#pragma once

#include <QtCore>
#include <functional>
#include <lua.hpp>

#include "AsyncEventLoop.hpp"
#include "lua.h"
#include "utils.hpp"
#include "widgets/WebViewStack.hpp"

#ifndef PROJECT_LUA_PATH
#define PROJECT_LUA_PATH ""
#endif

#define preserve_top(STATE, BODY)                                                                  \
  {                                                                                                \
    const int __top = lua_gettop(STATE);                                                           \
    BODY;                                                                                          \
    lua_settop(STATE, __top);                                                                      \
  };

class LuaRuntime : public QObject {
  Q_OBJECT

  const char *uv_global_name = "uv";
  const char *internals_global_name = "__internals";

public:
  static LuaRuntime &instance() {
    static LuaRuntime runtime;
    return runtime;
  }

  void evaluate(const QString &code);
  void load_file_sync(const QString &path);

  void stop_event_loop();
  void start_event_loop();
  DELEGATE(event_loop, queue_task, queue_task)

  QVariant get_lua_value(int idx, QVariant default_value = 0);
  DEFINE_GETTER(get_state, state)

signals:
  void evaluation_completed(QVariant value);
  void evaluation_failed(QString value);

  void history_back_requested(WebViewId webview_id, qsizetype history_index);
  void history_forward_requested(WebViewId webview_id, qsizetype history_index);
  void keymap_added(QString mode, QString keyseq, std::function<void()>);
  void url_opened(QString url, OpenType open_type, WebViewId webview_id);
  void webview_closed(WebViewId webview_id);
  void webview_selected(WebViewId webview_id);
  void config_updated(const QString &key, const QVariant &value);

protected:
  LuaRuntime();
  ~LuaRuntime() override;
  void init_web_lib();

  // Lua api
  static int lua_history_back(lua_State *state);
  static int lua_history_forward(lua_State *state);
  static int lua_event_register(lua_State *state);
  static int lua_keymap_set(lua_State *state);
  static int lua_open_url(lua_State *state);
  static int lua_view_close(lua_State *state);
  static int lua_view_create(lua_State *state);
  static int lua_view_current(lua_State *state);
  static int lua_view_list(lua_State *state);
  static int lua_view_select(lua_State *state);
  static int lua_config_set(lua_State *state);
  static int lua_config_get(lua_State *state);

private:
  lua_State *state;
  AsyncEventLoop *event_loop = nullptr;

  // TEMP
public:
  static void inspect_lua_stack(lua_State *state) {
    int top = lua_gettop(state);
    qDebug() << "--- Lua Stack (top: " << top << ") ---\n";

    for (int i = 1; i <= top; i++) {
      int type = lua_type(state, i);
      qDebug() << "  " << i << ": " << lua_typename(state, type);
    }

    qDebug() << "---------------------------\n";
    lua_settop(state, top);
  }

  static std::vector<QString> lua_tostringlist(lua_State *state) {
    std::vector<QString> values;
    if (!lua_istable(state, -1))
      return values;

    lua_pushnil(state); // First key for lua_next()
    while (lua_next(state, -2) != 0) {
      if (lua_isstring(state, -1))
        values.emplace_back(lua_tostring(state, -1));
      lua_pop(state, 1);
    }
    lua_pop(state, 1);

    return values;
  }
};