/* 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 "common/file.h"
#include "common/system.h"
#include "graphics/cursorman.h"
#include "sci/graphics/drivers/gfxdriver_intern.h"

namespace Sci {

class SCI0_HerculesDriver final : public SCI0_DOSPreVGADriver {
public:
	SCI0_HerculesDriver(uint32 monochromeColor, bool rgbRendering, bool cropImage);
	~SCI0_HerculesDriver() override;
	void copyRectToScreen(const byte *src, int srcX, int srcY, int pitch, int destX, int destY, int w, int h, const PaletteMod*, const byte*) override;
	void replaceCursor(const void *cursor, uint w, uint h, int hotspotX, int hotspotY, uint32 keycolor) override;
	Common::Point getMousePos() const override;
	void setMousePos(const Common::Point &pos) const override;
	void setShakePos(int shakeXOffset, int shakeYOffset) const override;
	void clearRect(const Common::Rect &r) const override;
	Common::Point getRealCoords(Common::Point &pos) const override;
	static bool validateMode(Common::Platform p) { return (p == Common::kPlatformDOS) && checkDriver(&_driverFile, 1); }
private:
	void setupRenderProc() override;
	const uint16 _centerX;
	const uint16 _centerY;
	byte _monochromePalette[6];
	const byte *_monochromePatterns;
	typedef void (*LineProc)(byte*&, const byte*, int, int, int, const byte*, const byte*);
	LineProc _renderLine;
	static const char *_driverFile;
};

SCI0_HerculesDriver::SCI0_HerculesDriver(uint32 monochromeColor, bool rgbRendering, bool cropImage) : SCI0_DOSPreVGADriver(2, cropImage ? 640 : 720, cropImage ? 300 : 350, rgbRendering),
	_centerX(cropImage ? 0 : 40), _centerY(cropImage ? 0 : 25), _monochromePatterns(nullptr), _renderLine(nullptr) {
	_monochromePalette[0] = _monochromePalette[1] = _monochromePalette[2] = 0;
	_monochromePalette[3] = (monochromeColor >> 16) & 0xff;
	_monochromePalette[4] = (monochromeColor >> 8) & 0xff;
	_monochromePalette[5] = monochromeColor & 0xff;
	assignPalette(_monochromePalette);
	bool unused = false;

	if (!(_monochromePatterns = SciGfxDrvInternal::monochrInit(_driverFile, unused)))
		GFXDRV_ERR_OPEN(_driverFile);
}

SCI0_HerculesDriver::~SCI0_HerculesDriver() {
	delete[] _monochromePatterns;
}

void SCI0_HerculesDriver::copyRectToScreen(const byte *src, int srcX, int srcY, int pitch, int destX, int destY, int w, int h, const PaletteMod*, const byte*) {
	GFXDRV_ASSERT_READY;

	byte *dst = _compositeBuffer;
	byte sw = destY & 1;
	src += (srcY * pitch + srcX);
	destY = (destY & ~1) * 3 / 2 + (destY & 1);
	int ty = destY & 7;
	int rh = 0;

	for (int i = 0; i < h; ++i) {
		const byte *src2 = src;
		_renderLine(dst, src2, w, srcX & 3, ty, _monochromePatterns, _internalPalette);
		ty = (ty + 1) & 7;
		++rh;

		if (sw & 1)
			sw ^= 2;

		if (sw != 3) {
			src += pitch;
			sw ^= 1;
		} else {
			--i;
		}
	}

	g_system->copyRectToScreen(_compositeBuffer, (w << 1) * _pixelSize, (destX << 1) + _centerX, destY + _centerY, w << 1, rh);
}

void SCI0_HerculesDriver::replaceCursor(const void *cursor, uint w, uint h, int hotspotX, int hotspotY, uint32 keycolor) {
	GFXDRV_ASSERT_READY;
	// Instead of implementing the original cursor rendering code, we rely on the 8 bit cursor that
	// has already been generated by the engine. We simply convert the colors as needed and scale the cursor...
	assert(keycolor == 1);
	keycolor = 0x0f;
	int alt = 0;
	const byte *s = reinterpret_cast<const byte *>(cursor);
	byte *d = _compositeBuffer;

	for (uint i = 0; i < h; ++i) {
		for (uint ii = 0; ii < (w << 1); ++ii) {
			*d++ = *s ? (*s ^ 0x0e) : 0;
			if (ii & 1)
				++s;
		}
		if (i & 1) {
			alt ^= 1;
			if (alt) {
				s -= w;
				--i;
			}
		}
	}

	CursorMan.replaceCursor(_compositeBuffer, w << 1, (h & ~1) * 3 / 2 + (h & 1), hotspotX << 1, (hotspotY & ~1) * 3 / 2 + (hotspotY & 1), keycolor);
}

Common::Point SCI0_HerculesDriver::getMousePos() const {
	Common::Point res = GfxDriver::getMousePos();
	res.x = CLIP<int>(res.x - _centerX, 0, 639) >> 1;
	res.y = (CLIP<int>(res.y - _centerY, 0, 299) * 2 + 1) / 3;
	return res;
}

void SCI0_HerculesDriver::setMousePos(const Common::Point &pos) const {
	g_system->warpMouse((pos.x << 1) + _centerX, (pos.y & ~1) * 3 / 2 + (pos.y & 1) + _centerY);
}

void SCI0_HerculesDriver::setShakePos(int shakeXOffset, int shakeYOffset) const {
	g_system->setShakePos(shakeXOffset << 1, (shakeYOffset & ~1) * 3 / 2 + (shakeYOffset & 1));
}

void SCI0_HerculesDriver::clearRect(const Common::Rect &r) const {
	Common::Rect r2((r.left << 1) + _centerX, (r.top & ~1) * 3 / 2 + (r.top & 1) + _centerY, (r.right << 1) + _centerX, (r.bottom & ~1) * 3 / 2 + (r.bottom & 1) + _centerY);
	GfxDriver::clearRect(r2);
}

Common::Point SCI0_HerculesDriver::getRealCoords(Common::Point &pos) const {
	return Common::Point((pos.x << 1) + _centerX, (pos.y & ~1) * 3 / 2 + (pos.y & 1) + _centerY);
}

template <typename T> void herculesRenderLine(byte *&dst, const byte *src, int w, int tx, int ty, const byte *patterns, const byte *pal) {
	T *d = reinterpret_cast<T*>(dst);
	const T *p = reinterpret_cast<const T*>(pal);

	for (int i = 0; i < w; ++i) {
		byte pt = patterns[((*src++ & 0x0f) << 3) + ty] >> (6 - (tx << 1));
		if (sizeof(T) == 1) {
			*d++ = (pt >> 1) & 1;
			*d++ = pt & 1;
		} else {
			*d++ = p[(pt >> 1) & 1];
			*d++ = p[pt & 1];
		}
		tx = (tx + 1) & 3;
	}

	dst = reinterpret_cast<byte*>(d);
}

void SCI0_HerculesDriver::setupRenderProc() {
	static const LineProc lineProcs[] = {
		&herculesRenderLine<byte>,
		&herculesRenderLine<uint16>,
		&herculesRenderLine<uint32>
	};

	assert((_pixelSize >> 1) < ARRAYSIZE(lineProcs));
	_renderLine = lineProcs[_pixelSize >> 1];
}

const char *SCI0_HerculesDriver::_driverFile = "HERCMONO.DRV";

SCI_GFXDRV_VALIDATE_IMPL(SCI0_Hercules)

GfxDriver *SCI0_HerculesDriver_create(int rgbRendering, ...) {
	static const uint32 monochromeColors[] = { 0xffbf66, 0x66ff66, 0xffffff };
	va_list args;
	va_start(args, rgbRendering);
	int config = CLIP<int>(va_arg(args, int), 0, ARRAYSIZE(monochromeColors) - 1);
	va_end(args);

	return new SCI0_HerculesDriver(monochromeColors[config], rgbRendering != 0, false);
}

} // End of namespace Sci