crossdesk/libs/terminal/include/terminal_renderer.h

/*
 * @Author: DI JUNKUN
 * @Date: 2026-10-30
 * Copyright (c) 2026 by DI JUNKUN, All Rights Reserved.
 */

#ifndef _TERMINAL_RENDERER_H_
#define _TERMINAL_RENDERER_H_

#include <controller_session.h>
namespace crossdesk::terminal {
enum class AnsiDetail { Half, Quadrant };
struct Viewport {
  int columns = 80, rows = 23;
  double cell_aspect = .5;
  bool utf8 = true;
  int colors = 24;
  AnsiDetail detail = AnsiDetail::Half;
  double zoom = 1, center_x = .5, center_y = .5;
  int pixel_width = 0, pixel_height = 0;
  bool native = false, pixel_mode = false;
  int row_offset = 0; // Terminal rows reserved above the video area.
};
// Keep reported cell geometry across queries; never combine partial replies
// from different query cycles. Pixel/cell window sizes use the full text area.
class TerminalMetrics {
public:
  void BeginQuery();
  void Report(const std::string &sequence);
  void Apply(Viewport &) const;
  bool Known() const { return cell_width_ > 0; }

private:
  bool SetCellSize(double width, double height);
  double cell_width_ = 0, cell_height_ = 0;
  int pixel_width_ = 0, pixel_height_ = 0, columns_ = 0, rows_ = 0;
  bool queried_ = false, direct_reply_ = false;
};
inline constexpr char kTerminalSizeQuery[] = "\033[16t\033[14t\033[18t";
struct Rect {
  int x, y, width, height;
};
struct Cell {
  uint32_t top = 0, bottom = 0;
  uint32_t glyph = 0x2580;
  bool operator==(const Cell &other) const {
    return top == other.top && bottom == other.bottom && glyph == other.glyph;
  }
};
struct Grid {
  Viewport viewport;
  Rect content{};
  std::vector<Cell> cells;
  Rect source{};
  unsigned source_width = 0, source_height = 0;
  int samples_x = 1, samples_y = 2;
};
Rect Fit(int width, int height, int columns, int pixel_rows,
         double pixel_aspect = 1);
Grid Layout(const DecodedFrame &, Viewport);
Grid Convert(const DecodedFrame &, Viewport);
std::optional<std::pair<float, float>> MapPointer(const Grid &, int column,
                                                  int row);
std::vector<std::string> Lines(const Grid &);
std::string Difference(const Grid &, const std::optional<Grid> &previous);
struct PixelFrame {
  int width = 0, height = 0;
  std::vector<uint8_t> rgb;
};
PixelFrame KittyPixels(const DecodedFrame &, const Viewport &);
std::string KittySharedUpload(const std::string &name, int width, int height,
                              bool alternate_buffer, bool query = false);
std::string KittyPresent(const Viewport &, bool alternate_buffer);
struct KittyAck {
  uint32_t image_id = 0;
  bool ok = false;
};
std::optional<KittyAck> ParseKittyAck(const std::string &);
// Toggle alternate_buffer only after the previous output has been written in
// full. Upload to the other image ID before replacing the visible placement.
std::string Kitty(const DecodedFrame &, const Viewport &,
                  bool alternate_buffer = false);
inline constexpr char kKittyQuery[] =
    "\033_Gi=31,s=1,v=1,a=q,t=d,f=24;AAAA\033\\";
inline constexpr char kKittyDelete[] =
    "\033_Ga=d,d=I,i=31,q=2\033\\\033_Ga=d,d=I,i=32,q=2\033\\";
bool KittyReply(const std::string &response);
struct StatusBar {
  std::string progress, compact_progress, error, view, network, fps;
  bool control = false, command_mode = false;
};
// Three padded ASCII rows. Shortcuts are compacted as whole groups to fit.
std::vector<std::string> StatusLines(const StatusBar &, int columns);
// Incremental parser: protocol replies and unknown escapes are consumed
// locally. Key taps always release immediately; paste uses the UTF-8 text
// protocol. In command_mode, control records the mode to restore while the
// session's remote input is suspended until the user explicitly leaves the mode.
class Input {
public:
  void Feed(const std::string &bytes, ControllerSession &, const Grid *grid);
  bool exit = false, control = false, native = false, command_mode = false;
  std::string error;
  double zoom = 1, center_x = .5, center_y = .5;
  uint64_t view_revision = 0;
  uint64_t mouse_reports = 0;
  uint64_t mouse_legacy_reports = 0, mouse_forwarded = 0;
  uint64_t mouse_send_failures = 0;
  TerminalMetrics terminal_metrics;
  std::optional<KittyAck> kitty_ack;

private:
  std::string pending_;
  std::chrono::steady_clock::time_point last_input_{};
  bool pasting_ = false;
  unsigned mouse_buttons_ = 0;
  float pointer_x_ = .5f, pointer_y_ = .5f;
  void Tap(ControllerSession &, int key, int modifier = 0);
  bool LocalKey(int key, ControllerSession &, const Grid *);
  void Navigate(char key, const Grid *);
  void Mouse(int button, int x, int y, bool release, ControllerSession &,
             const Grid *);
};
} // namespace crossdesk::terminal

#endif