/* Do not remove the headers from this file! see /USAGE for more info. */

/*
** sw_user.c -- switch the actual user
**
** 14-Jun-95.  Deathblade.  Created.
*/
#include <security.h>
#include <commands.h>

string query_userid();
object query_body();
void initialize_user();
string query_userid();
void restore_me(string some_name, int preserve_vars);

varargs void switch_body(string new_body_fname, int permanent);

void register_failure(string addr);

void modal_simple(function input_func, mixed prompt, int secure);

void set_privilege(mixed priv);		// from M_ACCESS
varargs mixed unguarded(mixed priv, function code);

void clear_input_stack();


private nomask int do_su(string old_userid, string new_userid, string new_body)
{
    object body;
    string old_name;
    string new_name;

    write("\n");

    if (query_body())
	old_name = query_body()->query_name();

    /*
    ** The input stack needs to be cleared before we switch bodies so that
    ** the shell the body creates becomes the bottom object on the input 
    ** stack.  -- Rust
    */
    clear_input_stack();

    /*
    ** switch user, then switch body.  Note on switching user:  pass
    ** flag == 1 so that we do not blow away nosave variables (the
    ** old body).
    */
    restore_me(new_userid, 1);

    /* If there is a new_body, that probably means we are changing races.  
     * If that is the case the change needs to be permanent. --Tigran */
    if((!new_body||new_body==""))
      switch_body(new_body,0);
    else
      switch_body(new_body,1);

    /* alter privileges */
    if ( adminp(query_userid()) )
	set_privilege(1);
    else
	set_privilege(query_userid());
    
    body = query_body();
    new_name = body->query_name();
    if ( old_userid != new_userid )
    {
	if (old_name)
	    tell_environment(body,
			     sprintf("%s has polymorphed into %s.\n",
				     old_name, new_name), 0,
			     ({ body }) );
    }
    receive(sprintf("Done. You are now %s.\n", new_name));

    /* 
     * Run through the rest of the initialization routine for users
     */
    initialize_user();
}

private nomask void confirm_valid_su(string old_userid,
				     string new_userid,
				     string new_body,
				     string arg)
{
    string pwd;

    /* new_userid should exist and therefore the return value should be ok */
    pwd = unguarded(1, (: call_other, USER_D, "query_variable",
			new_userid, ({ "password" }) :))[0];

    if ( crypt(arg, pwd) != pwd )
    {
	write("\nWrong password.\n");
	register_failure(sprintf("(su to %s)", new_userid));
	return;
    }

    do_su(old_userid, new_userid, new_body);
}

nomask void switch_user(string str, string new_body)
{
    string old_userid = query_userid();
    string new_userid = lower_case(str);
    int is_admin = adminp(old_userid);

    if ( previous_object() != find_object(CMD_OB_SU) )
	return;

    new_userid = lower_case(str);
    if ( !SECURE_D->valid_name(new_userid) )
    {
	printf("'%s' is an invalid name.\n", str);
	return;
    }

    if ( new_userid != old_userid )
    {
	string linkpath = LINK_PATH(new_userid) + __SAVE_EXTENSION__;

	if( unguarded(1, (: file_size($(linkpath)) :)) <= 0 )
	{
	    write("No such user.\n");
	    return;
	}
    }

    if ( is_admin || new_userid == old_userid )
    {
	do_su(old_userid, new_userid, new_body);
	return;
    }

    printf("switching to: '%s'\n", new_userid);

    modal_simple((: confirm_valid_su, old_userid, new_userid, new_body :),
		 "Password: ",
		 1);
}