final add function

src/team2.cs

@@ -0,0 +1,151 @@
+using System;
+using Microsoft.Data.Sqlite;
+
+class AddRecords
+{
+    public static void AddAuthor(SqliteConnection connection, string name, string surname, DateTime dateOfBirth)
+    {
+        string query = "INSERT OR IGNORE INTO Authors (Name, Surname, DateOfBirth) VALUES (@name, @surname, @dob);";
+        using (var command = new SqliteCommand(query, connection))
+        {
+            command.Parameters.AddWithValue("@name", name);
+            command.Parameters.AddWithValue("@surname", surname);
+            command.Parameters.AddWithValue("@dob", dateOfBirth.ToString("yyyy-MM-dd"));
+            command.ExecuteNonQuery();
+            Console.WriteLine("Author added successfully.");
+        }
+    }
+
+    public static void AddPublisher(SqliteConnection connection, string name, string state)
+    {
+        string query = "INSERT OR IGNORE INTO Publisher (Name, State) VALUES (@name, @state);";
+        using (var command = new SqliteCommand(query, connection))
+        {
+            command.Parameters.AddWithValue("@name", name);
+            command.Parameters.AddWithValue("@state", state);
+            command.ExecuteNonQuery();
+        }
+    }
+
+    public static void AddBook(SqliteConnection connection, string name, int authorId, int publisherId, int year, int total, int available)
+    {
+        string query = @"INSERT OR IGNORE INTO Books (Name, AuthorID, PublisherID, YearOfRelease, Total, Available) 
+                         VALUES (@name, @author, @publisher, @year, @total, @available);";
+
+        using (var command = new SqliteCommand())
+        {
+            command.Connection = connection;
+            try
+            {
+                // Check author exists
+                command.CommandText = "SELECT 1 FROM Authors WHERE ID = @Aid;";
+                command.Parameters.Clear();
+                command.Parameters.AddWithValue("@Aid", authorId);
+                using (var reader = command.ExecuteReader())
+                {
+                    if (!reader.HasRows)
+                    {
+                        Console.WriteLine($"Author with ID {authorId} does not exist.");
+                        return;
+                    }
+                }
+
+                // Check publisher exists
+                command.CommandText = "SELECT 1 FROM Publisher WHERE ID = @Pid;";
+                command.Parameters.Clear();
+                command.Parameters.AddWithValue("@Pid", publisherId);
+                using (var reader = command.ExecuteReader())
+                {
+                    if (!reader.HasRows)
+                    {
+                        Console.WriteLine($"Publisher with ID {publisherId} does not exist.");
+                        return;
+                    }
+                }
+
+                // Insert book
+                command.CommandText = query;
+                command.Parameters.Clear();
+                command.Parameters.AddWithValue("@name", name);
+                command.Parameters.AddWithValue("@year", year);
+                command.Parameters.AddWithValue("@total", total);
+                command.Parameters.AddWithValue("@available", available);
+                command.Parameters.AddWithValue("@author", authorId);
+                command.Parameters.AddWithValue("@publisher", publisherId);
+                command.ExecuteNonQuery();
+
+            }
+            catch (Exception ex)
+            {
+                // Log and return so the exception doesn't bubble to the caller
+                Console.WriteLine($"AddBook failed: {ex.Message}");
+                return;
+            }
+        }
+    }
+
+    public static void AddUser(SqliteConnection connection, string name, string surname)
+    {
+        string query = "INSERT OR IGNORE INTO Users (Name, Surname) VALUES (@name, @surname);";
+        using (var command = new SqliteCommand(query, connection))
+        {
+            command.Parameters.AddWithValue("@name", name);
+            command.Parameters.AddWithValue("@surname", surname);
+            command.ExecuteNonQuery();
+        }
+    }
+
+    public static void AddBorrowedBookRecord(SqliteConnection connection, int bookId, int userId, DateTime borrowedDate, int days = 30)
+    {
+        string returnDue = borrowedDate.AddDays(days).ToString("yyyy-MM-dd");
+        string query = @"INSERT OR IGNORE INTO Borrows (DateOfBorrow, ReturnDue, UserID, BookID) 
+                         VALUES (@borrowed, @due, @user, @book);";
+
+        using (var command = new SqliteCommand())
+        {
+            command.Connection = connection;
+            try
+            {
+                // Check user exists
+                command.CommandText = "SELECT 1 FROM Users WHERE ID = @Uid;";
+                command.Parameters.Clear();
+                command.Parameters.AddWithValue("@Uid", userId);
+                using (var reader = command.ExecuteReader())
+                {
+                    if (!reader.HasRows)
+                    {
+                        Console.WriteLine($"User with ID {userId} does not exist.");
+                        return;
+                    }
+                }
+
+                // Check book exists
+                command.CommandText = "SELECT 1 FROM Books WHERE ID = @Bid;";
+                command.Parameters.Clear();
+                command.Parameters.AddWithValue("@Bid", bookId);
+                using (var reader = command.ExecuteReader())
+                {
+                    if (!reader.HasRows)
+                    {
+                        Console.WriteLine($"Book with ID {bookId} does not exist.");
+                        return;
+                    }
+                }
+
+                // Insert borrow record
+                command.CommandText = query;
+                command.Parameters.Clear();
+                command.Parameters.AddWithValue("@borrowed", borrowedDate.ToString("yyyy-MM-dd"));
+                command.Parameters.AddWithValue("@due", returnDue);
+                command.Parameters.AddWithValue("@user", userId);
+                command.Parameters.AddWithValue("@book", bookId);
+                command.ExecuteNonQuery();
+            }
+            catch (Exception ex)
+            {
+                Console.WriteLine($"AddBorrowedBookRecord failed: {ex.Message}");
+                return;
+            }
+        }
+    }
+}