/*************************************************************************/
/*  tabs.cpp                                                             */
/*************************************************************************/
/*                       This file is part of:                           */
/*                           GODOT ENGINE                                */
/*                    http://www.godotengine.org                         */
/*************************************************************************/
/* Copyright (c) 2007-2017 Juan Linietsky, Ariel Manzur.                 */
/*                                                                       */
/* 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 "tabs.h"

#include "message_queue.h"

Size2 Tabs::get_minimum_size() const {

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

	Size2 ms(0, MAX(tab_bg->get_minimum_size().height, tab_fg->get_minimum_size().height)+font->get_height());

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

		Ref<Texture> tex = tabs[i].icon;
		if (tex.is_valid()) {
			ms.height = MAX(ms.height, tex->get_size().height);
			if (tabs[i].text!="")
				ms.width+=get_constant("hseparation");
		}

		ms.width+=font->get_string_size(tabs[i].text).width;

		if (current==i)
			ms.width+=tab_fg->get_minimum_size().width;
		else
			ms.width+=tab_bg->get_minimum_size().width;

		if (tabs[i].right_button.is_valid()) {
			Ref<Texture> rb=tabs[i].right_button;
			Size2 bms = rb->get_size();
			bms.width+=get_constant("hseparation");
			ms.width+=bms.width;
			ms.height=MAX(bms.height+tab_bg->get_minimum_size().height,ms.height);
		}

		if (cb_displaypolicy==CLOSE_BUTTON_SHOW_ALWAYS || (cb_displaypolicy==CLOSE_BUTTON_SHOW_ACTIVE_ONLY && i==current)) {
			Ref<Texture> cb=get_icon("close");
			Size2 bms = cb->get_size();
			bms.width+=get_constant("hseparation");
			ms.width+=bms.width;
			ms.height=MAX(bms.height+tab_bg->get_minimum_size().height,ms.height);
		}
	}

	ms.width=0; //TODO: should make this optional
	return ms;
}


void Tabs::_gui_input(const InputEvent& p_event) {

	if (p_event.type==InputEvent::MOUSE_MOTION) {

		Point2 pos( p_event.mouse_motion.x, p_event.mouse_motion.y );

		hilite_arrow=-1;
		if (buttons_visible) {

			Ref<Texture> incr = get_icon("increment");
			Ref<Texture> decr = get_icon("decrement");

			int limit=get_size().width-incr->get_width()-decr->get_width();

			if (pos.x>limit+decr->get_width()) {
				hilite_arrow=1;
			} else if (pos.x>limit) {
				hilite_arrow=0;
			}
		}

		// test hovering to display right or close button
		int hover_buttons=-1;
		hover=-1;
		for(int i=0;i<tabs.size();i++) {

			if (i<offset)
				continue;

			if (tabs[i].rb_rect.has_point(pos)) {
				rb_hover=i;
				cb_hover=-1;
				hover_buttons = i;
				break;
			}
			else if (tabs[i].cb_rect.has_point(pos)) {
				cb_hover=i;
				rb_hover=-1;
				hover_buttons = i;
				break;
			}

		}

		if (hover_buttons == -1) { // no hover
			rb_hover= hover_buttons;
			cb_hover= hover_buttons;
		}
		update();

		return;
	}


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

		if (rb_hover!=-1) {
			//pressed
			emit_signal("right_button_pressed",rb_hover);
		}

		rb_pressing=false;
		update();
	}


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

		if (cb_hover!=-1) {
			//pressed
			emit_signal("tab_close",cb_hover);
		}

		cb_pressing=false;
		update();
	}


	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 );

		if (buttons_visible) {

			Ref<Texture> incr = get_icon("increment");
			Ref<Texture> decr = get_icon("decrement");

			int limit=get_size().width-incr->get_width()-decr->get_width();

			if (pos.x>limit+decr->get_width()) {
				if (missing_right) {
					offset++;
					update();
				}
				return;
			} else if (pos.x>limit) {
				if (offset>0) {
					offset--;
					update();
				}
				return;
			}
		}

		int found=-1;
		for(int i=0;i<tabs.size();i++) {

			if (i<offset)
				continue;

			if (tabs[i].rb_rect.has_point(pos)) {
				rb_pressing=true;
				update();
				return;
			}

			if (tabs[i].cb_rect.has_point(pos)) {
				cb_pressing=true;
				update();
				return;
			}

			if (pos.x >=tabs[i].ofs_cache && pos.x<tabs[i].ofs_cache+tabs[i].size_cache) {
				found=i;
				break;
			}
		}


		if (found!=-1) {

			set_current_tab(found);
			emit_signal("tab_changed",found);
		}
	}

}


void Tabs::_notification(int p_what) {

	switch(p_what) {

		case NOTIFICATION_MOUSE_EXIT: {
			rb_hover=-1;
			cb_hover=-1;
			hover=-1;
			update();
		} break;
		case NOTIFICATION_RESIZED: {

			_ensure_no_over_offset();
		} break;
		case NOTIFICATION_DRAW: {

			RID ci = get_canvas_item();

			Ref<StyleBox> tab_bg = get_stylebox("tab_bg");
			Ref<StyleBox> tab_fg = get_stylebox("tab_fg");
			Ref<Font> font = get_font("font");
			Color color_fg = get_color("font_color_fg");
			Color color_bg = get_color("font_color_bg");
			Ref<Texture> close=get_icon("close");

			int h = get_size().height;
			int w = 0;
			int mw = 0;

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

				tabs[i].ofs_cache = mw;
				mw += get_tab_width(i);
			}


			if (tab_align==ALIGN_CENTER) {
				w=(get_size().width-mw)/2;
			} else if (tab_align==ALIGN_RIGHT) {
				w=get_size().width-mw;
			}

			if (w<0) {
				w=0;
			}

			Ref<Texture> incr = get_icon("increment");
			Ref<Texture> decr = get_icon("decrement");
			Ref<Texture> incr_hl = get_icon("increment_hilite");
			Ref<Texture> decr_hl = get_icon("decrement_hilite");

			int limit=get_size().width - incr->get_size().width - decr->get_size().width;

			missing_right=false;

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

				if (i<offset)
					continue;

				tabs[i].ofs_cache=w;

				int lsize = get_tab_width(i);

				String text = tabs[i].text;
				int slen = font->get_string_size(text).width;

				if (w+lsize > limit) {
					max_drawn_tab=i-1;
					missing_right=true;
					break;
				} else {
					max_drawn_tab=i;
				}


				Ref<StyleBox> sb;
				Color col;

				if (i==current) {
					sb=tab_fg;
					col=color_fg;
				} else {
					sb=tab_bg;
					col=color_bg;
				}


				Rect2 sb_rect = Rect2(w, 0, lsize, h);
				sb->draw(ci, sb_rect);

				w+=sb->get_margin(MARGIN_LEFT);

				Size2i sb_ms = sb->get_minimum_size();
				Ref<Texture> icon = tabs[i].icon;
				if (icon.is_valid()) {

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

				}

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

				w+=slen;

				if (tabs[i].right_button.is_valid()) {

					Ref<StyleBox> style = get_stylebox("button");
					Ref<Texture> rb=tabs[i].right_button;

					w+=get_constant("hseparation");

					Rect2 rb_rect;
					rb_rect.size=style->get_minimum_size()+rb->get_size();
					rb_rect.pos.x=w;
					rb_rect.pos.y=sb->get_margin(MARGIN_TOP)+((sb_rect.size.y-sb_ms.y)-(rb_rect.size.y))/2;

					if (rb_hover==i) {
						if (rb_pressing)
							get_stylebox("button_pressed")->draw(ci,rb_rect);
						else
							style->draw(ci,rb_rect);
					}

					rb->draw(ci,Point2i( w+style->get_margin(MARGIN_LEFT), rb_rect.pos.y+style->get_margin(MARGIN_TOP) ));
					w+=rb->get_width();
					tabs[i].rb_rect=rb_rect;

				}

				if (cb_displaypolicy==CLOSE_BUTTON_SHOW_ALWAYS || (cb_displaypolicy==CLOSE_BUTTON_SHOW_ACTIVE_ONLY && i==current)) {

					Ref<StyleBox> style = get_stylebox("button");
					Ref<Texture> cb=close;

					w+=get_constant("hseparation");

					Rect2 cb_rect;
					cb_rect.size=style->get_minimum_size()+cb->get_size();
					cb_rect.pos.x=w;
					cb_rect.pos.y=sb->get_margin(MARGIN_TOP)+((sb_rect.size.y-sb_ms.y)-(cb_rect.size.y))/2;

					if (cb_hover==i) {
						if (cb_pressing)
							get_stylebox("button_pressed")->draw(ci,cb_rect);
						else
							style->draw(ci,cb_rect);
					}

					cb->draw(ci,Point2i( w+style->get_margin(MARGIN_LEFT), cb_rect.pos.y+style->get_margin(MARGIN_TOP) ));
					w+=cb->get_width();
					tabs[i].cb_rect=cb_rect;
				}

				w+=sb->get_margin(MARGIN_RIGHT);

				tabs[i].size_cache=w-tabs[i].ofs_cache;

			}

			if (offset>0 || missing_right) {

				int vofs = (get_size().height-incr->get_size().height)/2;

				if (offset>0)
					draw_texture(hilite_arrow==0 ? decr_hl : decr, Point2(limit,vofs));
				else
					draw_texture(decr,Point2(limit,vofs), Color(1,1,1,0.5));

				if (missing_right)
					draw_texture(hilite_arrow==1 ? incr_hl : incr, Point2(limit+decr->get_size().width,vofs));
				else
					draw_texture(incr,Point2(limit+decr->get_size().width,vofs), Color(1,1,1,0.5));

				buttons_visible=true;
			} else {
				buttons_visible=false;
			}

		} break;
	}
}

int Tabs::get_tab_count() const {

	return tabs.size();
}


void Tabs::set_current_tab(int p_current) {

	ERR_FAIL_INDEX( p_current, get_tab_count() );

	current=p_current;

	_change_notify("current_tab");
	update();
}

int Tabs::get_current_tab() const {

	return current;
}


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

	ERR_FAIL_INDEX(p_tab,tabs.size());
	tabs[p_tab].text=p_title;
	update();
	minimum_size_changed();

}

String Tabs::get_tab_title(int p_tab) const{

	ERR_FAIL_INDEX_V(p_tab,tabs.size(),"");
	return tabs[p_tab].text;

}


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

	ERR_FAIL_INDEX(p_tab,tabs.size());
	tabs[p_tab].icon=p_icon;
	update();
	minimum_size_changed();

}

Ref<Texture> Tabs::get_tab_icon(int p_tab) const{

	ERR_FAIL_INDEX_V(p_tab,tabs.size(),Ref<Texture>());
	return tabs[p_tab].icon;

}


void Tabs::set_tab_right_button(int p_tab,const Ref<Texture>& p_right_button){

	ERR_FAIL_INDEX(p_tab,tabs.size());
	tabs[p_tab].right_button=p_right_button;
	update();
	minimum_size_changed();

}
Ref<Texture> Tabs::get_tab_right_button(int p_tab) const{

	ERR_FAIL_INDEX_V(p_tab,tabs.size(),Ref<Texture>());
	return tabs[p_tab].right_button;

}


void Tabs::add_tab(const String& p_str,const Ref<Texture>& p_icon) {

	Tab t;
	t.text=p_str;
	t.icon=p_icon;

	tabs.push_back(t);

	update();
	minimum_size_changed();

}

void Tabs::clear_tabs() {
	tabs.clear();
	current=0;
	update();
}

void Tabs::remove_tab(int p_idx) {

	ERR_FAIL_INDEX(p_idx,tabs.size());
	tabs.remove(p_idx);
	if (current>=p_idx)
		current--;
	update();
	minimum_size_changed();

	if (current<0)
		current=0;
	if (current>=tabs.size())
		current=tabs.size()-1;

	_ensure_no_over_offset();

}


void Tabs::set_tab_align(TabAlign p_align) {

	tab_align=p_align;
	update();
}

Tabs::TabAlign Tabs::get_tab_align() const {

	return tab_align;
}

int Tabs::get_tab_width(int p_idx) const {

	ERR_FAIL_INDEX_V(p_idx,tabs.size(),0);

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


	int x=0;

	Ref<Texture> tex = tabs[p_idx].icon;
	if (tex.is_valid()) {
		x+=tex->get_width();
		if (tabs[p_idx].text!="")
			x+=get_constant("hseparation");

	}

	x+=font->get_string_size(tabs[p_idx].text).width;

	if (current==p_idx)
		x+=tab_fg->get_minimum_size().width;
	else
		x+=tab_bg->get_minimum_size().width;

	if (tabs[p_idx].right_button.is_valid()) {
		Ref<Texture> rb=tabs[p_idx].right_button;
		x+=rb->get_width();
		x+=get_constant("hseparation");
	}

	if (cb_displaypolicy==CLOSE_BUTTON_SHOW_ALWAYS || (cb_displaypolicy==CLOSE_BUTTON_SHOW_ACTIVE_ONLY && p_idx==current)) {
		Ref<Texture> cb=get_icon("close");
		x+=cb->get_width();
		x+=get_constant("hseparation");
	}

	return x;
}


void Tabs::_ensure_no_over_offset() {

	if (!is_inside_tree())
		return;

	Ref<Texture> incr = get_icon("increment");
	Ref<Texture> decr = get_icon("decrement");

	int limit=get_size().width-incr->get_width()-decr->get_width();

	while(offset>0) {

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

			if (i<offset-1)
				continue;

			total_w+=get_tab_width(i);
		}

		if (total_w < limit) {
			offset--;
			update();
		} else {
			break;
		}
	}

}


void Tabs::ensure_tab_visible(int p_idx) {

	if (!is_inside_tree())
		return;

	ERR_FAIL_INDEX(p_idx,tabs.size());

	_ensure_no_over_offset();

	if (p_idx<=offset) {
		offset=p_idx;
		update();
		return;
	}

	Ref<Texture> incr = get_icon("increment");
	Ref<Texture> decr = get_icon("decrement");
	int limit=get_size().width-incr->get_width()-decr->get_width();


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

		if (i<offset)
			continue;

		int sz = get_tab_width(i);
		tabs[i].x_cache=x;
		tabs[i].x_size_cache=sz;
		x+=sz;

	}

	while(offset<tabs.size() && ( (tabs[p_idx].x_cache + tabs[p_idx].x_size_cache) - tabs[offset].x_cache) > limit) {
		offset++;
	}

	update();
}

void Tabs::set_tab_close_display_policy(CloseButtonDisplayPolicy p_policy) {
	cb_displaypolicy=p_policy;
	update();
}

void Tabs::_bind_methods() {

	ClassDB::bind_method(_MD("_gui_input"),&Tabs::_gui_input);
	ClassDB::bind_method(_MD("get_tab_count"),&Tabs::get_tab_count);
	ClassDB::bind_method(_MD("set_current_tab","tab_idx"),&Tabs::set_current_tab);
	ClassDB::bind_method(_MD("get_current_tab"),&Tabs::get_current_tab);
	ClassDB::bind_method(_MD("set_tab_title","tab_idx","title"),&Tabs::set_tab_title);
	ClassDB::bind_method(_MD("get_tab_title","tab_idx"),&Tabs::get_tab_title);
	ClassDB::bind_method(_MD("set_tab_icon","tab_idx","icon:Texture"),&Tabs::set_tab_icon);
	ClassDB::bind_method(_MD("get_tab_icon:Texture","tab_idx"),&Tabs::get_tab_icon);
	ClassDB::bind_method(_MD("remove_tab","tab_idx"),&Tabs::remove_tab);
	ClassDB::bind_method(_MD("add_tab","title","icon:Texture"),&Tabs::add_tab);
	ClassDB::bind_method(_MD("set_tab_align","align"),&Tabs::set_tab_align);
	ClassDB::bind_method(_MD("get_tab_align"),&Tabs::get_tab_align);
	ClassDB::bind_method(_MD("ensure_tab_visible","idx"),&Tabs::ensure_tab_visible);

	ADD_SIGNAL(MethodInfo("tab_changed",PropertyInfo(Variant::INT,"tab")));
	ADD_SIGNAL(MethodInfo("right_button_pressed",PropertyInfo(Variant::INT,"tab")));
	ADD_SIGNAL(MethodInfo("tab_close",PropertyInfo(Variant::INT,"tab")));

	ADD_PROPERTY( PropertyInfo(Variant::INT, "current_tab", PROPERTY_HINT_RANGE,"-1,4096,1",PROPERTY_USAGE_EDITOR), "set_current_tab", "get_current_tab") ;

	BIND_CONSTANT( ALIGN_LEFT );
	BIND_CONSTANT( ALIGN_CENTER );
	BIND_CONSTANT( ALIGN_RIGHT );

	BIND_CONSTANT( CLOSE_BUTTON_SHOW_ACTIVE_ONLY );
	BIND_CONSTANT( CLOSE_BUTTON_SHOW_ALWAYS );
	BIND_CONSTANT( CLOSE_BUTTON_SHOW_NEVER );

}


Tabs::Tabs() {

	current=0;
	tab_align=ALIGN_CENTER;
	rb_hover=-1;
	rb_pressing=false;
	hilite_arrow=-1;

	cb_hover=-1;
	cb_pressing=false;
	cb_displaypolicy = CLOSE_BUTTON_SHOW_NEVER;
	offset=0;
	max_drawn_tab=0;

}