MODULE editor ;

(*
   m2-GTK4 example - a small editor built from the second input batch.

   A GtkSearchEntry, a GtkTextView (in a GtkScrolledWindow) backed by a
   GtkTextBuffer, a GtkDropDown that selects the wrap mode, and a
   GtkSpinButton that sets the text padding.  The signals use the
   GtkClosures helper (2- and 3-argument forms).

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

FROM Gio IMPORT g_application_run;
FROM GtkApplication IMPORT gtk_application_new;
FROM GtkApplicationWindow IMPORT gtk_application_window_new;
FROM GtkWindow IMPORT gtk_window_set_title, gtk_window_set_default_size,
   gtk_window_set_child, gtk_window_present;
FROM GtkBox IMPORT gtk_box_new, gtk_box_append, gtk_box_set_spacing;
FROM GtkEnums IMPORT GtkVertical, GtkHorizontal, GtkWrapWord;
FROM GtkLabel IMPORT gtk_label_new, gtk_label_set_text;
FROM GtkWidget IMPORT gtk_widget_set_margin_top,
   gtk_widget_set_margin_bottom, gtk_widget_set_margin_start,
   gtk_widget_set_margin_end, gtk_widget_set_vexpand;
FROM GtkSearchEntry IMPORT gtk_search_entry_new,
   gtk_search_entry_set_placeholder_text;
FROM GtkEditable IMPORT gtk_editable_get_text;
FROM GtkScrolledWindow IMPORT gtk_scrolled_window_new,
   gtk_scrolled_window_set_child, gtk_scrolled_window_set_policy,
   GtkPolicyNever, GtkPolicyAutomatic;
FROM GtkTextView IMPORT gtk_text_view_new, gtk_text_view_get_buffer,
   gtk_text_view_set_wrap_mode, gtk_text_view_set_monospace,
   gtk_text_view_set_left_margin, gtk_text_view_set_right_margin;
FROM GtkTextBuffer IMPORT gtk_text_buffer_set_text;
FROM GtkStringList IMPORT gtk_string_list_new, gtk_string_list_append;
FROM GtkDropDown IMPORT gtk_drop_down_new, gtk_drop_down_get_selected,
   gtk_drop_down_set_selected;
FROM GtkSpinButton IMPORT gtk_spin_button_new_with_range,
   gtk_spin_button_get_value, gtk_spin_button_set_value;
FROM GtkClosures IMPORT Connect2, Connect3;
FROM GtkUtils IMPORT CStrToM2, StrAppend;
FROM SYSTEM IMPORT ADDRESS, ADR;
FROM libc IMPORT printf;

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

VAR
   view, status: ADDRESS;

PROCEDURE OnSearch (entry: ADDRESS; user: ADDRESS);
VAR
   text: ARRAY [0..63] OF CHAR;
   line: ARRAY [0..95] OF CHAR;
BEGIN
   line[0] := 0C;
   StrAppend(line, "search: ");
   CStrToM2(gtk_editable_get_text(entry), text);
   IF text[0] = 0C THEN
      StrAppend(line, "(none)")
   ELSE
      StrAppend(line, text)
   END;
   gtk_label_set_text(status, line)
END OnSearch;

(* 3-argument form: "notify::selected" carries the GParamSpec *)
PROCEDURE OnWrap (dd: ADDRESS; pspec: ADDRESS; user: ADDRESS);
BEGIN
   gtk_text_view_set_wrap_mode(view, gtk_drop_down_get_selected(dd))
END OnWrap;

PROCEDURE OnPad (spin: ADDRESS; user: ADDRESS);
VAR
   margin: INTEGER;
BEGIN
   margin := TRUNC(gtk_spin_button_get_value(spin));
   gtk_text_view_set_left_margin(view, margin);
   gtk_text_view_set_right_margin(view, margin)
END OnPad;

PROCEDURE OnActivate (application: ADDRESS; data: ADDRESS);
VAR
   window, box, search, scroller, bottom, wrapLabel, padLabel,
   dd, list, spin, buffer: ADDRESS;
BEGIN
   status := gtk_label_new("Type in the box or search");

   (* text view inside a scrolled window *)
   view := gtk_text_view_new();
   gtk_text_view_set_monospace(view, 1);
   buffer := gtk_text_view_get_buffer(view);
   gtk_text_buffer_set_text(buffer, "Edit me!", -1);
   gtk_text_view_set_left_margin(view, 6);
   gtk_text_view_set_right_margin(view, 6);

   scroller := gtk_scrolled_window_new();
   gtk_scrolled_window_set_policy(scroller, GtkPolicyNever,
                                  GtkPolicyAutomatic);
   gtk_scrolled_window_set_child(scroller, view);
   gtk_widget_set_vexpand(scroller, 1);

   (* search entry *)
   search := gtk_search_entry_new();
   gtk_search_entry_set_placeholder_text(search, "search the text");
   Connect2(search, "search-changed", OnSearch, NIL);

   (* wrap-mode drop-down *)
   list := gtk_string_list_new(NIL);
   gtk_string_list_append(list, "No wrap");
   gtk_string_list_append(list, "Wrap chars");
   gtk_string_list_append(list, "Wrap words");
   gtk_string_list_append(list, "Wrap words/chars");
   dd := gtk_drop_down_new(list, NIL);
   gtk_drop_down_set_selected(dd, 2);
   gtk_text_view_set_wrap_mode(view, GtkWrapWord);
   Connect3(dd, "notify::selected", OnWrap, NIL);

   (* padding spin button *)
   spin := gtk_spin_button_new_with_range(0.0, 40.0, 1.0);
   gtk_spin_button_set_value(spin, 6.0);
   Connect2(spin, "value-changed", OnPad, NIL);

   wrapLabel := gtk_label_new("Wrap:");
   padLabel := gtk_label_new("Padding:");
   bottom := gtk_box_new(GtkHorizontal, 8);
   gtk_box_append(bottom, wrapLabel);
   gtk_box_append(bottom, dd);
   gtk_box_append(bottom, padLabel);
   gtk_box_append(bottom, spin);

   box := gtk_box_new(GtkVertical, 8);
   gtk_box_set_spacing(box, 8);
   gtk_widget_set_margin_top(box, 12);
   gtk_widget_set_margin_bottom(box, 12);
   gtk_widget_set_margin_start(box, 12);
   gtk_widget_set_margin_end(box, 12);
   gtk_box_append(box, search);
   gtk_box_append(box, scroller);
   gtk_box_append(box, bottom);
   gtk_box_append(box, status);

   window := gtk_application_window_new(application);
   gtk_window_set_title(window, "m2-GTK4 Editor");
   gtk_window_set_default_size(window, 520, 360);
   gtk_window_set_child(window, box);
   gtk_window_present(window)
END OnActivate;

VAR
   app: ADDRESS;
BEGIN
   app := gtk_application_new(AppId, 0);
   IF app = NIL THEN
      printf("gtk_application_new failed\n");
      HALT(1)
   END;
   Connect2(app, "activate", OnActivate, NIL);
   g_application_run(app, 0, NIL)
END editor.