#define FSM_DEBUG 1
#include "event_router.hpp"
#include "dbc.hpp"
#include "events.hpp"

namespace gui {
  namespace routing {
    using enum Event;
    using enum State;

    gui::Event Router::process_event(std::optional<sf::Event> ev) {
      $next_event = gui::Event::TICK;

      if(ev->is<sf::Event::Closed>()) {
        return gui::Event::QUIT;
      }

      if(const auto* mouse = ev->getIf<sf::Event::MouseButtonPressed>()) {
        if(mouse->button == sf::Mouse::Button::Left) {
           position = mouse->position;
           event(MOUSE_DOWN);
        }
      } else if(const auto* mouse = ev->getIf<sf::Event::MouseButtonReleased>()) {
        if(mouse->button == sf::Mouse::Button::Left) {
           position = mouse->position;
           event(MOUSE_UP);
        }
      } else if(const auto* mouse = ev->getIf<sf::Event::MouseMoved>()) {
        position = mouse->position;
        event(MOUSE_MOVE);
      }

      if(const auto* key = ev->getIf<sf::Event::KeyPressed>()) {
        scancode = key->scancode;
        event(KEY_PRESS);
      }

      return $next_event;
    }

    void Router::event(Event ev) {
      switch($state) {
        FSM_STATE(State, START, ev);
        FSM_STATE(State, IDLE, ev);
        FSM_STATE(State, MOUSE_ACTIVE, ev);
        FSM_STATE(State, MOUSE_MOVING, ev);
      }
    }

    void Router::START(Event ) {
      state(State::IDLE);
    }

    void Router::IDLE(Event ev) {
      switch(ev) {
        case MOUSE_DOWN:
          set_event(gui::Event::TICK);
          state(State::MOUSE_ACTIVE);
          break;
        case MOUSE_UP:
          dbc::log("mouse up in IDLE");
          break;
        case MOUSE_MOVE:
          dbc::log("mouse move, send moved event");
          break;
        case KEY_PRESS:
          dbc::log("key pressed");
          break;
        default:
          dbc::sentinel("invalid event");
      }
    }

    void Router::MOUSE_ACTIVE(Event ev) {
      switch(ev) {
        case MOUSE_DOWN:
          dbc::log("mouse down in MOUSE_ACTIVE");
          break;
        case MOUSE_UP:
          dbc::log("mouse up, send click event");
          state(State::IDLE);
          break;
        case MOUSE_MOVE:
          state(State::MOUSE_MOVING);
          break;
        case KEY_PRESS:
          dbc::log("send the key but cancel");
          state(State::IDLE);
          break;
        default:
          dbc::sentinel("invalid event");
      }
    }

    void Router::MOUSE_MOVING(Event ev) {
      switch(ev) {
        case MOUSE_DOWN:
          dbc::log("mouse down in MOUSE_MOVING state");
          break;
        case MOUSE_UP:
          dbc::log("mouse up, send drop event");
          state(State::IDLE);
          break;
        case MOUSE_MOVE:
          dbc::log("mouse move, send drag event");
          break;
        case KEY_PRESS:
          dbc::log("send the key but cancel");
          state(State::IDLE);
          break;
        default:
          dbc::sentinel("invalid event");
      }
    }
  }
}