/* GemRB - Infinity Engine Emulator
 * Copyright (C) 2003 The GemRB Project
 *
 * This program 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.
 *
 * This program 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 this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 *
 *
 */

#ifndef SPRITESHEET_H
#define SPRITESHEET_H

#include "Sprite2D.h"

#include "Video/Video.h"

#include <map>
#include <utility>

namespace GemRB {

template <typename KeyType>
class SpriteSheet {
protected:
	Region SheetRegion; // FIXME: this is only needed because of a subclass
	std::map<KeyType, Region> RegionMap;

	explicit SpriteSheet(Video* video)
	: video(video) {};

public:
	Holder<Sprite2D> Sheet;
	Video* video;

public:
	SpriteSheet(Video* video, Holder<Sprite2D> sheet)
	: Sheet(std::move(sheet)), video(video) {
		SheetRegion = Sheet->Frame;
	};

	virtual ~SpriteSheet() noexcept = default;

	const Region& operator[](KeyType key) {
		return RegionMap[key];
	}

	// return the passed in region, clipped to the sprite dimensions or a region with -1 w/h if outside the sprite bounds
	const Region& MapSheetSegment(KeyType key, const Region& rgn) {
		Region intersection = rgn.Intersect(SheetRegion);
		if (!intersection.size.IsInvalid()) {
			if (RegionMap.emplace(key, intersection).second) {
				return RegionMap[key];
			}
			// FIXME: should we return something like Region(0,0,0,0) here?
			// maybe we should just use Atlas[key] = intersection too.
		}
		const static Region nullRgn(0,0, -1,-1);
		return nullRgn;
	}

	void Draw(KeyType key, const Region& dest, BlitFlags flags, const Color& tint) const {
		const auto& i = RegionMap.find(key);
		if (i != RegionMap.end()) {
			video->BlitSprite(Sheet, i->second, dest, flags, tint);
		}
	}
};

}

#endif  // ! SPRITESHEET_H
