<?php
/**
 * app/modules/connections/save.php
 *
 * Speichert / aktualisiert eine Netzwerkverbindung
 * (Basis-Implementierung - kann erweitert werden)
 */

// Nur POST
if ($_SERVER['REQUEST_METHOD'] !== 'POST') {
    header('Location: ?module=connections&action=list');
    exit;
}

// =========================
// Daten einlesen
// =========================
$connId = (int)($_POST['id'] ?? 0);
$portAType = $_POST['port_a_type'] ?? 'device';
$portAId = (int)($_POST['port_a_id'] ?? 0);
$portBType = $_POST['port_b_type'] ?? 'device';
$portBId = (int)($_POST['port_b_id'] ?? 0);
$vlanConfig = $_POST['vlan_config'] ?? '';
$comment = trim($_POST['comment'] ?? '');

$normalizePortType = static function (string $value): string {
    $map = [
        'device' => 'device',
        'device_ports' => 'device',
        'module' => 'module',
        'module_ports' => 'module',
        'outlet' => 'outlet',
        'network_outlet_ports' => 'outlet',
        'patchpanel' => 'patchpanel',
        'floor_patchpanel' => 'patchpanel',
        'floor_patchpanel_ports' => 'patchpanel',
    ];
    $key = strtolower(trim($value));
    return $map[$key] ?? $key;
};

$portAType = $normalizePortType((string)$portAType);
$portBType = $normalizePortType((string)$portBType);

$isTopologyPairAllowed = static function (string $typeA, string $typeB): bool {
    $allowed = ['device' => true, 'module' => true, 'outlet' => true, 'patchpanel' => true];
    if (!isset($allowed[$typeA]) || !isset($allowed[$typeB])) {
        return false;
    }
    if ($typeA === 'patchpanel' || $typeB === 'patchpanel') {
        return ($typeA === 'patchpanel' && in_array($typeB, ['patchpanel', 'outlet'], true))
            || ($typeB === 'patchpanel' && in_array($typeA, ['patchpanel', 'outlet'], true));
    }
    return true;
};

// =========================
// Validierung (einfach)
// =========================
$errors = [];

if ($portAId <= 0 || $portBId <= 0) {
    $errors[] = "Beide Ports sind erforderlich";
}
if (!$isTopologyPairAllowed($portAType, $portBType)) {
    $errors[] = "Patchpanel-Ports duerfen nur mit Patchpanel-Ports oder Netzwerkdosen-Ports verbunden werden";
}

$otherConnections = $sql->get(
    "SELECT id, port_a_type, port_a_id, port_b_type, port_b_id
     FROM connections
     WHERE id <> ?",
    "i",
    [$connId]
);

$isEndpointUsed = static function (string $endpointType, int $endpointId) use ($otherConnections, $normalizePortType): bool {
    if ($endpointId <= 0) {
        return false;
    }
    foreach ((array)$otherConnections as $row) {
        $typeA = $normalizePortType((string)($row['port_a_type'] ?? ''));
        $idA = (int)($row['port_a_id'] ?? 0);
        if ($typeA === $endpointType && $idA === $endpointId) {
            return true;
        }

        $typeB = $normalizePortType((string)($row['port_b_type'] ?? ''));
        $idB = (int)($row['port_b_id'] ?? 0);
        if ($typeB === $endpointType && $idB === $endpointId) {
            return true;
        }
    }
    return false;
};

if ($isEndpointUsed($portAType, $portAId)) {
    $errors[] = "Port an Endpunkt A ist bereits in Verwendung";
}
if ($isEndpointUsed($portBType, $portBId)) {
    $errors[] = "Port an Endpunkt B ist bereits in Verwendung";
}

if (!empty($errors)) {
    $_SESSION['error'] = implode(', ', $errors);
    $_SESSION['validation_errors'] = $errors;
    $redirectUrl = $connId ? "?module=connections&action=edit&id=$connId" : "?module=connections&action=edit";
    header("Location: $redirectUrl");
    exit;
}

// =========================
// In DB speichern
// =========================
$vlanJson = $vlanConfig ? json_encode(explode(',', $vlanConfig)) : null;

if ($connId > 0) {
    // UPDATE
    $sql->set(
        "UPDATE connections SET port_a_type = ?, port_a_id = ?, port_b_type = ?, port_b_id = ?, vlan_config = ?, comment = ? WHERE id = ?",
        "sisissi",
        [$portAType, $portAId, $portBType, $portBId, $vlanJson, $comment, $connId]
    );
} else {
    $connectionTypeId = (int)($sql->single(
        "SELECT id FROM connection_types ORDER BY id LIMIT 1",
        "",
        []
    )['id'] ?? 0);

    if ($connectionTypeId <= 0) {
        $connectionTypeId = (int)$sql->set(
            "INSERT INTO connection_types (name, medium, duplex, line_style, comment) VALUES (?, ?, ?, ?, ?)",
            "sssss",
            ['Default', 'copper', 'custom', 'solid', 'Auto-created by connections/save'],
            true
        );
    }

    if ($connectionTypeId <= 0) {
        $_SESSION['error'] = "Kein Verbindungstyp verfuegbar";
        $_SESSION['validation_errors'] = ["Kein Verbindungstyp verfuegbar"];
        header("Location: ?module=connections&action=edit");
        exit;
    }

    // INSERT
    $sql->set(
        "INSERT INTO connections (connection_type_id, port_a_type, port_a_id, port_b_type, port_b_id, vlan_config, comment) VALUES (?, ?, ?, ?, ?, ?, ?)",
        "isisiss",
        [$connectionTypeId, $portAType, $portAId, $portBType, $portBId, $vlanJson, $comment]
    );
}

$_SESSION['success'] = "Verbindung gespeichert";

// =========================
// Redirect
// =========================
header('Location: ?module=connections&action=list');
exit;