/**************************************************************************
 * fg_init.c -- Flight Gear top level initialization routines
 *
 * Written by Curtis Olson, started August 1997.
 *
 * Copyright (C) 1997  Curtis L. Olson  - curt@infoplane.com
 *
 * 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., 675 Mass Ave, Cambridge, MA 02139, USA.
 *
 * $Id$
 * (Log is kept at end of this file)
 **************************************************************************/


#include <stdio.h>
#include <stdlib.h>

#include "fg_init.h"
#include "views.h"

#include "../Include/constants.h"
#include "../Include/general.h"

#include "../Aircraft/aircraft.h"
#include "../Astro/moon.h"
#include "../Astro/sky.h"
#include "../Astro/stars.h"
#include "../Astro/sun.h"
#include "../Cockpit/cockpit.h"
#include "../Joystick/joystick.h"
#include "../Math/fg_random.h"
#include "../Scenery/mesh.h"
#include "../Scenery/scenery.h"
#include "../Scenery/tilemgr.h"
#include "../Time/event.h"
#include "../Time/fg_time.h"
#include "../Time/sunpos.h"
#include "../Weather/weather.h"


extern int show_hud;             /* HUD state */
extern int displayInstruments;


/* General house keeping initializations */

void fgInitGeneral( void ) {
    struct fgGENERAL *g;

    g = &general;

    printf("General Initialization\n");
    printf("======= ==============\n");

    /* seed the random number generater */
    fg_srandom();

    /* determine the fg root path */
    if ( (g->root_dir = getenv("FG_ROOT")) == NULL ) {
	/* environment variable not defined */
	printf("FG_ROOT needs to be defined!  See the documentation.\n");
	exit(0);
    } 
    printf("FG_ROOT = %s\n", g->root_dir);

    printf("\n");
}


/* This is the top level init routine which calls all the other
 * initialization routines.  If you are adding a subsystem to flight
 * gear, its initialization call should located in this routine.*/

void fgInitSubsystems( void ) {
    double cur_elev;

    struct fgFLIGHT *f;
    struct fgLIGHT *l;
    struct fgTIME *t;
    struct fgVIEW *v;

    f = &current_aircraft.flight;
    l = &cur_light_params;
    t = &cur_time_params;
    v = &current_view;

    printf("Initialize Subsystems\n");
    printf("========== ==========\n");

    /****************************************************************
     * The following section sets up the flight model EOM parameters and 
     * should really be read in from one or more files.
     ****************************************************************/

    /* Globe Aiport, AZ */
    FG_Runway_longitude = -398391.28;
    FG_Runway_latitude = 120070.41;
    FG_Runway_altitude = 3234.5;
    FG_Runway_heading = 102.0 * DEG_TO_RAD;

    /* Initial Position at GLOBE airport */
    FG_Longitude = ( -398391.28 / 3600.0 ) * DEG_TO_RAD;
    FG_Latitude  = (  120070.41 / 3600.0 ) * DEG_TO_RAD;
    FG_Altitude = FG_Runway_altitude + 3.758099;
    
    /* Initial Position north of the city of Globe */
    /* FG_Longitude = ( -398673.28 / 3600.0 ) * DEG_TO_RAD; */
    /* FG_Latitude  = (  120625.64 / 3600.0 ) * DEG_TO_RAD; */
    /* FG_Longitude = ( -397867.44 / 3600.0 ) * DEG_TO_RAD; */
    /* FG_Latitude  = (  119548.21 / 3600.0 ) * DEG_TO_RAD; */
    /* FG_Altitude = 0.0 + 3.758099; */

    /* Initial Posisition near where I used to live in Globe, AZ */
    /* FG_Longitude = ( -398757.6 / 3600.0 ) * DEG_TO_RAD; */
    /* FG_Latitude  = (  120160.0 / 3600.0 ) * DEG_TO_RAD; */
    /* FG_Runway_altitude = 5000.0; */
    /* FG_Altitude = FG_Runway_altitude + 3.758099; */

    /* Initial Position: 10125 Jewell St. NE */
    /* FG_Longitude = ( -93.15 ) * DEG_TO_RAD; */
    /* FG_Latitude  = (  45.15 ) * DEG_TO_RAD; */
    /* FG_Altitude = FG_Runway_altitude + 3.758099; */

    /* A random test position */
    /* FG_Longitude = ( 88128.00 / 3600.0 ) * DEG_TO_RAD; */
    /* FG_Latitude  = ( 93312.00 / 3600.0 ) * DEG_TO_RAD; */

    FG_Runway_altitude = 4000.0;
    FG_Altitude = FG_Runway_altitude + 3.758099;

    printf("Initial position is: (%.4f, %.4f, %.2f)\n", 
	   FG_Longitude * RAD_TO_DEG, FG_Latitude * RAD_TO_DEG, 
	   FG_Altitude * FEET_TO_METER);

      /* Initial Velocity */
    FG_V_north = 0.0 /*  7.287719E+00 */;
    FG_V_east  = 0.0 /*  1.521770E+03 */;
    FG_V_down  = 0.0 /* -1.265722E-05 */;

    /* Initial Orientation */
    FG_Phi   = -2.658474E-06;
    FG_Theta =  7.401790E-03;
    FG_Psi   =  270.0 * DEG_TO_RAD;

    /* Initial Angular B rates */
    FG_P_body = 7.206685E-05;
    FG_Q_body = 0.000000E+00;
    FG_R_body = 9.492658E-05;

    FG_Earth_position_angle = 0.000000E+00;

    /* Mass properties and geometry values */
    FG_Mass = 8.547270E+01;
    FG_I_xx = 1.048000E+03;
    FG_I_yy = 3.000000E+03;
    FG_I_zz = 3.530000E+03;
    FG_I_xz = 0.000000E+00;

    /* CG position w.r.t. ref. point */
    FG_Dx_cg = 0.000000E+00;
    FG_Dy_cg = 0.000000E+00;
    FG_Dz_cg = 0.000000E+00;

    /* Set initial position and slew parameters */
    /* fgSlewInit(-398391.3, 120070.41, 244, 3.1415); */ /* GLOBE Airport */
    /* fgSlewInit(-335340,162540, 15, 4.38); */
    /* fgSlewInit(-398673.28,120625.64, 53, 4.38); */

    /* Initialize the event manager */
    fgEventInit();

    /* Dump event stats every 60 seconds */
    fgEventRegister( "fgEventPrintStats()", fgEventPrintStats, 
		     FG_EVENT_READY, 60000 );

    /* Initialize "time" */
    fgTimeInit(t);
    fgTimeUpdate(f, t);

    /* fgViewUpdate() needs the sun in the right place, while
     * fgUpdateSunPos() needs to know the view position.  I'll get
     * around this interdependency for now by calling fgUpdateSunPos()
     * once, then moving on with normal initialization. */
    fgUpdateSunPos();

    /* Initialize view parameters */
    fgViewInit(v);
    fgViewUpdate(f, v, l);

    /* Initialize shared sun position and sun_vec */
    fgEventRegister( "fgUpdateSunPos()", fgUpdateSunPos, FG_EVENT_READY, 1000 );

    /* Initialize the weather modeling subsystem */
    fgWeatherInit();

    /* update the weather for our current position */
    fgEventRegister( "fgWeatherUpdate()", fgWeatherUpdate, 
		     FG_EVENT_READY, 120000 );

    /* Initialize the Cockpit subsystem */
    if( fgCockpitInit( current_aircraft ) == NULL ) {
    	printf( "Error in Cockpit initialization!\n" );
    	exit( 1 );
    }

    /* Initialize the orbital elements of sun, moon and mayor planets */
    fgSolarSystemInit(*t);

    /* Initialize the Stars subsystem */
    fgStarsInit();

    /* Initialize the sun's position */
    fgEventRegister( "fgSunInit()", fgSunInit, FG_EVENT_READY, 600000 );

    /* Intialize the moon's position */
    fgEventRegister( "fgMoonInit()", fgMoonInit, FG_EVENT_READY, 600000 );

    /* Initialize the "sky" */
    fgSkyInit();

    /* Initialize the Scenery Management subsystem */
    fgTileMgrInit();
    /* fgSceneryInit(); */

    /* Tell the Scenery Management system where we are so it can load
     * the correct scenery data */
    fgTileMgrUpdate();
    /* fgSceneryUpdate(FG_Latitude, FG_Longitude, FG_Altitude); */

    /* I'm just sticking this here for now, it should probably move 
     * eventually */
    cur_elev = mesh_altitude(FG_Longitude * RAD_TO_DEG * 3600.0, 
			     FG_Latitude  * RAD_TO_DEG * 3600.0);
    printf("True ground elevation is %.2f meters here.\n", cur_elev);
    if ( cur_elev > -9990.0 ) {
	FG_Runway_altitude = cur_elev * METER_TO_FEET;
    }

    if ( FG_Altitude < FG_Runway_altitude ) {
	FG_Altitude = FG_Runway_altitude + 3.758099;
    }
    printf("Updated position (after elevation adj): (%.4f, %.4f, %.2f)\n", 
	   FG_Latitude * RAD_TO_DEG, FG_Longitude * RAD_TO_DEG, 
	   FG_Altitude * FEET_TO_METER);
    /* end of thing that I just stuck in that I should probably move */

    /* Initialize the flight model subsystem data structures base on
     * above values */
    fgFlightModelInit( FG_LARCSIM, f, 1.0 / DEFAULT_MODEL_HZ );

    /* To HUD or not to HUD */
    show_hud = 0;

    /* Let's show the instrument panel */
    displayInstruments = 0;

    /* Joystick support */
    fgJoystickInit( 0 );

    /* One more try here to get the sky synced up */
    fgSkyColorsInit();

    printf("\n");
}


/* $Log$
/* Revision 1.30  1998/01/13 00:23:09  curt
/* Initial changes to support loading and management of scenery tiles.  Note,
/* there's still a fair amount of work left to be done.
/*
 * Revision 1.29  1998/01/08 02:22:08  curt
 * Beginning to integrate Tile management subsystem.
 *
 * Revision 1.28  1998/01/07 03:18:58  curt
 * Moved astronomical stuff from .../Src/Scenery to .../Src/Astro/
 *
 * Revision 1.27  1998/01/05 18:44:35  curt
 * Add an option to advance/decrease time from keyboard.
 *
 * Revision 1.26  1997/12/30 23:09:04  curt
 * Tweaking initialization sequences.
 *
 * Revision 1.25  1997/12/30 22:22:33  curt
 * Further integration of event manager.
 *
 * Revision 1.24  1997/12/30 20:47:44  curt
 * Integrated new event manager with subsystem initializations.
 *
 * Revision 1.23  1997/12/30 16:36:50  curt
 * Merged in Durk's changes ...
 *
 * Revision 1.22  1997/12/19 23:34:05  curt
 * Lot's of tweaking with sky rendering and lighting.
 *
 * Revision 1.21  1997/12/19 16:45:00  curt
 * Working on scene rendering order and options.
 *
 * Revision 1.20  1997/12/18 23:32:33  curt
 * First stab at sky dome actually starting to look reasonable. :-)
 *
 * Revision 1.19  1997/12/17 23:13:36  curt
 * Began working on rendering a sky.
 *
 * Revision 1.18  1997/12/15 23:54:49  curt
 * Add xgl wrappers for debugging.
 * Generate terrain normals on the fly.
 *
 * Revision 1.17  1997/12/15 20:59:09  curt
 * Misc. tweaks.
 *
 * Revision 1.16  1997/12/12 19:52:48  curt
 * Working on lightling and material properties.
 *
 * Revision 1.15  1997/12/11 04:43:55  curt
 * Fixed sun vector and lighting problems.  I thing the moon is now lit
 * correctly.
 *
 * Revision 1.14  1997/12/10 22:37:47  curt
 * Prepended "fg" on the name of all global structures that didn't have it yet.
 * i.e. "struct WEATHER {}" became "struct fgWEATHER {}"
 *
 * Revision 1.13  1997/11/25 19:25:32  curt
 * Changes to integrate Durk's moon/sun code updates + clean up.
 *
 * Revision 1.12  1997/11/15 18:16:35  curt
 * minor tweaks.
 *
 * Revision 1.11  1997/10/30 12:38:42  curt
 * Working on new scenery subsystem.
 *
 * Revision 1.10  1997/10/25 03:24:23  curt
 * Incorporated sun, moon, and star positioning code contributed by Durk Talsma.
 *
 * Revision 1.9  1997/09/23 00:29:39  curt
 * Tweaks to get things to compile with gcc-win32.
 *
 * Revision 1.8  1997/09/22 14:44:20  curt
 * Continuing to try to align stars correctly.
 *
 * Revision 1.7  1997/09/16 15:50:30  curt
 * Working on star alignment and time issues.
 *
 * Revision 1.6  1997/09/05 14:17:30  curt
 * More tweaking with stars.
 *
 * Revision 1.5  1997/09/04 02:17:36  curt
 * Shufflin' stuff.
 *
 * Revision 1.4  1997/08/27 21:32:26  curt
 * Restructured view calculation code.  Added stars.
 *
 * Revision 1.3  1997/08/27 03:30:19  curt
 * Changed naming scheme of basic shared structures.
 *
 * Revision 1.2  1997/08/25 20:27:23  curt
 * Merged in initial HUD and Joystick code.
 *
 * Revision 1.1  1997/08/23 01:46:20  curt
 * Initial revision.
 *
 */