/*************************************************************************/
/*  scroll_bar.cpp                                                       */
/*************************************************************************/
/*                       This file is part of:                           */
/*                           GODOT ENGINE                                */
/*                    http://www.godotengine.org                         */
/*************************************************************************/
/* Copyright (c) 2007-2014 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 "scroll_bar.h"
#include "os/keyboard.h"
#include "print_string.h"

bool ScrollBar::focus_by_default=false;



void ScrollBar::set_can_focus_by_default(bool p_can_focus) {
	
	focus_by_default=p_can_focus;
}

void ScrollBar::_input_event(InputEvent p_event) {


	switch(p_event.type) {
	
		case InputEvent::MOUSE_BUTTON: {
	
			const InputEventMouseButton &b=p_event.mouse_button;
			accept_event();

			if (b.button_index==5 && b.pressed) {
		
				if (orientation==VERTICAL)
					set_val( get_val() + get_page() / 4.0 );
				else
					set_val( get_val() + get_page() / 4.0 );
				accept_event();

			}
			
			if (b.button_index==4 && b.pressed) {
		
				if (orientation==HORIZONTAL)
					set_val( get_val() - get_page() / 4.0 );
				else
					set_val( get_val() - get_page() / 4.0  );
				accept_event();
			}
		
			if (b.button_index!=1)
				return;


			if (b.pressed) {


				double ofs = orientation==VERTICAL ? b.y : b.x ;
				Ref<Texture> decr = get_icon("decrement");
				Ref<Texture> incr = get_icon("increment");
				
				double decr_size = orientation==VERTICAL ? decr->get_height() : decr->get_width();
				double incr_size = orientation==VERTICAL ? incr->get_height() : incr->get_width();
				double grabber_ofs = get_grabber_offset();
				double grabber_size = get_grabber_size();
				double total = orientation==VERTICAL ? get_size().height : get_size().width;
				
				if (ofs < decr_size ) {
				
					set_val( get_val() - (custom_step>=0?custom_step:get_step()) );
					break;
				}
				
				if (ofs > total-incr_size ) {
				
					set_val( get_val() + (custom_step>=0?custom_step:get_step()) );
					break;
				}
				
				ofs-=decr_size;
				
				if ( ofs < grabber_ofs ) {
					
					set_val( get_val() - get_page() );
					break;
					
				} 
				
				ofs-=grabber_ofs;
				
				if (ofs < grabber_size ) {
					
					drag.active=true;
					drag.pos_at_click=grabber_ofs+ofs;
					drag.value_at_click=get_unit_value();					
					update();
				} else {
				
				
					set_val( get_val() + get_page() );
				}
				
				
			} else {
		
				drag.active=false;
				update();
			}
			
		} break;
		case InputEvent::MOUSE_MOTION: {
		
			const InputEventMouseMotion &m=p_event.mouse_motion;

			accept_event();

			
			if (drag.active) {
			
				double ofs = orientation==VERTICAL ? m.y : m.x ;
				Ref<Texture> decr = get_icon("decrement");
				
				double decr_size = orientation==VERTICAL ? decr->get_height() : decr->get_width();
				ofs-=decr_size;
				
				double diff = (ofs-drag.pos_at_click) / get_area_size();

				set_unit_value( drag.value_at_click + diff );			
			} else {
			
		
				double ofs = orientation==VERTICAL ? m.y : m.x ;
				Ref<Texture> decr = get_icon("decrement");
				Ref<Texture> incr = get_icon("increment");
				
				double decr_size = orientation==VERTICAL ? decr->get_height() : decr->get_width();
				double incr_size = orientation==VERTICAL ? incr->get_height() : incr->get_width();
				double total = orientation==VERTICAL ? get_size().height : get_size().width;
				
				HiliteStatus new_hilite;
				
				if (ofs < decr_size ) {
				
					new_hilite=HILITE_DECR;
					
				} else if (ofs > total-incr_size ) {
				
					new_hilite=HILITE_INCR;
					
				} else {
				
					new_hilite=HILITE_RANGE;
				}
				
				if (new_hilite!=hilite) {
				
					hilite=new_hilite;
					update();
					
				}
				
			}
		} break;
		case InputEvent::KEY: {
					
			const InputEventKey &k=p_event.key;
		
			if (!k.pressed)
				return;
				
			switch (k.scancode) {
					
				case KEY_LEFT: {
					
					if (orientation!=HORIZONTAL)
						return;
					set_val( get_val() - (custom_step>=0?custom_step:get_step()) );
					
				} break;
				case KEY_RIGHT: {
					
					if (orientation!=HORIZONTAL)
						return;
					set_val( get_val() + (custom_step>=0?custom_step:get_step()) );
					
				} break;
				case KEY_UP: {
					
					if (orientation!=VERTICAL)
						return;
					
					set_val( get_val() - (custom_step>=0?custom_step:get_step()) );
					
					
				} break;
				case KEY_DOWN: {
					
					if (orientation!=VERTICAL)
						return;
					set_val( get_val() + (custom_step>=0?custom_step:get_step()) );
					
				} break;
				case KEY_HOME: {
					
					set_val( get_min() );
					
				} break;
				case KEY_END: {
					
					set_val( get_max() );
					
				} break;
					
			} break;
		}		
	}
}

void ScrollBar::_notification(int p_what) {
	
	if (p_what==NOTIFICATION_DRAW) {
		
		RID ci = get_canvas_item();
		
		Ref<Texture> decr = hilite==HILITE_DECR ? get_icon("decrement_hilite") : get_icon("decrement");
		Ref<Texture> incr = hilite==HILITE_INCR ? get_icon("increment_hilite") : get_icon("increment");
		Ref<StyleBox> bg = has_focus() ? get_stylebox("scroll_focus") : get_stylebox("scroll");
		Ref<StyleBox> grabber = (drag.active || hilite==HILITE_RANGE) ? get_stylebox("grabber_hilite") : get_stylebox("grabber");
		
		Point2 ofs;
		
		VisualServer *vs = VisualServer::get_singleton();

		vs->canvas_item_add_texture_rect( ci, Rect2( Point2(), decr->get_size()),decr->get_rid() );

		if (orientation==HORIZONTAL)
			ofs.x+=decr->get_width();
		else
			ofs.y+=decr->get_height();

		Size2 area=get_size();

		if (orientation==HORIZONTAL)
			area.width-=incr->get_width()+decr->get_width();
		else
			area.height-=incr->get_height()+decr->get_height();

		bg->draw(ci,Rect2(ofs,area));
		
		if (orientation==HORIZONTAL) 
			ofs.width+=area.width;
		else
			ofs.height+=area.height;

		vs->canvas_item_add_texture_rect( ci, Rect2( ofs, decr->get_size()),incr->get_rid() );
		Rect2 grabber_rect;
		
		if (orientation==HORIZONTAL) {
			
			grabber_rect.size.width=get_grabber_size();
			grabber_rect.size.height=get_size().height;
			grabber_rect.pos.y=0;
			grabber_rect.pos.x=get_grabber_offset()+decr->get_width()+bg->get_margin( MARGIN_LEFT );
		} else {
			
			grabber_rect.size.width=get_size().width;
			grabber_rect.size.height=get_grabber_size();
			grabber_rect.pos.y=get_grabber_offset()+decr->get_height()+bg->get_margin( MARGIN_TOP );
			grabber_rect.pos.x=0;			
		}
		
		grabber->draw(ci,grabber_rect);
		
	}
	
	if (p_what==NOTIFICATION_MOUSE_EXIT) {
	
		hilite=HILITE_NONE;
		update();
	}
}

double ScrollBar::get_grabber_min_size() const {
	
	Ref<StyleBox> grabber=get_stylebox("grabber");
	Size2 gminsize=grabber->get_minimum_size()+grabber->get_center_size();
	return (orientation==VERTICAL)?gminsize.height:gminsize.width;	
}

double ScrollBar::get_grabber_size() const {
	
	float range = get_max()-get_min();
	if (range<=0)
		return 0;
	
	float page = (get_page()>0)? get_page() : 0;
//	if (grabber_range < get_step())
//		grabber_range=get_step();
	
	double area_size=get_area_size();
	double grabber_size = page / range * area_size;
	return grabber_size+get_grabber_min_size();
	
}	

double ScrollBar::get_area_size() const {
	
	if (orientation==VERTICAL) {
		
		double area=get_size().height;
		area-=get_stylebox("scroll")->get_minimum_size().height;
		area-=get_icon("increment")->get_height();
		area-=get_icon("decrement")->get_height();
		area-=get_grabber_min_size();
		return area;
		
	} else if (orientation==HORIZONTAL) {
		
		double area=get_size().width;
		area-=get_stylebox("scroll")->get_minimum_size().width;
		area-=get_icon("increment")->get_width();
		area-=get_icon("decrement")->get_width();
		area-=get_grabber_min_size();
		return area;
	} else {
		
		return 0;
	}
	
}

double ScrollBar::get_area_offset() const {
	
	double ofs=0;
	
	if (orientation==VERTICAL) {
		
		ofs+=get_stylebox("hscroll")->get_margin( MARGIN_TOP );
		ofs+=get_icon("decrement")->get_height();

	}	
	
	if (orientation==HORIZONTAL) {
		
		ofs+=get_stylebox("hscroll")->get_margin( MARGIN_LEFT );
		ofs+=get_icon("decrement")->get_width();
	}
	
	return ofs;	
}

double ScrollBar::get_click_pos(const Point2& p_pos) const {
	
	
	float pos=(orientation==VERTICAL)?p_pos.y:p_pos.x;
	pos-=get_area_offset();
	
	float area=get_area_size();
	if (area==0)
		return 0;
	else
		return pos/area;

}

double ScrollBar::get_grabber_offset() const {
	
	
	return (get_area_size()) * get_unit_value();

}



Size2 ScrollBar::get_minimum_size() const {
	
	Ref<Texture> incr = get_icon("increment");
	Ref<Texture> decr = get_icon("decrement");
	Ref<StyleBox> bg = get_stylebox("scroll");
	Size2 minsize;
	
	if (orientation==VERTICAL) {
	
		minsize.width=MAX(incr->get_size().width,(bg->get_minimum_size()+bg->get_center_size()).width);
		minsize.height+=incr->get_size().height;
		minsize.height+=decr->get_size().height;
		minsize.height+=bg->get_minimum_size().height;
		minsize.height+=get_grabber_min_size();
	}
		
	if (orientation==HORIZONTAL) {
		
		minsize.height=MAX(incr->get_size().height,(bg->get_center_size()+bg->get_minimum_size()).height);
		minsize.width+=incr->get_size().width;
		minsize.width+=decr->get_size().width;
		minsize.width+=bg->get_minimum_size().width;
		minsize.width+=get_grabber_min_size();
	}
	
	return minsize;

}

void ScrollBar::set_custom_step(float p_custom_step) {

	custom_step=p_custom_step;
}

float ScrollBar::get_custom_step() const {

	return custom_step;
}


#if 0

void ScrollBar::mouse_button(const Point2& p_pos, int b.button_index,bool b.pressed,int p_modifier_mask) {
	
	// wheel!	
	
	if (b.button_index==BUTTON_WHEEL_UP && b.pressed) {
		
		if (orientation==VERTICAL)
			set_val( get_val() - get_page() / 4.0 );
		else
			set_val( get_val() + get_page() / 4.0 );
		
	}
	if (b.button_index==BUTTON_WHEEL_DOWN && b.pressed) {
		
		if (orientation==HORIZONTAL)
			set_val( get_val() - get_page() / 4.0 );
		else
			set_val( get_val() + get_page() / 4.0  );
	}
	
	if (b.button_index!=BUTTON_LEFT)
		return;
	
	if (b.pressed) {
		
		int ofs = orientation==VERTICAL ? p_pos.y : p_pos.x ;
		int grabber_ofs = get_grabber_offset();
		int grabber_size = get_grabber_size();
		
		if ( ofs < grabber_ofs ) {
			
			set_val( get_val() - get_page() );
			
		} else if (ofs > grabber_ofs + grabber_size ) {
			
			set_val( get_val() + get_page() );
			
		} else {
			
			
			drag.active=true;
			drag.pos_at_click=get_click_pos(p_pos);
			drag.value_at_click=get_unit_value();
		}
		
		
	} else {
		
		drag.active=false;
	}
	
}
void ScrollBar::mouse_motion(const Point2& p_pos, const Point2& p_rel, int b.button_index_mask) {
	
	if (!drag.active)
		return;
	
	double value_ofs=drag.value_at_click+(get_click_pos(p_pos)-drag.pos_at_click);
	
	
	value_ofs=value_ofs*( get_max() - get_min() );
	if (value_ofs<get_min())
		value_ofs=get_min();
	if (value_ofs>(get_max()-get_page()))
		value_ofs=get_max()-get_page();
	if (get_val()==value_ofs)
		return; //dont bother if the value is the same
	
	set_val( value_ofs );
	
}

bool ScrollBar::key(unsigned long p_unicode, unsigned long p_scan_code,bool b.pressed,bool p_repeat,int p_modifier_mask) {
	
	if (!b.pressed)
		return false;
	
	switch (p_scan_code) {
		
	case KEY_LEFT: {
		
		if (orientation!=HORIZONTAL)
			return false;
		set_val( get_val() - get_step() );
		
	} break;
	case KEY_RIGHT: {
		
		if (orientation!=HORIZONTAL)
			return false;
		set_val( get_val() + get_step() );
		
	} break;
	case KEY_UP: {
		
		if (orientation!=VERTICAL)
			return false;
		
		set_val( get_val() - get_step() );
		
		
	} break;
	case KEY_DOWN: {
		
		if (orientation!=VERTICAL)
			return false;
		set_val( get_val() + get_step() );
		
	} break;
	case KEY_HOME: {
		
		set_val( get_min() );
		
	} break;
	case KEY_END: {
		
		set_val( get_max() );
		
	} break;
		
	default:
		return false;
		
	}
	
	return true;
}



#endif

void ScrollBar::_bind_methods() {

	ObjectTypeDB::bind_method(_MD("_input_event"),&ScrollBar::_input_event);
	ObjectTypeDB::bind_method(_MD("set_custom_step","step"),&ScrollBar::set_custom_step);
	ObjectTypeDB::bind_method(_MD("get_custom_step"),&ScrollBar::get_custom_step);

	ADD_PROPERTY( PropertyInfo(Variant::REAL,"custom_step",PROPERTY_HINT_RANGE,"-1,4096"), _SCS("set_custom_step"),_SCS("get_custom_step"));

}


ScrollBar::ScrollBar(Orientation p_orientation)
{


	orientation=p_orientation;
	hilite=HILITE_NONE;
	custom_step=-1;
		
	drag.active=false;
	
	if (focus_by_default)
		set_focus_mode( FOCUS_ALL );

		
}



ScrollBar::~ScrollBar()
{
}