/*************************************************************************/
/*  tab_container.cpp                                                    */
/*************************************************************************/
/*                       This file is part of:                           */
/*                           GODOT ENGINE                                */
/*                      https://godotengine.org                          */
/*************************************************************************/
/* Copyright (c) 2007-2018 Juan Linietsky, Ariel Manzur.                 */
/* Copyright (c) 2014-2018 Godot Engine contributors (cf. AUTHORS.md)    */
/*                                                                       */
/* Permission is hereby granted, free of charge, to any person obtaining */
/* a copy of this software and associated documentation files (the       */
/* "Software"), to deal in the Software without restriction, including   */
/* without limitation the rights to use, copy, modify, merge, publish,   */
/* distribute, sublicense, and/or sell copies of the Software, and to    */
/* permit persons to whom the Software is furnished to do so, subject to */
/* the following conditions:                                             */
/*                                                                       */
/* The above copyright notice and this permission notice shall be        */
/* included in all copies or substantial portions of the Software.       */
/*                                                                       */
/* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,       */
/* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF    */
/* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.*/
/* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY  */
/* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,  */
/* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE     */
/* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.                */
/*************************************************************************/
#include "tab_container.h"

#include "message_queue.h"

int TabContainer::_get_top_margin() const {

	Ref<StyleBox> tab_bg = get_stylebox("tab_bg");
	Ref<StyleBox> tab_fg = get_stylebox("tab_fg");
	Ref<Font> font = get_font("font");

	int h = MAX(tab_bg->get_minimum_size().height, tab_fg->get_minimum_size().height);

	int ch = font->get_height();
	for (int i = 0; i < get_child_count(); i++) {

		Control *c = get_child(i)->cast_to<Control>();
		if (!c)
			continue;
		if (c->is_set_as_toplevel())
			continue;
		if (!c->has_meta("_tab_icon"))
			continue;

		Ref<Texture> tex = c->get_meta("_tab_icon");
		if (!tex.is_valid())
			continue;
		ch = MAX(ch, tex->get_size().height);
	}

	h += ch;

	return h;
}

void TabContainer::_input_event(const InputEvent &p_event) {

	if (p_event.type == InputEvent::MOUSE_BUTTON &&
			p_event.mouse_button.pressed &&
			p_event.mouse_button.button_index == BUTTON_LEFT) {

		// clicks
		Point2 pos(p_event.mouse_button.x, p_event.mouse_button.y);

		int top_margin = _get_top_margin();
		if (pos.y > top_margin)
			return; // no click (too far down)

		if (pos.x < tabs_ofs_cache)
			return; // no click (too far left)

		Ref<StyleBox> tab_bg = get_stylebox("tab_bg");
		Ref<StyleBox> tab_fg = get_stylebox("tab_fg");
		Ref<Font> font = get_font("font");
		Ref<Texture> incr = get_icon("increment");
		Ref<Texture> decr = get_icon("decrement");
		Ref<Texture> menu = get_icon("menu");
		Ref<Texture> menu_hl = get_icon("menu_hl");

		if (popup && pos.x > get_size().width - menu->get_width()) {

			emit_signal("pre_popup_pressed");
			Vector2 pp_pos = get_global_pos();
			pp_pos.x += get_size().width;
			pp_pos.x -= popup->get_size().width;
			pp_pos.y += menu->get_height();

			popup->set_global_pos(pp_pos);
			popup->popup();
			return;
		}
		pos.x -= tabs_ofs_cache;

		int idx = 0;
		int found = -1;
		bool rightroom = false;

		for (int i = 0; i < get_child_count(); i++) {

			Control *c = get_child(i)->cast_to<Control>();
			if (!c)
				continue;
			if (c->is_set_as_toplevel())
				continue;

			if (idx < tab_display_ofs) {
				idx++;
				continue;
			}

			if (idx > last_tab_cache) {
				rightroom = true;
				break;
			}

			String s = c->has_meta("_tab_name") ? String(XL_MESSAGE(String(c->get_meta("_tab_name")))) : String(c->get_name());
			int tab_width = font->get_string_size(s).width;

			if (c->has_meta("_tab_icon")) {
				Ref<Texture> icon = c->get_meta("_tab_icon");
				if (icon.is_valid()) {
					tab_width += icon->get_width();
					if (s != "")
						tab_width += get_constant("hseparation");
				}
			}

			if (idx == current) {

				tab_width += tab_fg->get_minimum_size().width;
			} else {
				tab_width += tab_bg->get_minimum_size().width;
			}

			if (pos.x < tab_width) {

				found = idx;
				break;
			}

			pos.x -= tab_width;
			idx++;
		}

		if (buttons_visible_cache) {

			if (p_event.mouse_button.x > get_size().width - incr->get_width()) {
				if (rightroom) {
					tab_display_ofs += 1;
					update();
				}
			} else if (p_event.mouse_button.x > get_size().width - incr->get_width() - decr->get_width()) {

				if (tab_display_ofs > 0) {
					tab_display_ofs -= 1;
					update();
				}
			}
		}

		if (found != -1) {

			set_current_tab(found);
		}
	}
}

void TabContainer::_notification(int p_what) {

	switch (p_what) {

		case NOTIFICATION_DRAW: {

			RID ci = get_canvas_item();
			Ref<StyleBox> panel = get_stylebox("panel");
			Size2 size = get_size();

			if (!tabs_visible) {

				panel->draw(ci, Rect2(0, 0, size.width, size.height));
				return;
			}

			Ref<StyleBox> tab_bg = get_stylebox("tab_bg");
			Ref<StyleBox> tab_fg = get_stylebox("tab_fg");
			Ref<Texture> incr = get_icon("increment");
			Ref<Texture> decr = get_icon("decrement");
			Ref<Texture> menu = get_icon("menu");
			Ref<Texture> menu_hl = get_icon("menu_hl");
			Ref<Font> font = get_font("font");
			Color color_fg = get_color("font_color_fg");
			Color color_bg = get_color("font_color_bg");

			int side_margin = get_constant("side_margin");
			int top_margin = _get_top_margin();

			Size2 top_size = Size2(size.width, top_margin);

			int w = 0;
			int idx = 0;
			Vector<int> offsets;
			Vector<Control *> controls;
			int from = 0;
			int limit = get_size().width;
			if (popup) {
				top_size.width -= menu->get_width();
				limit -= menu->get_width();
			}

			bool notdone = false;
			last_tab_cache = -1;

			for (int i = 0; i < get_child_count(); i++) {

				Control *c = get_child(i)->cast_to<Control>();
				if (!c)
					continue;
				if (c->is_set_as_toplevel())
					continue;
				if (idx < tab_display_ofs) {
					idx++;
					from = idx;
					continue;
				}

				if (w >= get_size().width) {
					buttons_visible_cache = true;
					notdone = true;
					break;
				}

				offsets.push_back(w);
				controls.push_back(c);

				String s = c->has_meta("_tab_name") ? String(XL_MESSAGE(String(c->get_meta("_tab_name")))) : String(c->get_name());
				w += font->get_string_size(s).width;
				if (c->has_meta("_tab_icon")) {
					Ref<Texture> icon = c->get_meta("_tab_icon");
					if (icon.is_valid()) {
						w += icon->get_width();
						if (s != "")
							w += get_constant("hseparation");
					}
				}

				if (idx == current) {

					w += tab_fg->get_minimum_size().width;
				} else {
					w += tab_bg->get_minimum_size().width;
				}

				if (idx < tab_display_ofs) {
				}
				last_tab_cache = idx;

				idx++;
			}

			int ofs;

			switch (align) {

				case ALIGN_LEFT: ofs = side_margin; break;
				case ALIGN_CENTER: ofs = (int(limit) - w) / 2; break;
				case ALIGN_RIGHT: ofs = int(limit) - w - side_margin; break;
			};

			tab_display_ofs = 0;

			tabs_ofs_cache = ofs;
			idx = 0;

			for (int i = 0; i < controls.size(); i++) {

				idx = i + from;
				if (current >= from && current < from + controls.size() - 1) {
					//current is visible! draw it last.
					if (i == controls.size() - 1) {
						idx = current;
					} else if (idx >= current) {
						idx += 1;
					}
				}

				Control *c = controls[idx - from];

				String s = c->has_meta("_tab_name") ? String(c->get_meta("_tab_name")) : String(c->get_name());
				int w = font->get_string_size(s).width;
				Ref<Texture> icon;
				if (c->has_meta("_tab_icon")) {
					icon = c->get_meta("_tab_icon");
					if (icon.is_valid()) {

						w += icon->get_width();
						if (s != "")
							w += get_constant("hseparation");
					}
				}

				Ref<StyleBox> sb;
				Color col;

				if (idx == current) {

					sb = tab_fg;
					col = color_fg;
				} else {
					sb = tab_bg;
					col = color_bg;
				}

				int lofs = ofs + offsets[idx - from];

				Size2i sb_ms = sb->get_minimum_size();
				Rect2 sb_rect = Rect2(lofs, 0, w + sb_ms.width, top_margin);

				sb->draw(ci, sb_rect);

				Point2i lpos = sb_rect.pos;
				lpos.x += sb->get_margin(MARGIN_LEFT);
				if (icon.is_valid()) {

					icon->draw(ci, Point2i(lpos.x, sb->get_margin(MARGIN_TOP) + ((sb_rect.size.y - sb_ms.y) - icon->get_height()) / 2));
					if (s != "")
						lpos.x += icon->get_width() + get_constant("hseparation");
				}

				font->draw(ci, Point2i(lpos.x, sb->get_margin(MARGIN_TOP) + ((sb_rect.size.y - sb_ms.y) - font->get_height()) / 2 + font->get_ascent()), s, col);

				idx++;
			}

			if (buttons_visible_cache) {

				int vofs = (top_margin - incr->get_height()) / 2;
				decr->draw(ci, Point2(limit, vofs), Color(1, 1, 1, tab_display_ofs == 0 ? 0.5 : 1.0));
				incr->draw(ci, Point2(limit + incr->get_width(), vofs), Color(1, 1, 1, notdone ? 1.0 : 0.5));
			}

			if (popup) {
				int from = get_size().width - menu->get_width();

				if (mouse_x_cache > from)
					menu_hl->draw(get_canvas_item(), Size2(from, 0));
				else
					menu->draw(get_canvas_item(), Size2(from, 0));
			}

			panel->draw(ci, Rect2(0, top_size.height, size.width, size.height - top_size.height));

		} break;
		case NOTIFICATION_THEME_CHANGED: {
			if (get_tab_count() > 0) {
				call_deferred("set_current_tab", get_current_tab()); //wait until all changed theme
			}
		} break;
	}
}

void TabContainer::_child_renamed_callback() {

	update();
}

void TabContainer::add_child_notify(Node *p_child) {

	Control *c = p_child->cast_to<Control>();
	if (!c)
		return;
	if (c->is_set_as_toplevel())
		return;

	bool first = false;

	if (get_tab_count() != 1)
		c->hide();
	else {
		c->show();
		//call_deferred("set_current_tab",0);
		first = true;
		current = 0;
		previous = 0;
	}
	c->set_area_as_parent_rect();
	if (tabs_visible)
		c->set_margin(MARGIN_TOP, _get_top_margin());
	Ref<StyleBox> sb = get_stylebox("panel");
	for (int i = 0; i < 4; i++)
		c->set_margin(Margin(i), c->get_margin(Margin(i)) + sb->get_margin(Margin(i)));

	update();
	p_child->connect("renamed", this, "_child_renamed_callback");
	if (first)
		emit_signal("tab_changed", current);
}

int TabContainer::get_tab_count() const {

	int count = 0;

	for (int i = 0; i < get_child_count(); i++) {

		Control *c = get_child(i)->cast_to<Control>();
		if (!c)
			continue;
		count++;
	}

	return count;
}

void TabContainer::set_current_tab(int p_current) {

	ERR_FAIL_INDEX(p_current, get_tab_count());

	int pending_previous = current;
	current = p_current;

	int idx = 0;

	Ref<StyleBox> sb = get_stylebox("panel");
	for (int i = 0; i < get_child_count(); i++) {

		Control *c = get_child(i)->cast_to<Control>();
		if (!c)
			continue;
		if (c->is_set_as_toplevel())
			continue;
		if (idx == current) {
			c->show();
			c->set_area_as_parent_rect();
			if (tabs_visible)
				c->set_margin(MARGIN_TOP, _get_top_margin());
			for (int i = 0; i < 4; i++)
				c->set_margin(Margin(i), c->get_margin(Margin(i)) + sb->get_margin(Margin(i)));

		} else
			c->hide();
		idx++;
	}

	_change_notify("current_tab");

	if (pending_previous != current)
		previous = pending_previous;

	emit_signal("tab_selected", current);
	emit_signal("tab_changed", current);

	update();
}

int TabContainer::get_current_tab() const {

	return current;
}

int TabContainer::get_previous_tab() const {

	return previous;
}

Control *TabContainer::get_tab_control(int p_idx) const {

	int idx = 0;

	for (int i = 0; i < get_child_count(); i++) {

		Control *c = get_child(i)->cast_to<Control>();
		if (!c)
			continue;
		if (c->is_set_as_toplevel())
			continue;
		if (idx == p_idx) {
			return c;
		}
		idx++;
	}

	return NULL;
}

Control *TabContainer::get_current_tab_control() const {

	int idx = 0;

	for (int i = 0; i < get_child_count(); i++) {

		Control *c = get_child(i)->cast_to<Control>();
		if (!c)
			continue;
		if (c->is_set_as_toplevel())
			continue;
		if (idx == current) {
			return c;
		}
		idx++;
	}

	return NULL;
}

void TabContainer::remove_child_notify(Node *p_child) {

	int tc = get_tab_count();
	if (current == tc - 1) {
		current--;
		if (current < 0)
			current = 0;
		else {
			call_deferred("set_current_tab", current);
		}
	}

	p_child->disconnect("renamed", this, "_child_renamed_callback");

	update();
}

void TabContainer::set_tab_align(TabAlign p_align) {

	ERR_FAIL_INDEX(p_align, 3);
	align = p_align;
	update();

	_change_notify("tab_align");
}

TabContainer::TabAlign TabContainer::get_tab_align() const {

	return align;
}

void TabContainer::set_tabs_visible(bool p_visibe) {

	if (p_visibe == tabs_visible)
		return;

	tabs_visible = p_visibe;

	for (int i = 0; i < get_child_count(); i++) {

		Control *c = get_child(i)->cast_to<Control>();
		if (!c)
			continue;
		if (p_visibe)
			c->set_margin(MARGIN_TOP, _get_top_margin());
		else
			c->set_margin(MARGIN_TOP, 0);
	}
	update();
}

bool TabContainer::are_tabs_visible() const {

	return tabs_visible;
}

Control *TabContainer::_get_tab(int p_idx) const {

	int idx = 0;

	for (int i = 0; i < get_child_count(); i++) {

		Control *c = get_child(i)->cast_to<Control>();
		if (!c)
			continue;
		if (c->is_set_as_toplevel())
			continue;
		if (idx == p_idx)
			return c;
		idx++;
	}
	return NULL;
}

void TabContainer::set_tab_title(int p_tab, const String &p_title) {

	Control *child = _get_tab(p_tab);
	ERR_FAIL_COND(!child);
	child->set_meta("_tab_name", p_title);
}

String TabContainer::get_tab_title(int p_tab) const {

	Control *child = _get_tab(p_tab);
	ERR_FAIL_COND_V(!child, "");
	if (child->has_meta("_tab_name"))
		return child->get_meta("_tab_name");
	else
		return child->get_name();
}

void TabContainer::set_tab_icon(int p_tab, const Ref<Texture> &p_icon) {

	Control *child = _get_tab(p_tab);
	ERR_FAIL_COND(!child);
	child->set_meta("_tab_icon", p_icon);
}
Ref<Texture> TabContainer::get_tab_icon(int p_tab) const {

	Control *child = _get_tab(p_tab);
	ERR_FAIL_COND_V(!child, Ref<Texture>());
	if (child->has_meta("_tab_icon"))
		return child->get_meta("_tab_icon");
	else
		return Ref<Texture>();
}

void TabContainer::get_translatable_strings(List<String> *p_strings) const {

	for (int i = 0; i < get_child_count(); i++) {

		Control *c = get_child(i)->cast_to<Control>();
		if (!c)
			continue;
		if (c->is_set_as_toplevel())
			continue;

		if (!c->has_meta("_tab_name"))
			continue;

		String name = c->get_meta("_tab_name");

		if (name != "")
			p_strings->push_back(name);
	}
}

Size2 TabContainer::get_minimum_size() const {

	Size2 ms;

	for (int i = 0; i < get_child_count(); i++) {

		Control *c = get_child(i)->cast_to<Control>();
		if (!c)
			continue;
		if (c->is_set_as_toplevel())
			continue;

		if (!c->is_visible())
			continue;

		Size2 cms = c->get_combined_minimum_size();
		ms.x = MAX(ms.x, cms.x);
		ms.y = MAX(ms.y, cms.y);
	}

	Ref<StyleBox> tab_bg = get_stylebox("tab_bg");
	Ref<StyleBox> tab_fg = get_stylebox("tab_fg");
	Ref<Font> font = get_font("font");

	ms.y += MAX(tab_bg->get_minimum_size().y, tab_fg->get_minimum_size().y);
	ms.y += font->get_height();

	Ref<StyleBox> sb = get_stylebox("panel");
	ms += sb->get_minimum_size();

	return ms;
}

void TabContainer::set_popup(Node *p_popup) {
	ERR_FAIL_NULL(p_popup);
	popup = p_popup->cast_to<Popup>();
	update();
}

Popup *TabContainer::get_popup() const {
	return popup;
}

void TabContainer::_bind_methods() {

	ObjectTypeDB::bind_method(_MD("_input_event"), &TabContainer::_input_event);
	ObjectTypeDB::bind_method(_MD("get_tab_count"), &TabContainer::get_tab_count);
	ObjectTypeDB::bind_method(_MD("set_current_tab", "tab_idx"), &TabContainer::set_current_tab);
	ObjectTypeDB::bind_method(_MD("get_current_tab"), &TabContainer::get_current_tab);
	ObjectTypeDB::bind_method(_MD("get_previous_tab"), &TabContainer::get_previous_tab);
	ObjectTypeDB::bind_method(_MD("get_current_tab_control:Control"), &TabContainer::get_current_tab_control);
	ObjectTypeDB::bind_method(_MD("get_tab_control:Control", "idx"), &TabContainer::get_tab_control);
	ObjectTypeDB::bind_method(_MD("set_tab_align", "align"), &TabContainer::set_tab_align);
	ObjectTypeDB::bind_method(_MD("get_tab_align"), &TabContainer::get_tab_align);
	ObjectTypeDB::bind_method(_MD("set_tabs_visible", "visible"), &TabContainer::set_tabs_visible);
	ObjectTypeDB::bind_method(_MD("are_tabs_visible"), &TabContainer::are_tabs_visible);
	ObjectTypeDB::bind_method(_MD("set_tab_title", "tab_idx", "title"), &TabContainer::set_tab_title);
	ObjectTypeDB::bind_method(_MD("get_tab_title", "tab_idx"), &TabContainer::get_tab_title);
	ObjectTypeDB::bind_method(_MD("set_tab_icon", "tab_idx", "icon:Texture"), &TabContainer::set_tab_icon);
	ObjectTypeDB::bind_method(_MD("get_tab_icon:Texture", "tab_idx"), &TabContainer::get_tab_icon);
	ObjectTypeDB::bind_method(_MD("set_popup", "popup:Popup"), &TabContainer::set_popup);
	ObjectTypeDB::bind_method(_MD("get_popup:Popup"), &TabContainer::get_popup);

	ObjectTypeDB::bind_method(_MD("_child_renamed_callback"), &TabContainer::_child_renamed_callback);

	ADD_SIGNAL(MethodInfo("tab_changed", PropertyInfo(Variant::INT, "tab")));
	ADD_SIGNAL(MethodInfo("tab_selected", PropertyInfo(Variant::INT, "tab")));
	ADD_SIGNAL(MethodInfo("pre_popup_pressed"));

	ADD_PROPERTY(PropertyInfo(Variant::INT, "tab_align", PROPERTY_HINT_ENUM, "Left,Center,Right"), _SCS("set_tab_align"), _SCS("get_tab_align"));
	ADD_PROPERTY(PropertyInfo(Variant::INT, "current_tab", PROPERTY_HINT_RANGE, "-1,4096,1", PROPERTY_USAGE_EDITOR), _SCS("set_current_tab"), _SCS("get_current_tab"));
	ADD_PROPERTY(PropertyInfo(Variant::BOOL, "tabs_visible"), _SCS("set_tabs_visible"), _SCS("are_tabs_visible"));
}

TabContainer::TabContainer() {

	tab_display_ofs = 0;
	buttons_visible_cache = false;
	tabs_ofs_cache = 0;
	current = 0;
	previous = 0;
	mouse_x_cache = 0;
	align = ALIGN_CENTER;
	tabs_visible = true;
	popup = NULL;
}