
+
+        habitId = ExecuteScalar((command) =>
+        {
+            command.CommandText = commandText;
+
+            command.Parameters.AddWithValue("@name", habit.Name);
+            command.Parameters.AddWithValue("@units", habit.Units);
+
+            return Convert.ToInt32(command.ExecuteScalar());
+        });
+
+        return habitId;
+    }
+
+    public List<Habit> GetAllHabits()
+    {
+        var habits = new List<Habit>();
+
+        var commandText = $@"
+            SELECT * FROM {habitTypesTableName}
+        ";
+
+        ExecuteQuery((command) =>
+        {
+            command.CommandText = commandText;
+
+            using (var reader = command.ExecuteReader())
+            {
+                while (reader.Read())
+                {
+                    var habit = new Habit();
+
+                    var habitId = reader.GetInt32(0);
+                    var name = reader.GetString(1);
+                    var units = reader.GetString(2);
+
+                    habit.Id = habitId;
+                    habit.Name = name;
+                    habit.Units = units;
+
+                    habits.Add(habit);
+                }
+            }
+        });
+
+        return habits;
+    }
+
+    public void AddRecord(Data data)
+    {
+        var commandText = @$"
+            INSERT INTO {habitsTableName} (Quantity, Date, HabitTypeId)
+            VALUES (@quantity, @date, @habitTypeId);
+            ";
+
+        ExecuteQuery((command) =>
+        {
+            command.CommandText = commandText;
+            command.Parameters.AddWithValue("@quantity", data.Quantity);
+            command.Parameters.AddWithValue("@date", data.Date?.ToString(dateFormat));
+            command.Parameters.AddWithValue("@habitTypeId", data.Habit.Id);
+        });
+    }
+
+    public List<Data> GetAllRecords()
+    {
+        var allRecords = new List<Data>();
+
+        var commandText = @$"
+           SELECT
+                h.Id AS HabitLogId,
+                h.HabitTypeId,
+                h.Quantity,
+                h.Date,
+                t.Id AS HabitId,
+                t.Name AS HabitName,
+                t.Units AS HabitUnits
+            FROM {habitsTableName} h
+            INNER JOIN {habitTypesTableName} t
+                ON h.HabitTypeId = t.Id;
+        ";
+
+        ExecuteReader((command) =>
+        {
+            command.CommandText = commandText;
+
+            using (var reader = command.ExecuteReader())
+            {
+                while (reader.Read())
+                {
+                    var dataItem = new Data();
+
+                    var id = reader.GetInt32(reader.GetOrdinal("HabitLogId"));
+                    dataItem.Id = id;
+
+                    var habitId = reader.GetInt32(reader.GetOrdinal("HabitId"));
+                    dataItem.Habit.Id = habitId;
+
+                    var quantity = reader.GetInt32(reader.GetOrdinal("Quantity"));
+                    dataItem.Quantity = quantity;
+
+                    var stringDate = reader.GetString(reader.GetOrdinal("Date"));
+
+                    if (DateTime.TryParseExact(
+                            stringDate,
+                            dateFormat,
+                            CultureInfo.InvariantCulture,
+                            DateTimeStyles.None,
+                            out var parsedDate))
+                    {
+                        dataItem.Date = parsedDate;
+                    }
+
+                    var habitName = reader.GetString(reader.GetOrdinal("HabitName"));
+                    dataItem.Habit.Name = habitName;
+
+                    var habitUnits = reader.GetString(reader.GetOrdinal("HabitUnits"));
+                    dataItem.Habit.Units = habitUnits;
+
+                    allRecords.Add(dataItem);
+                }
+            }
+        });
+
+        return allRecords;
+    }
+
+    public void UpdateRecord(Data data)
+    {
+        var commandText = $@"
+                UPDATE {habitsTableName}
+                SET Quantity = @quantity,
+                    Date = @date,
+                    HabitTypeId = @habitTypeId
+                WHERE Id = @id
+            ";
+
+        ExecuteQuery((command) =>
+        {
+            command.CommandText = commandText;
+            command.Parameters.AddWithValue("@quantity", data.Quantity);
+            command.Parameters.AddWithValue("@date", data.Date?.ToString(dateFormat));
+            command.Parameters.AddWithValue("@habitTypeId", data.Habit.Id);
+            command.Parameters.AddWithValue("@id", data.Id);
+        });
+    }
+
+    public void DeleteRecord(int recordId)
+    {
+        var commandText = $@"
+            DELETE FROM {habitsTableName}
+            WHERE id = @id
+        ";
+
+        ExecuteQuery((command) =>
+        {
+            command.CommandText = commandText;
+            command.Parameters.AddWithValue("@id", recordId);
+        });
+    }
+
+    void SeedHabitsTypes()
+    {
+        ExecuteQuery(command =>
+        {
+            command.CommandText = @"
+            INSERT OR IGNORE INTO habit_types (Id, Name, Units) VALUES
+                (1, 'Water', 'liters'),
+                (2, 'Running', 'km'),
+                (3, 'Reading', 'pages'),
+                (4, 'Workout', 'minutes');
+        ";
+        });
+    }
+
+    void SeedHabitLogs()
+    {
+        var count = ExecuteScalar<int>(command =>
+        {
+            command.CommandText = $"SELECT COUNT(*) FROM {habitsTableName};";
+            return Convert.ToInt32(command.ExecuteScalar());
+        });
+
+        if (count > 0)
+            return;
+
+        var random = new Random();
+        var startDate = DateTime.Today.AddDays(-100);
+
+        for (int i = 0; i < 100; i++)
+        {
+            var habitTypeId = random.Next(1, 5);
+            var quantity = random.Next(1, 11);
+            var date = startDate.AddDays(i);
+
+            ExecuteQuery(command =>
+            {
+                command.CommandText = $@"
+                INSERT INTO {habitsTableName}
+                    (HabitTypeId, Quantity, Date)
+                VALUES
+                    (@habitTypeId, @quantity, @date);
+            ";
+
+                command.Parameters.AddWithValue("@habitTypeId", habitTypeId);
+                command.Parameters.AddWithValue("@quantity", quantity);
+                command.Parameters.AddWithValue("@date", date.ToString(dateFormat));
+            });
+        }
+    }
+
+}
diff --git a/Frolikss.HabitTracker/HabitTracker.sln b/Frolikss.HabitTracker/HabitTracker.sln
@@ -0,0 +1,22 @@
+
+Microsoft Visual Studio Solution File, Format Version 12.00
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "HabitTracker", "HabitTracker\HabitTracker.csproj", "{1D4177F4-2BC8-48DE-8FDD-FE05D56EF9C3}"
+EndProject
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "DatabaseLogic", "DatabaseLogic\DatabaseLogic.csproj", "{D5BCE2B7-7E94-4E88-8AEE-D4ADD19AFBC1}"
+EndProject
+Global
+	GlobalSection(SolutionConfigurationPlatforms) = preSolution
+		Debug|Any CPU = Debug|Any CPU
+		Release|Any CPU = Release|Any CPU
+	EndGlobalSection
+	GlobalSection(ProjectConfigurationPlatforms) = postSolution
+		{1D4177F4-2BC8-48DE-8FDD-FE05D56EF9C3}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{1D4177F4-2BC8-48DE-8FDD-FE05D56EF9C3}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{1D4177F4-2BC8-48DE-8FDD-FE05D56EF9C3}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{1D4177F4-2BC8-48DE-8FDD-FE05D56EF9C3}.Release|Any CPU.Build.0 = Release|Any CPU
+		{D5BCE2B7-7E94-4E88-8AEE-D4ADD19AFBC1}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{D5BCE2B7-7E94-4E88-8AEE-D4ADD19AFBC1}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{D5BCE2B7-7E94-4E88-8AEE-D4ADD19AFBC1}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{D5BCE2B7-7E94-4E88-8AEE-D4ADD19AFBC1}.Release|Any CPU.Build.0 = Release|Any CPU
+	EndGlobalSection
+EndGlobal
diff --git a/Frolikss.HabitTracker/HabitTracker/.DS_Store b/Frolikss.HabitTracker/HabitTracker/.DS_Store
diff --git a/Frolikss.HabitTracker/HabitTracker/HabitTracker.csproj b/Frolikss.HabitTracker/HabitTracker/HabitTracker.csproj
@@ -0,0 +1,14 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+    <PropertyGroup>
+        <OutputType>Exe</OutputType>
+        <TargetFramework>net10.0</TargetFramework>
+        <ImplicitUsings>enable</ImplicitUsings>
+        <Nullable>enable</Nullable>
+    </PropertyGroup>
+
+    <ItemGroup>
+      <ProjectReference Include="..\DatabaseLogic\DatabaseLogic.csproj" />
+    </ItemGroup>
+
+</Project>