Add local UDP discovery and invitation delivery for chat clients

tools/chatgui/src/invitedialog.cpp

@@ -14,14 +14,19 @@
 #include <QClipboard>
 #include <QApplication>
 #include <QSignalBlocker>
+#include <QPointer>
+#include <QtEndian>
 #include <cstring>
 
 extern "C" {
 #include "../../../src/chat/invite_build.h"
 #include "../../../src/chat/chat_join.h"
+#include "../../../src/chat/chat_local.h"
 #include "../../../lib/mem.h"
 }
 
+static QPointer<ShareInviteDialog> s_shareInviteDialog;
+
 ShareInviteDialog::ShareInviteDialog(const QString& channelId, DbManager* db, QWidget* parent)
     : QDialog(parent)
     , m_channelId(channelId)
@@ -30,6 +35,7 @@ ShareInviteDialog::ShareInviteDialog(const QString& channelId, DbManager* db, QW
     setWindowTitle(QCoreApplication::translate("ChatGui", "Invite link"));
     setMinimumSize(420, 560);
     setModal(true);
+    s_shareInviteDialog = this;
 
     auto *layout = new QVBoxLayout(this);
     layout->setSpacing(12);
@@ -38,7 +44,7 @@ ShareInviteDialog::ShareInviteDialog(const QString& channelId, DbManager* db, QW
     expiry->setWordWrap(true);
     layout->addWidget(expiry);
 
-    auto *nodeLabel = new QLabel(QCoreApplication::translate("ChatGui", "Entry node:"), this);
+    auto *nodeLabel = new QLabel(QCoreApplication::translate("ChatGui", "Connect via"), this);
     nodeLabel->setStyleSheet("font-size: 12px; color: palette(window-text);");
 
     m_nodeCombo = new QComboBox(this);
@@ -72,6 +78,32 @@ ShareInviteDialog::ShareInviteDialog(const QString& channelId, DbManager* db, QW
     linkRow->addWidget(copyBtn);
     layout->addLayout(linkRow);
 
+    m_localRow = new QWidget(this);
+    auto* localLayout = new QVBoxLayout(m_localRow);
+    localLayout->setContentsMargins(0, 0, 0, 0);
+    localLayout->addWidget(new QLabel(QCoreApplication::translate("ChatGui", "Devices on the local network:"), m_localRow));
+    auto* deviceRow = new QHBoxLayout();
+    m_devices = new QComboBox(m_localRow);
+    m_devices->setObjectName(QStringLiteral("localDevices"));
+    m_sendLocal = new QPushButton(QCoreApplication::translate("ChatGui", "Send to device"), m_localRow);
+    m_sendLocal->setObjectName(QStringLiteral("sendLocalInvite"));
+    m_sendLocal->setEnabled(false);
+    deviceRow->addWidget(m_devices, 1); deviceRow->addWidget(m_sendLocal);
+    localLayout->addLayout(deviceRow);
+    layout->addWidget(m_localRow); m_localRow->hide();
+    m_delivery = new QLabel(this);
+    m_delivery->setWordWrap(true); layout->addWidget(m_delivery);
+    connect(m_sendLocal, &QPushButton::clicked, this, &ShareInviteDialog::sendLocalInvite);
+    connect(m_devices, QOverload<int>::of(&QComboBox::currentIndexChanged), this, [this] { updateLocalSend(); });
+    gui_bridge_set_local_devices_cb([](const uint8_t* data, int len) {
+        if (s_shareInviteDialog) s_shareInviteDialog->onLocalDevices(data, len);
+    });
+    gui_bridge_set_local_delivery_cb([](const uint8_t* data, int len) {
+        if (s_shareInviteDialog) s_shareInviteDialog->onLocalDelivery(data, len);
+    });
+    if (gui_bridge_is_uasync_ready() && gui_bridge_get_inst())
+        gui_bridge_post_uasync_fn(chat_local_peers_trampoline, gui_bridge_get_inst());
+
     m_qrLabel = new QLabel(this);
     m_qrLabel->setAlignment(Qt::AlignCenter);
     m_qrLabel->setMinimumSize(180, 180);
@@ -86,11 +118,11 @@ ShareInviteDialog::ShareInviteDialog(const QString& channelId, DbManager* db, QW
 
     /* колбэки результатов (по образцу JoinDialog) */
     gui_bridge_set_invite_link_ready_cb([](const char* chId, int chIdLen, uint64_t requestId, const char* link) {
-        ShareInviteDialog* dlg = qobject_cast<ShareInviteDialog*>(QApplication::activeModalWidget());
+        ShareInviteDialog* dlg = s_shareInviteDialog;
         if (dlg) dlg->onLinkReady(chId, chIdLen, requestId, link);
     });
     gui_bridge_set_invite_candidates_cb([](const char* chId, int chIdLen, const uint8_t* data, int len) {
-        ShareInviteDialog* dlg = qobject_cast<ShareInviteDialog*>(QApplication::activeModalWidget());
+        ShareInviteDialog* dlg = s_shareInviteDialog;
         if (dlg) dlg->onCandidates(chId, chIdLen, data, len);
     });
 
@@ -103,6 +135,9 @@ ShareInviteDialog::ShareInviteDialog(const QString& channelId, DbManager* db, QW
 }
 
 ShareInviteDialog::~ShareInviteDialog() {
+    s_shareInviteDialog = nullptr;
+    gui_bridge_set_local_devices_cb(nullptr);
+    gui_bridge_set_local_delivery_cb(nullptr);
     gui_bridge_set_invite_link_ready_cb(nullptr);
     gui_bridge_set_invite_candidates_cb(nullptr);
 }
@@ -127,6 +162,7 @@ void ShareInviteDialog::requestLink(uint64_t targetNodeId) {
     req->request_id = m_requestId = ++nextRequestId;
     req->target_node_id = targetNodeId;
     m_linkEdit->setText(QString());
+    updateLocalSend();
     m_linkEdit->setPlaceholderText(QCoreApplication::translate("ChatGui", "Generating link..."));
     m_qrLabel->clear();
     gui_bridge_post_uasync_fn(chat_invite_build_link_trampoline, req);
@@ -134,6 +170,7 @@ void ShareInviteDialog::requestLink(uint64_t targetNodeId) {
 
 void ShareInviteDialog::setLink(const QString& link) {
     m_linkEdit->setText(link);
+    updateLocalSend();
     QImage qrImage = generateQRCode(link);
     if (!qrImage.isNull())
         m_qrLabel->setPixmap(QPixmap::fromImage(qrImage).scaled(
@@ -195,9 +232,72 @@ void ShareInviteDialog::onLinkReady(const char* chId, int chIdLen, uint64_t requ
     if (cid != m_channelId) return;
     if (!link || link[0] == '\0') {
         m_linkEdit->setText(QString());
+        updateLocalSend();
         m_linkEdit->setPlaceholderText(QCoreApplication::translate("ChatGui", "Failed to build the link (see log)"));
         m_qrLabel->clear();
         return;
     }
     setLink(QString::fromUtf8(link));
 }
+
+void ShareInviteDialog::updateLocalSend() {
+    m_sendLocal->setEnabled(!m_localRequest && m_devices->currentIndex() >= 0 && !m_linkEdit->text().isEmpty());
+}
+
+void ShareInviteDialog::onLocalDevices(const uint8_t* data, int len) {
+    if (len < 2) { GUI_ERROR("discovery: invalid device list bytes=%d", len); return; }
+    struct Device { quint64 id; QString name; };
+    QList<Device> devices;
+    int count = qFromBigEndian<quint16>(data), offset = 2;
+    for (int i = 0; i < count; i++) {
+        if (offset + 9 > len || offset + 9 + data[offset + 8] > len) {
+            GUI_ERROR("discovery: truncated device list bytes=%d offset=%d", len, offset); return;
+        }
+        int nameLen = data[offset + 8];
+        devices.append({qFromBigEndian<quint64>(data + offset), QString::fromUtf8((const char*)data + offset + 9, nameLen)});
+        offset += 9 + nameLen;
+    }
+    if (offset != len) { GUI_ERROR("discovery: trailing device list bytes=%d", len - offset); return; }
+    auto selected = m_devices->currentData();
+    QSignalBlocker blocker(m_devices);
+    m_devices->clear();
+    for (const auto& device : devices) {
+        const QString suffix = QString::number(device.id, 16).right(6);
+        m_devices->addItem(device.name + QStringLiteral(" [%1]").arg(suffix), QVariant::fromValue(device.id));
+    }
+    int index = m_devices->findData(selected);
+    if (index >= 0) m_devices->setCurrentIndex(index);
+    m_localRow->setVisible(!devices.isEmpty()); updateLocalSend();
+}
+
+void ShareInviteDialog::sendLocalInvite() {
+    QByteArray link = m_linkEdit->text().toUtf8();
+    if (m_localRequest || m_devices->currentIndex() < 0 || link.isEmpty()) return;
+    if (!gui_bridge_is_uasync_ready() || !gui_bridge_get_inst()) {
+        GUI_ERROR("discovery: core stopped before local send");
+        m_delivery->setText(QCoreApplication::translate("ChatGui", "Could not deliver invitation")); return;
+    }
+    if (link.size() > LOCAL_TRANSPORT_DATA_MAX) {
+        GUI_ERROR("discovery: invitation too long bytes=%d", (int)link.size());
+        m_delivery->setText(QCoreApplication::translate("ChatGui", "Could not deliver invitation")); return;
+    }
+    auto* req = (struct chat_local_send_request*)u_calloc(1, sizeof(struct chat_local_send_request));
+    if (!req) { GUI_ERROR("discovery: send request allocation failed"); return; }
+    static uint64_t nextRequest = 0;
+    req->inst = gui_bridge_get_inst(); req->peer_id = m_devices->currentData().toULongLong();
+    req->request_id = m_localRequest = ++nextRequest;
+    memcpy(req->link, link.constData(), (size_t)link.size());
+    m_delivery->setText(QCoreApplication::translate("ChatGui", "Sending invitation…")); updateLocalSend();
+    gui_bridge_post_uasync_fn(chat_local_send_trampoline, req);
+}
+
+void ShareInviteDialog::onLocalDelivery(const uint8_t* data, int len) {
+    if (len != 17 || data[16] > LOCAL_DELIVERY_FORBIDDEN) { GUI_ERROR("discovery: invalid delivery response bytes=%d", len); return; }
+    if (!m_localRequest || qFromBigEndian<quint64>(data) != m_localRequest) return;
+    m_localRequest = 0;
+    if (data[16] == LOCAL_DELIVERY_FORBIDDEN) m_delivery->setText(QCoreApplication::translate("ChatGui",
+        "Receiving invitations is forbidden. Enable it in the recipient device's settings."));
+    else m_delivery->setText(QCoreApplication::translate("ChatGui",
+        data[16] == LOCAL_DELIVERY_RECEIVED ? "Invitation delivered" : "Could not deliver invitation"));
+    updateLocalSend();
+}