MODULE sourceview ;

(*
   m2-GTK4 example - a small source-code editor built from
   GtkSourceView 5:

     GtkApplicationWindow > GtkScrolledWindow > GtkSourceView
       driven by a GtkSourceBuffer with the "C" language definition and
       the "Adwaita" style scheme, line numbers, current-line highlight
       and a 4-column tab width.

   Build:  make examples
   Run:    ./build/examples/sourceview
*)

FROM Gio IMPORT g_application_run;
FROM GtkApplication IMPORT gtk_application_new;
FROM GtkWindow IMPORT gtk_application_window_new, gtk_window_set_title,
   gtk_window_set_default_size, gtk_window_set_child, gtk_window_present;
FROM GtkScrolledWindow IMPORT gtk_scrolled_window_new,
   gtk_scrolled_window_set_child;
FROM GtkWidget IMPORT gtk_widget_set_vexpand;
FROM GtkTextBuffer IMPORT gtk_text_buffer_set_text;
FROM GtkUtils IMPORT Connect;
FROM GtkSourceFunctions IMPORT gtk_source_init;
FROM GtkSourceBuffer IMPORT gtk_source_buffer_new,
   gtk_source_buffer_set_language, gtk_source_buffer_set_style_scheme;
FROM GtkSourceLanguageManager IMPORT gtk_source_language_manager_get_default,
   gtk_source_language_manager_get_language;
FROM GtkSourceStyleSchemeManager IMPORT
   gtk_source_style_scheme_manager_get_default,
   gtk_source_style_scheme_manager_get_scheme;
FROM GtkSourceView IMPORT gtk_source_view_new_with_buffer,
   gtk_source_view_set_show_line_numbers,
   gtk_source_view_set_highlight_current_line, gtk_source_view_set_tab_width;
FROM SYSTEM IMPORT ADDRESS, ADR;
FROM libc IMPORT printf;

CONST
   AppId = "org.example.m2gtk4.SourceView";

   Sample =
"/* hello.c - a tiny C program */\n" +
"#include <stdio.h>\n" +
"\n" +
"int main (int argc, char **argv)\n" +
"{\n" +
"  for (int i = 0; i < 3; i++)\n" +
"    printf ('Hello, GNU Modula-2 + GtkSourceView! (%d)\\n', i);\n" +
"  return 0;\n" +
"}\n";

PROCEDURE OnActivate (application: ADDRESS; data: ADDRESS);
VAR
   window, sw, view, buffer, lang, scheme: ADDRESS;
BEGIN
   buffer := gtk_source_buffer_new(NIL);

   lang := gtk_source_language_manager_get_language
              (gtk_source_language_manager_get_default(), "c");
   IF lang # NIL THEN
      gtk_source_buffer_set_language(buffer, lang)
   END;

   scheme := gtk_source_style_scheme_manager_get_scheme
                (gtk_source_style_scheme_manager_get_default(), "Adwaita");
   IF scheme # NIL THEN
      gtk_source_buffer_set_style_scheme(buffer, scheme)
   END;

   gtk_text_buffer_set_text(buffer, Sample, -1);

   view := gtk_source_view_new_with_buffer(buffer);
   gtk_source_view_set_show_line_numbers(view, 1);
   gtk_source_view_set_highlight_current_line(view, 1);
   gtk_source_view_set_tab_width(view, 4);

   sw := gtk_scrolled_window_new();
   gtk_scrolled_window_set_child(sw, view);
   gtk_widget_set_vexpand(sw, 1);

   window := gtk_application_window_new(application);
   gtk_window_set_title(window, "m2-GTK4 - GtkSourceView");
   gtk_window_set_default_size(window, 640, 480);
   gtk_window_set_child(window, sw);
   gtk_window_present(window)
END OnActivate;

VAR
   app: ADDRESS;
BEGIN
   gtk_source_init();
   app := gtk_application_new(AppId, 0);
   IF app = NIL THEN
      printf("gtk_application_new failed\n");
      HALT(1)
   END;
   Connect(app, "activate", ADR(OnActivate), NIL);
   g_application_run(app, 0, NIL)
END sourceview.