<?php
/**
 * app/api/connections.php
 *
 * API für Netzwerkverbindungen (Port ↔ Port)
 * - Laden der Topologie
 * - Anlegen / Bearbeiten / Löschen von Verbindungen
 * - Unterstützt freie Verbindungstypen (Kupfer, LWL, BNC, Token Ring, etc.)
 */

require_once __DIR__ . '/../bootstrap.php';

header('Content-Type: application/json');

// TODO: Single-User-Auth prüfen
// if (!$_SESSION['user']) { http_response_code(403); exit; }

$action = $_GET['action'] ?? 'load';

/* =========================
 * Router
 * ========================= */

switch ($action) {

    case 'load':
        loadConnections($sql);
        break;

    case 'save':
        saveConnection($sql);
        break;

    case 'delete':
        deleteConnection($sql);
        break;

    default:
        http_response_code(400);
        echo json_encode(['error' => 'Unbekannte Aktion']);
        break;
}

/* =========================
 * Aktionen
 * ========================= */

/**
 * Lädt alle Geräte + Ports + Verbindungen für eine Netzwerkansicht
 */
function loadConnections($sql)
{
    $contextId = $_GET['context_id'] ?? null;

    if (!$contextId) {
        http_response_code(400);
        echo json_encode(['error' => 'context_id fehlt']);
        return;
    }

    // TODO: Kontext definieren (Standort, Rack, Floor, gesamtes Netz)

    /* ---------- Geräte ---------- */
    $devices = $sql->get(
        "SELECT id, name, device_type_id, pos_x, pos_y
         FROM devices
         WHERE context_id = ?",
        "i",
        [$contextId]
    );

    /* ---------- Ports ---------- */
    $ports = $sql->get(
        "SELECT p.id, p.device_id, p.name, p.port_type_id
         FROM ports p
         JOIN devices d ON d.id = p.device_id
         WHERE d.context_id = ?",
        "i",
        [$contextId]
    );

    /* ---------- Verbindungen ---------- */
    $connections = $sql->get(
        "SELECT
            c.id,
            c.connection_type_id,
            c.port_a_id,
            c.port_b_id,
            c.vlan,
            c.mode,
            c.comment
         FROM connections c",
        "",
        []
    );

    echo json_encode([
        'devices' => $devices,
        'ports' => $ports,
        'connections' => $connections
    ]);
}

/**
 * Speichert eine Verbindung (neu oder Update)
 */
function saveConnection($sql)
{
    $data = json_decode(file_get_contents('php://input'), true);

    if (!$data) {
        http_response_code(400);
        echo json_encode(['error' => 'Ungültige JSON-Daten']);
        return;
    }

    // TODO: Validierung
    // - port_a_id vorhanden
    // - port_b_id vorhanden
    // - Verbindungstyp erlaubt

    if (!empty($data['id'])) {
        // UPDATE
        $rows = $sql->set(
            "UPDATE connections
             SET connection_type_id = ?, port_a_id = ?, port_b_id = ?, vlan = ?, mode = ?, comment = ?
             WHERE id = ?",
            "iiiissi",
            [
                $data['connection_type_id'],
                $data['port_a_id'],
                $data['port_b_id'],
                $data['vlan'],
                $data['mode'],
                $data['comment'],
                $data['id']
            ]
        );

        echo json_encode([
            'status' => 'updated',
            'rows' => $rows
        ]);
    } else {
        // INSERT
        $id = $sql->set(
            "INSERT INTO connections
                (connection_type_id, port_a_id, port_b_id, vlan, mode, comment)
             VALUES (?, ?, ?, ?, ?, ?)",
            "iiiiss",
            [
                $data['connection_type_id'],
                $data['port_a_id'],
                $data['port_b_id'],
                $data['vlan'],
                $data['mode'],
                $data['comment']
            ],
            true
        );

        echo json_encode([
            'status' => 'created',
            'id' => $id
        ]);
    }
}

/**
 * Löscht eine Verbindung
 */
function deleteConnection($sql)
{
    $id = $_GET['id'] ?? null;

    if (!$id) {
        http_response_code(400);
        echo json_encode(['error' => 'ID fehlt']);
        return;
    }

    // TODO: Prüfen, ob Verbindung existiert

    $rows = $sql->set(
        "DELETE FROM connections WHERE id = ?",
        "i",
        [$id]
    );

    echo json_encode([
        'status' => 'deleted',
        'rows' => $rows
    ]);
}