/**
 * GNT - The GLib Ncurses Toolkit
 *
 * GNT is the legal property of its developers, whose names are too numerous
 * to list here.  Please refer to the COPYRIGHT file distributed with this
 * source distribution.
 *
 * This library 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 2 of the License, or
 * (at your option) any later version.
 *
 * This program 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 this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02111-1301  USA
 */

#include "gntinternal.h"
#include "gntmenu.h"
#include "gntmenuitemcheck.h"

#include <ctype.h>
#include <string.h>

enum
{
	SIGS = 1,
};

enum
{
	ITEM_TEXT = 0,
	ITEM_TRIGGER,
	ITEM_SUBMENU,
	NUM_COLUMNS
};

static GntTreeClass *parent_class = NULL;

static void (*org_draw)(GntWidget *wid);
static void (*org_destroy)(GntWidget *wid);
static void (*org_map)(GntWidget *wid);
static void (*org_size_request)(GntWidget *wid);
static gboolean (*org_key_pressed)(GntWidget *w, const char *t);
static gboolean (*org_clicked)(GntWidget *w, GntMouseEvent event, int x, int y);

static void menuitem_activate(GntMenu *menu, GntMenuItem *item);

static void
menu_hide_all(GntMenu *menu)
{
	while (menu->parentmenu)
		menu = menu->parentmenu;
	gnt_widget_hide(GNT_WIDGET(menu));
}

static void
show_submenu(GntMenu *menu)
{
	GntMenuItem *item;

	if (menu->type != GNT_MENU_TOPLEVEL)
			return;

	item = g_list_nth_data(menu->list, menu->selected);
	if (!item || !item->submenu)
		return;
	menuitem_activate(menu, item);
}

static void
gnt_menu_draw(GntWidget *widget)
{
	GntMenu *menu = GNT_MENU(widget);
	GList *iter;
	chtype type;
	int i;

	if (menu->type == GNT_MENU_TOPLEVEL) {
		wbkgdset(widget->window, '\0' | gnt_color_pair(GNT_COLOR_HIGHLIGHT));
		werase(widget->window);

		for (i = 0, iter = menu->list; iter; iter = iter->next, i++) {
			GntMenuItem *item = GNT_MENU_ITEM(iter->data);
			type = ' ' | gnt_color_pair(GNT_COLOR_HIGHLIGHT);
			if (i == menu->selected)
				type |= A_REVERSE;
			item->priv.x = getcurx(widget->window) + widget->priv.x;
			item->priv.y = getcury(widget->window) + widget->priv.y + 1;
			wbkgdset(widget->window, type);
			wprintw(widget->window, " %s   ", C_(item->text));
		}
	} else {
		org_draw(widget);
	}

	GNTDEBUG;
}

static void
gnt_menu_size_request(GntWidget *widget)
{
	GntMenu *menu = GNT_MENU(widget);

	if (menu->type == GNT_MENU_TOPLEVEL) {
		widget->priv.height = 1;
		widget->priv.width = getmaxx(stdscr);
	} else {
		org_size_request(widget);
		widget->priv.height = g_list_length(menu->list) + 2;
	}
}

static void
menu_tree_add(GntMenu *menu, GntMenuItem *item, GntMenuItem *parent)
{
	char trigger[4] = "\0 )\0";

	if ((trigger[1] = gnt_menuitem_get_trigger(item)) && trigger[1] != ' ')
		trigger[0] = '(';

	if (GNT_IS_MENU_ITEM_CHECK(item)) {
		gnt_tree_add_choice(GNT_TREE(menu), item,
			gnt_tree_create_row(GNT_TREE(menu), item->text, trigger, " "), parent, NULL);
		gnt_tree_set_choice(GNT_TREE(menu), item, gnt_menuitem_check_get_checked(GNT_MENU_ITEM_CHECK(item)));
	} else
		gnt_tree_add_row_last(GNT_TREE(menu), item,
			gnt_tree_create_row(GNT_TREE(menu), item->text, trigger, item->submenu ? ">" : " "), parent);

	if (0 && item->submenu) {
		GntMenu *sub = GNT_MENU(item->submenu);
		GList *iter;
		for (iter = sub->list; iter; iter = iter->next) {
			GntMenuItem *it = GNT_MENU_ITEM(iter->data);
			menu_tree_add(menu, it, item);
		}
	}
}

#define GET_VAL(ch)  ((ch >= '0' && ch <= '9') ? (ch - '0') : (ch >= 'a' && ch <= 'z') ? (10 + ch - 'a') : 36)

static void
assign_triggers(GntMenu *menu)
{
	GList *iter;
	gboolean bools[37];

	memset(bools, 0, sizeof(bools));
	bools[36] = 1;

	for (iter = menu->list; iter; iter = iter->next) {
		GntMenuItem *item = iter->data;
		char trigger = tolower(gnt_menuitem_get_trigger(item));
		if (trigger == '\0' || trigger == ' ')
			continue;
		bools[(int)GET_VAL(trigger)] = 1;
	}

	for (iter = menu->list; iter; iter = iter->next) {
		GntMenuItem *item = iter->data;
		char trigger = gnt_menuitem_get_trigger(item);
		const char *text = item->text;
		if (trigger != '\0')
			continue;
		while (*text) {
			char ch = tolower(*text++);
			char t[2] = {ch, '\0'};
			if (ch == ' ' || bools[(int)GET_VAL(ch)] || gnt_bindable_check_key(GNT_BINDABLE(menu), t))
				continue;
			trigger = ch;
			break;
		}
		if (trigger == 0)
			trigger = item->text[0];
		gnt_menuitem_set_trigger(item, trigger);
		bools[(int)GET_VAL(trigger)] = 1;
	}
}

static void
gnt_menu_map(GntWidget *widget)
{
	GntMenu *menu = GNT_MENU(widget);

	if (menu->type == GNT_MENU_TOPLEVEL) {
		gnt_widget_size_request(widget);
	} else {
		/* Populate the tree */
		GList *iter;
		gnt_tree_remove_all(GNT_TREE(widget));
		/* Try to assign some trigger for the items */
		assign_triggers(menu);
		for (iter = menu->list; iter; iter = iter->next) {
			GntMenuItem *item = GNT_MENU_ITEM(iter->data);
			menu_tree_add(menu, item, NULL);
		}
		org_map(widget);
		gnt_tree_adjust_columns(GNT_TREE(widget));
	}
	GNTDEBUG;
}

static void
menuitem_activate(GntMenu *menu, GntMenuItem *item)
{
	if (!item)
		return;

	if (gnt_menuitem_activate(item)) {
		menu_hide_all(menu);
	} else {
		if (item->submenu) {
			GntMenu *sub = GNT_MENU(item->submenu);
			menu->submenu = sub;
			sub->type = GNT_MENU_POPUP;	/* Submenus are *never* toplevel */
			sub->parentmenu = menu;
			if (menu->type != GNT_MENU_TOPLEVEL) {
				GntWidget *widget = GNT_WIDGET(menu);
				item->priv.x = widget->priv.x + widget->priv.width - 1;
				item->priv.y = widget->priv.y + gnt_tree_get_selection_visible_line(GNT_TREE(menu));
			}
			gnt_widget_set_position(GNT_WIDGET(sub), item->priv.x, item->priv.y);
			GNT_WIDGET_UNSET_FLAGS(GNT_WIDGET(sub), GNT_WIDGET_INVISIBLE);
			gnt_widget_draw(GNT_WIDGET(sub));
		} else {
			menu_hide_all(menu);
		}
	}
}

static GList*
find_item_with_trigger(GList *start, GList *end, char trigger)
{
	GList *iter;
	for (iter = start; iter != (end ? end : NULL); iter = iter->next) {
		if (gnt_menuitem_get_trigger(iter->data) == trigger)
			return iter;
	}
	return NULL;
}

static gboolean
check_for_trigger(GntMenu *menu, char trigger)
{
	/* check for a trigger key */
	GList *iter;
	GList *find;
	GList *nth = g_list_find(menu->list, gnt_tree_get_selection_data(GNT_TREE(menu)));

	if (nth == NULL)
		return FALSE;

	find = find_item_with_trigger(nth->next, NULL, trigger);
	if (!find)
		find = find_item_with_trigger(menu->list, nth->next, trigger);
	if (!find)
		return FALSE;
	if (find != nth) {
		gnt_tree_set_selected(GNT_TREE(menu), find->data);
		iter = find_item_with_trigger(find->next, NULL, trigger);
		if (iter != NULL && iter != find)
			return TRUE;
		iter = find_item_with_trigger(menu->list, nth, trigger);
		if (iter != NULL && iter != find)
			return TRUE;
	}
	gnt_widget_activate(GNT_WIDGET(menu));
	return TRUE;
}

static gboolean
gnt_menu_key_pressed(GntWidget *widget, const char *text)
{
	GntMenu *menu = GNT_MENU(widget);
	int current = menu->selected;

	if (menu->submenu) {
		GntMenu *sub = menu;
		do sub = sub->submenu; while (sub->submenu);
		if (gnt_widget_key_pressed(GNT_WIDGET(sub), text))
			return TRUE;
		if (menu->type != GNT_MENU_TOPLEVEL)
			return FALSE;
	}

	if ((text[0] == 27 && text[1] == 0) ||
			(menu->type != GNT_MENU_TOPLEVEL && strcmp(text, GNT_KEY_LEFT) == 0)) {
		/* Escape closes menu */
		GntMenu *par = menu->parentmenu;
		if (par != NULL) {
			par->submenu = NULL;
			gnt_widget_hide(widget);
		} else
			gnt_widget_hide(widget);
		if (par && par->type == GNT_MENU_TOPLEVEL)
			gnt_menu_key_pressed(GNT_WIDGET(par), text);
		return TRUE;
	}

	if (menu->type == GNT_MENU_TOPLEVEL) {
		if (strcmp(text, GNT_KEY_LEFT) == 0) {
			menu->selected--;
			if (menu->selected < 0)
				menu->selected = g_list_length(menu->list) - 1;
		} else if (strcmp(text, GNT_KEY_RIGHT) == 0) {
			menu->selected++;
			if (menu->selected >= g_list_length(menu->list))
				menu->selected = 0;
		} else if (strcmp(text, GNT_KEY_ENTER) == 0 ||
				strcmp(text, GNT_KEY_DOWN) == 0) {
			gnt_widget_activate(widget);
		}

		if (current != menu->selected) {
			GntMenu *sub = menu->submenu;
			if (sub)
				gnt_widget_hide(GNT_WIDGET(sub));
			show_submenu(menu);
			gnt_widget_draw(widget);
			return TRUE;
		}
	} else {
		if (text[1] == '\0') {
			if (check_for_trigger(menu, text[0]))
				return TRUE;
		} else if (strcmp(text, GNT_KEY_RIGHT) == 0) {
			GntMenuItem *item = gnt_tree_get_selection_data(GNT_TREE(menu));
			if (item && item->submenu) {
				menuitem_activate(menu, item);
				return TRUE;
			}
		}
		if (gnt_bindable_perform_action_key(GNT_BINDABLE(widget), text))
			return TRUE;
		return org_key_pressed(widget, text);
	}

	return gnt_bindable_perform_action_key(GNT_BINDABLE(widget), text);
}

static void
gnt_menu_destroy(GntWidget *widget)
{
	GntMenu *menu = GNT_MENU(widget);
	g_list_foreach(menu->list, (GFunc)g_object_unref, NULL);
	g_list_free(menu->list);
	org_destroy(widget);
}

static void
gnt_menu_toggled(GntTree *tree, gpointer key)
{
	GntMenuItem *item = GNT_MENU_ITEM(key);
	GntMenu *menu = GNT_MENU(tree);
	gboolean check = gnt_menuitem_check_get_checked(GNT_MENU_ITEM_CHECK(item));
	gnt_menuitem_check_set_checked(GNT_MENU_ITEM_CHECK(item), !check);
	gnt_menuitem_activate(item);
	while (menu) {
		gnt_widget_hide(GNT_WIDGET(menu));
		menu = menu->parentmenu;
	}
}

static void
gnt_menu_activate(GntWidget *widget)
{
	GntMenu *menu = GNT_MENU(widget);
	GntMenuItem *item;

	if (menu->type == GNT_MENU_TOPLEVEL) {
		item = g_list_nth_data(menu->list, menu->selected);
	} else {
		item = gnt_tree_get_selection_data(GNT_TREE(menu));
	}

	if (item) {
		if (GNT_IS_MENU_ITEM_CHECK(item))
			gnt_menu_toggled(GNT_TREE(widget), item);
		else
			menuitem_activate(menu, item);
	}
}

static void
gnt_menu_hide(GntWidget *widget)
{
	GntMenu *sub, *menu = GNT_MENU(widget);

	while ((sub = menu->submenu))
		gnt_widget_hide(GNT_WIDGET(sub));
	if (menu->parentmenu)
		menu->parentmenu->submenu = NULL;
}

static gboolean
gnt_menu_clicked(GntWidget *widget, GntMouseEvent event, int x, int y)
{
	if (GNT_MENU(widget)->type != GNT_MENU_POPUP)
		return FALSE;

	if (org_clicked && org_clicked(widget, event, x, y))
		return TRUE;
	gnt_widget_activate(widget);
	return TRUE;
}

static void
gnt_menu_class_init(GntMenuClass *klass)
{
	GntWidgetClass *wid_class = GNT_WIDGET_CLASS(klass);
	parent_class = GNT_TREE_CLASS(klass);

	org_destroy = wid_class->destroy;
	org_map = wid_class->map;
	org_draw = wid_class->draw;
	org_key_pressed = wid_class->key_pressed;
	org_size_request = wid_class->size_request;
	org_clicked = wid_class->clicked;

	wid_class->destroy = gnt_menu_destroy;
	wid_class->draw = gnt_menu_draw;
	wid_class->map = gnt_menu_map;
	wid_class->size_request = gnt_menu_size_request;
	wid_class->key_pressed = gnt_menu_key_pressed;
	wid_class->activate = gnt_menu_activate;
	wid_class->hide = gnt_menu_hide;
	wid_class->clicked = gnt_menu_clicked;

	parent_class->toggled = gnt_menu_toggled;

	GNTDEBUG;
}

static void
gnt_menu_init(GTypeInstance *instance, gpointer class)
{
	GntWidget *widget = GNT_WIDGET(instance);
	GNT_WIDGET_SET_FLAGS(widget, GNT_WIDGET_NO_SHADOW | GNT_WIDGET_NO_BORDER |
			GNT_WIDGET_CAN_TAKE_FOCUS | GNT_WIDGET_TRANSIENT | GNT_WIDGET_DISABLE_ACTIONS);
	GNTDEBUG;
}

/******************************************************************************
 * GntMenu API
 *****************************************************************************/
GType
gnt_menu_get_gtype(void)
{
	static GType type = 0;

	if(type == 0)
	{
		static const GTypeInfo info = {
			sizeof(GntMenuClass),
			NULL,					/* base_init		*/
			NULL,					/* base_finalize	*/
			(GClassInitFunc)gnt_menu_class_init,
			NULL,					/* class_finalize	*/
			NULL,					/* class_data		*/
			sizeof(GntMenu),
			0,						/* n_preallocs		*/
			gnt_menu_init,			/* instance_init	*/
			NULL					/* value_table		*/
		};

		type = g_type_register_static(GNT_TYPE_TREE,
									  "GntMenu",
									  &info, 0);
	}

	return type;
}

GntWidget *gnt_menu_new(GntMenuType type)
{
	GntWidget *widget = g_object_new(GNT_TYPE_MENU, NULL);
	GntMenu *menu = GNT_MENU(widget);
	menu->list = NULL;
	menu->selected = 0;
	menu->type = type;

	if (type == GNT_MENU_TOPLEVEL) {
		widget->priv.x = 0;
		widget->priv.y = 0;
	} else {
		GNT_TREE(widget)->show_separator = FALSE;
		g_object_set(G_OBJECT(widget), "columns", NUM_COLUMNS, NULL);
		gnt_tree_set_col_width(GNT_TREE(widget), ITEM_TRIGGER, 3);
		gnt_tree_set_column_resizable(GNT_TREE(widget), ITEM_TRIGGER, FALSE);
		gnt_tree_set_col_width(GNT_TREE(widget), ITEM_SUBMENU, 1);
		gnt_tree_set_column_resizable(GNT_TREE(widget), ITEM_SUBMENU, FALSE);
		GNT_WIDGET_UNSET_FLAGS(widget, GNT_WIDGET_NO_BORDER);
	}

	return widget;
}

void gnt_menu_add_item(GntMenu *menu, GntMenuItem *item)
{
	menu->list = g_list_append(menu->list, item);
}

GntMenuItem *gnt_menu_get_item(GntMenu *menu, const char *id)
{
	GntMenuItem *item = NULL;
	GList *iter = menu->list;

	if (!id || !*id)
		return NULL;

	for (; iter; iter = iter->next) {
		GntMenu *sub;
		item = iter->data;
		sub = gnt_menuitem_get_submenu(item);
		if (sub) {
			item = gnt_menu_get_item(sub, id);
			if (item)
				break;
		} else {
			const char *itid = gnt_menuitem_get_id(item);
			if (itid && strcmp(itid, id) == 0)
				break;
			/* XXX: Perhaps look at the menu-label as well? */
		}
		item = NULL;
	}

	return item;
}

