#include <FL/Fl.H>
#include <FL/Fl_Button.H>
#include <FL/Fl_Double_Window.H>
#include <FL/Fl_Input.H>
#include <FL/Fl_Text_Buffer.H>
#include <FL/Fl_Text_Editor.H>
#include <cstdlib>
#include <iostream>
#include <string>

using namespace std;

Fl_Double_Window *win;
Fl_Text_Editor *ted;
Fl_Button *buta;
Fl_Text_Buffer *buf;
Fl_Text_Buffer *style_buffer;

Fl_Text_Editor::Style_Table_Entry styles[] = {
    {FL_BLACK, FL_COURIER, 15}, // 'A'
    {FL_RED, FL_BOLD, 16}       // 'B'
};

void change_cback(int pos,                 // I - Position of update
                  int nInserted,           // I - Number of inserted chars
                  int nDeleted,            // I - Number of deleted chars
                  int nRestyled,           // I - Number of restyled chars
                  const char *deletedText, // I - Text that was deleted
                  void *cbArg) {

  if (nDeleted > 0)
    style_buffer->remove(pos, pos + nDeleted);

  if (nInserted > 0) {
    for (int i = 0; i < nInserted; i++) {
      style_buffer->insert(pos, "A");
    }
  }

  cout << "change_cb(" << pos << ',' << nInserted << ',' << nDeleted << ")"
       << " length(style_buffer) = " << style_buffer->length() << endl;
}

void style_unfinished_cb(int p, void *v) {
  // cout << "style_unfinished_cb(" << p << "," << v << ")" << endl;
}

void change_text(Fl_Widget *wid, void *data) {
  string s_char;
  int int_cnt = 0;
  int n_chars_selected = strlen(buf->selection_text());
  for (int i = 0; i < n_chars_selected; i++) {
    s_char += "B";
    int_cnt += i;
  }

  Fl_Text_Selection *ts = buf->primary_selection();
  cout << "Selection = (" << ts->start() << ',' << ts->end() << ')' << endl;

  int start_pos = ts->start();
  int end_pos = ts->start() + n_chars_selected; // should be: ts->end();

  if (n_chars_selected > 0)
    style_buffer->replace(start_pos, end_pos, s_char.c_str());

  cout << "change_text(" << start_pos << ',' << end_pos << ','
       << n_chars_selected << ")"
       << " length(style_buffer) = " << style_buffer->length() << endl;

  ted->redraw();
}

int main() {
  win = new Fl_Double_Window(800, 700, "Test_Window");
  ted = new Fl_Text_Editor(50, 50, 600, 500);
  buta = new Fl_Button(50, 600, 80, 40, "Bold");
  buf = new Fl_Text_Buffer();
  ted->buffer(buf);

  style_buffer = new Fl_Text_Buffer();

  ted->highlight_data(style_buffer, styles, 2, 'A', style_unfinished_cb, 0);

  buf->add_modify_callback(change_cback, ted);
  buta->callback(change_text);

  win->show();
  return (Fl::run()); // sets event loop
}