/**
 * \file QLPopupMenu.C
 * This file is part of LyX, the document processor.
 * Licence details can be found in the file COPYING.
 *
 * \author John Levon
 *
 * Full author contact details are available in file CREDITS.
 */

#include <config.h>

// Qt defines a macro 'signals' that clashes with a boost namespace.
// All is well if the namespace is visible first.
#include "QtView.h"

#include "QLPopupMenu.h"
#include "QLMenubar.h"
#include "qt_helpers.h"

#include "MenuBackend.h"

#include "support/lstrings.h"

#ifdef Q_WS_MACX
#include "kbmap.h"
#include "QLyXKeySym.h"
extern boost::scoped_ptr<kb_keymap> toplevel_keymap;
#endif

#include <qapplication.h>

using std::distance;
using std::make_pair;
using std::string;
using std::pair;

namespace lyx {

using support::subst;

namespace frontend {

namespace {

string const getLabel(MenuItem const & mi)
{
	string const shortcut = mi.shortcut();
	string label = subst(mi.label(), "&", "&&");

	if (!shortcut.empty()) {
		string::size_type pos = label.find(shortcut);
		if (pos != string::npos)
			label.insert(pos, 1, '&');
	}

	return label;
}

#ifdef Q_WS_MACX
// The offset added to the special Mac menu entries
const int indexOffset = 5000;
#endif

} // namespace anon


pair<int, QLPopupMenu *>
createMenu(QMenuData * parent, MenuItem const * item, QLMenubar * owner,
	   bool is_toplevel)
{
	QLPopupMenu * pm = new QLPopupMenu(owner, item->submenuname(), is_toplevel);
	int const id = parent->insertItem(toqstr(getLabel(*item)), pm);
	return make_pair(id, pm);
}


QLPopupMenu::QLPopupMenu(QLMenubar * owner,
			 string const & name, bool toplevel)
	: owner_(owner), name_(name)
{
	if (toplevel)
		connect(this, SIGNAL(aboutToShow()), this, SLOT(showing()));
	connect(this, SIGNAL(activated(int)),
		this, SLOT(fire(int)));
}


void QLPopupMenu::fire(int index)
{
	qApp->processEvents();
#ifdef Q_WS_MACX
	if (index >= indexOffset) {
		MenuItem mi = owner_->backend().getMenu("LyX")[index - indexOffset];
		owner_->view()->activated(mi.func());
	} else
#endif
		owner_->view()->activated(funcs_[index]);
}


void QLPopupMenu::populate(Menu * menu)
{
	funcs_.clear();

	Menu::const_iterator m = menu->begin();
	Menu::const_iterator end = menu->end();
	for (; m != end; ++m) {
		if (m->kind() == MenuItem::Separator) {
			insertSeparator();
		} else if (m->kind() == MenuItem::Submenu) {
			pair<int, QLPopupMenu *> res = createMenu(this, &(*m), owner_);
			setItemEnabled(res.first, m->status().enabled());
			res.second->populate(m->submenu());
		} else { // we have a MenuItem::Command
			FuncStatus const status = m->status();

			Funcs::iterator fit =
				funcs_.insert(funcs_.end(), m->func());
			int const index = distance(funcs_.begin(), fit);

			QString label = toqstr(getLabel(*m));
#ifdef Q_WS_MACX
			/* There are two constraints on Qt/Mac: (1)
			   the bindings require a unicode string to be
			   represented meaningfully and std::string
			   does not work (2) only 1-key bindings can
			   be represented in menus.
			   
			   This is why the unpleasant hack bellow is
			   needed (JMarc)
			*/
			pair<LyXKeySym const *, key_modifier::state>
				binding = toplevel_keymap->find1keybinding(m->func());
			if (binding.first) {
				QLyXKeySym const *key = static_cast<QLyXKeySym const *>(binding.first);
				label += '\t' + key->qprint(binding.second);
			}
#else
			string const binding(m->binding());
			if (!binding.empty()) {
				label += '\t' + toqstr(binding);
			}
#endif

			// Actually insert the menu item
			insertItem(label, index);
			setItemEnabled(index, status.enabled());
			setItemChecked(index, status.onoff(true));
		}
	}
}


void QLPopupMenu::showing()
{
	clear();
	Menu tomenu;
	Menu const frommenu = owner_->backend().getMenu(name_);
	owner_->backend().expand(frommenu, tomenu, owner_->view());
	populate(&tomenu);
#ifdef Q_WS_MACX
	/* The qt/mac menu code has a very silly hack that
	   moves some menu entries that it recognizes by name
	   (e.g. "Preferences...") to the "LyX" menu. This
	   feature can only work if the menu entries are
	   always available. Since we build menus on demand,
	   we add some dummy contents to one of the menus (JMarc)
	*/
	static QLPopupMenu * themenu = this;
	if (themenu == this && owner_->backend().hasMenu("LyX")) {
		Menu special = owner_->backend().getMenu("LyX");
		Menu::const_iterator end = special.end();
		Menu::size_type i = 0;
		for (Menu::const_iterator cit = special.begin();
		     cit != end ; ++cit, ++i)
			insertItem(toqstr(cit->label()), indexOffset + i);
	}
#endif
}

} // namespace frontend
} // namespace lyx