/*
Copyright (C) 1996-1997 Id Software, Inc.

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., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.

*/
// vid_glx.c -- Linux GLX driver

#include <termios.h>
#include <sys/ioctl.h>
#include <sys/stat.h>
#include <sys/vt.h>
#include <stdarg.h>
#include <stdio.h>
#include <signal.h>

#include <dlfcn.h>

#include "quakedef.h"

#include <GL/glx.h>

#include <X11/keysym.h>
#include <X11/cursorfont.h>

#include <X11/extensions/xf86dga.h>
#include <X11/extensions/xf86vmode.h>

#define	WARP_WIDTH	320
#define	WARP_HEIGHT	200

static	Display		*dpy = NULL;
static	Window		win;
static	GLXContext	ctx = NULL;

static	float	old_windowed_mouse = 0, mouse_x, mouse_y, old_mouse_x, old_mouse_y;

#define KEY_MASK (KeyPressMask | KeyReleaseMask)
#define MOUSE_MASK (ButtonPressMask | ButtonReleaseMask | PointerMotionMask)
#define X_MASK (KEY_MASK | MOUSE_MASK | VisibilityChangeMask)
 
unsigned	short	*currentgammaramp = NULL;
static unsigned	short	systemgammaramp[3][256];

qboolean vid_gammaworks = false;
qboolean vid_hwgamma_enabled = false;
qboolean customgamma = false;
qboolean fullsbardraw = false;
qboolean fullscreen = false;

static	int	scr_width, scr_height, scrnum;

static qboolean dgamouse = false, dgakeyb = false;

static	qboolean	vidmode_ext = false;
static	XF86VidModeModeInfo **vidmodes;
static	int		num_vidmodes;
static	qboolean	vidmode_active = false;

cvar_t	vid_mode = {"vid_mode", "0"};
qboolean OnChange_windowed_mouse (cvar_t *var, char *value);
cvar_t	_windowed_mouse = {"_windowed_mouse", "1", 0, OnChange_windowed_mouse};
cvar_t	m_filter = {"m_filter", "0"};
cvar_t	cl_keypad = {"cl_keypad", "1"};
cvar_t	vid_hwgammacontrol = {"vid_hwgammacontrol", "1"};

//===========================================

void D_BeginDirectRect (int x, int y, byte *pbitmap, int width, int height)
{
}

void D_EndDirectRect (int x, int y, int width, int height)
{
}

void VID_LockBuffer (void)
{
}

void VID_UnlockBuffer (void)
{
}

static int XLateKey (XKeyEvent *ev)
{
	int	key, kp;
	char	buf[64];
	KeySym	keysym;

	key = 0;
	kp = (int)cl_keypad.value;

	XLookupString (ev, buf, sizeof buf, &keysym, 0);

	switch (keysym)
	{
	case XK_Scroll_Lock: key = K_SCRLCK; break;

	case XK_Caps_Lock: key = K_CAPSLOCK; break;

	case XK_Num_Lock: key = kp ? KP_NUMLOCK : K_PAUSE; break;

	case XK_KP_Page_Up: key = kp ? KP_PGUP : K_PGUP; break;
	case XK_Page_Up: key = K_PGUP; break;

	case XK_KP_Page_Down: key = kp ? KP_PGDN : K_PGDN; break;
	case XK_Page_Down: key = K_PGDN; break;

	case XK_KP_Home: key = kp ? KP_HOME : K_HOME; break;
	case XK_Home: key = K_HOME; break;

	case XK_KP_End: key = kp ? KP_END : K_END; break;
	case XK_End: key = K_END; break;

	case XK_KP_Left: key = kp ? KP_LEFTARROW : K_LEFTARROW; break;
	case XK_Left: key = K_LEFTARROW; break;

	case XK_KP_Right: key = kp ? KP_RIGHTARROW : K_RIGHTARROW; break;
	case XK_Right: key = K_RIGHTARROW; break;

	case XK_KP_Down: key = kp ? KP_DOWNARROW : K_DOWNARROW; break;

	case XK_Down: key = K_DOWNARROW; break;

	case XK_KP_Up: key = kp ? KP_UPARROW : K_UPARROW; break;

	case XK_Up: key = K_UPARROW; break;

	case XK_Escape: key = K_ESCAPE; break;

	case XK_KP_Enter: key = kp ? KP_ENTER : K_ENTER; break;

	case XK_Return: key = K_ENTER; break;

	case XK_Tab: key = K_TAB; break;

	case XK_F1: key = K_F1; break;

	case XK_F2: key = K_F2; break;

	case XK_F3: key = K_F3; break;

	case XK_F4: key = K_F4; break;

	case XK_F5: key = K_F5; break;

	case XK_F6: key = K_F6; break;

	case XK_F7: key = K_F7; break;

	case XK_F8: key = K_F8; break;

	case XK_F9: key = K_F9; break;

	case XK_F10: key = K_F10; break;

	case XK_F11: key = K_F11; break;

	case XK_F12: key = K_F12; break;

	case XK_BackSpace: key = K_BACKSPACE; break;

	case XK_KP_Delete: key = kp ? KP_DEL : K_DEL; break;
	case XK_Delete: key = K_DEL; break;

	case XK_Pause: key = K_PAUSE; break;

	case XK_Shift_L: key = K_LSHIFT; break;								
	case XK_Shift_R: key = K_RSHIFT; break;

	case XK_Execute:
	case XK_Control_L: key = K_LCTRL; break;
	case XK_Control_R: key = K_RCTRL; break;

	case XK_Alt_L:
	case XK_Meta_L: key = K_LALT; break;								
	case XK_Alt_R:
	case XK_Meta_R: key = K_RALT; break;

	case XK_Super_L: key = K_LWIN; break;
	case XK_Super_R: key = K_RWIN; break;
	case XK_Menu: key = K_MENU; break;

	case XK_KP_Begin: key = kp ? KP_5 : '5'; break;

	case XK_KP_Insert: key = kp ? KP_INS : K_INS; break;
	case XK_Insert: key = K_INS; break;

	case XK_KP_Multiply: key = kp ? KP_STAR : '*'; break;

	case XK_KP_Add: key = kp ? KP_PLUS : '+'; break;

	case XK_KP_Subtract: key = kp ? KP_MINUS : '-'; break;

	case XK_KP_Divide: key = kp ? KP_SLASH : '/'; break;

	default:
		key = *(unsigned char *)buf;
		if (key >= 'A' && key <= 'Z')
			key = key - 'A' + 'a';
		break;
	} 

	return key;
}

static void install_grabs (void)
{
	int	DGAflags = 0;

	XGrabPointer (dpy, win, True, 0, GrabModeAsync, GrabModeAsync, win, None, CurrentTime);

	if (!COM_CheckParm("-nomdga"))
		DGAflags |= XF86DGADirectMouse;
	if (!COM_CheckParm("-nokdga"))
		DGAflags |= XF86DGADirectKeyb;

	if (!COM_CheckParm("-nodga") && DGAflags)
	{
		XF86DGADirectVideo (dpy, DefaultScreen(dpy), DGAflags);
		if (DGAflags & XF86DGADirectMouse)
			dgamouse = true;
		if (DGAflags & XF86DGADirectKeyb)
			dgakeyb = true;
	} 
	else
	{
		XWarpPointer (dpy, None, win, 0, 0, 0, 0, vid.width / 2, vid.height / 2);
	}

	XGrabKeyboard (dpy, win, False, GrabModeAsync, GrabModeAsync, CurrentTime);
}

static void uninstall_grabs (void)
{
	if (dgamouse || dgakeyb)
	{
		XF86DGADirectVideo (dpy, DefaultScreen(dpy), 0);
		dgamouse = dgakeyb = false;
	}

	XUngrabPointer (dpy, CurrentTime);
	XUngrabKeyboard (dpy, CurrentTime);
}

qboolean OnChange_windowed_mouse (cvar_t *var, char *value)
{
	if (vidmode_active && !Q_atof(value))
	{
		Con_Printf ("Cannot turn %s off when using -fullscreen mode\n", var->name);
		return true;
	}

	return false;
}

static void GetEvent (void)
{
	XEvent	event;

	if (!dpy)
		return;

	XNextEvent (dpy, &event);

	switch (event.type)
	{
	case KeyPress:
	case KeyRelease:
		Key_Event (XLateKey(&event.xkey), event.type == KeyPress);
		break;

	case MotionNotify:
		if (_windowed_mouse.value)
		{
			if (dgamouse)
			{
				mouse_x += event.xmotion.x_root;
				mouse_y += event.xmotion.y_root;
			}
			else
			{
				mouse_x = ((int)event.xmotion.x - (int)(vid.width / 2));
				mouse_y = ((int)event.xmotion.y - (int)(vid.height / 2));

				// move the mouse to the window center again
				XSelectInput (dpy, win, X_MASK & ~PointerMotionMask);
				XWarpPointer (dpy, None, win, 0, 0, 0, 0, (vid.width / 2), (vid.height / 2));
				XSelectInput (dpy, win, X_MASK);
			}
		}
		break;

	case ButtonPress:
	case ButtonRelease:
		switch (event.xbutton.button)
		{
		case 1:
			Key_Event (K_MOUSE1, event.type == ButtonPress);
			break;

		case 2:
			Key_Event (K_MOUSE3, event.type == ButtonPress);
			break;

		case 3:
			Key_Event (K_MOUSE2, event.type == ButtonPress);
			break;

		case 4:
			Key_Event (K_MWHEELUP, event.type == ButtonPress);
			break;

		case 5:
			Key_Event (K_MWHEELDOWN, event.type == ButtonPress);
			break;
		}
		break;
	}

	if (old_windowed_mouse != _windowed_mouse.value)
	{
		old_windowed_mouse = _windowed_mouse.value;

		if (!_windowed_mouse.value)
			uninstall_grabs ();
		else
			install_grabs ();
	}
}

void signal_handler (int sig)
{
	printf ("Received signal %d, exiting...\n", sig);
	Sys_Quit ();
	exit (0);
}

void InitSig (void)
{
	signal (SIGHUP, signal_handler);
	signal (SIGINT, signal_handler);
	signal (SIGQUIT, signal_handler);
	signal (SIGILL, signal_handler);
	signal (SIGTRAP, signal_handler);
	signal (SIGIOT, signal_handler);
	signal (SIGBUS, signal_handler);
	signal (SIGFPE, signal_handler);
	signal (SIGSEGV, signal_handler);
	signal (SIGTERM, signal_handler);
}

void VID_ShiftPalette (unsigned char *p)
{
}

void InitHWGamma (void)
{
	int	xf86vm_gammaramp_size;

	if (COM_CheckParm("-nohwgamma"))
		return;

	XF86VidModeGetGammaRampSize (dpy, scrnum, &xf86vm_gammaramp_size);

	vid_gammaworks = (xf86vm_gammaramp_size == 256);
	if (vid_gammaworks)
		XF86VidModeGetGammaRamp (dpy, scrnum, xf86vm_gammaramp_size, systemgammaramp[0], systemgammaramp[1], systemgammaramp[2]);
}

void VID_SetDeviceGammaRamp (unsigned short *ramps)
{
	if (vid_gammaworks)
	{
		currentgammaramp = ramps;
		if (vid_hwgamma_enabled)
		{
			XF86VidModeSetGammaRamp (dpy, scrnum, 256, ramps, ramps + 256, ramps + 512);
			customgamma = true;
		}
	}
}

void RestoreHWGamma (void)
{
	if (vid_gammaworks && customgamma)
	{
		customgamma = false;
		XF86VidModeSetGammaRamp (dpy, scrnum, 256, systemgammaramp[0], systemgammaramp[1], systemgammaramp[2]);
	}
}

/*
=================
GL_BeginRendering
=================
*/
void GL_BeginRendering (int *x, int *y, int *width, int *height)
{
	*x = *y = 0;
	*width = scr_width;
	*height = scr_height;
}

/*
=================
GL_EndRendering
=================
*/
void GL_EndRendering (void)
{
	static qboolean old_hwgamma_enabled;

	vid_hwgamma_enabled = vid_hwgammacontrol.value && vid_gammaworks;
	vid_hwgamma_enabled = vid_hwgamma_enabled && (fullscreen || vid_hwgammacontrol.value == 2);
	if (vid_hwgamma_enabled != old_hwgamma_enabled)
	{
		old_hwgamma_enabled = vid_hwgamma_enabled;
		if (vid_hwgamma_enabled && currentgammaramp)
			VID_SetDeviceGammaRamp (currentgammaramp);
		else
			RestoreHWGamma ();
	}

	glFlush ();
	glXSwapBuffers (dpy, win);

	if (fullsbardraw)
		Sbar_Changed ();
}

void VID_Shutdown (void)
{
	if (!ctx)
		return;

	uninstall_grabs ();
	
	RestoreHWGamma ();

	if (dpy)
	{
		glXDestroyContext (dpy, ctx);
		if (win)
			XDestroyWindow (dpy, win);
		if (vidmode_active)
			XF86VidModeSwitchToMode (dpy, scrnum, vidmodes[0]);
		XCloseDisplay (dpy);
		vidmode_active = false;
	}
}

static Cursor CreateNullCursor (Display *display, Window root)
{
	Pixmap		cursormask;
	XGCValues	xgc;
	GC		gc;
	XColor		dummycolour;
	Cursor		cursor;

	cursormask = XCreatePixmap (display, root, 1, 1, 1);
	xgc.function = GXclear;
	gc = XCreateGC (display, cursormask, GCFunction, &xgc);
	XFillRectangle (display, cursormask, gc, 0, 0, 1, 1);
	dummycolour.pixel = 0;
	dummycolour.red = 0;
	dummycolour.flags = 04;
	cursor = XCreatePixmapCursor (display, cursormask, cursormask, &dummycolour, &dummycolour, 0, 0);
	XFreePixmap (display, cursormask);
	XFreeGC (display, gc);

	return cursor;
}

void VID_Init (unsigned char *palette)
{
	int attrib[] = {
		GLX_RGBA,
		GLX_RED_SIZE, 1,
		GLX_GREEN_SIZE, 1,
		GLX_BLUE_SIZE, 1,
		GLX_DOUBLEBUFFER,
		GLX_DEPTH_SIZE, 1,
		None
	};
	int		i, width = 640, height = 480;
	XSetWindowAttributes attr;
	unsigned long	mask;
	Window		root;
	XVisualInfo	*visinfo;
	int		MajorVersion, MinorVersion, actualWidth, actualHeight;

	Cvar_Register (&vid_mode);
	Cvar_Register (&_windowed_mouse);
	Cvar_Register (&m_filter);
	Cvar_Register (&cl_keypad);
	Cvar_Register (&vid_hwgammacontrol);
	
	vid.maxwarpwidth = WARP_WIDTH;
	vid.maxwarpheight = WARP_HEIGHT;
	vid.colormap = host_colormap;
	vid.fullbright = 256 - LittleLong (*((int *)vid.colormap + 2048));

	if (!(dpy = XOpenDisplay(NULL)))
		Sys_Error ("Error: couldn't open the X display");

	if (!(visinfo = glXChooseVisual(dpy, scrnum, attrib)))
		Sys_Error ("Error: couldn't get an RGB, Double-buffered, Depth visual");

	scrnum = DefaultScreen (dpy);
	root = RootWindow (dpy, scrnum);

	if (COM_CheckParm("-fullscreen"))
		fullscreen = true;

	// set vid parameters
	if (COM_CheckParm("-current"))
	{
		width = DisplayWidth (dpy, scrnum);
		height = DisplayHeight (dpy, scrnum);
	}
	else
	{
		if ((i = COM_CheckParm("-width")) && i + 1 < com_argc)
			width = Q_atoi(com_argv[i+1]);

		if ((i = COM_CheckParm("-height")) && i + 1 < com_argc)
			height = Q_atoi(com_argv[i+1]);
	}

	if ((i = COM_CheckParm("-conwidth")) && i + 1 < com_argc)
		vid.conwidth = Q_atoi(com_argv[i+1]);
	else
		vid.conwidth = 640;

	vid.conwidth &= 0xfff8;	// make it a multiple of eight

	if (vid.conwidth < 320)
		vid.conwidth = 320;

	// pick a conheight that matches with correct aspect
	vid.conheight = vid.conwidth * 3 / 4;

	if ((i = COM_CheckParm("-conheight")) && i + 1 < com_argc)
		vid.conheight = Q_atoi(com_argv[i+1]);
	if (vid.conheight < 200)
		vid.conheight = 200;

	// Get video mode list
	MajorVersion = MinorVersion = 0;
	if (!XF86VidModeQueryVersion(dpy, &MajorVersion, &MinorVersion))
	{
		vidmode_ext = false;
	}
	else
	{
		Con_Printf ("Using XFree86-VidModeExtension Version %d.%d\n", MajorVersion, MinorVersion);
		vidmode_ext = true;
	}

	if (vidmode_ext)
	{
		int	best_fit, best_dist, dist, x, y;
		
		XF86VidModeGetAllModeLines (dpy, scrnum, &num_vidmodes, &vidmodes);

		// Are we going fullscreen? If so, let's change video mode
		if (fullscreen)
		{
			best_dist = 9999999;
			best_fit = -1;

			for (i=0 ; i<num_vidmodes ; i++)
			{
				if (width > vidmodes[i]->hdisplay || height > vidmodes[i]->vdisplay)
					continue;

				x = width - vidmodes[i]->hdisplay;
				y = height - vidmodes[i]->vdisplay;
				dist = (x * x) + (y * y);
				if (dist < best_dist)
				{
					best_dist = dist;
					best_fit = i;
				}
			}

			if (best_fit != -1)
			{
				actualWidth = vidmodes[best_fit]->hdisplay;
				actualHeight = vidmodes[best_fit]->vdisplay;

				// change to the mode
				XF86VidModeSwitchToMode (dpy, scrnum, vidmodes[best_fit]);
				vidmode_active = true;

				// Move the viewport to top left
				XF86VidModeSetViewPort (dpy, scrnum, 0, 0);
			}
			else
			{
				fullscreen = false;
			}
		}
	}

	// window attributes
	attr.background_pixel = 0;
	attr.border_pixel = 0;
	attr.colormap = XCreateColormap (dpy, root, visinfo->visual, AllocNone);
	attr.event_mask = X_MASK;
	mask = CWBackPixel | CWBorderPixel | CWColormap | CWEventMask;

	// fullscreen
	if (vidmode_active)
	{
		mask = CWBackPixel | CWColormap | CWEventMask | CWSaveUnder | CWBackingStore | CWOverrideRedirect;
		attr.override_redirect = True;
		attr.backing_store = NotUseful;
		attr.save_under = False;
	}

	win = XCreateWindow (dpy, root, 0, 0, width, height, 0, visinfo->depth, InputOutput, visinfo->visual, mask, &attr);
	XDefineCursor (dpy, win, CreateNullCursor(dpy, win));
	XMapWindow (dpy, win);

	if (vidmode_active)
	{
		XRaiseWindow (dpy, win);
		XWarpPointer (dpy, None, win, 0, 0, 0, 0, 0, 0);
		XFlush (dpy);
		// Move the viewport to top left
		XF86VidModeSetViewPort (dpy, scrnum, 0, 0);
	}

	XFlush (dpy);

	ctx = glXCreateContext (dpy, visinfo, NULL, True);

	glXMakeCurrent (dpy, win, ctx);

	scr_width = width;
	scr_height = height;

	if (vid.conheight > height)
		vid.conheight = height;
	if (vid.conwidth > width)
		vid.conwidth = width;
	vid.width = vid.conwidth;
	vid.height = vid.conheight;

	vid.aspect = ((float)vid.height / (float)vid.width) * (320.0 / 240.0);
	vid.numpages = 2;

	InitSig ();	// trap evil signals

	GL_Init ();

	Check_Gamma (palette);
	VID_SetPalette (palette);

	InitHWGamma ();

	Con_Printf ("Video mode %dx%d initialized.\n", width, height);

	if (fullscreen)
		vid_windowedmouse = false;

	vid.recalc_refdef = 1;			// force a surface cache flush

	if (COM_CheckParm("-fullsbar"))
		fullsbardraw = true;
}

void Sys_SendKeyEvents (void)
{
	if (dpy)
	{
		while (XPending(dpy)) 
			GetEvent ();
	}
}

void Force_CenterView_f (void)
{
	cl.viewangles[PITCH] = 0;
}

void IN_Init (void)
{
	Cmd_AddCommand ("force_centerview", Force_CenterView_f);
}

void IN_Shutdown (void)
{
}

void IN_Commands (void)
{
}

void IN_MouseMove (usercmd_t *cmd)
{
	float	tx, ty;

	tx = mouse_x;
	ty = mouse_y;

	if (m_filter.value)
	{
		mouse_x = (tx + old_mouse_x) * 0.5;
		mouse_y = (ty + old_mouse_y) * 0.5;
	}

	old_mouse_x = tx;
	old_mouse_y = ty;

	mouse_x *= sensitivity.value;
	mouse_y *= sensitivity.value;

	// add mouse X/Y movement to cmd
	if ((in_strafe.state & 1) || (lookstrafe.value && mlook_active))
		cmd->sidemove += m_side.value * mouse_x;
	else
		cl.viewangles[YAW] -= m_yaw.value * mouse_x;

	if (mlook_active)
		V_StopPitchDrift ();

	if (mlook_active && !(in_strafe.state & 1))
	{
		cl.viewangles[PITCH] += m_pitch.value * mouse_y;
		cl.viewangles[PITCH] = bound(-70, cl.viewangles[PITCH], 80);
	}
	else
	{
		if ((in_strafe.state & 1) && noclip_anglehack)
			cmd->upmove -= m_forward.value * mouse_y;
		else
			cmd->forwardmove -= m_forward.value * mouse_y;
	}
	mouse_x = mouse_y = 0.0;
}

void IN_Move (usercmd_t *cmd)
{
	IN_MouseMove (cmd);
}
