#pragma once
// SettingsScreen.h — top-level settings shell. Hosts a left-nav + QStackedWidget
// of sub-section widgets. All section state and UI lives in *Section.h/.cpp
// files in this directory; this class only owns the navigation, the MCP
// event subscription that triggers a cross-section reload, and the centralised
// language-change handler that rebuilds every section so their newly
// constructed widgets pick up the active QTranslator.

#include "core/events/EventBus.h"
#include "screens/common/IStatefulScreen.h"

#include <QHideEvent>
#include <QLabel>
#include <QLineEdit>
#include <QList>
#include <QPushButton>
#include <QShowEvent>
#include <QStackedWidget>
#include <QVariantMap>
#include <QWidget>

#include <functional>

namespace fincept::screens {

class SettingsScreen : public QWidget, public IStatefulScreen {
    Q_OBJECT
  public:
    explicit SettingsScreen(QWidget* parent = nullptr);

    void restore_state(const QVariantMap& state) override;
    QVariantMap save_state() const override;
    QString state_key() const override { return "settings"; }

  protected:
    void showEvent(QShowEvent* e) override;
    void hideEvent(QHideEvent* e) override;
    void changeEvent(QEvent* e) override;

  private:
    QStackedWidget* sections_ = nullptr;
    QWidget* nav_ = nullptr;
    QLabel* nav_title_ = nullptr;

    void refresh_theme();
    void retranslateUi();

    /// Re-wire signals from section instances to external services. Called
    /// after every section rebuild (language change) so the wiring survives
    /// the destruction of the old section widgets.
    void wire_section_signals();

    /// Rebuild every section widget by constructing fresh instances via the
    /// stored factories. Preserves the current section index. Each rebuilt
    /// section picks up the active QTranslator at construction time.
    void rebuild_sections_for_language_change();

    /// Nav button → source key map used to retranslate button labels and
    /// scope headers without rebuilding the nav.
    ///
    /// `keywords` is a space-separated list of terms the section covers but
    /// does not have in its label ("pin" → Security, "api key" → Credentials).
    /// It backs the nav filter box: 16 sections spread over ~38 files are not
    /// discoverable by reading a nav list alone.
    struct NavButton {
        QPushButton* btn;
        QString source_key;
        QString keywords;
    };
    QList<NavButton> nav_buttons_;

    QLineEdit* nav_filter_ = nullptr;
    /// Show only nav entries matching `text` (label or keywords). Scope
    /// headers are hidden while a filter is active — with a partial list they
    /// no longer describe what sits under them.
    void apply_nav_filter(const QString& text);
    QList<QLabel*> scope_headers_; // entries align with scope_header_keys_
    QList<QString> scope_header_keys_;

    /// Factories for each section index. Used by the language-change rebuild
    /// path so we can recreate widgets without hardcoding the type list twice.
    QList<std::function<QWidget*()>> section_factories_;

    // ── MCP-driven UI sync ────────────────────────────────────────────────────
    QList<EventBus::HandlerId> mcp_event_subs_;
    void subscribe_mcp_events();
    void unsubscribe_mcp_events();
    void reload_visible_section(); // re-shows current section to retrigger its showEvent
};

} // namespace fincept::screens