#include "screens/launchpad/OnboardingTour.h"

#include "core/logging/Logger.h"
#include "storage/repositories/SettingsRepository.h"

#include <QCloseEvent>
#include <QHBoxLayout>
#include <QLabel>
#include <QPointer>
#include <QPushButton>
#include <QStackedWidget>
#include <QVBoxLayout>

namespace fincept::screens {

namespace {
constexpr const char* kTourTag = "OnboardingTour";
constexpr const char* kSeenKey = "onboarding.tour_seen";

// Process-wide guard so re-entrant show_for() calls don't stack two
// dialogs. Pointer cleared via QObject's destroyed signal in show_for.
QPointer<OnboardingTour> s_active_tour;
} // namespace

bool OnboardingTour::has_been_seen() {
    auto r = SettingsRepository::instance().get(kSeenKey);
    return r.is_ok() && r.value() == "true";
}

void OnboardingTour::mark_seen() {
    auto r = SettingsRepository::instance().set(kSeenKey, "true");
    if (r.is_err())
        LOG_WARN(kTourTag, QString("Failed to set %1: %2").arg(kSeenKey, QString::fromStdString(r.error())));
}

void OnboardingTour::reset_seen() {
    auto r = SettingsRepository::instance().set(kSeenKey, "false");
    if (r.is_err())
        LOG_WARN(kTourTag, QString("Failed to reset %1: %2").arg(kSeenKey, QString::fromStdString(r.error())));
}

void OnboardingTour::show_for(QWidget* parent) {
    if (s_active_tour) {
        s_active_tour->raise();
        s_active_tour->activateWindow();
        return;
    }
    auto* tour = new OnboardingTour(parent);
    tour->setAttribute(Qt::WA_DeleteOnClose);
    s_active_tour = tour;
    QObject::connect(tour, &QObject::destroyed, []() { s_active_tour = nullptr; });
    tour->show();
}

OnboardingTour::OnboardingTour(QWidget* parent) : QDialog(parent) {
    setWindowTitle(tr("Welcome to Fincept Terminal"));
    setModal(true);
    setSizeGripEnabled(false);
    resize(560, 360);
    build_ui();
    retranslateUi();
    update_buttons();
}

void OnboardingTour::build_ui() {
    auto* root = new QVBoxLayout(this);
    root->setContentsMargins(24, 24, 24, 16);
    root->setSpacing(16);

    heading_ = new QLabel(this);
    QFont tf = heading_->font();
    // App font is pixel-sized (pointSizeF() == -1), so scale whichever metric
    // is actually set — multiplying a -1 point size yields a negative value
    // that setPointSizeF rejects with a warning.
    if (tf.pixelSize() > 0)
        tf.setPixelSize(qRound(tf.pixelSize() * 1.4));
    else if (tf.pointSizeF() > 0)
        tf.setPointSizeF(tf.pointSizeF() * 1.4);
    tf.setBold(true);
    heading_->setFont(tf);
    root->addWidget(heading_);

    // Build the four steps with empty labels — retranslateUi() fills in the
    // text so language switches re-apply it. build_step() caches the labels
    // into step_labels_ in declared order.
    steps_ = new QStackedWidget(this);
    steps_->addWidget(build_step({}, {}, {}));
    steps_->addWidget(build_step({}, {}, {}));
    steps_->addWidget(build_step({}, {}, {}));
    steps_->addWidget(build_step({}, {}, {}));
    step_count_ = steps_->count();
    root->addWidget(steps_, /*stretch=*/1);

    progress_ = new QLabel(this);
    progress_->setAlignment(Qt::AlignCenter);
    root->addWidget(progress_);

    auto* button_row = new QHBoxLayout;
    btn_skip_ = new QPushButton(tr("Skip"), this);
    btn_back_ = new QPushButton(tr("Back"), this);
    btn_next_ = new QPushButton(tr("Next"), this);
    btn_next_->setDefault(true);
    button_row->addWidget(btn_skip_);
    button_row->addStretch();
    button_row->addWidget(btn_back_);
    button_row->addWidget(btn_next_);
    root->addLayout(button_row);

    connect(btn_skip_, &QPushButton::clicked, this, &OnboardingTour::on_skip);
    connect(btn_back_, &QPushButton::clicked, this, &OnboardingTour::on_back);
    connect(btn_next_, &QPushButton::clicked, this, &OnboardingTour::on_next);
}

QWidget* OnboardingTour::build_step(const QString& title, const QString& body, const QString& tip) {
    auto* w = new QWidget;
    auto* l = new QVBoxLayout(w);
    l->setContentsMargins(0, 0, 0, 0);
    l->setSpacing(10);

    auto* h = new QLabel(title, w);
    QFont hf = h->font();
    hf.setBold(true);
    // See note above — scale the pixel size when the font is pixel-defined.
    if (hf.pixelSize() > 0)
        hf.setPixelSize(qRound(hf.pixelSize() * 1.15));
    else if (hf.pointSizeF() > 0)
        hf.setPointSizeF(hf.pointSizeF() * 1.15);
    h->setFont(hf);
    l->addWidget(h);

    auto* b = new QLabel(body, w);
    b->setWordWrap(true);
    l->addWidget(b);

    auto* t = new QLabel(tip, w);
    t->setWordWrap(true);
    QFont tf = t->font();
    tf.setItalic(true);
    t->setFont(tf);
    l->addWidget(t);

    l->addStretch();

    // Cache the three labels so retranslateUi() can re-apply per-step text.
    step_labels_.append({h, b, t});
    return w;
}

void OnboardingTour::changeEvent(QEvent* event) {
    if (event->type() == QEvent::LanguageChange)
        retranslateUi();
    QDialog::changeEvent(event);
}

void OnboardingTour::retranslateUi() {
    setWindowTitle(tr("Welcome to Fincept Terminal"));
    if (heading_)
        heading_->setText(tr("A 30-second tour"));

    // Step text, indexed by step order. Guarded so partial construction is safe.
    if (step_labels_.size() > 0 && step_labels_[0].title) {
        step_labels_[0].title->setText(tr("Command bar (Ctrl+\\)"));
        step_labels_[0].body->setText(tr("Type a function code or verb to do anything in the terminal — "
                                         "e.g. \"AAPL\", \"layout switch \\\"Morning\\\"\", or "
                                         "\"link panel red\". Press Ctrl+K for a fuzzy palette of every "
                                         "action."));
        step_labels_[0].tip->setText(tr("Tip: type \"?\" to list available actions for whatever you "
                                        "type next."));
    }
    if (step_labels_.size() > 1 && step_labels_[1].title) {
        step_labels_[1].title->setText(tr("Link panels with a colour"));
        step_labels_[1].body->setText(tr("Click the coloured dot in any panel header to add it to a link "
                                         "group. Panels in the same group share their selected symbol "
                                         "across windows — pick AAPL in a watchlist and your charts, "
                                         "research, and trading panels all switch."));
        step_labels_[1].tip->setText(tr("Tip: groups are shared across windows, not just the active "
                                        "one."));
    }
    if (step_labels_.size() > 2 && step_labels_[2].title) {
        step_labels_[2].title->setText(tr("Tear off panels into new windows"));
        step_labels_[2].body->setText(tr("Right-click a panel tab → \"Tear off into new window\" to spawn "
                                         "a fresh frame on the next monitor. Or drag a panel to another "
                                         "frame's tab bar to move it. Each frame keeps its own dock "
                                         "layout — save the whole arrangement as a named layout when "
                                         "you've got it the way you like."));
        step_labels_[2].tip->setText(tr("Tip: Ctrl+Shift+N opens a fresh window on your next "
                                        "monitor."));
    }
    if (step_labels_.size() > 3 && step_labels_[3].title) {
        step_labels_[3].title->setText(tr("Settings & shortcuts"));
        step_labels_[3].body->setText(tr("Open Settings (gear icon) to tune theme, hotkeys, telemetry "
                                         "opt-in, and broker credentials. Hotkeys are rebindable — "
                                         "every action in the registry can be assigned a key."));
        step_labels_[3].tip->setText(tr("Tip: F11 toggles fullscreen on the focused window."));
    }

    if (btn_skip_)
        btn_skip_->setText(tr("Skip"));
    if (btn_back_)
        btn_back_->setText(tr("Back"));
    // btn_next_ text is managed by update_buttons() (depends on current step).
    update_buttons();
}

void OnboardingTour::on_next() {
    if (!steps_)
        return;
    if (current_step_ + 1 >= step_count_) {
        on_finish();
        return;
    }
    ++current_step_;
    steps_->setCurrentIndex(current_step_);
    update_buttons();
}

void OnboardingTour::on_back() {
    if (!steps_ || current_step_ == 0)
        return;
    --current_step_;
    steps_->setCurrentIndex(current_step_);
    update_buttons();
}

void OnboardingTour::on_skip() {
    finished_ = true;
    mark_seen();
    accept();
}

void OnboardingTour::on_finish() {
    finished_ = true;
    mark_seen();
    accept();
}

void OnboardingTour::update_buttons() {
    if (!btn_back_ || !btn_next_)
        return;
    btn_back_->setEnabled(current_step_ > 0);
    const bool last = (current_step_ + 1 >= step_count_);
    btn_next_->setText(last ? tr("Got it!") : tr("Next"));
    if (progress_)
        progress_->setText(tr("Step %1 of %2").arg(current_step_ + 1).arg(step_count_));
}

void OnboardingTour::closeEvent(QCloseEvent* e) {
    // Treat OS close as "skip" so the user doesn't get hit with the tour
    // again on next launch.
    if (!finished_)
        mark_seen();
    QDialog::closeEvent(e);
}

} // namespace fincept::screens