#ifndef UI_ELEMENT_H
#define UI_ELEMENT_H

#include "UIStructs.h"
#include "UIPainter.h"

#undef min
#undef max
#include <vector>

class UIElement {

protected:

	UIRect rect;
	bool _visible = true;
	bool _needsRedraw = true;
	
	bool opaque = true;
	bool focus = false;
	
	std::vector<UIElement*> children;

	static constexpr const char* TAG = "UIElement";

public:

	void setOpaque(bool opaque) {
		this->opaque = opaque;
	}

	void setRect(const UIRect r) {
		this->rect = r;
		setNeedsRedraw();
		reLayout();
	}
	void setRect(const uint16_t x, const uint16_t y, const uint16_t w, const uint16_t h) {
		this->rect = UIRect(x,y,w,h);
		setNeedsRedraw();
		reLayout();
	}
	const UIRect& getRect() const {
		return rect;
	}

	void setVisible(bool visible) {
		this->_visible = visible;
		setNeedsRedraw();
	}
	bool isVisible() const {
		return this->_visible;
	}

	void setFocus(bool focus) {
		this->focus = focus;
		setNeedsRedraw();
	}

	void setNeedsRedraw() {
		this->_needsRedraw = true;
	}
	bool needsRedraw() const {
		return this->_needsRedraw;
	}

	void addChild(UIElement* e) {
		children.push_back(e);
	}




protected:

	friend class UI;

	virtual void draw(UIPainter& p) {;}

	/** layout needs updating */
	virtual void reLayout() {;}

	virtual void onTouchDown(uint16_t, uint16_t) {;}	// relative (x,y) coordinate
	virtual void onTouch(uint16_t, uint16_t) {;}		// relative (x,y) coordinate
	virtual void onTouchUp() {;}

protected:

	UIElement* _onTouch(const uint16_t x, const uint16_t y) {


		// if i'm invisible, ignore for me and children
		if (!isVisible())				{return nullptr;}

		// touch outside of me, ignore for me and children
		if (!getRect().contains(x,y))	{return nullptr;}

		// find first child that takes the event
		for (UIElement* e : children) {
			UIElement* taken = e->_onTouch(x, y);
			if (taken) {return taken;}
		}

		// take the event myself
		const uint16_t x1 = x - getRect().x;	// (x,y) relative to elements top-left
		const uint16_t y1 = y - getRect().y;
		debugMod2(TAG, "onTouchDown(%d,%d)", x1, y1);
		onTouchDown(x1, y1);
		return this;

	}

	void _draw(UIPainter& p) {

		// if hiden, ignore for me and children
		if (!_visible) {return;}

		// draw myself (if needed)
		if (_needsRedraw) {
			draw(p);
			_needsRedraw = false;
		}

		// call for children as well
		for (UIElement* child : children) {
			child->_draw(p);
		}

	}


};

#endif // UI_ELEMENT_H