#pragma once
#include "UiTypes.h"
#include "Config.h"

// Nextion serial HMI driver. No Nextion library - the protocol is small:
//
//  Nextion -> remote: custom frames the HMI's touch events send with printh:
//      '#' <len> <cmd> [value]        e.g. printh 23 01 41   (ToggleArm)
//                                          printh 23 02 56 + prints hSpeed.val,1
//    Command bytes are listed in NEXTION.md and in NextionUI.cpp.
//    Native Nextion return frames (terminated FF FF FF) are also parsed so a
//    display reset (0x88 "ready") triggers a full redraw.
//
//  remote -> Nextion: plain instructions ("bArm.txt=\"ARMED\"" + FF FF FF).
//
// The remote is authoritative: buttons are plain buttons (not dual-state),
// they only send requests, and render() repaints whatever the remote state
// actually is. A Nextion reboot or a dropped byte self-heals on the next
// periodic full refresh.
class NextionUI {
public:
  void begin();
  bool poll(UiEvent& out);                 // call every loop; returns one decoded event at a time
  void render(const UiView& v, uint32_t now_ms);

private:
  enum class Rx : uint8_t { Idle, CustomLen, CustomBody, Native };
  Rx rx_ = Rx::Idle;
  uint8_t body_[4];
  uint8_t body_len_ = 0, body_got_ = 0;
  uint8_t native_first_ = 0, native_len_ = 0, ff_run_ = 0;

  UiView shown_;
  bool force_full_ = true;
  uint32_t last_full_ms_ = 0;
  uint32_t last_link_ms_ = 0;

  void cmd(const char* fmt, ...);
  void pushState(const UiView& v, bool full);
  void pushLink(const UiView& v);
  bool decodeCustom(UiEvent& out);
};