<?php
$databaseFile = 'mydatabase.db';

try {
    $db = new PDO("sqlite:" . $databaseFile);
    $db->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);

    // Check if the User table exists
    $result = $db->query("SELECT name FROM sqlite_master WHERE type='table' AND name='User'");
    $userTableExists = $result->fetchColumn();

    if (!$userTableExists) {
        // Initialize the database structure
        $db->exec("
            CREATE TABLE User (
                id INTEGER PRIMARY KEY AUTOINCREMENT,
                vorname TEXT NOT NULL,
                nachname TEXT NOT NULL,
                username TEXT UNIQUE NOT NULL,
                password TEXT NOT NULL
            )
        ");

        $db->exec("
            CREATE TABLE Restaurant (
                id INTEGER PRIMARY KEY AUTOINCREMENT,
                name TEXT NOT NULL,
                maps_link TEXT
            )
        ");

        $db->exec("
            CREATE TABLE Bewertung (
                id INTEGER PRIMARY KEY AUTOINCREMENT,
                fk_user_id INTEGER NOT NULL,
                fk_restaurant_id INTEGER NOT NULL,
                bewertung INTEGER NOT NULL CHECK (bewertung BETWEEN 0 AND 10),
                bewertung_str TEXT,
                FOREIGN KEY (fk_user_id) REFERENCES User(id),
                FOREIGN KEY (fk_restaurant_id) REFERENCES Restaurant(id)
            )
        ");

        echo "<p style='color:green;'>Database initialized successfully!</p>";
    } else {
        // Optionally, you can add a message indicating the database already exists
        // echo "<p style='color:blue;'>Database already exists.</p>";
    }

} catch (PDOException $e) {
    die("Database connection failed: " . $e->getMessage());
}

function sanitize_input($data) {
    $data = trim($data);
    $data = stripslashes($data);
    $data = htmlspecialchars($data);
    return $data;
}
?>