Example 6: A Text Editor

This chapter takes you through the design of a simple FLTK-based text editor. This is an example of how you can build a complex application out of just the widgets provided by FLTK.

The full source code is at the end of this document.

This chapter needs some work!

Determining the Goals of the Text Editor

Since this will be the first big project you'll be doing with FLTK, lets define what we want our text editor to do:

• Menubar/menus for all functions.
• Edit a single text file.
• Load from a file.
• Save to a file.
• Cut/copy/delete/paste functions.
• Search and replace functions.
• Keep track of when the file has been changed.

Designing the Main Window

Now that we've outlined the goals for our editor, we can begin with the design of our GUI. Obviously the first thing that we need is a window:

class EditorWindow : public fltk::Window {
  public:
    EditorWindow(int w, int h, const char* t);
    ~EditorWindow();

Variables

Our text editor window will need some variables to keep track of stuff. In addition we will use some global variables for stuff that is shared between all editor windows, such as the search string:

    fltk::Window          *replace_dlg;
    fltk::Input           *replace_find;
    fltk::Input           *replace_with;
    fltk::Button          *replace_all;
    fltk::ReturnButton   *replace_next;
    fltk::Button          *replace_cancel;

    fltk::TextEditor     *editor;
    char               search[256];
};

Menubars and Menus

In the constructor for EditorWindow, most of the work is in building the menubar that goes across the top. Menus are populated by "items", which are actually normal Widgets, each with a callback function to do the actual work. Here though we call the Menu::add() function, which is a convenience function for creating a large hierarchy of widgets:

EditorWindow::EditorWindow(int w, int h, const char* t) : fltk::Window(w, h, t) {
  replace_dlg = new fltk::Window(300, 105, "Replace");
  replace_dlg->begin();
    replace_find = new fltk::Input(80, 10, 210, 25, "Find:");
    replace_find->align(fltk::ALIGN_LEFT);

    replace_with = new fltk::Input(80, 40, 210, 25, "Replace:");
    replace_with->align(fltk::ALIGN_LEFT);

    replace_all = new fltk::Button(10, 70, 90, 25, "Replace All");
    replace_all->callback((fltk::Callback *)replall_cb, this);

    replace_next = new fltk::ReturnButton(105, 70, 120, 25, "Replace Next");
    replace_next->callback((fltk::Callback *)replace2_cb, this);

We'll define the callback functions later.

Editing the Text

To keep things simple our text editor will use the fltk::TextEditor widget to edit the text.

So that we can keep track of changes to the file, we also want to add a "changed" callback:

input->callback(changed_cb); input->when(fltk::WHEN_CHANGED);

Finally, we want to use a mono-spaced font like fltk::COURIER: input->textfont(fltk::COURIER);

The Replace Dialog

We can use the FLTK convenience functions for many of the editor's dialogs, however the replace dialog needs its own custom window. To keep things simple we will have a "find" string, a "replace" string, and "replace all", "replace next", and "cancel" buttons. The strings are just fltk::Input widgets, the "replace all" and "cancel" buttons are fltk::Button widgets, and the "replace next " button is a fltk::ReturnButton widget:

(code to generate replace dialog here)

Callbacks

Now that we've defined the GUI components of our editor, we need to define our callback functions.

This callback function will call input->copy() to copy the currently selected text to the clipboard:

void copy_cb(fltk::Widget*, void* v) {
  EditorWindow* e = (EditorWindow*)v;
  fltk::TextEditor::kf_copy(0, e->editor);
}

This callback function will call input->copy() to copy the currently selected text to the clipboard and then input->cut() to delete it:

void cut_cb(fltk::Widget*, void* v) {
  EditorWindow* e = (EditorWindow*)v;
  fltk::TextEditor::kf_cut(0, e->editor);
}

This callback function will call input->cut() to delete the selected text:

void delete_cb(fltk::Widget*, void*) {
  textbuf->remove_selection();
}

This callback function asks for a search string using the fltk::input() convenience function and then calls the find2_cb() function to find the string:

void find_cb(fltk::Widget* w, void* v) {
  EditorWindow* e = (EditorWindow*)v;
  const char *val;

  val = fltk::input("Search String:", e->search);
  if (val != NULL) {
    // User entered a string - go find it!
    strcpy(e->search, val);
    find2_cb(w, v);
  }
}

This function will find the next occurrence of the search string. If the search string is blank then we want to pop up the search dialog:

void find2_cb(fltk::Widget* w, void* v) {
  EditorWindow* e = (EditorWindow*)v;
  if (e->search[0] == '\0') {
    // Search string is blank; get a new one...
    find_cb(w, v);
    return;
  }

  int pos = e->editor->insert_position();
  int found = textbuf->search_forward(pos, e->search, &pos);
  if (found) {
    // Found a match; select and update the position...
    textbuf->select(pos, pos+strlen(e->search));
    e->editor->insert_position(pos+strlen(e->search));
    e->editor->show_insert_position();
  }
  else fltk::alert("No occurrences of \'%s\' found!", e->search);
}

This callback function will clear the input widget and current filename. It also calls the check_save() function to give the user the opportunity to save the current file first as needed:

void new_cb(fltk::Widget*, void*) {
  if (!check_save()) return;

  filename[0] = '\0';
  textbuf->select(0, textbuf->length());
  textbuf->remove_selection();
  changed = 0;
  textbuf->call_modify_callbacks();
}

This callback function will ask the user for a filename and then load the specified file into the input widget and current filename. It also calls the check_save() function to give the user the opportunity to save the current file first as needed:

void open_cb(fltk::Widget*, void*) {
  if (!check_save()) return;

  const char *newfile = fltk::file_chooser("Open File?", "*", filename);
  if (newfile != NULL) load_file(newfile, -1);
}

This callback function will send a fltk::PASTE message to the input widget using the fltk::paste() method:

void paste_cb(fltk::Widget*, void* v) {
  EditorWindow* e = (EditorWindow*)v;
  fltk::TextEditor::kf_paste(0, e->editor);
}

The quit callback will first see if the current file has been modified, and if so give the user a chance to save it. It then hides the main window:

void quit_cb(fltk::Widget*, void*) {
  if (changed && !check_save())
    return;

  exit(0);
}

The replace callback just shows the replace dialog:

void replace_cb(fltk::Widget*, void* v) {
  EditorWindow* e = (EditorWindow*)v;
  e->replace_dlg->show();
}

This callback will replace the next occurrence of the replacement string. If nothing has been entered for the replacement string, then the replace dialog is displayed instead:

void replace2_cb(fltk::Widget*, void* v) {
  EditorWindow* e = (EditorWindow*)v;
  const char *find = e->replace_find->text();
  const char *replace = e->replace_with->text();

  if (find[0] == '\0') {
    // Search string is blank; get a new one...
    e->replace_dlg->show();
    return;
  }

  e->replace_dlg->hide();

  int pos = e->editor->insert_position();
  int found = textbuf->search_forward(pos, find, &pos);

  if (found) {
    // Found a match; update the position and replace text...
    textbuf->select(pos, pos+strlen(find));
    textbuf->remove_selection();
    textbuf->insert(pos, replace);
    textbuf->select(pos, pos+strlen(replace));
    e->editor->insert_position(pos+strlen(replace));
    e->editor->show_insert_position();
  }
  else fltk::alert("No occurrences of \'%s\' found!", find);
}

This callback will replace all occurrences of the search string in the file:

void replall_cb(fltk::Widget*, void* v) {
  EditorWindow* e = (EditorWindow*)v;
  const char *find = e->replace_find->text();
  const char *replace = e->replace_with->text();

  find = e->replace_find->text();
  if (find[0] == '\0') {
    // Search string is blank; get a new one...
    e->replace_dlg->show();
    return;
  }

  e->replace_dlg->hide();

  e->editor->insert_position(0);
  int times = 0;

  // Loop through the whole string
  for (int found = 1; found;) {
    int pos = e->editor->insert_position();
    found = textbuf->search_forward(pos, find, &pos);

    if (found) {
      // Found a match; update the position and replace text...
      textbuf->select(pos, pos+strlen(find));
      textbuf->remove_selection();
      textbuf->insert(pos, replace);
      e->editor->insert_position(pos+strlen(replace));
      e->editor->show_insert_position();
      times++;
    }
  }

  if (times) fltk::message("Replaced %d occurrences.", times);
  else fltk::alert("No occurrences of \'%s\' found!", find);
}

This callback just hides the replace dialog:

void replcan_cb(fltk::Widget*, void* v) {
  EditorWindow* e = (EditorWindow*)v;
  e->replace_dlg->hide();
}

This callback saves the current file. If the current filename is blank it calls the "save as" callback. The save_file() function saves the current file to the specified filename:

void save_cb() {
  if (filename[0] == '\0') {
    // No filename - get one!
    saveas_cb();
    return;
  }
  else save_file(filename);
}

This callback asks the user for a filename and saves the current file. The save_file() function saves the current file to the specified filename:

void saveas_cb() {
  const char *newfile = fltk::file_chooser("Save File As?", "*", filename);
  if (newfile != NULL) save_file(newfile);
}

The undo callback just calls the undo() method:

Other Functions

Now that we've defined the callback functions, we need our support functions to make it all work:

This function checks to see if the current file needs to be saved. If so, it asks the user if they want to save it:

int check_save(void) {
  if (!changed) return 1;

  int r = fltk::choice("The current file has not been saved.\n"
                    "Would you like to save it now?",
                    "Don't Save", "Save", "Cancel");

  if (r == 1) {
    save_cb(); // Save the file...
    return !changed;
  }

This function loads the specified file into the input widget:

int loading = 0;
void load_file(const char *newfile, int ipos) {
  loading = 1;
  int insert = (ipos != -1);
  changed = insert;
  if (!insert) strcpy(filename, "");
  int r;
  if (!insert) r = textbuf->loadfile(newfile);
  else r = textbuf->insertfile(newfile, ipos);
  if (r) {
    if (fltk::ask("File '%s' does not exit. Do you want to create one?", newfile))
      strcpy(filename, newfile);
    else
      strcpy(filename, "");
  } // if

This function saves the current buffer to the specified file:

void save_file(const char *newfile) {
  if (textbuf->savefile(newfile))
    fltk::alert("Error writing to file \'%s\':\n%s.", newfile, strerror(errno));
  else
    strcpy(filename, newfile);
  changed = 0;
  textbuf->call_modify_callbacks();
}

This function sets the changed variable and updates the window label accordingly:

void set_title(fltk::Window* w) {
  if (filename[0] == '\0') strcpy(title, "Untitled.txt");
  else {
    char *slash;
    slash = strrchr(filename, '/');
#ifdef WIN32
    if (slash == NULL) slash = strrchr(filename, '\\');
#endif
    if (slash != NULL) strcpy(title, slash + 1);
    else strcpy(title, filename);
  }

  if (changed) strcat(title, " (modified)");

  w->label(title);
}

Compiling the Editor

The complete source for our text editor can be found in the test/editor.cxx source file. Both the Makefile and Visual C++ workspace include the necessary rules to build the editor. You can also compile it using a standard compiler with:

CC -o editor editor.cxx -lfltk2 -lXext -lX11 -lm

As noted in Fltk Basics Chapter, you may need to include compiler and linker options to tell them where to find the FLTK library. Also, the CC command may also be called gcc or c++ on your system.

Congratulations, you've just built your own text editor!

The Final Product

The final editor window should look like the image below:

Here is all the code in it, in the correct order:

//
// "$Id: editor.cxx 8662 2011-05-15 06:04:24Z bgbnbigben $"
//
// A simple text editor program for the Fast Light Tool Kit (FLTK).
//
// This program is described in Chapter 4 of the FLTK Programmer's Guide.
//
// Copyright 1998-2006 by Bill Spitzak and others.
//
// This library is free software; you can redistribute it and/or
// modify it under the terms of the GNU Library General Public
// License as published by the Free Software Foundation; either
// version 2 of the License, or (at your option) any later version.
//
// This library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
// Library General Public License for more details.
//
// You should have received a copy of the GNU Library General Public
// License along with this library; if not, write to the Free Software
// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
// USA.
//
// Please report all bugs and problems on the following page:
//
//     http://www.fltk.org/str.php
//

//
// Include necessary headers...
//

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <ctype.h>
#include <errno.h>

#include <fltk/run.h>
#include <fltk/events.h>
#include <fltk/Group.h>
#include <fltk/Window.h>
#include <fltk/ask.h>
#include <fltk/file_chooser.h>
#include <fltk/Input.h>
#include <fltk/Button.h>
#include <fltk/ReturnButton.h>
#include <fltk/TextBuffer.h>
#include <fltk/TextEditor.h>
#include <fltk/MenuBuild.h>

int                changed = 0;
char               filename[256] = "";
char               title[256];
fltk::TextBuffer     *textbuf = 0;


// Syntax highlighting stuff...
fltk::TextBuffer     *stylebuf = 0;
fltk::TextDisplay::StyleTableEntry
                   styletable[] = {     // Style table
                     { fltk::BLACK,           fltk::COURIER,        12 }, // A - Plain
                     { fltk::DARK_GREEN,      fltk::COURIER_ITALIC, 12 }, // B - Line comments
                     { fltk::DARK_GREEN,      fltk::COURIER_ITALIC, 12 }, // C - Block comments
                     { fltk::BLUE,            fltk::COURIER,        12 }, // D - Strings
                     { fltk::DARK_RED,        fltk::COURIER,        12 }, // E - Directives
                     { fltk::DARK_RED,        fltk::COURIER_BOLD,   12 }, // F - Types
                     { fltk::BLUE,            fltk::COURIER_BOLD,   12/*, fltk::TextDisplay::ATTR_UNDERLINE*/ }  // G - Keywords
                   };
const char         *code_keywords[] = { // List of known C/C++ keywords...
                     "and",
                     "and_eq",
                     "asm",
                     "bitand",
                     "bitor",
                     "break",
                     "case",
                     "catch",
                     "compl",
                     "continue",
                     "default",
                     "delete",
                     "do",
                     "else",
                     "false",
                     "for",
                     "goto",
                     "if",
                     "new",
                     "not",
                     "not_eq",
                     "operator",
                     "or",
                     "or_eq",
                     "return",
                     "switch",
                     "template",
                     "this",
                     "throw",
                     "true",
                     "try",
                     "using",
                     "while",
                     "xor",
                     "xor_eq"
                   };
const char         *code_types[] = {    // List of known C/C++ types...
                     "auto",
                     "bool",
                     "char",
                     "class",
                     "const",
                     "const_cast",
                     "double",
                     "dynamic_cast",
                     "enum",
                     "explicit",
                     "extern",
                     "float",
                     "friend",
                     "inline",
                     "int",
                     "long",
                     "mutable",
                     "namespace",
                     "private",
                     "protected",
                     "public",
                     "register",
                     "short",
                     "signed",
                     "sizeof",
                     "static",
                     "static_cast",
                     "struct",
                     "template",
                     "typedef",
                     "typename",
                     "union",
                     "unsigned",
                     "virtual",
                     "void",
                     "volatile"
                   };


//
// 'compare_keywords()' - Compare two keywords...
//

extern "C" {
  int
  compare_keywords(const void *a,
                   const void *b) {
    return (strcmp(*((const char **)a), *((const char **)b)));
  }
}

//
// 'style_parse()' - Parse text and produce style data.
//

void
style_parse(const char *text,
            char       *style,
            int        length) {
  char       current;
  int        col;
  int        last;
  char       buf[255],
             *bufptr;
  const char *temp;

  // Style letters:
  //
  // A - Plain
  // B - Line comments
  // C - Block comments
  // D - Strings
  // E - Directives
  // F - Types
  // G - Keywords

  for (current = *style, col = 0, last = 0; length > 0; length --, text ++) {
    if (current == 'B' || current == 'F' || current == 'G') current = 'A';
    if (current == 'A') {
      // Check for directives, comments, strings, and keywords...
      if (col == 0 && *text == '#') {
        // Set style to directive
        current = 'E';
      } else if (strncmp(text, "//", 2) == 0) {
        current = 'B';
        for (; length > 0 && *text != '\n'; length --, text ++) *style++ = 'B';

        if (length == 0) break;
      } else if (strncmp(text, "/*", 2) == 0) {
        current = 'C';
      } else if (strncmp(text, "\\\"", 2) == 0) {
        // Quoted quote...
        *style++ = current;
        *style++ = current;
        text ++;
        length --;
        col += 2;
        continue;
      } else if (*text == '\"') {
        current = 'D';
      } else if (!last && (islower(*text) || *text == '_')) {
        // Might be a keyword...
        for (temp = text, bufptr = buf;
             (islower(*temp) || *temp == '_') && bufptr < (buf + sizeof(buf) - 1);
             *bufptr++ = *temp++);

        if (!islower(*temp) && *temp != '_') {
          *bufptr = '\0';

          bufptr = buf;

          if (bsearch(&bufptr, code_types,
                      sizeof(code_types) / sizeof(code_types[0]),
                      sizeof(code_types[0]), compare_keywords)) {
            while (text < temp) {
              *style++ = 'F';
              text ++;
              length --;
              col ++;
            }

            text --;
            length ++;
            last = 1;
            continue;
          } else if (bsearch(&bufptr, code_keywords,
                             sizeof(code_keywords) / sizeof(code_keywords[0]),
                             sizeof(code_keywords[0]), compare_keywords)) {
            while (text < temp) {
              *style++ = 'G';
              text ++;
              length --;
              col ++;
            }

            text --;
            length ++;
            last = 1;
            continue;
          }
        }
      }
    } else if (current == 'C' && strncmp(text, "*/", 2) == 0) {
      // Close a C comment...
      *style++ = current;
      *style++ = current;
      text ++;
      length --;
      current = 'A';
      col += 2;
      continue;
    } else if (current == 'D') {
      // Continuing in string...
      if (strncmp(text, "\\\"", 2) == 0) {
        // Quoted end quote...
        *style++ = current;
        *style++ = current;
        text ++;
        length --;
        col += 2;
        continue;
      } else if (*text == '\"') {
        // End quote...
        *style++ = current;
        col ++;
        current = 'A';
        continue;
      }
    }

    // Copy style info...
    if (current == 'A' && (*text == '{' || *text == '}')) *style++ = 'G';
    else *style++ = current;
    col ++;

    last = isalnum(*text) || *text == '_' || *text == '.';

    if (*text == '\n') {
      // Reset column and possibly reset the style
      col = 0;
      if (current == 'B' || current == 'E') current = 'A';
    }
  }
}


//
// 'style_init()' - Initialize the style buffer...
//

void
style_init(void) {
  char *style = new char[textbuf->length() + 1];
  const char *text = textbuf->text();

  memset(style, 'A', textbuf->length());
  style[textbuf->length()] = '\0';

  if (!stylebuf) stylebuf = new fltk::TextBuffer(textbuf->length());

  style_parse(text, style, textbuf->length());

  stylebuf->text(style);
  delete[] style;
}


//
// 'style_unfinished_cb()' - Update unfinished styles.
//

void
style_unfinished_cb(int, void*) {
}


//
// 'style_update()' - Update the style buffer...
//

void
style_update(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) {       // I - Callback data
  int   start,                          // Start of text
        end;                            // End of text
  char  last,                           // Last style on line
        *style,                         // Style data
        *text;                          // Text data


  // If this is just a selection change, just unselect the style buffer...
  if (nInserted == 0 && nDeleted == 0) {
    stylebuf->unselect();
    return;
  }

  // Track changes in the text buffer...
  if (nInserted > 0) {
    // Insert characters into the style buffer...
    style = new char[nInserted + 1];
    memset(style, 'A', nInserted);
    style[nInserted] = '\0';

    stylebuf->replace(pos, pos + nDeleted, style);
    delete[] style;
  } else {
    // Just delete characters in the style buffer...
    stylebuf->remove(pos, pos + nDeleted);
  }

  // Select the area that was just updated to avoid unnecessary
  // callbacks...
  stylebuf->select(pos, pos + nInserted - nDeleted);

  // Re-parse the changed region; we do this by parsing from the
  // beginning of the previous line of the changed region to the end of
  // the line of the changed region...  Then we check the last
  // style character and keep updating if we have a multi-line
  // comment character...
  start = textbuf->line_start(pos);
//  if (start > 0) start = textbuf->line_start(start - 1);
  end   = textbuf->line_end(pos + nInserted);
  text  = textbuf->text_range(start, end);
  style = stylebuf->text_range(start, end);
  if (start==end)
    last = 0;
  else
    last  = style[end - start - 1];

//  printf("start = %d, end = %d, text = \"%s\", style = \"%s\", last='%c'...\n",
//         start, end, text, style, last);

  style_parse(text, style, end - start);

//  printf("new style = \"%s\", new last='%c'...\n",
//         style, style[end - start - 1]);

  stylebuf->replace(start, end, style);
  ((fltk::TextEditor *)cbArg)->redisplay_range(start, end);

  if (start==end || last != style[end - start - 1]) {
//    printf("Recalculate the rest of the buffer style\n");
    // Either the user deleted some text, or the last character
    // on the line changed styles, so reparse the
    // remainder of the buffer...
    free(text);
    free(style);

    end   = textbuf->length();
    text  = textbuf->text_range(start, end);
    style = stylebuf->text_range(start, end);

    style_parse(text, style, end - start);

    stylebuf->replace(start, end, style);
    ((fltk::TextEditor *)cbArg)->redisplay_range(start, end);
  }

  free(text);
  free(style);
}


// Editor window functions and class...
void save_cb();
void saveas_cb();
void find2_cb(fltk::Widget*, void*);
void replall_cb(fltk::Widget*, void*);
void replace2_cb(fltk::Widget*, void*);
void replcan_cb(fltk::Widget*, void*);

class EditorWindow : public fltk::Window {
  public:
    EditorWindow(int w, int h, const char* t);
    ~EditorWindow();

    fltk::Window          *replace_dlg;
    fltk::Input           *replace_find;
    fltk::Input           *replace_with;
    fltk::Button          *replace_all;
    fltk::ReturnButton   *replace_next;
    fltk::Button          *replace_cancel;

    fltk::TextEditor     *editor;
    char               search[256];
};

EditorWindow::EditorWindow(int w, int h, const char* t) : fltk::Window(w, h, t) {
  replace_dlg = new fltk::Window(300, 105, "Replace");
  replace_dlg->begin();
    replace_find = new fltk::Input(80, 10, 210, 25, "Find:");
    replace_find->align(fltk::ALIGN_LEFT);

    replace_with = new fltk::Input(80, 40, 210, 25, "Replace:");
    replace_with->align(fltk::ALIGN_LEFT);

    replace_all = new fltk::Button(10, 70, 90, 25, "Replace All");
    replace_all->callback((fltk::Callback *)replall_cb, this);

    replace_next = new fltk::ReturnButton(105, 70, 120, 25, "Replace Next");
    replace_next->callback((fltk::Callback *)replace2_cb, this);

    replace_cancel = new fltk::Button(230, 70, 60, 25, "Cancel");
    replace_cancel->callback((fltk::Callback *)replcan_cb, this);
  replace_dlg->end();
  replace_dlg->set_non_modal();
  editor = 0;
  *search = (char)0;
}

EditorWindow::~EditorWindow() {
  delete replace_dlg;
}

int check_save(void) {
  if (!changed) return 1;

  int r = fltk::choice("The current file has not been saved.\n"
                    "Would you like to save it now?",
                    "Don't Save", "Save", "Cancel");

  if (r == 1) {
    save_cb(); // Save the file...
    return !changed;
  }

  return (r == 2) ? 1 : 0;
}

int loading = 0;
void load_file(const char *newfile, int ipos) {
  loading = 1;
  int insert = (ipos != -1);
  changed = insert;
  if (!insert) strcpy(filename, "");
  int r;
  if (!insert) r = textbuf->loadfile(newfile);
  else r = textbuf->insertfile(newfile, ipos);
  if (r) {
    if (fltk::ask("File '%s' does not exit. Do you want to create one?", newfile))
      strcpy(filename, newfile);
    else
      strcpy(filename, "");
  } // if
  else
    if (!insert) strcpy(filename, newfile);
  loading = 0;
  textbuf->call_modify_callbacks();
}

void save_file(const char *newfile) {
  if (textbuf->savefile(newfile))
    fltk::alert("Error writing to file \'%s\':\n%s.", newfile, strerror(errno));
  else
    strcpy(filename, newfile);
  changed = 0;
  textbuf->call_modify_callbacks();
}

void copy_cb(fltk::Widget*, void* v) {
  EditorWindow* e = (EditorWindow*)v;
  fltk::TextEditor::kf_copy(0, e->editor);
}

void cut_cb(fltk::Widget*, void* v) {
  EditorWindow* e = (EditorWindow*)v;
  fltk::TextEditor::kf_cut(0, e->editor);
}

void delete_cb(fltk::Widget*, void*) {
  textbuf->remove_selection();
}

void find_cb(fltk::Widget* w, void* v) {
  EditorWindow* e = (EditorWindow*)v;
  const char *val;

  val = fltk::input("Search String:", e->search);
  if (val != NULL) {
    // User entered a string - go find it!
    strcpy(e->search, val);
    find2_cb(w, v);
  }
}

void find2_cb(fltk::Widget* w, void* v) {
  EditorWindow* e = (EditorWindow*)v;
  if (e->search[0] == '\0') {
    // Search string is blank; get a new one...
    find_cb(w, v);
    return;
  }

  int pos = e->editor->insert_position();
  int found = textbuf->search_forward(pos, e->search, &pos);
  if (found) {
    // Found a match; select and update the position...
    textbuf->select(pos, pos+strlen(e->search));
    e->editor->insert_position(pos+strlen(e->search));
    e->editor->show_insert_position();
  }
  else fltk::alert("No occurrences of \'%s\' found!", e->search);
}

void set_title(fltk::Window* w) {
  if (filename[0] == '\0') strcpy(title, "Untitled.txt");
  else {
    char *slash;
    slash = strrchr(filename, '/');
#ifdef WIN32
    if (slash == NULL) slash = strrchr(filename, '\\');
#endif
    if (slash != NULL) strcpy(title, slash + 1);
    else strcpy(title, filename);
  }

  if (changed) strcat(title, " (modified)");

  w->label(title);
}

void changed_cb(int, int nInserted, int nDeleted,int, const char*, void* v) {
  if ((nInserted || nDeleted) && !loading) changed = 1;
  EditorWindow *w = (EditorWindow *)v;
  set_title(w);
  if (loading) w->editor->show_insert_position();
}

void new_cb(fltk::Widget*, void*) {
  if (!check_save()) return;

  filename[0] = '\0';
  textbuf->select(0, textbuf->length());
  textbuf->remove_selection();
  changed = 0;
  textbuf->call_modify_callbacks();
}

void open_cb(fltk::Widget*, void*) {
  if (!check_save()) return;

  const char *newfile = fltk::file_chooser("Open File?", "*", filename);
  if (newfile != NULL) load_file(newfile, -1);
}

void insert_cb(fltk::Widget*, void *v) {
  const char *newfile = fltk::file_chooser("Insert File?", "*", filename);
  EditorWindow *w = (EditorWindow *)v;
  if (newfile != NULL) load_file(newfile, w->editor->insert_position());
}

void paste_cb(fltk::Widget*, void* v) {
  EditorWindow* e = (EditorWindow*)v;
  fltk::TextEditor::kf_paste(0, e->editor);
}

int num_windows = 0;

void close_cb(fltk::Widget*, void* v) {
  fltk::Window* w = (fltk::Window*)v;
  if (num_windows == 1 && !check_save()) {
    return;
  }

  w->hide();
  textbuf->remove_modify_callback(changed_cb, w);
  delete w;
  num_windows--;
  if (!num_windows) exit(0);
}

void quit_cb(fltk::Widget*, void*) {
  if (changed && !check_save())
    return;

  exit(0);
}

void replace_cb(fltk::Widget*, void* v) {
  EditorWindow* e = (EditorWindow*)v;
  e->replace_dlg->show();
}

void replace2_cb(fltk::Widget*, void* v) {
  EditorWindow* e = (EditorWindow*)v;
  const char *find = e->replace_find->text();
  const char *replace = e->replace_with->text();

  if (find[0] == '\0') {
    // Search string is blank; get a new one...
    e->replace_dlg->show();
    return;
  }

  e->replace_dlg->hide();

  int pos = e->editor->insert_position();
  int found = textbuf->search_forward(pos, find, &pos);

  if (found) {
    // Found a match; update the position and replace text...
    textbuf->select(pos, pos+strlen(find));
    textbuf->remove_selection();
    textbuf->insert(pos, replace);
    textbuf->select(pos, pos+strlen(replace));
    e->editor->insert_position(pos+strlen(replace));
    e->editor->show_insert_position();
  }
  else fltk::alert("No occurrences of \'%s\' found!", find);
}

void replall_cb(fltk::Widget*, void* v) {
  EditorWindow* e = (EditorWindow*)v;
  const char *find = e->replace_find->text();
  const char *replace = e->replace_with->text();

  find = e->replace_find->text();
  if (find[0] == '\0') {
    // Search string is blank; get a new one...
    e->replace_dlg->show();
    return;
  }

  e->replace_dlg->hide();

  e->editor->insert_position(0);
  int times = 0;

  // Loop through the whole string
  for (int found = 1; found;) {
    int pos = e->editor->insert_position();
    found = textbuf->search_forward(pos, find, &pos);

    if (found) {
      // Found a match; update the position and replace text...
      textbuf->select(pos, pos+strlen(find));
      textbuf->remove_selection();
      textbuf->insert(pos, replace);
      e->editor->insert_position(pos+strlen(replace));
      e->editor->show_insert_position();
      times++;
    }
  }

  if (times) fltk::message("Replaced %d occurrences.", times);
  else fltk::alert("No occurrences of \'%s\' found!", find);
}

void replcan_cb(fltk::Widget*, void* v) {
  EditorWindow* e = (EditorWindow*)v;
  e->replace_dlg->hide();
}

void save_cb() {
  if (filename[0] == '\0') {
    // No filename - get one!
    saveas_cb();
    return;
  }
  else save_file(filename);
}

void saveas_cb() {
  const char *newfile = fltk::file_chooser("Save File As?", "*", filename);
  if (newfile != NULL) save_file(newfile);
}

fltk::Window* new_view();

void view_cb(fltk::Widget*, void*) {
  fltk::Window* w = new_view();
  w->show();
}

static void build_menus(fltk::MenuBar * menu, fltk::Widget *w) {
    fltk::ItemGroup * g;
    menu->user_data(w);
    menu->begin();
      g = new fltk::ItemGroup( "&File" );
      g->begin();
        new fltk::Item( "&New File",        0, (fltk::Callback *)new_cb );
        new fltk::Item( "&Open File...",    fltk::COMMAND + 'O', (fltk::Callback *)open_cb );
        new fltk::Item( "&Insert File...",  fltk::COMMAND + 'I', (fltk::Callback *)insert_cb);
        new fltk::Divider();
        new fltk::Item( "&Save File",       fltk::COMMAND + 'S', (fltk::Callback *)save_cb );
        new fltk::Item( "Save File &As...", fltk::COMMAND + fltk::SHIFT + 'S', (fltk::Callback *)saveas_cb);
        new fltk::Divider();
        new fltk::Item( "New &View", fltk::ACCELERATOR + 'V', (fltk::Callback *)view_cb, 0 );
        new fltk::Item( "&Close View", fltk::COMMAND + 'W', (fltk::Callback *)close_cb);
        new fltk::Divider();
        new fltk::Item( "E&xit", fltk::COMMAND + 'Q', (fltk::Callback *)quit_cb, 0 );
      g->end();
      g = new fltk::ItemGroup( "&Edit" );
      g->begin();
        new fltk::Item( "Cu&t",        fltk::COMMAND + 'X', (fltk::Callback *)cut_cb );
        new fltk::Item( "&Copy",       fltk::COMMAND + 'C', (fltk::Callback *)copy_cb );
        new fltk::Item( "&Paste",      fltk::COMMAND + 'V', (fltk::Callback *)paste_cb );
        new fltk::Item( "&Delete",     0, (fltk::Callback *)delete_cb );
      g->end();
      g = new fltk::ItemGroup( "&Search" );
      g->begin();
        new fltk::Item( "&Find...",       fltk::COMMAND + 'F', (fltk::Callback *)find_cb );
        new fltk::Item( "F&ind Again",    fltk::COMMAND + 'G', find2_cb );
        new fltk::Item( "&Replace...",    fltk::COMMAND + 'R', replace_cb );
        new fltk::Item( "Re&place Again", fltk::COMMAND + 'T', replace2_cb );
      g->end();
    menu->end();
}

fltk::Window* new_view() {
  EditorWindow* w = new EditorWindow(660, 400, title);
  w->begin();
    fltk::MenuBar* m = new fltk::MenuBar(0, 0, 660, 21);
    build_menus(m,w);
    w->editor = new fltk::TextEditor(0, 21, 660, 379);
    w->editor->buffer(textbuf);
    w->editor->highlight_data(stylebuf, styletable,
      sizeof(styletable) / sizeof(styletable[0]),
     'A', style_unfinished_cb, 0);
    w->editor->textfont(fltk::COURIER);
  w->end();
  w->resizable(w->editor);
  w->callback((fltk::Callback *)close_cb, w);

  w->editor->linenumber_width(60);
  w->editor->wrap_mode(true, 0);
  w->editor->cursor_style(fltk::TextDisplay::BLOCK_CURSOR);
  // w->editor->insert_mode(false);

  textbuf->add_modify_callback(style_update, w->editor);
  textbuf->add_modify_callback(changed_cb, w);
  textbuf->call_modify_callbacks();
  num_windows++;
  return w;
}

int main(int argc, char **argv) {

  textbuf = new fltk::TextBuffer(0);
  style_init();

  fltk::Window* window = new_view();

  window->show(1, argv);

  if (argc > 1) {
    window->label(" "); // Prevent from displaying "Untitled.txt" before its time...
    load_file(argv[1], -1);
  }

  return fltk::run();
}

//
// End of "$Id: editor.cxx 8662 2011-05-15 06:04:24Z bgbnbigben $".
//