! LockTest An inform library to choose default keys

! LockTest An inform library to choose default keys
! By L. Ross Raszewski
!
! By giving any key the "is_key" attribute, the commands "Lock" and "Unlock"
! will choose a default key if only one is held. If more than one key is held,
! it checks the property "key_to". If only one object has an entry in its
! key_to array matching the object to be unlocked, it will be chosen as the
! default key. This way, the game can recognise obvious keys, such as a
! "gold key" to a "gold door". If you think that this will give away a puzzle,
! just don't give that object a key_to value.
!
! This library IS compatible with the improved multi-key locking function by
! the author
!

#IFNDEF key_to;
property key_to $ffff;
#ENDIF;
global assumed_key;
attribute is_key;
[ DefaultUnlockSub;
print "(with ", (the) assumed_key, ".)^";
<<Unlock noun assumed_key>>;
];
[ DefaultLockSub;
print "(with ", (the) assumed_key, ".)^";
<<Lock noun assumed_key>>;
];
[ DefaultKeyTest i j count;
if (noun hasnt lockable) rfalse;
objectloop (i in player)
if (i has is_key) { count++; assumed_key=i;};
if (count==1) rtrue;
if (count>1) {
count=0;
objectloop (i in player)
{ if (i has is_key)
{ for (j=0:j<=(i.#key_to):j++)
if ((i.&key_to)-->j==noun)
{count++; assumed_key=i;};};};};
if (count==1) rtrue;
rfalse;
];
Extend "lock" first * noun=DefaultKeyTest ->DefaultLock;
Extend "unlock" first * noun=DefaultKeyTest ->DefaultUnlock;