/* Haiku window system support
   Copyright (C) 2021 Free Software Foundation, Inc.

This file is part of GNU Emacs.

GNU Emacs is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or (at
your option) any later version.

GNU Emacs 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 General Public License for more details.

You should have received a copy of the GNU General Public License
along with GNU Emacs.  If not, see <https://www.gnu.org/licenses/>.  */

#include <config.h>

#include "lisp.h"
#include "keyboard.h"
#include "menu.h"
#include "buffer.h"
#include "blockinput.h"

#include "haikuterm.h"
#include "haiku_support.h"

static Lisp_Object *volatile menu_item_selection;

int popup_activated_p = 0;

struct submenu_stack_cell
{
  void *parent_menu;
  void *pane;
};

static void
digest_menu_items (void *first_menu, int start, int menu_items_used,
		   int mbar_p)
{
  void **menus, **panes;
  ssize_t menu_len = (menu_items_used + 1 - start) * sizeof *menus;
  ssize_t pane_len = (menu_items_used + 1 - start) * sizeof *panes;

  menus = alloca (menu_len);
  panes = alloca (pane_len);

  int i = start, menu_depth = 0;

  memset (menus, 0, menu_len);
  memset (panes, 0, pane_len);

  void *menu = first_menu;

  menus[0] = first_menu;

  while (i < menu_items_used)
    {
      if (NILP (AREF (menu_items, i)))
	{
	  menus[++menu_depth] = menu;
	  i++;
	}
      else if (EQ (AREF (menu_items, i), Qlambda))
	{
	  panes[menu_depth] = NULL;
	  menu = panes[--menu_depth] ? panes[menu_depth] : menus[menu_depth];
	  i++;
	}
      else if (EQ (AREF (menu_items, i), Qquote))
	i += 1;
      else if (EQ (AREF (menu_items, i), Qt))
	{
	  Lisp_Object pane_name, prefix;
	  const char *pane_string;

	  if (menu_items_n_panes == 1)
	    {
	      i += MENU_ITEMS_PANE_LENGTH;
	      continue;
	    }

	  pane_name = AREF (menu_items, i + MENU_ITEMS_PANE_NAME);
	  prefix = AREF (menu_items, i + MENU_ITEMS_PANE_PREFIX);

	  if (STRINGP (pane_name) && STRING_MULTIBYTE (pane_name))
	    {
	      pane_name = ENCODE_UTF_8 (pane_name);
	      ASET (menu_items, i + MENU_ITEMS_PANE_NAME, pane_name);
	    }

	  pane_string = (NILP (pane_name)
			 ? "" : SSDATA (pane_name));
	  if (!NILP (prefix))
	    pane_string++;

	  if (strcmp (pane_string, ""))
	    {
	      panes[menu_depth] =
		menu = BMenu_new_submenu (menus[menu_depth], pane_string, 1);
	    }

	  i += MENU_ITEMS_PANE_LENGTH;
	}
      else
	{
	  Lisp_Object item_name, enable, descrip, def, selected;
	  item_name = AREF (menu_items, i + MENU_ITEMS_ITEM_NAME);
	  enable = AREF (menu_items, i + MENU_ITEMS_ITEM_ENABLE);
	  descrip = AREF (menu_items, i + MENU_ITEMS_ITEM_EQUIV_KEY);
	  def = AREF (menu_items, i + MENU_ITEMS_ITEM_DEFINITION);
	  selected = AREF (menu_items, i + MENU_ITEMS_ITEM_SELECTED);

	  if (STRINGP (item_name) && STRING_MULTIBYTE (item_name))
	    {
	      item_name = ENCODE_UTF_8 (item_name);
	      ASET (menu_items, i + MENU_ITEMS_ITEM_NAME, item_name);
	    }

	  if (STRINGP (descrip) && STRING_MULTIBYTE (descrip))
	    {
	      descrip = ENCODE_UTF_8 (descrip);
	      ASET (menu_items, i + MENU_ITEMS_ITEM_EQUIV_KEY, descrip);
	    }

	  if (i + MENU_ITEMS_ITEM_LENGTH < menu_items_used &&
	      NILP (AREF (menu_items, i + MENU_ITEMS_ITEM_LENGTH)))
	    menu = BMenu_new_submenu (menu, SSDATA (item_name), !NILP (enable));
	  else if (NILP (def) && menu_separator_name_p (SSDATA (item_name)))
	    BMenu_add_separator (menu);
	  else if (!mbar_p)
	    BMenu_add_item (menu, SSDATA (item_name),
			    !NILP (def) ? aref_addr (menu_items, i) : NULL,
			    !NILP (enable), !NILP (selected));
	  else
	    BMenu_add_item (menu, SSDATA (item_name),
			    !NILP (def) ? (void *) (intptr_t) i : NULL,
			    !NILP (enable), !NILP (selected));

	  i += MENU_ITEMS_ITEM_LENGTH;
	}
    }
}

static Lisp_Object
haiku_dialog_show (struct frame *f, Lisp_Object title,
		   Lisp_Object header, const char **error_name)
{
  int i, nb_buttons = 0;

  *error_name = NULL;

  if (menu_items_n_panes > 1)
    {
      *error_name = "Multiple panes in dialog box";
      return Qnil;
    }

  Lisp_Object pane_name = AREF (menu_items, MENU_ITEMS_PANE_NAME);
  i = MENU_ITEMS_PANE_LENGTH;

  if (STRING_MULTIBYTE (pane_name))
    pane_name = ENCODE_UTF_8 (pane_name);

  block_input ();
  void *alert = BAlert_new (SSDATA (pane_name), NILP (header) ? HAIKU_INFO_ALERT :
			    HAIKU_IDEA_ALERT);

  Lisp_Object vals[10];

  while (i < menu_items_used)
    {
      Lisp_Object item_name, enable, descrip, value;
      item_name = AREF (menu_items, i + MENU_ITEMS_ITEM_NAME);
      enable = AREF (menu_items, i + MENU_ITEMS_ITEM_ENABLE);
      descrip = AREF (menu_items, i + MENU_ITEMS_ITEM_EQUIV_KEY);
      value = AREF (menu_items, i + MENU_ITEMS_ITEM_VALUE);

      if (NILP (item_name))
	{
	  BAlert_delete (alert);
	  *error_name = "Submenu in dialog items";
	  unblock_input ();
	  return Qnil;
	}

      if (EQ (item_name, Qquote))
	{
	  i++;
	}

      if (nb_buttons >= 9)
	{
	  BAlert_delete (alert);
	  *error_name = "Too many dialog items";
	  unblock_input ();
	  return Qnil;
	}

      if (STRING_MULTIBYTE (item_name))
	item_name = ENCODE_UTF_8 (item_name);
      if (!NILP (descrip) && STRING_MULTIBYTE (descrip))
	descrip = ENCODE_UTF_8 (descrip);

      void *button = BAlert_add_button (alert, SSDATA (item_name));
      BButton_set_enabled (button, !NILP (enable));
      if (!NILP (descrip))
	BView_set_tooltip (button, SSDATA (descrip));

      vals[nb_buttons] = value;
      ++nb_buttons;
      i += MENU_ITEMS_ITEM_LENGTH;
    }

  int32_t val = BAlert_go (alert);
  unblock_input ();

  if (val < 0)
    quit ();
  else
    return vals[val];

  return Qnil;
}

Lisp_Object
haiku_popup_dialog (struct frame *f, Lisp_Object header, Lisp_Object contents)
{
  Lisp_Object title;
  const char *error_name = NULL;
  Lisp_Object selection;
  ptrdiff_t specpdl_count = SPECPDL_INDEX ();

  check_window_system (f);

  /* Decode the dialog items from what was specified.  */
  title = Fcar (contents);
  CHECK_STRING (title);
  record_unwind_protect_void (unuse_menu_items);

  if (NILP (Fcar (Fcdr (contents))))
    /* No buttons specified, add an "Ok" button so users can pop down
       the dialog.  Also, the lesstif/motif version crashes if there are
       no buttons.  */
    contents = list2 (title, Fcons (build_string ("Ok"), Qt));

  list_of_panes (list1 (contents));

  /* Display them in a dialog box.  */
  block_input ();
  selection = haiku_dialog_show (f, title, header, &error_name);
  unblock_input ();

  unbind_to (specpdl_count, Qnil);
  discard_menu_items ();

  if (error_name)
    error ("%s", error_name);
  return selection;
}

Lisp_Object
haiku_menu_show (struct frame *f, int x, int y, int menuflags,
		 Lisp_Object title, const char **error_name)
{
  int i = 0, submenu_depth = 0;
  void *view = FRAME_HAIKU_VIEW (f);
  void *menu;

  Lisp_Object *subprefix_stack =
    alloca (menu_items_used * sizeof (Lisp_Object));

  eassert (FRAME_HAIKU_P (f));

  *error_name = NULL;

  if (menu_items_used <= MENU_ITEMS_PANE_LENGTH)
    {
      *error_name = "Empty menu";
      return Qnil;
    }

  block_input ();

  if (STRINGP (title) && STRING_MULTIBYTE (title))
    title = ENCODE_UTF_8 (title);

  menu = BPopUpMenu_new (STRINGP (title) ? SSDATA (title) : NULL);

  digest_menu_items (menu, 0, menu_items_used, 0);

  BView_convert_to_screen (view, &x, &y);
  menu_item_selection = BMenu_run (menu, x, y);

  if (menu_item_selection)
    {
      Lisp_Object prefix, entry;

      prefix = entry = Qnil;
      i = 0;
      while (i < menu_items_used)
	{
	  if (NILP (AREF (menu_items, i)))
	    {
	      subprefix_stack[submenu_depth++] = prefix;
	      prefix = entry;
	      i++;
	    }
	  else if (EQ (AREF (menu_items, i), Qlambda))
	    {
	      prefix = subprefix_stack[--submenu_depth];
	      i++;
	    }
	  else if (EQ (AREF (menu_items, i), Qt))
	    {
	      prefix
		= AREF (menu_items, i + MENU_ITEMS_PANE_PREFIX);
	      i += MENU_ITEMS_PANE_LENGTH;
	    }
	  /* Ignore a nil in the item list.
	     It's meaningful only for dialog boxes.  */
	  else if (EQ (AREF (menu_items, i), Qquote))
	    i += 1;
	  else
	    {
	      entry
		= AREF (menu_items, i + MENU_ITEMS_ITEM_VALUE);
	      if (menu_item_selection == aref_addr (menu_items, i))
		{
		  if (menuflags & MENU_KEYMAPS)
		    {
		      int j;

		      entry = list1 (entry);
		      if (!NILP (prefix))
			entry = Fcons (prefix, entry);
		      for (j = submenu_depth - 1; j >= 0; j--)
			if (!NILP (subprefix_stack[j]))
			  entry = Fcons (subprefix_stack[j], entry);
		    }
		  BPopUpMenu_delete (menu);
		  unblock_input ();
		  return entry;
		}
	      i += MENU_ITEMS_ITEM_LENGTH;
	    }
	}
    }
  else if (!(menuflags & MENU_FOR_CLICK))
    {
      BPopUpMenu_delete (menu);
      unblock_input ();
      quit ();
    }
  BPopUpMenu_delete (menu);
  unblock_input ();
  return Qnil;
}

void
free_frame_menubar (struct frame *f)
{
  FRAME_MENU_BAR_LINES (f) = 0;
  FRAME_MENU_BAR_HEIGHT (f) = 0;
  FRAME_EXTERNAL_MENU_BAR (f) = 0;

  block_input ();
  void *mbar = FRAME_HAIKU_MENU_BAR (f);
  if (mbar)
    BMenuBar_delete (mbar);
  unblock_input ();

  adjust_frame_size (f, -1, -1, 2, false, Qmenu_bar_lines);
}

void
initialize_frame_menubar (struct frame *f)
{
  /* This function is called before the first chance to redisplay
     the frame.  It has to be, so the frame will have the right size.  */
  fset_menu_bar_items (f, menu_bar_items (FRAME_MENU_BAR_ITEMS (f)));
  set_frame_menubar (f, true);
}

void
set_frame_menubar (struct frame *f, bool deep_p)
{
  void *mbar = FRAME_HAIKU_MENU_BAR (f);
  void *view = FRAME_HAIKU_VIEW (f);

  int first_time_p = 0;

  if (!mbar)
    {
      mbar = FRAME_HAIKU_MENU_BAR (f) = BMenuBar_new (view);
      first_time_p = 1;
    }

  Lisp_Object items;
  struct buffer *prev = current_buffer;
  Lisp_Object buffer;
  ptrdiff_t specpdl_count = SPECPDL_INDEX ();
  int previous_menu_items_used = f->menu_bar_items_used;
  Lisp_Object *previous_items
    = alloca (previous_menu_items_used * sizeof *previous_items);

  XSETFRAME (Vmenu_updating_frame, f);

  if (!deep_p)
    {
      FRAME_OUTPUT_DATA (f)->menu_up_to_date_p = 0;
      items = FRAME_MENU_BAR_ITEMS (f);
      Lisp_Object string;

      block_input ();
      int count = BMenu_count_items (mbar);

      int i;
      for (i = 0; i < ASIZE (items); i += 4)
	{
	  string = AREF (items, i + 1);

	  if (!STRINGP (string))
	    break;

	  if (STRING_MULTIBYTE (string))
	    string = ENCODE_UTF_8 (string);

	  if (i / 4 < count)
	    {
	      void *it = BMenu_item_at (mbar, i / 4);
	      BMenu_item_set_label (it, SSDATA (string));
	    }
	  else
	    BMenu_new_menu_bar_submenu (mbar, SSDATA (string));
	}

      if (i / 4 < count)
	BMenu_delete_from (mbar, i / 4, count - i / 4 + 1);
      unblock_input ();

      f->menu_bar_items_used = 0;
    }
  else
    {
      /* If we are making a new widget, its contents are empty,
	 do always reinitialize them.  */
      if (first_time_p)
	previous_menu_items_used = 0;
      buffer = XWINDOW (FRAME_SELECTED_WINDOW (f))->contents;
      specbind (Qinhibit_quit, Qt);
      /* Don't let the debugger step into this code
	 because it is not reentrant.  */
      specbind (Qdebug_on_next_call, Qnil);

      record_unwind_save_match_data ();
      if (NILP (Voverriding_local_map_menu_flag))
	{
	  specbind (Qoverriding_terminal_local_map, Qnil);
	  specbind (Qoverriding_local_map, Qnil);
	}

      set_buffer_internal_1 (XBUFFER (buffer));

      /* Run the Lucid hook.  */
      safe_run_hooks (Qactivate_menubar_hook);

      /* If it has changed current-menubar from previous value,
	 really recompute the menubar from the value.  */
      if (! NILP (Vlucid_menu_bar_dirty_flag))
	call0 (Qrecompute_lucid_menubar);
      safe_run_hooks (Qmenu_bar_update_hook);
      fset_menu_bar_items (f, menu_bar_items (FRAME_MENU_BAR_ITEMS (f)));

      items = FRAME_MENU_BAR_ITEMS (f);

      /* Save the frame's previous menu bar contents data.  */
      if (previous_menu_items_used)
	memcpy (previous_items, xvector_contents (f->menu_bar_vector),
		previous_menu_items_used * word_size);

      /* Fill in menu_items with the current menu bar contents.
	 This can evaluate Lisp code.  */
      save_menu_items ();
      menu_items = f->menu_bar_vector;
      menu_items_allocated = VECTORP (menu_items) ? ASIZE (menu_items) : 0;
      init_menu_items ();
      int i;
      int count = BMenu_count_items (mbar);
      int subitems = ASIZE (items) / 4;

      int *submenu_start, *submenu_end,	*submenu_n_panes;
      Lisp_Object *submenu_names;

      submenu_start = alloca ((subitems + 1) * sizeof *submenu_start);
      submenu_end = alloca (subitems * sizeof *submenu_end);
      submenu_n_panes = alloca (subitems * sizeof *submenu_n_panes);
      submenu_names = alloca (subitems * sizeof (Lisp_Object));

      for (i = 0; i < subitems; ++i)
	{
	  Lisp_Object key, string, maps;

	  key = AREF (items, i * 4);
	  string = AREF (items, i * 4 + 1);
	  maps = AREF (items, i * 4 + 2);

	  if (NILP (string))
	    break;

	  if (STRINGP (string) && STRING_MULTIBYTE (string))
	    string = ENCODE_UTF_8 (string);

	  submenu_start[i] = menu_items_used;
	  menu_items_n_panes = 0;
	  parse_single_submenu (key, string, maps);
	  submenu_n_panes[i] = menu_items_n_panes;
	  submenu_end[i] = menu_items_used;
	  submenu_names[i] = string;
	}
      finish_menu_items ();
      submenu_start[i] = -1;

      block_input ();
      for (i = 0; submenu_start[i] >= 0; ++i)
	{
	  void *mn = NULL;
	  if (i < count)
	    mn = BMenu_item_get_menu (BMenu_item_at (mbar, i));
	  if (mn)
	    BMenu_delete_all (mn);
	  else
	    mn = BMenu_new_menu_bar_submenu (mbar, SSDATA (submenu_names[i]));

	  menu_items_n_panes = submenu_n_panes[i];
	  digest_menu_items (mn, submenu_start[i], submenu_end[i], 1);
	}
      unblock_input ();

      set_buffer_internal_1 (prev);

      FRAME_OUTPUT_DATA (f)->menu_up_to_date_p = 1;
      fset_menu_bar_vector (f, menu_items);
      f->menu_bar_items_used = menu_items_used;
    }
  unbind_to (specpdl_count, Qnil);
}

DEFUN ("menu-or-popup-active-p", Fmenu_or_popup_active_p, Smenu_or_popup_active_p,
       0, 0, 0, doc: /* SKIP: real doc in xmenu.c. */)
  (void)
{
  return popup_activated_p ? Qt : Qnil;
}

void
syms_of_haikumenu (void)
{
  DEFSYM (Qdebug_on_next_call, "debug-on-next-call");

  defsubr (&Smenu_or_popup_active_p);
  return;
}