/*
// ColdMUD was created and is copyright 1993, 1994 by Greg Hudson
//
// ColdX is a derivitive work, and is copyright 1995 by the ColdX Project.
// Full copyright information can be found in the file doc/CREDITS
//
// File:        main.c
// Version:     0.1-5
// Last Edited: 4 Aug 1995
//
// ---
//
//
*/

/* #define _POSIX_SOURCE */

#define _main_

#include "config.h"

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <time.h>
#include "defs.h"
#include "x.tab.h"
#include "codegen.h"
#include "opcodes.h"
#include "object.h"
#include "match.h"
#include "cache.h"
#include "sig.h"
#include "db.h"
#include "util.h"
#include "io.h"
#include "data.h"
#include "log.h"
#include "dump.h"
#include "execute.h"
#include "ident.h"
#include "cmstring.h"
#include "token.h"

#include "main.h"

/* -------------------------------------------------------------------- */
int main(int argc, char **argv) {
    initialize(argc, argv);
    main_loop();

    /* Sync the cache, flush output buffers, and exit normally. */
    cache_sync();
    db_close();
    flush_output();

    return 0;
}

/* -------------------------------------------------------------------- */
static void initialize(int argc, char **argv) {
    FILE    * fp;
    Object  * obj;
    List    * parents,
            * args;
    int       i,
              use_text_dump;
    String  * str;
    Data      arg,
            * d;

    /* Ditch stdin, so we can reuse the file descriptor */
    fclose(stdin);

    /* Initialize internal tables and variables. */
    init_codegen();
    init_ident();
    init_op_table();
    init_match();
    init_util();
    init_sig();
    init_execute();
    init_scratch_file();
    init_token();

    if (argc < 2) {
	fprintf(stderr, "Usage: %s <database> <db args>\n",  argv[0]);
        /*
            -d basedir
            -f filedir
            -c compile <stdin>
        */
	exit(1);
    }

    /* Switch into database directory. */
    if (chdir(argv[1]) == -1) {
	fprintf(stderr, "Couldn't change to directory %s.\n", argv[1]);
	exit(1);
    }

    /* Build argument list from arguments. */
    args = list_new(argc);
    d = list_empty_spaces(args, argc);
    for (i = 0; i < argc; i++) {
	str = string_from_chars(argv[i], strlen(argv[i]));
	d->type = STRING;
	d->u.str = str;
	d++;
    }

    /* people like to know what is up */
    write_err("Initializing database...");

    /* Initialize database and network modules. */
    init_cache();
    use_text_dump = init_db();

    /* Order of operations note: it might seem like we'd want to read the text
     * dump (if we're going to) before making sure there's a root and system
     * object.  However, this way is correct, since the textdump reader can
     * evaluate arbitrary C-- code and thus should start with a consistent
     * database. */

    /* Make sure there is a root object. */
    obj = cache_retrieve(ROOT_DBREF);
    if (!obj) {
	parents = list_new(0);
	obj = object_new(ROOT_DBREF, parents);
	list_discard(parents);
    }
    cache_discard(obj);

    /* Make sure there is a system object. */
    obj = cache_retrieve(SYSTEM_DBREF);
    if (!obj) {
	parents = list_new(1);
	d = list_empty_spaces(parents, 1);
	d->type = DBREF;
	d->u.dbref = ROOT_DBREF;
	obj = object_new(SYSTEM_DBREF, parents);
	list_discard(parents);
    }
    cache_discard(obj);

    /* Read a text dump if there was no existing binary database. */
    if (use_text_dump) {
        write_err("Reading from textdump...");
	fp = fopen("textdump", "r");
	if (!fp) {
	    fail_to_start("Couldn't open text dump file.");
	} else {
	    text_dump_read(fp);
	    fclose(fp);
	}
    }

    /* Send a startup message to the system object. */
    arg.type = LIST;
    arg.u.list = args;
    task(NULL, SYSTEM_DBREF, startup_id, 1, &arg);
    list_discard(args);
}

/* -------------------------------------------------------------------- */
static void main_loop(void) {
    int             seconds = 0;
    time_t          next_heartbeat = 0, t;

    while (running) {
	/* delete any defunct connection or server records */
	flush_defunct();

	/* Sanity check: make sure there are no objects in active chains. */
	/*	cache_sanity_check(); */

	/* Find number of seconds before next heartbeat. */
	if (heartbeat_freq != -1) {
	    next_heartbeat = (last_heartbeat -
			      (last_heartbeat % heartbeat_freq)
			      ) + heartbeat_freq;
	    time(&t);
	    seconds = (t >= next_heartbeat) ? 0 : next_heartbeat - t;
	    seconds = (paused ? 0 : seconds);
            /* fprintf(stderr, "seconds: %d\n", seconds); */
	}

        /* wait seconds for something to happen */
        handle_io_event_wait(seconds);

        /* input */
        handle_connection_input();

        /* handle new or pending connections */
	handle_new_and_pending_connections();

        /* send a heartbeat if necessary */
	if (heartbeat_freq != -1) {
	    time(&t);
	    if (t >= next_heartbeat) {
		last_heartbeat = t;
		task(NULL, SYSTEM_DBREF, heartbeat_id, 0);
	    }
	}

        /* output */
        handle_connection_output();

        /* complete paused tasks */
	if (paused)
            run_paused_tasks();
    }
}

#undef _main_