#include "invitedialog.h"
#include "qrcode_utils.h"
#include "../db/db_manager.h"
#include "../transport/gui_bridge.h"
#include "debug_ui.h"

#include <QVBoxLayout>
#include <QHBoxLayout>
#include <QLineEdit>
#include <QPushButton>
#include <QLabel>
#include <QComboBox>
#include <QClipboard>
#include <QApplication>
#include <QSignalBlocker>
#include <cstring>

extern "C" {
#include "../../../src/chat/invite_build.h"
#include "../../../lib/mem.h"
}

ShareInviteDialog::ShareInviteDialog(const QString& channelId, DbManager* db, QWidget* parent)
    : QDialog(parent)
    , m_channelId(channelId)
    , m_db(db)
{
    setWindowTitle(QString::fromUtf8("Пригласительная ссылка"));
    setMinimumSize(420, 560);
    setModal(true);

    auto *layout = new QVBoxLayout(this);
    layout->setSpacing(12);

    auto *nodeLabel = new QLabel(QString::fromUtf8("Узел входа:"), this);
    nodeLabel->setStyleSheet("font-size: 12px; color: palette(window-text);");

    m_nodeCombo = new QComboBox(this);
    m_nodeCombo->setStyleSheet(
        "QComboBox { border: 1px solid palette(mid); border-radius: 4px;"
        " padding: 6px 10px; font-size: 13px; background: palette(base); }");

    auto *nodeRow = new QHBoxLayout();
    nodeRow->setSpacing(8);
    nodeRow->addWidget(nodeLabel);
    nodeRow->addWidget(m_nodeCombo, 1);
    layout->addLayout(nodeRow);

    m_linkEdit = new QLineEdit(this);
    m_linkEdit->setReadOnly(true);
    m_linkEdit->setPlaceholderText(QString::fromUtf8("Генерация ссылки..."));
    m_linkEdit->setStyleSheet("padding: 6px; font-family: monospace;");

    auto *copyBtn = new QPushButton(QString::fromUtf8("Копировать"), this);
    connect(copyBtn, &QPushButton::clicked, this, [this]() {
        QClipboard* cb = QApplication::clipboard();
        cb->setText(m_linkEdit->text(), QClipboard::Clipboard);
        if (cb->supportsSelection())
            cb->setText(m_linkEdit->text(), QClipboard::Selection);
        m_linkEdit->setFocus();
    });

    auto *linkRow = new QHBoxLayout();
    linkRow->setSpacing(8);
    linkRow->addWidget(m_linkEdit, 1);
    linkRow->addWidget(copyBtn);
    layout->addLayout(linkRow);

    m_qrLabel = new QLabel(this);
    m_qrLabel->setAlignment(Qt::AlignCenter);
    m_qrLabel->setMinimumSize(180, 180);
    layout->addWidget(m_qrLabel, 0, Qt::AlignCenter);

    auto *closeBtn = new QPushButton("OK", this);
    connect(closeBtn, &QPushButton::clicked, this, &QDialog::accept);
    layout->addWidget(closeBtn, 0, Qt::AlignRight);

    connect(m_nodeCombo, QOverload<int>::of(&QComboBox::currentIndexChanged),
            this, &ShareInviteDialog::onNodeSelected);

    /* колбэки результатов (по образцу JoinDialog) */
    gui_bridge_set_invite_link_ready_cb([](const char* chId, int chIdLen, const char* link) {
        ShareInviteDialog* dlg = qobject_cast<ShareInviteDialog*>(QApplication::activeModalWidget());
        if (dlg) dlg->onLinkReady(chId, chIdLen, 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());
        if (dlg) dlg->onCandidates(chId, chIdLen, data, len);
    });

    /* запросить кандидатов; линк строится после их прихода */
    QByteArray chBytes = m_channelId.toUtf8();
    gui_bridge_post_uasync_fn(chat_invite_candidates_trampoline, u_strdup(chBytes.constData()));
}

ShareInviteDialog::~ShareInviteDialog() {
    gui_bridge_set_invite_link_ready_cb(nullptr);
    gui_bridge_set_invite_candidates_cb(nullptr);
}

void ShareInviteDialog::onNodeSelected(int index) {
    if (index < 0) return;
    qulonglong nodeId = m_nodeCombo->itemData(index).toULongLong();
    requestLink((uint64_t)nodeId);
}

void ShareInviteDialog::requestLink(uint64_t targetNodeId) {
    struct chat_invite_build_req* req = (struct chat_invite_build_req*)u_malloc(sizeof(*req));
    if (!req) {
        GUI_ERROR("invite: requestLink — alloc failed");
        return;
    }
    memset(req, 0, sizeof(*req));
    QByteArray chBytes = m_channelId.toUtf8();
    strncpy(req->ch_id, chBytes.constData(), sizeof(req->ch_id) - 1);
    req->target_node_id = targetNodeId;
    m_linkEdit->setText(QString());
    m_linkEdit->setPlaceholderText(QString::fromUtf8("Генерация ссылки..."));
    m_qrLabel->clear();
    gui_bridge_post_uasync_fn(chat_invite_build_link_trampoline, req);
}

void ShareInviteDialog::setLink(const QString& link) {
    m_linkEdit->setText(link);
    QImage qrImage = generateQRCode(link);
    if (!qrImage.isNull())
        m_qrLabel->setPixmap(QPixmap::fromImage(qrImage).scaled(
            180, 180, Qt::KeepAspectRatio, Qt::SmoothTransformation));
    adjustSize();
}

void ShareInviteDialog::onCandidates(const char* chId, int chIdLen, const uint8_t* data, int len) {
    QString cid = QString::fromUtf8(chId, chIdLen);
    if (cid != m_channelId) return;
    if (!data || len < 10) return;

    uint64_t autoId = 0;
    memcpy(&autoId, data, 8);
    uint16_t count = 0;
    memcpy(&count, data + 8, 2);

    if (autoId == 0) {
        m_linkEdit->setText(QString());
        m_linkEdit->setPlaceholderText(QString::fromUtf8("Не удалось определить узел (см. лог)"));
        return;
    }

    auto nodeLabel = [this](uint64_t nid) {
        QString name = m_db ? m_db->getDisplayName(nid) : QString();
        if (name.isEmpty())
            name = QString("0x%1").arg(nid, 16, 16, QChar('0'));
        return name;
    };

    /* блокируем сигналы, чтобы не перезапрашивать линк при добавлении пунктов */
    QSignalBlocker blocker(m_nodeCombo);
    m_nodeCombo->clear();

    /* пункт 0 — узел, найденный авто-выбором */
    m_nodeCombo->addItem(nodeLabel(autoId) + QString::fromUtf8(" (auto)"),
                         QVariant::fromValue((qulonglong)autoId));

    /* остальные узлы (пропуская авто), свой помечаем (self) */
    int off = 10;
    for (int i = 0; i < (int)count && off + 8 <= len; i++) {
        uint64_t nid = 0;
        memcpy(&nid, data + off, 8);
        off += 8;
        if (nid == autoId) continue;
        QString label = nodeLabel(nid);
        if (m_db && nid == m_db->myNodeId())
            label += QString::fromUtf8(" (self)");
        m_nodeCombo->addItem(label, QVariant::fromValue((qulonglong)nid));
    }

    /* строим линк для авто-узла (сигнал заблокирован) */
    requestLink(autoId);
}

void ShareInviteDialog::onLinkReady(const char* chId, int chIdLen, const char* link) {
    QString cid = QString::fromUtf8(chId, chIdLen);
    if (cid != m_channelId) return;
    if (!link || link[0] == '\0') {
        m_linkEdit->setText(QString());
        m_linkEdit->setPlaceholderText(QString::fromUtf8("Не удалось собрать ссылку (см. лог)"));
        m_qrLabel->clear();
        return;
    }
    setLink(QString::fromUtf8(link));
}