path: root/extension/src/openvic-extension/classes/GUITextLabel.cpp

#include "GUITextLabel.hpp"

#include <godot_cpp/classes/style_box_texture.hpp>
#include <godot_cpp/variant/utility_functions.hpp>

#include "openvic-extension/singletons/AssetManager.hpp"
#include "openvic-extension/utility/ClassBindings.hpp"
#include "openvic-extension/utility/Utilities.hpp"

using namespace OpenVic;
using namespace godot;
using namespace OpenVic::Utilities::literals;

void GUITextLabel::_bind_methods() {
   OV_BIND_METHOD(GUITextLabel::clear);

   OV_BIND_METHOD(GUITextLabel::get_text);
   OV_BIND_METHOD(GUITextLabel::set_text, { "new_text" });

   OV_BIND_METHOD(GUITextLabel::get_substitution_dict);
   OV_BIND_METHOD(GUITextLabel::add_substitution, { "key", "value" });
   OV_BIND_METHOD(GUITextLabel::set_substitution_dict, { "new_substitution_dict" });
   OV_BIND_METHOD(GUITextLabel::clear_substitutions);

   OV_BIND_METHOD(GUITextLabel::get_alignment);
   OV_BIND_METHOD(GUITextLabel::get_gui_text_name);

   ADD_PROPERTY(PropertyInfo(Variant::STRING, "text"), "set_text", "get_text");
   ADD_PROPERTY(PropertyInfo(Variant::DICTIONARY, "substitution_dict"), "set_substitution_dict", "get_substitution_dict");
}

void GUITextLabel::_notification(int what) {
   switch (what) {
   case NOTIFICATION_RESIZED:
   case NOTIFICATION_TRANSLATION_CHANGED: {
      _queue_line_update();
   } break;
   case NOTIFICATION_DRAW: {
      const RID ci = get_canvas_item();
      const Size2 size = get_size();

      if (background.is_valid()) {
         draw_style_box(background, Rect2 { {}, size });
      }

      if (font.is_null()) {
         return;
      }

      const Vector2 content_max_size = get_content_max_size();

      // Starting offset needed
      static const Vector2 base_offset { 1.0_real, -1.0_real };
      const Vector2 offset = base_offset + border_size;
      Vector2 position = offset;

      for (line_t const& line : lines) {
         position.x = offset.x;
         switch (alignment) {
         case HORIZONTAL_ALIGNMENT_CENTER: {
            position.x += (content_max_size.width - line.width + 1.0_real) / 2.0_real;
         } break;
         case HORIZONTAL_ALIGNMENT_RIGHT: {
            position.x += content_max_size.width - line.width;
         } break;
         case HORIZONTAL_ALIGNMENT_LEFT:
         default:
            break;
         }

         position.y += font->get_ascent(font->get_fixed_size());

         for (segment_t const& segment : line.segments) {
            string_segment_t const* string_segment = std::get_if<string_segment_t>(&segment);

            if (string_segment == nullptr) {
               if (currency_texture.is_valid()) {
                  currency_texture->draw(
                     ci, position - Vector2 {
                        1.0_real, static_cast<real_t>(currency_texture->get_height()) * 0.75_real
                     }
                  );
                  position.x += currency_texture->get_width();
               }
            } else {
               font->draw_string(
                  ci, position, string_segment->text, HORIZONTAL_ALIGNMENT_LEFT, -1, font->get_fixed_size(),
                  string_segment->colour
               );
               position.x += string_segment->width;
            }
         }

         position.y += font->get_descent(font->get_fixed_size());
      }

   } break;
   }
}

GUITextLabel::GUITextLabel()
  : gui_text { nullptr }, alignment { HORIZONTAL_ALIGNMENT_LEFT }, colour_codes { nullptr }, line_update_queued { false } {}

void GUITextLabel::clear() {
   gui_text = nullptr;

   text = String {};
   substitution_dict.clear();
   alignment = HORIZONTAL_ALIGNMENT_LEFT;
   border_size = {};

   _update_font(nullptr);

   background.unref();
   lines.clear();

   line_update_queued = false;

   queue_redraw();
}

Error GUITextLabel::set_gui_text(GUI::Text const* new_gui_text, GFX::Font::colour_codes_t const* override_colour_codes) {
   if (gui_text == new_gui_text) {
      return OK;
   }

   if (new_gui_text == nullptr) {
      clear();
      return OK;
   }

   gui_text = new_gui_text;

   text = Utilities::std_to_godot_string(gui_text->get_text());

   using enum GUI::AlignedElement::format_t;
   static const ordered_map<GUI::AlignedElement::format_t, HorizontalAlignment> format_map {
      { left, HORIZONTAL_ALIGNMENT_LEFT },
      { centre, HORIZONTAL_ALIGNMENT_CENTER },
      { right, HORIZONTAL_ALIGNMENT_RIGHT }
   };
   const decltype(format_map)::const_iterator it = format_map.find(gui_text->get_format());
   alignment = it != format_map.end() ? it->second : HORIZONTAL_ALIGNMENT_LEFT;

   set_custom_minimum_size(Utilities::to_godot_fvec2(gui_text->get_max_size()));
   border_size = Utilities::to_godot_fvec2(gui_text->get_border_size());

   _queue_line_update();

   Error err = _update_font(override_colour_codes);

   background.unref();

   if (!gui_text->get_texture_file().empty()) {
      AssetManager* asset_manager = AssetManager::get_singleton();
      ERR_FAIL_NULL_V(asset_manager, FAILED);

      const StringName texture_path = Utilities::std_to_godot_string(gui_text->get_texture_file());
      Ref<ImageTexture> texture = asset_manager->get_texture(texture_path);
      ERR_FAIL_NULL_V_MSG(
         texture, FAILED, vformat("Failed to load texture \"%s\" for GUITextLabel %s", texture_path, get_name())
      );

      background.instantiate();
      ERR_FAIL_NULL_V(background, FAILED);
      background->set_texture(texture);

      background->set_texture_margin(SIDE_LEFT, border_size.x);
      background->set_texture_margin(SIDE_RIGHT, border_size.x);
      background->set_texture_margin(SIDE_TOP, border_size.y);
      background->set_texture_margin(SIDE_BOTTOM, border_size.y);
   }

   return err;
}

String GUITextLabel::get_gui_text_name() const {
   return gui_text != nullptr ? Utilities::std_to_godot_string(gui_text->get_name()) : String {};
}

void GUITextLabel::set_text(String const& new_text) {
   if (text != new_text) {
      text = new_text;
      _queue_line_update();
   }
}

void GUITextLabel::add_substitution(String const& key, String const& value) {
   Variant& existing_value = substitution_dict[key];
   if (existing_value != value) {
      existing_value = value;
      _queue_line_update();
   }
}

void GUITextLabel::set_substitution_dict(Dictionary const& new_substitution_dict) {
   substitution_dict = new_substitution_dict;
   _queue_line_update();
}

void GUITextLabel::clear_substitutions() {
   if (!substitution_dict.is_empty()) {
      substitution_dict.clear();
      _queue_line_update();
   }
}

Vector2 GUITextLabel::get_content_max_size() const {
   return get_size() - 2 * border_size;
}

Error GUITextLabel::_update_font(GFX::Font::colour_codes_t const* override_colour_codes) {
   if (gui_text == nullptr || gui_text->get_font() == nullptr) {
      font.unref();
      default_colour = {};
      colour_codes = nullptr;
      currency_texture.unref();

      return OK;
   }

   default_colour = Utilities::to_godot_color(gui_text->get_font()->get_colour());
   colour_codes = override_colour_codes != nullptr ? override_colour_codes : &gui_text->get_font()->get_colour_codes();

   AssetManager* asset_manager = AssetManager::get_singleton();
   ERR_FAIL_NULL_V_MSG(asset_manager, FAILED, "Failed to get AssetManager singleton for GUITextLabel");

   const StringName font_file = Utilities::std_to_godot_string(gui_text->get_font()->get_fontname());
   font = asset_manager->get_font(font_file);
   ERR_FAIL_NULL_V_MSG(font, FAILED, vformat("Failed to load font \"%s\" for GUITextLabel", font_file));

   currency_texture = asset_manager->get_currency_texture(font->get_fixed_size());
   ERR_FAIL_NULL_V(currency_texture, FAILED);

   return OK;
}

real_t GUITextLabel::get_string_width(String const& string) const {
   return font->get_string_size(string, HORIZONTAL_ALIGNMENT_LEFT, -1, font->get_fixed_size()).x;
}

real_t GUITextLabel::get_segment_width(segment_t const& segment) const {
   if (string_segment_t const* string_segment = std::get_if<string_segment_t>(&segment)) {
      return string_segment->width;
   } else if (currency_texture.is_valid()) {
      return currency_texture->get_width();
   } else {
      return 0.0_real;
   }
}

void GUITextLabel::_queue_line_update() {
   if (!line_update_queued) {
      line_update_queued = true;

      callable_mp(this, &GUITextLabel::_update_lines).call_deferred();
   }
}

void GUITextLabel::_update_lines() {
   line_update_queued = false;
   lines.clear();

   if (text.is_empty() || font.is_null()) {
      queue_redraw();
      return;
   }

   String const& base_text = is_auto_translating() ? tr(text) : text;

   String const& substituted_text = generate_substituted_text(base_text);

   auto const& [display_text, colour_instructions] = generate_display_text_and_colour_instructions(substituted_text);

   std::vector<line_t> unwrapped_lines = generate_lines_and_segments(display_text, colour_instructions);

   lines = wrap_lines(unwrapped_lines);

   // TODO - trim and add ellipsis if necessary

   queue_redraw();
}

String GUITextLabel::generate_substituted_text(String const& base_text) const {
   static const String SUBSTITUTION_MARKER = String::chr(0x24); // $

   String result;
   int64_t start_pos = 0;
   int64_t marker_start_pos;

   while ((marker_start_pos = base_text.find(SUBSTITUTION_MARKER, start_pos)) != -1) {
      result += base_text.substr(start_pos, marker_start_pos - start_pos);

      int64_t marker_end_pos = base_text.find(SUBSTITUTION_MARKER, marker_start_pos + SUBSTITUTION_MARKER.length());
      if (marker_end_pos == -1) {
         return result;
      }

      String key = base_text.substr(
         marker_start_pos + SUBSTITUTION_MARKER.length(), marker_end_pos - marker_start_pos - SUBSTITUTION_MARKER.length()
      );
      String value = substitution_dict.get(key, String {});

      result += value;

      start_pos = marker_end_pos + SUBSTITUTION_MARKER.length();
   }

   result += base_text.substr(start_pos);

   return result;
}

std::pair<String, GUITextLabel::colour_instructions_t> GUITextLabel::generate_display_text_and_colour_instructions(
   String const& substituted_text
) const {
   static const String COLOUR_MARKER = String::chr(0xA7); // §

   String result;
   colour_instructions_t colour_instructions;
   int64_t start_pos = 0;
   int64_t marker_pos;

   while ((marker_pos = substituted_text.find(COLOUR_MARKER, start_pos)) != -1) {
      result += substituted_text.substr(start_pos, marker_pos - start_pos);

      if (marker_pos + COLOUR_MARKER.length() < substituted_text.length()) {
         const char32_t colour_code = substituted_text[marker_pos + COLOUR_MARKER.length()];

         // Check that the colour code can be safely cast to a char
         if (colour_code >> sizeof(char) * CHAR_BIT == 0) {
            colour_instructions.emplace_back(result.length(), static_cast<char>(colour_code));
         }

         start_pos = marker_pos + COLOUR_MARKER.length() + 1;
      } else {
         return { std::move(result), std::move(colour_instructions) };
      }
   }

   result += substituted_text.substr(start_pos);

   return { std::move(result), std::move(colour_instructions) };
}

std::vector<GUITextLabel::line_t> GUITextLabel::generate_lines_and_segments(
   String const& display_text, colour_instructions_t const& colour_instructions
) const {
   static constexpr char RESET_COLOUR_CODE = '!';

   std::vector<line_t> unwrapped_lines;
   colour_instructions_t::const_iterator colour_it = colour_instructions.begin();
   Color current_colour = default_colour;
   int64_t section_start = 0;

   unwrapped_lines.emplace_back();

   for (int64_t idx = 0; idx < display_text.length(); ++idx) {
      if (colour_it != colour_instructions.end() && idx == colour_it->first) {
         Color new_colour = current_colour;
         if (colour_it->second == RESET_COLOUR_CODE) {
            new_colour = default_colour;
         } else {
            const GFX::Font::colour_codes_t::const_iterator it = colour_codes->find(colour_it->second);
            if (it != colour_codes->end()) {
               new_colour = Utilities::to_godot_color(it->second);
            }
         }
         ++colour_it;

         if (current_colour != new_colour) {
            if (section_start < idx) {
               separate_lines(
                  display_text.substr(section_start, idx - section_start), current_colour, unwrapped_lines
               );
               section_start = idx;
            }
            current_colour = new_colour;
         }
      }
   }

   if (section_start < display_text.length()) {
      separate_lines(display_text.substr(section_start), current_colour, unwrapped_lines);
   }

   return unwrapped_lines;
}

void GUITextLabel::separate_lines(
   String const& string, Color const& colour, std::vector<line_t>& unwrapped_lines
) const {
   static const String NEWLINE_MARKER = "\n";

   int64_t start_pos = 0;
   int64_t newline_pos;

   while ((newline_pos = string.find(NEWLINE_MARKER, start_pos)) != -1) {
      if (start_pos < newline_pos) {
         separate_currency_segments(string.substr(start_pos, newline_pos - start_pos), colour, unwrapped_lines.back());
      }

      unwrapped_lines.emplace_back();

      start_pos = newline_pos + NEWLINE_MARKER.length();
   }

   if (start_pos < string.length()) {
      separate_currency_segments(string.substr(start_pos), colour, unwrapped_lines.back());
   }
}

void GUITextLabel::separate_currency_segments(
   String const& string, Color const& colour, line_t& line
) const {
   static const String CURRENCY_MARKER = String::chr(0xA4); // ¤

   const auto push_string_segment = [this, &string, &colour, &line](int64_t start, int64_t end) -> void {
      String substring = string.substr(start, end - start);
      const real_t width = get_string_width(substring);
      line.segments.emplace_back(string_segment_t { std::move(substring), colour, width });
      line.width += width;
   };

   int64_t start_pos = 0;
   int64_t marker_pos;

   const real_t currency_width = currency_texture.is_valid() ? currency_texture->get_width() : 0.0_real;

   while ((marker_pos = string.find(CURRENCY_MARKER, start_pos)) != -1) {
      if (start_pos < marker_pos) {
         push_string_segment(start_pos, marker_pos);
      }

      line.segments.push_back(currency_segment_t {});
      line.width += currency_width;

      start_pos = marker_pos + CURRENCY_MARKER.length();
   }

   if (start_pos < string.length()) {
      push_string_segment(start_pos, string.length());
   }
}

std::vector<GUITextLabel::line_t> GUITextLabel::wrap_lines(std::vector<line_t>& unwrapped_lines) const {
   std::vector<line_t> wrapped_lines;

   const Size2 size = get_content_max_size();

   for (line_t& line : unwrapped_lines) {
      if (line.width <= size.x) {
         wrapped_lines.push_back(std::move(line));
      } else {
         line_t* current_line = &wrapped_lines.emplace_back();

         for (segment_t& segment : line.segments) {
            const real_t segment_width = get_segment_width(segment);

            if (current_line->width + segment_width <= size.x) {
               // Segement on current line
               current_line->segments.emplace_back(std::move(segment));
               current_line->width += segment_width;
            } else if (string_segment_t const* string_segment = std::get_if<string_segment_t>(&segment)) {
               // String segement wrapped onto new line
               static const String SPACE_MARKER = " ";

               String const& string = string_segment->text;

               int64_t start_pos = 0;

               while (start_pos < string.length()) {
                  String whole_segment_string = string.substr(start_pos);
                  real_t whole_segment_width = get_string_width(whole_segment_string);

                  if (current_line->width + whole_segment_width > size.x) {
                     String new_segment_string;
                     real_t new_segment_width = 0.0_real;

                     int64_t last_marker_pos = 0;
                     int64_t marker_pos;

                     while ((marker_pos = whole_segment_string.find(SPACE_MARKER, last_marker_pos)) != -1) {
                        String substring = whole_segment_string.substr(0, marker_pos);
                        const real_t width = get_string_width(substring);
                        if (current_line->width + width <= size.x) {
                           new_segment_string = std::move(substring);
                           new_segment_width = width;
                           last_marker_pos = marker_pos + SPACE_MARKER.length();
                        } else {
                           break;
                        }
                     }

                     if (last_marker_pos != 0 || !current_line->segments.empty()) {
                        if (!new_segment_string.is_empty()) {
                           current_line->segments.emplace_back(string_segment_t {
                              std::move(new_segment_string), string_segment->colour, new_segment_width
                           });
                           current_line->width += new_segment_width;
                        }

                        current_line = &wrapped_lines.emplace_back();

                        start_pos += last_marker_pos;

                        continue;
                     }
                  }
                  current_line->segments.emplace_back(string_segment_t {
                     std::move(whole_segment_string), string_segment->colour, whole_segment_width
                  });
                  current_line->width += whole_segment_width;
                  break;
               }

            } else {
               // Currency segement on new line
               line_t* current_line = &wrapped_lines.emplace_back();
               current_line->segments.push_back(std::move(segment));
               current_line->width = segment_width;
            }
         }
      }
   }

   if (wrapped_lines.size() > 1 && wrapped_lines.size() * font->get_height(font->get_fixed_size()) > size.y) {
      do {
         wrapped_lines.pop_back();
      } while (wrapped_lines.size() > 1 && wrapped_lines.size() * font->get_height(font->get_fixed_size()) > size.y);

      static const String ELLIPSIS = "...";
      const real_t ellipsis_width = get_string_width(ELLIPSIS);

      line_t& last_line = wrapped_lines.back();
      Color last_colour = default_colour;

      while (last_line.segments.size() > 0 && last_line.width + ellipsis_width > size.x) {
         if (string_segment_t* string_segment = std::get_if<string_segment_t>(&last_line.segments.back())) {
            last_colour = string_segment->colour;

            String& last_string = string_segment->text;
            if (last_string.length() > 1) {
               last_string = last_string.substr(0, last_string.length() - 1);

               last_line.width -= string_segment->width;
               string_segment->width = get_string_width(last_string);
               last_line.width += string_segment->width;
            } else {
               last_line.width -= string_segment->width;
               last_line.segments.pop_back();
            }
         } else {
            last_line.width -= currency_texture->get_width();
            last_line.segments.pop_back();
         }
      }

      last_line.segments.push_back(string_segment_t { ELLIPSIS, last_colour, ellipsis_width });
      last_line.width += ellipsis_width;
   }

   return wrapped_lines;
}