/* Copyright (C) 2025 Wildfire Games.
 * This file is part of 0 A.D.
 *
 * 0 A.D. 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.
 *
 * 0 A.D. 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 0 A.D.  If not, see <http://www.gnu.org/licenses/>.
 */

/*
GUI Object Base - Text Owner

--Overview--

	Interface class that enhance the IGUIObject with
	 cached CGUIStrings. This class is not at all needed,
	 and many controls that will use CGUIStrings might
	 not use this, but does help for regular usage such
	 as a text-box, a button, a radio button etc.
*/

#ifndef INCLUDED_IGUITEXTOWNER
#define INCLUDED_IGUITEXTOWNER

#include "gui/CGUISetting.h"
#include "lib/code_annotation.h"
#include "maths/Rect.h"

#include <cstddef>
#include <vector>

class CCanvas2D;
class CGUIString;
class CGUIText;
class CStrW;
class CVector2D;
class IGUIObject;
enum class EAlign;
enum class EVAlign;
struct CGUIColor;
struct SGUIMessage;

/**
 * Framework for handling Output text.
 */
class IGUITextOwner
{
	NONCOPYABLE(IGUITextOwner);

public:
	IGUITextOwner(IGUIObject& pObject);
	virtual ~IGUITextOwner();

	/**
	 * Adds a text object.
	 */
	CGUIText& AddText();

	/**
	 * Adds a text generated by the given arguments.
	 */
	CGUIText& AddText(const CGUIString& Text, const CStrW& Font, const float& Width, const float& BufferZone);

	/**
	 * @see IGUIObject#HandleMessage()
	 */
	virtual void HandleMessage(SGUIMessage& Message);

	/**
	 * @see IGUIObject#UpdateCachedSize()
	 */
	virtual void UpdateCachedSize();

	/**
	 * Draws the Text.
	 *
	 * @param canvas Canvas to draw on.
	 * @param index Index value of text. Mostly this will be 0
	 * @param color
	 * @param pos Position
	 * @param clipping Clipping rectangle, don't even add a parameter
	 *		  to get no clipping.
	 */
	virtual void DrawText(CCanvas2D& canvas, size_t index, const CGUIColor& color, const CVector2D& pos, const CRect& clipping = CRect());

protected:
	/**
	 * Setup texts. Functions that sets up all texts when changes have been made.
	 */
	virtual void SetupText() = 0;

	/**
	 * Regenerate the text in case it is invalid. Should only be called when inevitable.
	 */
	virtual void UpdateText();

	/**
	 * Whether the cached text is currently valid (if not then SetupText will be called by Draw)
	 */
	bool m_GeneratedTextsValid;

	/**
	 * Texts that are generated and ready to be rendered.
	 */
	std::vector<CGUIText> m_GeneratedTexts;

	/**
	 * Calculate the position for the text, based on the alignment.
	 */
	void CalculateTextPosition(CRect& ObjSize, CVector2D& TextPos, CGUIText& Text);

	CGUISimpleSetting<EAlign> m_TextAlign;
	CGUISimpleSetting<EVAlign> m_TextVAlign;

private:
	/**
	 * Reference to the IGUIObject.
	 * Private, because we don't want to inherit it in multiple classes.
	 */
	IGUIObject& m_pObject;
};

#endif // INCLUDED_IGUITEXTOWNER
