/* File: main.c */

/* Purpose: initialization, main() function and main loop */

/*
 * Copyright (c) 1989 James E. Wilson, Robert A. Koeneke
 *
 * This software may be copied and distributed for educational, research, and
 * not for profit purposes provided that this copyright and statement are
 * included in all such copies.
 */

#include "angband.h"


/*
 * Some machines have a "main()" function in their "main-xxx.c" file,
 * all the others use this file for their "main()" function.
 */


#if !defined(MACINTOSH) && !defined(WINDOWS) && !defined(ACORN)


#ifdef SET_UID

/*
 * Check "wizard permissions"
 */
static bool is_wizard(int uid)
{
    FILE        *fp;

    bool        allow = FALSE;

    char        buf[1024];


    /* Access the "wizards.txt" file */
    strcpy(buf, ANGBAND_DIR_FILE);
    strcat(buf, "wizards.txt");

    /* Open the wizard file */
    fp = my_fopen(buf, "r");

    /* No file, allow everyone */
    if (!fp) return (TRUE);

    /* Scan the wizard file */
    while (0 == my_fgets(fp, buf, 1024))
    {
	int test;

	/* Skip comments and blank lines */
	if (!buf[0] || (buf[0] == '#')) continue;

	/* Look for valid entries */
	if (sscanf(buf, "%d", &test) != 1) continue;

	/* Look for matching entries */
	if (test == uid) allow = TRUE;

	/* Done */
	if (allow) break;
    }

    /* Close the file */
    my_fclose(fp);

    /* Result */
    return (allow);
}

#endif


/*
 * A hook for "quit()".
 *
 * Close down, then fall back into "quit()".
 */
static void quit_hook(cptr s)
{
    /* Shut down the term windows */
    if (term_choice) term_nuke(term_choice);
    if (term_recall) term_nuke(term_recall);
    if (term_mirror) term_nuke(term_mirror);
    if (term_screen) term_nuke(term_screen);
}



/*
 * Set the stack size (for the Amiga)
 */
#ifdef AMIGA
# include <dos.h>
__near long __stack = 32768L;
#endif


/*
 * Set the stack size and overlay buffer (see main-286.c")
 *
 * XXX XXX XXX Note that "<dos.h>" defines the "delay()" function.
 */
#ifdef USE_286
# include <dos.h>
extern unsigned _stklen = 32768U;
extern unsigned _ovrbuffer = 0x1500;
#endif

/*
 * Initialize and verify the file paths, and the score file.
 *
 * Use the ANGBAND_PATH environment var if possible, else use
 * DEFAULT_PATH, and in either case, branch off appropriately.
 *
 * First, we'll look for the ANGBAND_PATH environment variable,
 * and then look for the files in there.  If that doesn't work,
 * we'll try the DEFAULT_PATH constant.  So be sure that one of
 * these two things works...
 *
 * We must ensure that the path ends with "PATH_SEP" if needed.
 *
 * Note that the "path" must be "Angband:" for the Amiga, and it
 * is ignored for "VM/ESA", so I just combined the two.
 */
static void init_stuff(void)
{
    char path[1024];


#if defined(AMIGA) || defined(VM)

    /* Hack -- prepare "path" */
    strcpy(path, "Angband:");

#else /* AMIGA / VM */

    cptr tail;

    /* Get the environment variable */
    tail = getenv("ANGBAND_PATH");

    /* Use the angband_path, or a default */
    strcpy(path, tail ? tail : DEFAULT_PATH);

    /* Hack -- Add a path separator (only if needed) */
    if (!suffix(path, PATH_SEP)) strcat(path, PATH_SEP);

#endif /* AMIGA / VM */

    /* Initialize */
    init_file_paths(path);
}



/*
 * Studly machines can actually parse command line args
 *
 * XXX XXX XXX The "-c", "-d", and "-i" options should probably require
 * that their "arguments" end in the appropriate path separator.  But it
 * is possible to use them without a path separator, which provides a
 * special "prefix" for all of the file names.  Those options should
 * probably be simplified into some form of "-dWHAT=PATH" syntax.
 */
int main(int argc, char *argv[])
{
    bool done = FALSE;

    bool new_game = FALSE;

    int show_score = 0;


    /* Save the "program name" */
    argv0 = argv[0];


#ifdef USE_286
    /* Attempt to use XMS (or EMS) memory for swap space */
    if (_OvrInitExt(0L, 0L))
    {
       _OvrInitEms(0,0,64);
    }
#endif


#ifdef SET_UID

    /* Default permissions on files */
    (void)umask(022);

# ifdef SECURE
    /* Authenticate */
    Authenticate();
# endif

#endif


    /* Get the file paths */
    init_stuff();


#ifdef SET_UID

    /* Get the user id (?) */
    player_uid = getuid();

#ifdef VMS
    /* Mega-Hack -- Factor group id */
    player_uid += (getgid() * 1000);
#endif

# ifdef SAFE_SETUID

#  ifdef _POSIX_SAVED_IDS

    /* Save some info for later */
    player_euid = geteuid();
    player_egid = getegid();

#  endif

#  if 0 /* XXX XXX XXX */

    /* Redundant setting necessary in case root is running the game */
    /* If not root or game not setuid the following two calls do nothing */

    if (setgid(getegid()) != 0)
    {
      quit("setgid(): cannot set permissions correctly!");
    }

    if (setuid(geteuid()) != 0)
    {
      quit("setuid(): cannot set permissions correctly!");
    }

#  endif

# endif

#endif


    /* Assume "Wizard" permission */
    can_be_wizard = TRUE;

#ifdef SET_UID

    /* Check for "Wizard" permission */
    can_be_wizard = is_wizard(player_uid);

    /* Initialize the "time" checker */
    if (check_time_init() || check_time())
    {
	quit("The gates to Angband are closed (bad time).");
    }

    /* Initialize the "load" checker */
    if (check_load_init() || check_load())
    {
	quit("The gates to Angband are closed (bad load).");
    }

    /* Acquire the "user name" as a default player name */
    user_name(player_name, player_uid);

#endif


    /* Process the command line arguments */
    for (--argc, ++argv; argc > 0; --argc, ++argv)
    {
	/* Require proper options */
	if (argv[0][0] != '-') goto usage;

	/* Analyze option */
	switch (argv[0][1])
	{
	    case 'c':
	    case 'C':
		ANGBAND_DIR_USER = &argv[0][2];
		break;

#ifndef VERIFY_SAVEFILE
	    case 'd':
	    case 'D':
		ANGBAND_DIR_SAVE = &argv[0][2];
		break;
#endif

	    case 'i':
	    case 'I':
		ANGBAND_DIR_INFO = &argv[0][2];
		break;

	    case 'N':
	    case 'n':
		new_game = TRUE;
		break;

	    case 'V':
	    case 'v':
		use_sound = TRUE;
		break;

	    case 'G':
	    case 'g':
		use_graphics = TRUE;
		break;

	    case 'S':
	    case 's':
		show_score = atoi(&argv[0][2]);
		if (show_score <= 0) show_score = 10;
		break;

	    case 'F':
	    case 'f':
		arg_fiddle = TRUE;
		break;

#ifdef SET_UID
	    case 'P':
	    case 'p':
		if (can_be_wizard)
		{
		    player_uid = atoi(&argv[0][2]);
		    user_name(player_name, player_uid);
		}
		break;
#endif

	    case 'W':
	    case 'w':
		if (can_be_wizard) arg_wizard = TRUE;
		break;

	    case 'u':
	    case 'U':
		if (!argv[0][2]) goto usage;
		strcpy(player_name, &argv[0][2]);
		break;

	    default:
	    usage:

		/* Note -- the Term is NOT initialized */
		puts("Usage: angband [options]");
		puts("  -n       Start a new character");
		puts("  -v       Activate the use_sound flag");
		puts("  -g       Activate the use_graphics flag");
		puts("  -f       Activate 'fiddle' mode");
		puts("  -w       Activate 'wizard' mode");
		puts("  -p<uid>  Play with the <uid> userid");
		puts("  -u<name> Play with your <name> savefile");
		puts("  -s<num>  Show <num> high scores (or top 10).");
		puts("  -c<path> Look for pref files in the directory <path>");
		puts("  -d<path> Look for save files in the directory <path>");
		puts("  -i<path> Look for info files in the directory <path>");

		/* Actually abort the process */
		quit(NULL);
	}
    }


    /* Process the player name */
    process_player_name(TRUE);



    /* Drop privs (so X11 will work correctly) */
    safe_setuid_drop();


#ifdef USE_XAW
    /* Attempt to use the "main-xaw.c" support */
    if (!done)
    {
	extern errr init_xaw(void);
	if (0 == init_xaw()) done = TRUE;
	if (done) ANGBAND_SYS = "xaw";
    }
#endif

#ifdef USE_X11
    /* Attempt to use the "main-x11.c" support */
    if (!done)
    {
	extern errr init_x11(void);
	if (0 == init_x11()) done = TRUE;
	if (done) ANGBAND_SYS = "x11";
    }
#endif


#ifdef USE_GCU
    /* Attempt to use the "main-gcu.c" support */
    if (!done)
    {
	extern errr init_gcu(void);
	if (0 == init_gcu()) done = TRUE;
	if (done) ANGBAND_SYS = "gcu";
    }
#endif

#ifdef USE_CAP
    /* Attempt to use the "main-cap.c" support */
    if (!done)
    {
	extern errr init_cap(void);
	if (0 == init_cap()) done = TRUE;
	if (done) ANGBAND_SYS = "cap";
    }
#endif


#ifdef USE_IBM
    /* Attempt to use the "main-ibm.c" support */
    if (!done)
    {
	extern errr init_ibm(void);
	if (0 == init_ibm()) done = TRUE;
	if (done) ANGBAND_SYS = "ibm";
    }
#endif

#ifdef __EMX__
    /* Attempt to use the "main-emx.c" support */
    if (!done)
    {
	extern errr init_emx(void);
	if (0 == init_emx()) done = TRUE;
	if (done) ANGBAND_SYS = "emx";
    }
#endif


#ifdef USE_SLA
    /* Attempt to use the "main-sla.c" support */
    if (!done)
    {
	extern errr init_sla(void);
	if (0 == init_sla()) done = TRUE;
	if (done) ANGBAND_SYS = "sla";
    }
#endif


#ifdef USE_LSL
    /* Attempt to use the "main-lsl.c" support */
    if (!done)
    {
	extern errr init_lsl(void);
	if (0 == init_lsl()) done = TRUE;
	if (done) ANGBAND_SYS = "lsl";
    }
#endif


#ifdef USE_AMI
    /* Attempt to use the "main-ami.c" support */
    if (!done)
    {
	extern errr init_ami(void);
	if (0 == init_ami()) done = TRUE;
	if (done) ANGBAND_SYS = "ami";
    }
#endif


#ifdef USE_VME
    /* Attempt to use the "main-vme.c" support */
    if (!done)
    {
	extern errr init_vme(void);
	if (0 == init_vme()) done = TRUE;
	if (done) ANGBAND_SYS = "vme";
    }
#endif


    /* Grab privs (dropped above for X11) */
    safe_setuid_grab();


    /* Make sure we have a display! */
    if (!done) quit("Unable to prepare any 'display module'!");


    /* Tell "quit()" to call "Term_nuke()" */
    quit_aux = quit_hook;


    /* If requested, display scores and quit */
    if (show_score > 0) display_scores(0, show_score);


    /* Catch nasty signals */
    signals_init();

    /* Display the 'news' file */
    show_news();

    /* Initialize the arrays */
    init_some_arrays();

    /* Wait for response */
    pause_line(23);

    /* Play the game */
    play_game(new_game);

    /* Quit */
    quit(NULL);

    /* Exit */
    return (0);
}

#endif