<?php
// Verbindet sich zur MySQL-Datenbank
function db_connect() {
    $conn = new mysqli(DB_HOST, DB_USER, DB_PASS, DB_NAME);
    if ($conn->connect_error) {
        die("Verbindung fehlgeschlagen: " . $conn->connect_error);
    }
    return $conn;
}

// Holt alle Geräte aus der Datenbank
function get_all_devices() {
    $conn = db_connect();
    $sql = "SELECT * FROM devices";
    $result = $conn->query($sql);
    
    $devices = [];
    while ($row = $result->fetch_assoc()) {
        $devices[] = $row;
    }
    
    $conn->close();
    return $devices;
}

// Holt ein Gerät nach ID aus der Datenbank
function get_device_by_id($id) {
    $conn = db_connect();
    $sql = "SELECT * FROM devices WHERE id = ?";
    $stmt = $conn->prepare($sql);
    $stmt->bind_param("i", $id);
    $stmt->execute();
    
    $result = $stmt->get_result();
    $device = $result->fetch_assoc();
    
    $conn->close();
    return $device;
}

// Fügt ein neues Gerät in die Datenbank ein
function add_device($imei, $phone_number, $gps_position, $battery_level) {
    $conn = db_connect();
    $sql = "INSERT INTO devices (imei, phone_number, gps_position, battery_level) VALUES (?, ?, ?, ?)";
    $stmt = $conn->prepare($sql);
    $stmt->bind_param("sssd", $imei, $phone_number, $gps_position, $battery_level);
    $stmt->execute();
    
    $conn->close();
    return $stmt->insert_id;
}

// Aktualisiert ein Gerät in der Datenbank
function update_device($id, $gps_position, $battery_level) {
    $conn = db_connect();
    $sql = "UPDATE devices SET gps_position = ?, battery_level = ? WHERE id = ?";
    $stmt = $conn->prepare($sql);
    $stmt->bind_param("sdi", $gps_position, $battery_level, $id);
    $stmt->execute();
    
    $conn->close();
}

// Löscht ein Gerät aus der Datenbank
function delete_device($id) {
    $conn = db_connect();
    $sql = "DELETE FROM devices WHERE id = ?";
    $stmt = $conn->prepare($sql);
    $stmt->bind_param("i", $id);
    $stmt->execute();
    
    $conn->close();
}