/*
	screen.c

	master for refresh, status bar, console, chat, notify, etc

	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:

		Free Software Foundation, Inc.
		59 Temple Place - Suite 330
		Boston, MA  02111-1307, USA

*/
#ifdef HAVE_CONFIG_H
# include "config.h"
#endif

#ifdef HAVE_STRING_H
# include <string.h>
#endif
#ifdef HAVE_STRINGS_H
# include <strings.h>
#endif

#include "QF/cmd.h"
#include "QF/cvar.h"
#include "QF/draw.h"
#include "QF/image.h"
#include "QF/pcx.h"
#include "QF/render.h"
#include "QF/screen.h"
#include "QF/sys.h"
#include "QF/view.h"

#include "compat.h"
#include "r_internal.h"
#include "sbar.h"

/*
	background clear
	rendering
	turtle/net/ram icons
	sbar
	centerprint / slow centerprint
	notify lines
	intermission / finale overlay
	loading plaque
	console
	menu

	required background clears
	required update regions

	syncronous draw mode or async
	One off screen buffer, with updates either copied or xblited
	Need to double buffer?

	async draw will require the refresh area to be cleared, because it will be
	xblited, but sync draw can just ignore it.

	sync
	draw

	CenterPrint ()
	SlowPrint ()
	Screen_Update ();
	Sys_Printf ();

	net
	turn off messages option

	the refresh is always rendered, unless the console is full screen

	console is:
		notify lines
		half
		full
*/

// only the refresh window will be updated unless these variables are flagged
int         scr_copytop;
byte       *draw_chars;					// 8*8 graphic characters FIXME location

int         oldsbar;

qboolean    r_cache_thrash;		// set if surface cache is thrashing

qboolean    scr_initialized;			// ready to draw

qpic_t     *scr_ram;
qpic_t     *scr_turtle;

int         clearconsole;

vrect_t    *pconupdate;
vrect_t     scr_vrect;

qboolean    scr_skipupdate;

void
R_SetVrect (const vrect_t *vrectin, vrect_t *vrect, int lineadj)
{
	float       size;
	int         h;

	// intermission is always full screen
	size = min (r_viewsize, 100);
	if (r_data->force_fullscreen) {
		size = 100.0;
		lineadj = 0;
	}
	size /= 100.0;

	h = vrectin->height - lineadj;

	vrect->width = vrectin->width * size + 0.5;
	if (vrect->width < 96) {
		size = 96.0 / vrectin->width;
		vrect->width = 96;				// min for icons
	}
	vrect->width &= ~7;

	vrect->height = vrectin->height * size + 0.5;
	if (vrect->height > h)
		vrect->height = h;
	vrect->height &= ~1;

	vrect->x = (vrectin->width - vrect->width) / 2;
	vrect->y = (h - vrect->height) / 2;
}

static float __attribute__((pure))
CalcFov (float fov_x, float width, float height)
{
	float       a, x;

	if (fov_x < 1 || fov_x > 179)
		Sys_Error ("Bad fov: %f", fov_x);

	x = width / tan (fov_x * (M_PI / 360));

	a = (x == 0) ? 90 : atan (height / x);	// 0 shouldn't happen

	a = a * (360 / M_PI);

	return a;
}

void
SCR_CalcRefdef (void)
{
	vrect_t     vrect;
	refdef_t   *refdef = r_data->refdef;

	refdef->fov_y = CalcFov (refdef->fov_x, refdef->vrect.width,
							 refdef->vrect.height);

	// force a background redraw
	r_data->scr_fullupdate = 0;
	r_data->vid->recalc_refdef = 0;

	// bound field of view
	Cvar_SetValue (scr_fov, bound (1, scr_fov->value, 170));

	vrect.x = 0;
	vrect.y = 0;
	vrect.width = r_data->vid->width;
	vrect.height = r_data->vid->height;

	R_SetVrect (&vrect, &scr_vrect, r_data->lineadj);

	refdef->vrect = scr_vrect;

	// notify the refresh of the change
	r_funcs->R_ViewChanged ();
}

/*
	SCR_UpdateScreen

	This is called every frame, and can also be called explicitly to flush
	text to the screen.

	WARNING: be very careful calling this from elsewhere, because the refresh
	needs almost the entire 256k of stack space!
*/
void
SCR_UpdateScreen (double realtime, SCR_Func scr_3dfunc, SCR_Func *scr_funcs)
{
	if (scr_skipupdate || !scr_initialized) {
		return;
	}

	r_data->realtime = realtime;
	scr_copytop = r_data->scr_copyeverything = 0;

	if (r_data->vid->recalc_refdef) {
		SCR_CalcRefdef ();
	}

	r_funcs->R_RenderFrame (scr_3dfunc, scr_funcs);
}

void
SCR_SetFOV (float fov)
{
	refdef_t   *refdef = r_data->refdef;
	refdef->fov_x = fov;
	r_data->vid->recalc_refdef = 1;
}

static void
ScreenShot_f (void)
{
	r_funcs->SCR_ScreenShot_f ();
}

/*
	SCR_SizeUp_f

	Keybinding command
*/
static void
SCR_SizeUp_f (void)
{
	if (scr_viewsize->int_val < 120) {
		Cvar_SetValue (scr_viewsize, scr_viewsize->int_val + 10);
		r_data->vid->recalc_refdef = 1;
	}
}

/*
	SCR_SizeDown_f

	Keybinding command
*/
static void
SCR_SizeDown_f (void)
{
	Cvar_SetValue (scr_viewsize, scr_viewsize->int_val - 10);
	r_data->vid->recalc_refdef = 1;
}

void
SCR_DrawRam (void)
{
	if (!scr_showram->int_val)
		return;

	if (!r_cache_thrash)
		return;

	r_funcs->Draw_Pic (scr_vrect.x + 32, scr_vrect.y, scr_ram);
}

void
SCR_DrawTurtle (void)
{
	static int  count;

	if (!scr_showturtle->int_val)
		return;

	if (r_data->frametime < 0.1) {
		count = 0;
		return;
	}

	count++;
	if (count < 3)
		return;

	r_funcs->Draw_Pic (scr_vrect.x, scr_vrect.y, scr_turtle);
}

void
SCR_DrawPause (void)
{
	qpic_t     *pic;

	if (!scr_showpause->int_val)		// turn off for screenshots
		return;

	if (!r_data->paused)
		return;

	pic = r_funcs->Draw_CachePic ("gfx/pause.lmp", true);
	r_funcs->Draw_Pic ((r_data->vid->conwidth - pic->width) / 2,
					   (r_data->vid->conheight - 48 - pic->height) / 2, pic);
}

void
SCR_SetUpToDrawConsole (void)
{
}

/*
	Find closest color in the palette for named color
*/
int
MipColor (int r, int g, int b)
{
	float       bestdist, dist;
	int         r1, g1, b1, i;
	int         best = 0;
	static int  lastbest;
	static int  lr = -1, lg = -1, lb = -1;

	if (r == lr && g == lg && b == lb)
		return lastbest;

	bestdist = 256 * 256 * 3;

	for (i = 0; i < 256; i++) {
		int         j;
		j = i * 3;
		r1 = r_data->vid->palette[j] - r;
		g1 = r_data->vid->palette[j + 1] - g;
		b1 = r_data->vid->palette[j + 2] - b;
		dist = r1 * r1 + g1 * g1 + b1 * b1;
		if (dist < bestdist) {
			bestdist = dist;
			best = i;
		}
	}
	lr = r;
	lg = g;
	lb = b;
	lastbest = best;
	return best;
}

// in draw.c

static void
SCR_DrawCharToSnap (int num, byte *dest, int width)
{
	byte       *source;
	int         col, row, drawline, x;

	row = num >> 4;
	col = num & 15;
	source = draw_chars + (row << 10) + (col << 3);

	drawline = 8;

	while (drawline--) {
		for (x = 0; x < 8; x++)
			if (source[x])
				dest[x] = source[x];
			else
				dest[x] = 98;
		source += 128;
		dest -= width;
	}

}

void
SCR_DrawStringToSnap (const char *s, tex_t *tex, int x, int y)
{
	byte       *dest;
	byte       *buf = tex->data;
	const unsigned char *p;
	int         width = tex->width;

	dest = buf + ((y * width) + x);

	p = (const unsigned char *) s;
	while (*p) {
		SCR_DrawCharToSnap (*p++, dest, width);
		dest += 8;
	}
}

void
SCR_Init (void)
{
	// register our commands
	Cmd_AddCommand ("screenshot", ScreenShot_f, "Take a screenshot, "
					"saves as qfxxx.pcx in the current directory");
	Cmd_AddCommand ("sizeup", SCR_SizeUp_f, "Increases the screen size");
	Cmd_AddCommand ("sizedown", SCR_SizeDown_f, "Decreases the screen size");

	scr_ram = r_funcs->Draw_PicFromWad ("ram");
	scr_turtle = r_funcs->Draw_PicFromWad ("turtle");

	scr_initialized = true;
}