ca-ascii.H

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/*
                          Aleph_w
 
  Data structures & Algorithms
  version 2.0.0b
  https://github.com/lrleon/Aleph-w
 
  This file is part of Aleph-w library
 
  Copyright (c) 2002-2026 Leandro Rabindranath Leon
 
  Permission is hereby granted, free of charge, to any person obtaining a copy
  of this software and associated documentation files (the "Software"), to deal
  in the Software without restriction, including without limitation the rights
  to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  copies of the Software, and to permit persons to whom the Software is
  furnished to do so, subject to the following conditions:
 
  The above copyright notice and this permission notice shall be included in all
  copies or substantial portions of the Software.
 
  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  SOFTWARE.
*/
 
#ifndef CA_ASCII_H
#define CA_ASCII_H
 
#include <concepts>
#include <cstddef>
#include <ostream>
#include <sstream>
#include <string>
#include <utility>
 
#include <ah-errors.H>
 
#include <ca-io.H>
#include <tpl_ca_concepts.H>
 
namespace Aleph {
namespace CA {
 
struct Ascii_Render_Options
{
  bool include_border = false;           
  bool include_trailing_newline = true;  
  std::string line_prefix;               
};
 
template <typename State>
struct Binary_ASCII_Palette
{
  State dead{};                   
  std::string dead_glyph = ".";   
  std::string alive_glyph = "#";  
 
  [[nodiscard]] std::string operator()(const State &value) const
  {
    return value == dead ? dead_glyph : alive_glyph;
  }
 
  [[nodiscard]] std::size_t glyph_width() const noexcept
  {
    return dead_glyph.size() > alive_glyph.size() ? dead_glyph.size() : alive_glyph.size();
  }
};
 
template <typename State>
struct Binary_ANSI24_Palette
{
  State dead{};                      
  RGB8 dead_colour{20, 24, 28};      
  RGB8 alive_colour{230, 245, 255};  
  std::string glyph = "  ";          
 
  [[nodiscard]] std::string operator()(const State &value) const
  {
    const RGB8 c = value == dead ? dead_colour : alive_colour;
    std::ostringstream out;
    out << "\033[48;2;" << static_cast<unsigned>(c.r) << ';' << static_cast<unsigned>(c.g) << ';'
        << static_cast<unsigned>(c.b) << 'm' << glyph << "\033[0m";
    return out.str();
  }
 
  [[nodiscard]] std::size_t glyph_width() const noexcept
  {
    return glyph.size();
  }
};
 
template <typename Lattice, typename Palette>
inline void render_ascii(std::ostream &out,
                         const Lattice &frame,
                         Palette &&palette,
                         const Ascii_Render_Options &opts = {})
  requires requires(Palette &&p, const typename Lattice::state_type &v) {
    { p(v) } -> std::convertible_to<std::string>;
  }
{
  static_assert(LatticeLike<Lattice>, "render_ascii requires a LatticeLike frame");
  static_assert(Lattice::rank == 2, "render_ascii requires a rank-2 frame");
  using coord_t = typename Lattice::coord_type;
 
  // Visible width of one rendered cell, in terminal columns. Palettes
  // may opt in by exposing a `glyph_width()` method (e.g.
  // `Binary_ANSI24_Palette` whose two-space glyph occupies 2 columns).
  // Default to 1 for legacy palettes.
  std::size_t glyph_w = 1;
  if constexpr (requires { palette.glyph_width(); })
    glyph_w = palette.glyph_width();
  if (glyph_w == 0)
    glyph_w = 1;
 
  auto write_border = [&](const bool emit_newline)
  {
    out << opts.line_prefix << '+';
    const ca_size_t dashes = frame.size(1) * static_cast<ca_size_t>(glyph_w);
    for (ca_size_t c = 0; c < dashes; ++c)
      out << '-';
    out << '+';
    if (emit_newline)
      out << '\n';
  };
 
  if (opts.include_border)
    write_border(true);
 
  for (ca_size_t r = 0; r < frame.size(0); ++r)
    {
      out << opts.line_prefix;
      if (opts.include_border)
        out << '|';
      for (ca_size_t c = 0; c < frame.size(1); ++c)
        out << palette(frame.at(coord_t{static_cast<ca_index_t>(r), static_cast<ca_index_t>(c)}));
      if (opts.include_border)
        out << '|';
      // Always terminate intermediate rows; the trailing newline of
      // the last row is governed by `include_trailing_newline`.
      // When a bottom border follows, the row separator is required
      // to keep the border on its own line.
      if (r + 1 < frame.size(0) or opts.include_border or opts.include_trailing_newline)
        out << '\n';
    }
 
  if (opts.include_border)
    write_border(opts.include_trailing_newline);
 
  ah_runtime_error_if(not out) << "render_ascii: output stream failed";
}
 
template <typename Lattice, typename Palette>
[[nodiscard]] inline std::string render_ascii_string(const Lattice &frame,
                                                     Palette &&palette,
                                                     const Ascii_Render_Options &opts = {})
  requires requires(Palette &&p, const typename Lattice::state_type &v) {
    { p(v) } -> std::convertible_to<std::string>;
  }
{
  std::ostringstream out;
  render_ascii(out, frame, std::forward<Palette>(palette), opts);
  return out.str();
}
 
template <typename Lattice>
inline void render_ascii(std::ostream &out, const Lattice &frame, const Ascii_Render_Options &opts = {})
{
  render_ascii(out, frame, Binary_ASCII_Palette<typename Lattice::state_type>{}, opts);
}
 
template <typename Lattice>
[[nodiscard]] inline std::string render_ascii_string(const Lattice &frame,
                                                     const Ascii_Render_Options &opts = {})
{
  std::ostringstream out;
  render_ascii(out, frame, opts);
  return out.str();
}
 
template <typename Palette>
class Ascii_Frame_Sink
{
  std::ostream *out_ = nullptr;
  Palette palette_;
  Ascii_Render_Options opts_{};
  bool include_step_header_ = true;
 
public:
  Ascii_Frame_Sink(std::ostream &out,
                   Palette palette,
                   Ascii_Render_Options opts = {},
                   const bool include_step_header = true)
    : out_(&out), palette_(std::move(palette)), opts_(std::move(opts)),
      include_step_header_(include_step_header)
  {}
 
  template <typename Lattice>
  void accept(const std::size_t step, const Lattice &frame)
  {
    if (include_step_header_)
      *out_ << "# step " << step << '\n';
    render_ascii(*out_, frame, palette_, opts_);
  }
 
  void flush()
  {
    out_->flush();
    ah_runtime_error_if(not *out_) << "Ascii_Frame_Sink::flush: output stream failed";
  }
};
 
template <typename Palette>
Ascii_Frame_Sink(std::ostream &, Palette, Ascii_Render_Options = {}, bool = true)
  -> Ascii_Frame_Sink<Palette>;
 
}  // namespace CA
}  // namespace Aleph
 
#endif  // CA_ASCII_H