// Residual - Virtual machine to run LucasArts' 3D adventure games
// Copyright (C) 2003-2004 The ScummVM-Residual Team (www.scummvm.org)
//
//  This library is free software; you can redistribute it and/or
//  modify it under the terms of the GNU Lesser General Public
//  License as published by the Free Software Foundation; either
//  version 2.1 of the License, or (at your option) any later version.
//
//  This library 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
//  Lesser General Public License for more details.
//
//  You should have received a copy of the GNU Lesser General Public
//  License along with this library; if not, write to the Free Software
//  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307  USA

#include "driver_gl.h"		// Driver interface
#include "debug.h"		// error(), warning(), etc

Driver *g_driver;

// Hacky includes for temporary font rendering
#ifndef WIN32
	#include <GL/glx.h>
	#include <X11/Xlib.h>
#else
	#include <SDL_syswm.h>
	#include <windows.h>
#endif

// Constructor. Should create the driver and open screens, etc.
Driver::Driver(int screenW, int screenH, int screenBPP) {
	char GLDriver[1024];

	SDL_GL_SetAttribute(SDL_GL_RED_SIZE, 5);
	SDL_GL_SetAttribute(SDL_GL_GREEN_SIZE, 5);
	SDL_GL_SetAttribute(SDL_GL_BLUE_SIZE, 5);
	SDL_GL_SetAttribute(SDL_GL_DEPTH_SIZE, 16);
	SDL_GL_SetAttribute(SDL_GL_DOUBLEBUFFER, 1);

	if (SDL_SetVideoMode(screenW, screenH, screenBPP, SDL_OPENGL) == 0)
		error("Could not initialize video");

	sprintf(GLDriver, "Residual: %s/%s", glGetString(GL_VENDOR), glGetString(GL_RENDERER));
	SDL_WM_SetCaption(GLDriver, "Residual");

	// FIXME: Hacky temporary font renderer code
	hackFont = glGenLists(256);
#ifdef WIN32
	{
		HDC   hDC;
		HFONT font;
		SDL_SysWMinfo wmi;
		SDL_VERSION(&wmi.version);
		SDL_GetWMInfo(&wmi);

		hDC = GetDC(wmi.window);
		font = CreateFont(0, 0, 0, 0, FW_NORMAL, FALSE, FALSE, FALSE, ANSI_CHARSET,
			OUT_TT_PRECIS, CLIP_DEFAULT_PRECIS, 0 , FF_DONTCARE|DEFAULT_PITCH, "Courier New");
		SelectObject(hDC, font);
		wglUseFontBitmaps(hDC, 0, 256, hackFont);
	}
#else
	{
		//Display *dpy = XOpenDisplay(NULL);
		//XFontStruct *XFont = XLoadQueryFont(dpy, "-misc-fixed-medium-r-*-*-20-*-*-*-*-*-*-*" );
		//glXUseXFont(XFont->fid, 0, 256, hackFont);
		//XFreeFont(dpy, XFont);
		//XCloseDisplay(dpy);
	}
#endif

	_smushNumTex = 0;
}

void Driver::setupCamera(float fov, float nclip, float fclip, float roll) {
	// Set perspective transformation
	glMatrixMode(GL_PROJECTION);
	glLoadIdentity();
	//gluPerspective(std::atan(std::tan(fov_ / 2 * (M_PI / 180)) * 0.75) * 2 * (180 / M_PI), 4.0f / 3, nclip_, fclip_);

	float right = nclip * std::tan(fov / 2 * (M_PI / 180));
	glFrustum(-right, right, -right * 0.75, right * 0.75, nclip, fclip);

	glMatrixMode(GL_MODELVIEW);
	glLoadIdentity();

	Vector3d up_vec(0, 0, 1);
	glRotatef(roll, 0, 0, -1);
}

void Driver::positionCamera(Vector3d pos, Vector3d interest) {
	Vector3d up_vec(0, 0, 1);

	if (pos.x() == interest.x() && pos.y() == interest.y())
		up_vec = Vector3d(0, 1, 0);

	gluLookAt(pos.x(), pos.y(), pos.z(), 
		interest.x(), interest.y(), interest.z(),
		up_vec.x(), up_vec.y(), up_vec.z());

}

void Driver::clearScreen() {
	glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
}

void Driver::flipBuffer() {
	SDL_GL_SwapBuffers();
}

void Driver::startActorDraw(Vector3d pos, float yaw, float pitch, float roll) {
	glMatrixMode(GL_MODELVIEW);
	glPushMatrix();
	glTranslatef(pos.x(), pos.y(), pos.z());
	glRotatef(yaw, 0, 0, 1);
	glRotatef(pitch, 1, 0, 0);
	glRotatef(roll, 0, 1, 0);
}

void Driver::finishActorDraw() {
	glPopMatrix();
}

void Driver::drawDepthBitmap(int num, int x, int y, int w, int h, char **data) {
	if (num != 0) {
		warning("Animation not handled yet in GL texture path !\n");
	}

	glRasterPos2i(x, y);
	glEnable(GL_DEPTH_TEST);
	glDepthFunc(GL_ALWAYS);
	glColorMask(GL_FALSE, GL_FALSE, GL_FALSE, GL_FALSE);
	glDepthMask(GL_TRUE);

	// This loop here is to prevent using PixelZoom that may be unoptimized for the 1.0 / -1.0 case
	// in some drivers...

	for (int row = 0; row < h; row++) {
		glRasterPos2i(x, y + row + 1);
		//glDrawPixels(w, 1, GL_DEPTH_COMPONENT, GL_UNSIGNED_SHORT, data[num] + (2 * row * w));
	}
	glColorMask(GL_TRUE, GL_TRUE, GL_TRUE, GL_TRUE);
	glDepthFunc(GL_LESS);
}

void Driver::drawHackFont(int x, int y, const char *text, Color &fgColor) {
	glMatrixMode(GL_PROJECTION);
	glPushMatrix();
	glLoadIdentity();
	glOrtho(0, 640, 480, 0, 0, 1);

	glMatrixMode(GL_MODELVIEW);
	glLoadIdentity();

	glColor3f(fgColor.red(), fgColor.green(), fgColor.blue());
	glRasterPos2i(x, y);

	glListBase(hackFont);
	glCallLists(strlen(strrchr(text, '/')) - 1, GL_UNSIGNED_BYTE, strrchr(text, '/') + 1);

	glMatrixMode( GL_PROJECTION );
	glPopMatrix();
}

void Driver::prepareSmushFrame(int width, int height, byte *bitmap) {
	// remove if already exist
	if (_smushNumTex > 0) {
		glDeleteTextures(_smushNumTex, _smushTexIds);
		delete[] _smushTexIds;
		_smushNumTex = 0;
	}

	// create texture
	_smushNumTex = ((width + (BITMAP_TEXTURE_SIZE - 1)) / BITMAP_TEXTURE_SIZE) *
		((height + (BITMAP_TEXTURE_SIZE - 1)) / BITMAP_TEXTURE_SIZE);
	_smushTexIds = new GLuint[_smushNumTex];
	glGenTextures(_smushNumTex, _smushTexIds);
	for (int i = 0; i < _smushNumTex; i++) {
		glBindTexture(GL_TEXTURE_2D, _smushTexIds[i]);
		glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
		glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
		glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP);
		glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP);
		glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB,
			BITMAP_TEXTURE_SIZE, BITMAP_TEXTURE_SIZE, 0,
			GL_RGB, GL_UNSIGNED_SHORT_5_6_5, NULL);
	}

	glPixelStorei(GL_UNPACK_ALIGNMENT, 2);
	glPixelStorei(GL_UNPACK_ROW_LENGTH, width);

	int curTexIdx = 0;
	for (int y = 0; y < height; y += BITMAP_TEXTURE_SIZE) {
		for (int x = 0; x < width; x += BITMAP_TEXTURE_SIZE) {
			int t_width = (x + BITMAP_TEXTURE_SIZE >= width) ? (width - x) : BITMAP_TEXTURE_SIZE;
			int t_height = (y + BITMAP_TEXTURE_SIZE >= height) ? (height - y) : BITMAP_TEXTURE_SIZE;
			glBindTexture(GL_TEXTURE_2D, _smushTexIds[curTexIdx]);
			glTexSubImage2D(GL_TEXTURE_2D, 
				0,
				0, 0,
				t_width, t_height,
				GL_RGB,
				GL_UNSIGNED_SHORT_5_6_5,
				bitmap + (y * 2 * width) + (2 * x));
			curTexIdx++;
		}
	}
	glPixelStorei(GL_UNPACK_ALIGNMENT, 4);
	glPixelStorei(GL_UNPACK_ROW_LENGTH, 0);
	_smushWidth = width;
	_smushHeight = height;
}

void Driver::drawSmushFrame(int offsetX, int offsetY) {
	// prepare view
	glMatrixMode(GL_PROJECTION);
	glLoadIdentity();
	glOrtho(0, 640, 480, 0, 0, 1);
	glMatrixMode(GL_MODELVIEW);
	glLoadIdentity();
	glMatrixMode(GL_TEXTURE);
	glLoadIdentity();
	// A lot more may need to be put there : disabling Alpha test, blending, ...
	// For now, just keep this here :-)

	glDisable(GL_LIGHTING);
	glEnable(GL_TEXTURE_2D);

	// draw
	glDisable(GL_DEPTH_TEST);
	glDepthMask(GL_FALSE);
	glEnable(GL_SCISSOR_TEST);

	int curTexIdx = 0;
	for (int y = 0; y < _smushHeight; y += BITMAP_TEXTURE_SIZE) {
		for (int x = 0; x < _smushWidth; x += BITMAP_TEXTURE_SIZE) {
			int t_width = (x + BITMAP_TEXTURE_SIZE >= _smushWidth) ? (_smushWidth - x) : BITMAP_TEXTURE_SIZE;
			int t_height = (y + BITMAP_TEXTURE_SIZE >= _smushHeight) ? (_smushHeight - y) : BITMAP_TEXTURE_SIZE;
			glBindTexture(GL_TEXTURE_2D, _smushTexIds[curTexIdx]);
			glScissor(x + offsetX, 480 - (y + t_height + offsetY), x + offsetX + t_width, 480 - (y + offsetY));
			glBegin(GL_QUADS);
			glTexCoord2f(0, 0);
			glVertex2i(x + offsetX, y + offsetY);
			glTexCoord2f(1.0, 0.0);
			glVertex2i(x + offsetX + BITMAP_TEXTURE_SIZE, y + offsetY);
			glTexCoord2f(1.0, 1.0);
			glVertex2i(x + offsetX + BITMAP_TEXTURE_SIZE, y + offsetY + BITMAP_TEXTURE_SIZE);
			glTexCoord2f(0.0, 1.0);
			glVertex2i(x + offsetX, y + offsetY + BITMAP_TEXTURE_SIZE);
			glEnd();
			curTexIdx++;
		}
	}

	glDisable(GL_SCISSOR_TEST);
	glDisable(GL_TEXTURE_2D);
	glDepthMask(GL_TRUE);
	glEnable(GL_DEPTH_TEST);
}