/* ScummVM - Graphic Adventure Engine
 *
 * ScummVM is the legal property of its developers, whose names
 * are too numerous to list here. Please refer to the COPYRIGHT
 * file distributed with this source distribution.
 *
 * 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 3 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, see <http://www.gnu.org/licenses/>.
 *
 */

#include "ags/lib/std/utility.h"
#include "ags/engine/ac/screen_overlay.h"
#include "ags/shared/ac/sprite_cache.h"
#include "ags/shared/util/stream.h"
#include "ags/globals.h"

namespace AGS3 {

using namespace AGS::Shared;

Bitmap *ScreenOverlay::GetImage() const {
	return IsSpriteReference() ?
		_GP(spriteset)[_sprnum] :
		_pic.get();
}

void ScreenOverlay::SetImage(Shared::Bitmap *pic) {
	_flags &= ~kOver_SpriteReference;
	_pic.reset(pic);
	_sprnum = -1;
	offsetX = offsetY = 0;
	scaleWidth = scaleHeight = 0;
	const auto *img = GetImage();
	if (img) {
		scaleWidth = img->GetWidth();
		scaleHeight = img->GetHeight();
	}
	MarkChanged();
}

void ScreenOverlay::SetSpriteNum(int sprnum) {
	_flags |= kOver_SpriteReference;
	_pic.reset();
	_sprnum = sprnum;
	offsetX = offsetY = 0;
	scaleWidth = scaleHeight = 0;
	const auto *img = GetImage();
	if (img) {
		scaleWidth = img->GetWidth();
		scaleHeight = img->GetHeight();
	}
	MarkChanged();
}

void ScreenOverlay::ReadFromFile(Stream *in, bool &has_bitmap, int32_t cmp_ver) {
	_pic.reset();
	ddb = nullptr;
	in->ReadInt32(); // ddb 32-bit pointer value (nasty legacy format)
	int pic = in->ReadInt32();
	type = in->ReadInt32();
	x = in->ReadInt32();
	y = in->ReadInt32();
	timeout = in->ReadInt32();
	bgSpeechForChar = in->ReadInt32();
	associatedOverlayHandle = in->ReadInt32();
	if (cmp_ver >= 3) {
		_flags = in->ReadInt16();
	} else {
		if (in->ReadBool()) // has alpha
			_flags |= kOver_AlphaChannel;
		if (!(in->ReadBool())) // screen relative position
			_flags |= kOver_PositionAtRoomXY;
	}

	if (cmp_ver >= 1) {
		offsetX = in->ReadInt32();
		offsetY = in->ReadInt32();
	}
	if (cmp_ver >= 2) {
		zorder = in->ReadInt32();
		transparency = in->ReadInt32();
		scaleWidth = in->ReadInt32();
		scaleHeight = in->ReadInt32();
	}

	if (_flags & kOver_SpriteReference) {
		_sprnum = pic;
		has_bitmap = false;
	} else {
		_sprnum = -1;
		has_bitmap = pic != 0;
	}
}

void ScreenOverlay::WriteToFile(Stream *out) const {
	out->WriteInt32(0); // ddb 32-bit pointer value (nasty legacy format)
	if (_flags & kOver_SpriteReference)
		out->WriteInt32(_sprnum); // sprite reference
	else
		out->WriteInt32(_pic ? 1 : 0); // has bitmap
	out->WriteInt32(type);
	out->WriteInt32(x);
	out->WriteInt32(y);
	out->WriteInt32(timeout);
	out->WriteInt32(bgSpeechForChar);
	out->WriteInt32(associatedOverlayHandle);
	out->WriteInt16(_flags);
	// since cmp_ver = 1
	out->WriteInt32(offsetX);
	out->WriteInt32(offsetY);
	// since cmp_ver = 2
	out->WriteInt32(zorder);
	out->WriteInt32(transparency);
	out->WriteInt32(scaleWidth);
	out->WriteInt32(scaleHeight);
}

} // namespace AGS3